~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP
M68000 Hi-Performance Microprocessor Division
M68060 Software Package
Production Release P1.00 -- October 10, 1994

M68060 Software Package Copyright © 1993, 1994 Motorola Inc.  All rights reserved.
 
THE SOFTWARE is provided on an "AS IS" basis and without warranty.
To the maximum extent permitted by applicable law,
MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED, 
INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
and any warranty against infringement with regard to the SOFTWARE
(INCLUDING ANY MODIFIED VERSIONS THEREOF) and any accompanying written materials.

To the maximum extent permitted by applicable law,
IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER
(INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS,
BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR OTHER PECUNIARY LOSS)
ARISING OF THE USE OR INABILITY TO USE THE SOFTWARE.
Motorola assumes no responsibility for the maintenance and support of the SOFTWARE.

You are hereby granted a copyright license to use, modify, and distribute the SOFTWARE
so long as this entire notice is retained without alteration in any modified and/or
redistributed versions, and that such modified versions are clearly identified as such.
No licenses are granted by implication, estoppel or otherwise under any patents
or trademarks of Motorola, Inc.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#
# freal.s:
#	This file is appended to the top of the 060FPSP package
# and contains the entry points into the package. The user, in
# effect, branches to one of the branch table entries located
# after _060FPSP_TABLE.
#	Also, subroutine stubs exist in this file (_fpsp_done for
# example) that are referenced by the FPSP package itself in order
# to call a given routine. The stub routine actually performs the
# callout. The FPSP code does a "bsr" to the stub routine. This
# extra layer of hierarchy adds a slight performance penalty but
# it makes the FPSP code easier to read and more mainatinable.
#

set	_off_bsun,	0x00
set	_off_snan,	0x04
set	_off_operr,	0x08
set	_off_ovfl,	0x0c
set	_off_unfl,	0x10
set	_off_dz,	0x14
set	_off_inex,	0x18
set	_off_fline,	0x1c
set	_off_fpu_dis,	0x20
set	_off_trap,	0x24
set	_off_trace,	0x28
set	_off_access,	0x2c
set	_off_done,	0x30

set	_off_imr,	0x40
set	_off_dmr,	0x44
set	_off_dmw,	0x48
set	_off_irw,	0x4c
set	_off_irl,	0x50
set	_off_drb,	0x54
set	_off_drw,	0x58
set	_off_drl,	0x5c
set	_off_dwb,	0x60
set	_off_dww,	0x64
set	_off_dwl,	0x68

_060FPSP_TABLE:

###############################################################

# Here's the table of ENTRY POINTS for those linking the package.
	bra.l		_fpsp_snan
	short		0x0000
	bra.l		_fpsp_operr
	short		0x0000
	bra.l		_fpsp_ovfl
	short		0x0000
	bra.l		_fpsp_unfl
	short		0x0000
	bra.l		_fpsp_dz
	short		0x0000
	bra.l		_fpsp_inex
	short		0x0000
	bra.l		_fpsp_fline
	short		0x0000
	bra.l		_fpsp_unsupp
	short		0x0000
	bra.l		_fpsp_effadd
	short		0x0000

	space 		56

###############################################################
	global		_fpsp_done
_fpsp_done:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_done,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_ovfl
_real_ovfl:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_ovfl,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_unfl
_real_unfl:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_unfl,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_inex
_real_inex:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_inex,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_bsun
_real_bsun:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_bsun,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_operr
_real_operr:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_operr,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_snan
_real_snan:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_snan,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_dz
_real_dz:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_dz,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_fline
_real_fline:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_fline,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_fpu_disabled
_real_fpu_disabled:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_fpu_dis,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_trap
_real_trap:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_trap,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_trace
_real_trace:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_trace,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_real_access
_real_access:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_access,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

#######################################

	global		_imem_read
_imem_read:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_imr,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_read
_dmem_read:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_dmr,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_write
_dmem_write:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_dmw,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_imem_read_word
_imem_read_word:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_irw,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_imem_read_long
_imem_read_long:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_irl,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_read_byte
_dmem_read_byte:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_drb,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_read_word
_dmem_read_word:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_drw,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_read_long
_dmem_read_long:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_drl,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_write_byte
_dmem_write_byte:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_dwb,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_write_word
_dmem_write_word:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_dww,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

	global		_dmem_write_long
_dmem_write_long:
	mov.l		%d0,-(%sp)
	mov.l		(_060FPSP_TABLE-0x80+_off_dwl,%pc),%d0
	pea.l		(_060FPSP_TABLE-0x80,%pc,%d0)
	mov.l		0x4(%sp),%d0
	rtd		&0x4

#
# This file contains a set of define statements for constants
# in order to promote readability within the corecode itself.
#

set LOCAL_SIZE,		192			# stack frame size(bytes)
set LV,			-LOCAL_SIZE		# stack offset

set EXC_SR,		0x4			# stack status register
set EXC_PC,		0x6			# stack pc
set EXC_VOFF,		0xa			# stacked vector offset
set EXC_EA,		0xc			# stacked <ea>

set EXC_FP,		0x0			# frame pointer

set EXC_AREGS,		-68			# offset of all address regs
set EXC_DREGS,		-100			# offset of all data regs
set EXC_FPREGS,		-36			# offset of all fp regs

set EXC_A7,		EXC_AREGS+(7*4)		# offset of saved a7
set OLD_A7,		EXC_AREGS+(6*4)		# extra copy of saved a7
set EXC_A6,		EXC_AREGS+(6*4)		# offset of saved a6
set EXC_A5,		EXC_AREGS+(5*4)
set EXC_A4,		EXC_AREGS+(4*4)
set EXC_A3,		EXC_AREGS+(3*4)
set EXC_A2,		EXC_AREGS+(2*4)
set EXC_A1,		EXC_AREGS+(1*4)
set EXC_A0,		EXC_AREGS+(0*4)
set EXC_D7,		EXC_DREGS+(7*4)
set EXC_D6,		EXC_DREGS+(6*4)
set EXC_D5,		EXC_DREGS+(5*4)
set EXC_D4,		EXC_DREGS+(4*4)
set EXC_D3,		EXC_DREGS+(3*4)
set EXC_D2,		EXC_DREGS+(2*4)
set EXC_D1,		EXC_DREGS+(1*4)
set EXC_D0,		EXC_DREGS+(0*4)

set EXC_FP0, 		EXC_FPREGS+(0*12)	# offset of saved fp0
set EXC_FP1, 		EXC_FPREGS+(1*12)	# offset of saved fp1
set EXC_FP2, 		EXC_FPREGS+(2*12)	# offset of saved fp2 (not used)

set FP_SCR1, 		LV+80			# fp scratch 1
set FP_SCR1_EX, 	FP_SCR1+0
set FP_SCR1_SGN,	FP_SCR1+2
set FP_SCR1_HI, 	FP_SCR1+4
set FP_SCR1_LO, 	FP_SCR1+8

set FP_SCR0, 		LV+68			# fp scratch 0
set FP_SCR0_EX, 	FP_SCR0+0
set FP_SCR0_SGN,	FP_SCR0+2
set FP_SCR0_HI, 	FP_SCR0+4
set FP_SCR0_LO, 	FP_SCR0+8

set FP_DST, 		LV+56			# fp destination operand
set FP_DST_EX, 		FP_DST+0
set FP_DST_SGN,		FP_DST+2
set FP_DST_HI, 		FP_DST+4
set FP_DST_LO, 		FP_DST+8

set FP_SRC, 		LV+44			# fp source operand
set FP_SRC_EX, 		FP_SRC+0
set FP_SRC_SGN,		FP_SRC+2
set FP_SRC_HI, 		FP_SRC+4
set FP_SRC_LO, 		FP_SRC+8

set USER_FPIAR,		LV+40			# FP instr address register

set USER_FPSR,		LV+36			# FP status register
set FPSR_CC,		USER_FPSR+0		# FPSR condition codes
set FPSR_QBYTE,		USER_FPSR+1		# FPSR qoutient byte
set FPSR_EXCEPT,	USER_FPSR+2		# FPSR exception status byte
set FPSR_AEXCEPT,	USER_FPSR+3		# FPSR accrued exception byte

set USER_FPCR,		LV+32			# FP control register
set FPCR_ENABLE,	USER_FPCR+2		# FPCR exception enable
set FPCR_MODE,		USER_FPCR+3		# FPCR rounding mode control

set L_SCR3,		LV+28			# integer scratch 3
set L_SCR2,		LV+24			# integer scratch 2
set L_SCR1,		LV+20			# integer scratch 1

set STORE_FLG,		LV+19			# flag: operand store (ie. not fcmp/ftst)

set EXC_TEMP2,		LV+24			# temporary space
set EXC_TEMP,		LV+16			# temporary space

set DTAG,		LV+15			# destination operand type
set STAG, 		LV+14			# source operand type

set SPCOND_FLG,		LV+10			# flag: special case (see below)

set EXC_CC,		LV+8			# saved condition codes
set EXC_EXTWPTR,	LV+4			# saved current PC (active)
set EXC_EXTWORD,	LV+2			# saved extension word
set EXC_CMDREG,		LV+2			# saved extension word
set EXC_OPWORD,		LV+0			# saved operation word

################################

# Helpful macros

set FTEMP,		0			# offsets within an
set FTEMP_EX, 		0			# extended precision
set FTEMP_SGN,		2			# value saved in memory.
set FTEMP_HI, 		4
set FTEMP_LO, 		8
set FTEMP_GRS,		12

set LOCAL,		0			# offsets within an
set LOCAL_EX, 		0			# extended precision 
set LOCAL_SGN,		2			# value saved in memory.
set LOCAL_HI, 		4
set LOCAL_LO, 		8
set LOCAL_GRS,		12

set DST,		0			# offsets within an
set DST_EX,		0			# extended precision
set DST_HI,		4			# value saved in memory.
set DST_LO,		8

set SRC,		0			# offsets within an
set SRC_EX,		0			# extended precision
set SRC_HI,		4			# value saved in memory.
set SRC_LO,		8

set SGL_LO,		0x3f81			# min sgl prec exponent
set SGL_HI,		0x407e			# max sgl prec exponent
set DBL_LO,		0x3c01			# min dbl prec exponent
set DBL_HI,		0x43fe			# max dbl prec exponent
set EXT_LO,		0x0			# min ext prec exponent
set EXT_HI,		0x7ffe			# max ext prec exponent

set EXT_BIAS,		0x3fff			# extended precision bias
set SGL_BIAS,		0x007f			# single precision bias
set DBL_BIAS,		0x03ff			# double precision bias

set NORM,		0x00			# operand type for STAG/DTAG
set ZERO,		0x01			# operand type for STAG/DTAG
set INF,		0x02			# operand type for STAG/DTAG
set QNAN,		0x03			# operand type for STAG/DTAG
set DENORM,		0x04			# operand type for STAG/DTAG
set SNAN,		0x05			# operand type for STAG/DTAG
set UNNORM,		0x06			# operand type for STAG/DTAG

##################
# FPSR/FPCR bits #
##################
set neg_bit,		0x3			# negative result
set z_bit,		0x2			# zero result
set inf_bit,		0x1			# infinite result
set nan_bit,		0x0			# NAN result

set q_sn_bit,		0x7			# sign bit of quotient byte

set bsun_bit,		7			# branch on unordered
set snan_bit,		6			# signalling NAN
set operr_bit,		5			# operand error
set ovfl_bit,		4			# overflow
set unfl_bit,		3			# underflow
set dz_bit,		2			# divide by zero
set inex2_bit,		1			# inexact result 2
set inex1_bit,		0			# inexact result 1

set aiop_bit,		7			# accrued inexact operation bit
set aovfl_bit,		6			# accrued overflow bit
set aunfl_bit,		5			# accrued underflow bit
set adz_bit,		4			# accrued dz bit
set ainex_bit,		3			# accrued inexact bit

#############################
# FPSR individual bit masks #
#############################
set neg_mask,		0x08000000		# negative bit mask (lw)
set inf_mask,		0x02000000		# infinity bit mask (lw)
set z_mask,		0x04000000		# zero bit mask (lw)
set nan_mask,		0x01000000		# nan bit mask (lw)

set neg_bmask,		0x08			# negative bit mask (byte)
set inf_bmask,		0x02			# infinity bit mask (byte)
set z_bmask,		0x04			# zero bit mask (byte)
set nan_bmask,		0x01			# nan bit mask (byte)

set bsun_mask,		0x00008000		# bsun exception mask
set snan_mask,		0x00004000		# snan exception mask
set operr_mask,		0x00002000		# operr exception mask
set ovfl_mask,		0x00001000		# overflow exception mask
set unfl_mask,		0x00000800		# underflow exception mask
set dz_mask,		0x00000400		# dz exception mask
set inex2_mask,		0x00000200		# inex2 exception mask
set inex1_mask,		0x00000100		# inex1 exception mask

set aiop_mask,		0x00000080		# accrued illegal operation
set aovfl_mask,		0x00000040		# accrued overflow
set aunfl_mask,		0x00000020		# accrued underflow
set adz_mask,		0x00000010		# accrued divide by zero
set ainex_mask,		0x00000008		# accrued inexact

######################################
# FPSR combinations used in the FPSP #
######################################
set dzinf_mask,		inf_mask+dz_mask+adz_mask
set opnan_mask,		nan_mask+operr_mask+aiop_mask
set nzi_mask,		0x01ffffff 		#clears N, Z, and I
set unfinx_mask,	unfl_mask+inex2_mask+aunfl_mask+ainex_mask
set unf2inx_mask,	unfl_mask+inex2_mask+ainex_mask
set ovfinx_mask,	ovfl_mask+inex2_mask+aovfl_mask+ainex_mask
set inx1a_mask,		inex1_mask+ainex_mask
set inx2a_mask,		inex2_mask+ainex_mask
set snaniop_mask, 	nan_mask+snan_mask+aiop_mask
set snaniop2_mask,	snan_mask+aiop_mask
set naniop_mask,	nan_mask+aiop_mask
set neginf_mask,	neg_mask+inf_mask
set infaiop_mask, 	inf_mask+aiop_mask
set negz_mask,		neg_mask+z_mask
set opaop_mask,		operr_mask+aiop_mask
set unfl_inx_mask,	unfl_mask+aunfl_mask+ainex_mask
set ovfl_inx_mask,	ovfl_mask+aovfl_mask+ainex_mask

#########
# misc. #
#########
set rnd_stky_bit,	29			# stky bit pos in longword

set sign_bit,		0x7			# sign bit
set signan_bit,		0x6			# signalling nan bit

set sgl_thresh,		0x3f81			# minimum sgl exponent
set dbl_thresh,		0x3c01			# minimum dbl exponent

set x_mode,		0x0			# extended precision
set s_mode,		0x4			# single precision
set d_mode,		0x8			# double precision

set rn_mode,		0x0			# round-to-nearest
set rz_mode,		0x1			# round-to-zero
set rm_mode,		0x2			# round-tp-minus-infinity
set rp_mode,		0x3			# round-to-plus-infinity

set mantissalen,	64			# length of mantissa in bits

set BYTE,		1			# len(byte) == 1 byte
set WORD, 		2			# len(word) == 2 bytes
set LONG, 		4			# len(longword) == 2 bytes

set BSUN_VEC,		0xc0			# bsun    vector offset
set INEX_VEC,		0xc4			# inexact vector offset
set DZ_VEC,		0xc8			# dz      vector offset
set UNFL_VEC,		0xcc			# unfl    vector offset
set OPERR_VEC,		0xd0			# operr   vector offset
set OVFL_VEC,		0xd4			# ovfl    vector offset
set SNAN_VEC,		0xd8			# snan    vector offset

###########################
# SPecial CONDition FLaGs #
###########################
set ftrapcc_flg,	0x01			# flag bit: ftrapcc exception
set fbsun_flg,		0x02			# flag bit: bsun exception
set mia7_flg,		0x04			# flag bit: (a7)+ <ea>
set mda7_flg,		0x08			# flag bit: -(a7) <ea>
set fmovm_flg,		0x40			# flag bit: fmovm instruction
set immed_flg,		0x80			# flag bit: &<data> <ea>

set ftrapcc_bit,	0x0
set fbsun_bit,		0x1
set mia7_bit,		0x2
set mda7_bit,		0x3
set immed_bit,		0x7

##################################
# TRANSCENDENTAL "LAST-OP" FLAGS #
##################################
set FMUL_OP,		0x0			# fmul instr performed last
set FDIV_OP,		0x1			# fdiv performed last
set FADD_OP,		0x2			# fadd performed last
set FMOV_OP,		0x3			# fmov performed last

#############
# CONSTANTS #
#############
T1:	long		0x40C62D38,0xD3D64634	# 16381 LOG2 LEAD
T2:	long		0x3D6F90AE,0xB1E75CC7	# 16381 LOG2 TRAIL

PI:	long		0x40000000,0xC90FDAA2,0x2168C235,0x00000000
PIBY2:	long		0x3FFF0000,0xC90FDAA2,0x2168C235,0x00000000

TWOBYPI:
	long		0x3FE45F30,0x6DC9C883

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_ovfl(): 060FPSP entry point for FP Overflow exception.	#
#									#
#	This handler should be the first code executed upon taking the	#
#	FP Overflow exception in an operating system.			#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read instruction longword			#
#	fix_skewed_ops() - adjust src operand in fsave frame		#
#	set_tag_x() - determine optype of src/dst operands		#
#	store_fpreg() - store opclass 0 or 2 result to FP regfile	#
#	unnorm_fix() - change UNNORM operands to NORM or ZERO		#
#	load_fpn2() - load dst operand from FP regfile			#
#	fout() - emulate an opclass 3 instruction			#
#	tbl_unsupp - add of table of emulation routines for opclass 0,2	#
#	_fpsp_done() - "callout" for 060FPSP exit (all work done!)	#
#	_real_ovfl() - "callout" for Overflow exception enabled code	#
#	_real_inex() - "callout" for Inexact exception enabled code	#
#	_real_trace() - "callout" for Trace exception code		#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the FP Ovfl exception stack frame	#
#	- The fsave frame contains the source operand			#
# 									#
# OUTPUT **************************************************************	#
#	Overflow Exception enabled:					#
#	- The system stack is unchanged					#
#	- The fsave frame contains the adjusted src op for opclass 0,2	#
#	Overflow Exception disabled:					#
#	- The system stack is unchanged					#
#	- The "exception present" flag in the fsave frame is cleared	#
#									#
# ALGORITHM ***********************************************************	#
#	On the 060, if an FP overflow is present as the result of any	#
# instruction, the 060 will take an overflow exception whether the 	#
# exception is enabled or disabled in the FPCR. For the disabled case, 	#
# This handler emulates the instruction to determine what the correct	#
# default result should be for the operation. This default result is	#
# then stored in either the FP regfile, data regfile, or memory. 	#
# Finally, the handler exits through the "callout" _fpsp_done() 	#
# denoting that no exceptional conditions exist within the machine.	#
# 	If the exception is enabled, then this handler must create the	#
# exceptional operand and plave it in the fsave state frame, and store	#
# the default result (only if the instruction is opclass 3). For 	#
# exceptions enabled, this handler must exit through the "callout" 	#
# _real_ovfl() so that the operating system enabled overflow handler	#
# can handle this case.							#
#	Two other conditions exist. First, if overflow was disabled 	#
# but the inexact exception was enabled, this handler must exit 	#
# through the "callout" _real_inex() regardless of whether the result	#
# was inexact.								#
#	Also, in the case of an opclass three instruction where 	#
# overflow was disabled and the trace exception was enabled, this	#
# handler must exit through the "callout" _real_trace().		#
#									#
#########################################################################

	global		_fpsp_ovfl
_fpsp_ovfl:

#$#	sub.l		&24,%sp			# make room for src/dst

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	fsave		FP_SRC(%a6)		# grab the "busy" frame

 	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
 	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

# the FPIAR holds the "current PC" of the faulting instruction
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)

##############################################################################

	btst		&0x5,EXC_CMDREG(%a6)	# is instr an fmove out?
	bne.w		fovfl_out


	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		fix_skewed_ops		# fix src op

# since, I believe, only NORMs and DENORMs can come through here,
# maybe we can avoid the subroutine call.
	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		set_tag_x		# tag the operand type
	mov.b		%d0,STAG(%a6)		# maybe NORM,DENORM

# bit five of the fp extension word separates the monadic and dyadic operations 
# that can pass through fpsp_ovfl(). remember that fcmp, ftst, and fsincos
# will never take this exception.
	btst		&0x5,1+EXC_CMDREG(%a6)	# is operation monadic or dyadic?
	beq.b		fovfl_extract		# monadic

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # dyadic; load dst reg
	bsr.l		load_fpn2		# load dst into FP_DST

	lea		FP_DST(%a6),%a0		# pass: ptr to dst op
	bsr.l		set_tag_x		# tag the operand type
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		fovfl_op2_done		# no
	bsr.l		unnorm_fix		# yes; convert to NORM,DENORM,or ZERO
fovfl_op2_done:
	mov.b		%d0,DTAG(%a6)		# save dst optype tag

fovfl_extract:

#$#	mov.l		FP_SRC_EX(%a6),TRAP_SRCOP_EX(%a6)
#$#	mov.l		FP_SRC_HI(%a6),TRAP_SRCOP_HI(%a6)
#$#	mov.l		FP_SRC_LO(%a6),TRAP_SRCOP_LO(%a6)
#$#	mov.l		FP_DST_EX(%a6),TRAP_DSTOP_EX(%a6)
#$#	mov.l		FP_DST_HI(%a6),TRAP_DSTOP_HI(%a6)
#$#	mov.l		FP_DST_LO(%a6),TRAP_DSTOP_LO(%a6)

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass rnd prec/mode

	mov.b		1+EXC_CMDREG(%a6),%d1
	andi.w		&0x007f,%d1		# extract extension

	andi.l		&0x00ff01ff,USER_FPSR(%a6) # zero all but accured field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

	lea		FP_SRC(%a6),%a0
	lea		FP_DST(%a6),%a1

# maybe we can make these entry points ONLY the OVFL entry points of each routine.
	mov.l		(tbl_unsupp.l,%pc,%d1.w*4),%d1 # fetch routine addr
	jsr		(tbl_unsupp.l,%pc,%d1.l*1)

# the operation has been emulated. the result is in fp0.
# the EXOP, if an exception occurred, is in fp1.
# we must save the default result regardless of whether
# traps are enabled or disabled.
	bfextu		EXC_CMDREG(%a6){&6:&3},%d0
	bsr.l		store_fpreg

# the exceptional possibilities we have left ourselves with are ONLY overflow
# and inexact. and, the inexact is such that overflow occurred and was disabled
# but inexact was enabled.
	btst		&ovfl_bit,FPCR_ENABLE(%a6)
	bne.b		fovfl_ovfl_on

	btst		&inex2_bit,FPCR_ENABLE(%a6)
	bne.b		fovfl_inex_on

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6
#$#	add.l		&24,%sp
	bra.l		_fpsp_done

# overflow is enabled AND overflow, of course, occurred. so, we have the EXOP
# in fp1. now, simply jump to _real_ovfl()!
fovfl_ovfl_on:
	fmovm.x		&0x40,FP_SRC(%a6)	# save EXOP (fp1) to stack

	mov.w		&0xe005,2+FP_SRC(%a6) 	# save exc status

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# do this after fmovm,other f<op>s!

	unlk		%a6

	bra.l		_real_ovfl

# overflow occurred but is disabled. meanwhile, inexact is enabled. therefore,
# we must jump to real_inex().
fovfl_inex_on:

	fmovm.x		&0x40,FP_SRC(%a6) 	# save EXOP (fp1) to stack

	mov.b		&0xc4,1+EXC_VOFF(%a6)	# vector offset = 0xc4
	mov.w		&0xe001,2+FP_SRC(%a6) 	# save exc status

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# do this after fmovm,other f<op>s!

	unlk		%a6

	bra.l		_real_inex

########################################################################
fovfl_out:


#$#	mov.l		FP_SRC_EX(%a6),TRAP_SRCOP_EX(%a6)
#$#	mov.l		FP_SRC_HI(%a6),TRAP_SRCOP_HI(%a6)
#$#	mov.l		FP_SRC_LO(%a6),TRAP_SRCOP_LO(%a6)

# the src operand is definitely a NORM(!), so tag it as such
	mov.b		&NORM,STAG(%a6)		# set src optype tag

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass rnd prec/mode

	and.l		&0xffff00ff,USER_FPSR(%a6) # zero all but accured field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

	lea		FP_SRC(%a6),%a0		# pass ptr to src operand

	bsr.l		fout

	btst		&ovfl_bit,FPCR_ENABLE(%a6)
	bne.w		fovfl_ovfl_on

	btst		&inex2_bit,FPCR_ENABLE(%a6)
	bne.w		fovfl_inex_on

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6
#$#	add.l		&24,%sp

	btst		&0x7,(%sp)		# is trace on?
	beq.l		_fpsp_done		# no

	fmov.l		%fpiar,0x8(%sp)		# "Current PC" is in FPIAR	
	mov.w		&0x2024,0x6(%sp)	# stk fmt = 0x2; voff = 0x024
	bra.l		_real_trace

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_unfl(): 060FPSP entry point for FP Underflow exception.	#
#									#
#	This handler should be the first code executed upon taking the	#
#	FP Underflow exception in an operating system.			#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read instruction longword			#
#	fix_skewed_ops() - adjust src operand in fsave frame		#
#	set_tag_x() - determine optype of src/dst operands		#
#	store_fpreg() - store opclass 0 or 2 result to FP regfile	#
#	unnorm_fix() - change UNNORM operands to NORM or ZERO		#
#	load_fpn2() - load dst operand from FP regfile			#
#	fout() - emulate an opclass 3 instruction			#
#	tbl_unsupp - add of table of emulation routines for opclass 0,2	#
#	_fpsp_done() - "callout" for 060FPSP exit (all work done!)	#
#	_real_ovfl() - "callout" for Overflow exception enabled code	#
#	_real_inex() - "callout" for Inexact exception enabled code	#
#	_real_trace() - "callout" for Trace exception code		#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the FP Unfl exception stack frame	#
#	- The fsave frame contains the source operand			#
# 									#
# OUTPUT **************************************************************	#
#	Underflow Exception enabled:					#
#	- The system stack is unchanged					#
#	- The fsave frame contains the adjusted src op for opclass 0,2	#
#	Underflow Exception disabled:					#
#	- The system stack is unchanged					#
#	- The "exception present" flag in the fsave frame is cleared	#
#									#
# ALGORITHM ***********************************************************	#
#	On the 060, if an FP underflow is present as the result of any	#
# instruction, the 060 will take an underflow exception whether the 	#
# exception is enabled or disabled in the FPCR. For the disabled case, 	#
# This handler emulates the instruction to determine what the correct	#
# default result should be for the operation. This default result is	#
# then stored in either the FP regfile, data regfile, or memory. 	#
# Finally, the handler exits through the "callout" _fpsp_done() 	#
# denoting that no exceptional conditions exist within the machine.	#
# 	If the exception is enabled, then this handler must create the	#
# exceptional operand and plave it in the fsave state frame, and store	#
# the default result (only if the instruction is opclass 3). For 	#
# exceptions enabled, this handler must exit through the "callout" 	#
# _real_unfl() so that the operating system enabled overflow handler	#
# can handle this case.							#
#	Two other conditions exist. First, if underflow was disabled 	#
# but the inexact exception was enabled and the result was inexact, 	#
# this handler must exit through the "callout" _real_inex().		#
# was inexact.								#
#	Also, in the case of an opclass three instruction where 	#
# underflow was disabled and the trace exception was enabled, this	#
# handler must exit through the "callout" _real_trace().		#
#									#
#########################################################################

	global		_fpsp_unfl
_fpsp_unfl:

#$#	sub.l		&24,%sp			# make room for src/dst

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	fsave		FP_SRC(%a6)		# grab the "busy" frame

 	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
 	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

# the FPIAR holds the "current PC" of the faulting instruction
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)	
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)

##############################################################################

	btst		&0x5,EXC_CMDREG(%a6)	# is instr an fmove out?
	bne.w		funfl_out


	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		fix_skewed_ops		# fix src op

	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		set_tag_x		# tag the operand type
	mov.b		%d0,STAG(%a6)		# maybe NORM,DENORM

# bit five of the fp ext word separates the monadic and dyadic operations 
# that can pass through fpsp_unfl(). remember that fcmp, and ftst
# will never take this exception.
	btst		&0x5,1+EXC_CMDREG(%a6)	# is op monadic or dyadic?
	beq.b		funfl_extract		# monadic

# now, what's left that's not dyadic is fsincos. we can distinguish it 
# from all dyadics by the '0110xxx pattern
	btst		&0x4,1+EXC_CMDREG(%a6)	# is op an fsincos?
	bne.b		funfl_extract		# yes

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # dyadic; load dst reg
	bsr.l		load_fpn2		# load dst into FP_DST

	lea		FP_DST(%a6),%a0		# pass: ptr to dst op
	bsr.l		set_tag_x		# tag the operand type
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		funfl_op2_done		# no
	bsr.l		unnorm_fix		# yes; convert to NORM,DENORM,or ZERO
funfl_op2_done:
	mov.b		%d0,DTAG(%a6)		# save dst optype tag

funfl_extract:

#$#	mov.l		FP_SRC_EX(%a6),TRAP_SRCOP_EX(%a6)
#$#	mov.l		FP_SRC_HI(%a6),TRAP_SRCOP_HI(%a6)
#$#	mov.l		FP_SRC_LO(%a6),TRAP_SRCOP_LO(%a6)
#$#	mov.l		FP_DST_EX(%a6),TRAP_DSTOP_EX(%a6)
#$#	mov.l		FP_DST_HI(%a6),TRAP_DSTOP_HI(%a6)
#$#	mov.l		FP_DST_LO(%a6),TRAP_DSTOP_LO(%a6)

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass rnd prec/mode

	mov.b		1+EXC_CMDREG(%a6),%d1
	andi.w		&0x007f,%d1		# extract extension

	andi.l		&0x00ff01ff,USER_FPSR(%a6)

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

	lea		FP_SRC(%a6),%a0
	lea		FP_DST(%a6),%a1

# maybe we can make these entry points ONLY the OVFL entry points of each routine.
	mov.l		(tbl_unsupp.l,%pc,%d1.w*4),%d1 # fetch routine addr
	jsr		(tbl_unsupp.l,%pc,%d1.l*1)

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0
	bsr.l		store_fpreg

# The `060 FPU multiplier hardware is such that if the result of a
# multiply operation is the smallest possible normalized number
# (0x00000000_80000000_00000000), then the machine will take an
# underflow exception. Since this is incorrect, we need to check
# if our emulation, after re-doing the operation, decided that
# no underflow was called for. We do these checks only in 
# funfl_{unfl,inex}_on() because w/ both exceptions disabled, this
# special case will simply exit gracefully with the correct result.

# the exceptional possibilities we have left ourselves with are ONLY overflow
# and inexact. and, the inexact is such that overflow occurred and was disabled
# but inexact was enabled.
	btst		&unfl_bit,FPCR_ENABLE(%a6)
	bne.b		funfl_unfl_on

funfl_chkinex:
	btst		&inex2_bit,FPCR_ENABLE(%a6)
	bne.b		funfl_inex_on

funfl_exit:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6
#$#	add.l		&24,%sp
	bra.l		_fpsp_done

# overflow is enabled AND overflow, of course, occurred. so, we have the EXOP
# in fp1 (don't forget to save fp0). what to do now?
# well, we simply have to get to go to _real_unfl()!
funfl_unfl_on:

# The `060 FPU multiplier hardware is such that if the result of a
# multiply operation is the smallest possible normalized number
# (0x00000000_80000000_00000000), then the machine will take an
# underflow exception. Since this is incorrect, we check here to see
# if our emulation, after re-doing the operation, decided that
# no underflow was called for.
	btst		&unfl_bit,FPSR_EXCEPT(%a6)
	beq.w		funfl_chkinex

funfl_unfl_on2:
	fmovm.x		&0x40,FP_SRC(%a6)	# save EXOP (fp1) to stack

	mov.w		&0xe003,2+FP_SRC(%a6) 	# save exc status

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# do this after fmovm,other f<op>s!

	unlk		%a6

	bra.l		_real_unfl

# undeflow occurred but is disabled. meanwhile, inexact is enabled. therefore,
# we must jump to real_inex().
funfl_inex_on:

# The `060 FPU multiplier hardware is such that if the result of a
# multiply operation is the smallest possible normalized number
# (0x00000000_80000000_00000000), then the machine will take an
# underflow exception. 
# But, whether bogus or not, if inexact is enabled AND it occurred,
# then we have to branch to real_inex.

	btst		&inex2_bit,FPSR_EXCEPT(%a6)
	beq.w		funfl_exit

funfl_inex_on2:

	fmovm.x		&0x40,FP_SRC(%a6) 	# save EXOP to stack

	mov.b		&0xc4,1+EXC_VOFF(%a6)	# vector offset = 0xc4
	mov.w		&0xe001,2+FP_SRC(%a6) 	# save exc status

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# do this after fmovm,other f<op>s!

	unlk		%a6

	bra.l		_real_inex

#######################################################################
funfl_out:


#$#	mov.l		FP_SRC_EX(%a6),TRAP_SRCOP_EX(%a6)
#$#	mov.l		FP_SRC_HI(%a6),TRAP_SRCOP_HI(%a6)
#$#	mov.l		FP_SRC_LO(%a6),TRAP_SRCOP_LO(%a6)

# the src operand is definitely a NORM(!), so tag it as such
	mov.b		&NORM,STAG(%a6)		# set src optype tag

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass rnd prec/mode

	and.l		&0xffff00ff,USER_FPSR(%a6) # zero all but accured field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

	lea		FP_SRC(%a6),%a0		# pass ptr to src operand

	bsr.l		fout

	btst		&unfl_bit,FPCR_ENABLE(%a6)
	bne.w		funfl_unfl_on2

	btst		&inex2_bit,FPCR_ENABLE(%a6)
	bne.w		funfl_inex_on2

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6
#$#	add.l		&24,%sp

	btst		&0x7,(%sp)		# is trace on?
	beq.l		_fpsp_done		# no

	fmov.l		%fpiar,0x8(%sp)		# "Current PC" is in FPIAR
	mov.w		&0x2024,0x6(%sp)	# stk fmt = 0x2; voff = 0x024
	bra.l		_real_trace

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_unsupp(): 060FPSP entry point for FP "Unimplemented	#
#		        Data Type" exception.				#
#									#
#	This handler should be the first code executed upon taking the	#
#	FP Unimplemented Data Type exception in an operating system.	#
#									#
# XREF ****************************************************************	#
#	_imem_read_{word,long}() - read instruction word/longword	#
#	fix_skewed_ops() - adjust src operand in fsave frame		#
#	set_tag_x() - determine optype of src/dst operands		#
#	store_fpreg() - store opclass 0 or 2 result to FP regfile	#
#	unnorm_fix() - change UNNORM operands to NORM or ZERO		#
#	load_fpn2() - load dst operand from FP regfile			#
#	load_fpn1() - load src operand from FP regfile			#
#	fout() - emulate an opclass 3 instruction			#
#	tbl_unsupp - add of table of emulation routines for opclass 0,2	#
#	_real_inex() - "callout" to operating system inexact handler	#
#	_fpsp_done() - "callout" for exit; work all done		#
#	_real_trace() - "callout" for Trace enabled exception		#
#	funimp_skew() - adjust fsave src ops to "incorrect" value	#
#	_real_snan() - "callout" for SNAN exception			#
#	_real_operr() - "callout" for OPERR exception			#
#	_real_ovfl() - "callout" for OVFL exception			#
#	_real_unfl() - "callout" for UNFL exception			#
#	get_packed() - fetch packed operand from memory			#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the "Unimp Data Type" stk frame	#
#	- The fsave frame contains the ssrc op (for UNNORM/DENORM)	#
# 									#
# OUTPUT **************************************************************	#
#	If Inexact exception (opclass 3):				#
#	- The system stack is changed to an Inexact exception stk frame	#
#	If SNAN exception (opclass 3):					#
#	- The system stack is changed to an SNAN exception stk frame	#
#	If OPERR exception (opclass 3):					#
#	- The system stack is changed to an OPERR exception stk frame	#
#	If OVFL exception (opclass 3):					#
#	- The system stack is changed to an OVFL exception stk frame	#
#	If UNFL exception (opclass 3):					#
#	- The system stack is changed to an UNFL exception stack frame	#
#	If Trace exception enabled:					#
#	- The system stack is changed to a Trace exception stack frame	#
#	Else: (normal case)						#
#	- Correct result has been stored as appropriate			#
#									#
# ALGORITHM ***********************************************************	#
#	Two main instruction types can enter here: (1) DENORM or UNNORM	#
# unimplemented data types. These can be either opclass 0,2 or 3 	#
# instructions, and (2) PACKED unimplemented data format instructions	#
# also of opclasses 0,2, or 3.						#
#	For UNNORM/DENORM opclass 0 and 2, the handler fetches the src	#
# operand from the fsave state frame and the dst operand (if dyadic)	#
# from the FP register file. The instruction is then emulated by 	#
# choosing an emulation routine from a table of routines indexed by	#
# instruction type. Once the instruction has been emulated and result	#
# saved, then we check to see if any enabled exceptions resulted from	#
# instruction emulation. If none, then we exit through the "callout"	#
# _fpsp_done(). If there is an enabled FP exception, then we insert	#
# this exception into the FPU in the fsave state frame and then exit	#
# through _fpsp_done().							#
#	PACKED opclass 0 and 2 is similar in how the instruction is	#
# emulated and exceptions handled. The differences occur in how the	#
# handler loads the packed op (by calling get_packed() routine) and	#
# by the fact that a Trace exception could be pending for PACKED ops.	#
# If a Trace exception is pending, then the current exception stack	#
# frame is changed to a Trace exception stack frame and an exit is	#
# made through _real_trace().						#
#	For UNNORM/DENORM opclass 3, the actual move out to memory is	#
# performed by calling the routine fout(). If no exception should occur	#
# as the result of emulation, then an exit either occurs through	#
# _fpsp_done() or through _real_trace() if a Trace exception is pending	#
# (a Trace stack frame must be created here, too). If an FP exception	#
# should occur, then we must create an exception stack frame of that	#
# type and jump to either _real_snan(), _real_operr(), _real_inex(),	#
# _real_unfl(), or _real_ovfl() as appropriate. PACKED opclass 3 	#
# emulation is performed in a similar manner.				#
#									#
#########################################################################

#
# (1) DENORM and UNNORM (unimplemented) data types:
#
#				post-instruction
#				*****************
#				*      EA	*
#	 pre-instruction	*		*
# 	*****************	*****************
#	* 0x0 *  0x0dc  *	* 0x3 *  0x0dc  *
#	*****************	*****************
#	*     Next	*	*     Next	*
#	*      PC	*	*      PC	*
#	*****************	*****************
#	*      SR	*	*      SR	*
#	*****************	*****************
#
# (2) PACKED format (unsupported) opclasses two and three:
#	*****************
#	*      EA	*
#	*		*
#	*****************
#	* 0x2 *  0x0dc	*
#	*****************
#	*     Next	*
#	*      PC	*
#	*****************
#	*      SR	*
#	*****************
#
	global		_fpsp_unsupp
_fpsp_unsupp:

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	fsave		FP_SRC(%a6)		# save fp state

 	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
 	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

	btst		&0x5,EXC_SR(%a6)	# user or supervisor mode?
	bne.b		fu_s
fu_u:
	mov.l		%usp,%a0		# fetch user stack pointer
	mov.l		%a0,EXC_A7(%a6)		# save on stack
	bra.b		fu_cont
# if the exception is an opclass zero or two unimplemented data type
# exception, then the a7' calculated here is wrong since it doesn't
# stack an ea. however, we don't need an a7' for this case anyways.
fu_s:
	lea		0x4+EXC_EA(%a6),%a0	# load old a7'
	mov.l		%a0,EXC_A7(%a6)		# save on stack

fu_cont:

# the FPIAR holds the "current PC" of the faulting instruction
# the FPIAR should be set correctly for ALL exceptions passing through
# this point.
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)	# store OPWORD and EXTWORD

############################

	clr.b		SPCOND_FLG(%a6)		# clear special condition flag

# Separate opclass three (fpn-to-mem) ops since they have a different
# stack frame and protocol.
	btst		&0x5,EXC_CMDREG(%a6)	# is it an fmove out?
	bne.w		fu_out			# yes

# Separate packed opclass two instructions.
	bfextu		EXC_CMDREG(%a6){&0:&6},%d0
	cmpi.b		%d0,&0x13
	beq.w		fu_in_pack


# I'm not sure at this point what FPSR bits are valid for this instruction.
# so, since the emulation routines re-create them anyways, zero exception field
	andi.l		&0x00ff00ff,USER_FPSR(%a6) # zero exception field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

# Opclass two w/ memory-to-fpn operation will have an incorrect extended
# precision format if the src format was single or double and the 
# source data type was an INF, NAN, DENORM, or UNNORM
	lea		FP_SRC(%a6),%a0		# pass ptr to input
	bsr.l		fix_skewed_ops

# we don't know whether the src operand or the dst operand (or both) is the
# UNNORM or DENORM. call the function that tags the operand type. if the
# input is an UNNORM, then convert it to a NORM, DENORM, or ZERO.
	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		set_tag_x		# tag the operand type
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		fu_op2			# no
	bsr.l		unnorm_fix		# yes; convert to NORM,DENORM,or ZERO

fu_op2:
	mov.b		%d0,STAG(%a6)		# save src optype tag

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # dyadic; load dst reg

# bit five of the fp extension word separates the monadic and dyadic operations 
# at this point
	btst		&0x5,1+EXC_CMDREG(%a6)	# is operation monadic or dyadic?
	beq.b		fu_extract		# monadic
	cmpi.b		1+EXC_CMDREG(%a6),&0x3a	# is operation an ftst?
	beq.b		fu_extract		# yes, so it's monadic, too

	bsr.l		load_fpn2		# load dst into FP_DST

	lea		FP_DST(%a6),%a0		# pass: ptr to dst op
	bsr.l		set_tag_x		# tag the operand type
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		fu_op2_done		# no
	bsr.l		unnorm_fix		# yes; convert to NORM,DENORM,or ZERO
fu_op2_done:
	mov.b		%d0,DTAG(%a6)		# save dst optype tag

fu_extract:
	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# fetch rnd mode/prec

	bfextu		1+EXC_CMDREG(%a6){&1:&7},%d1 # extract extension

	lea		FP_SRC(%a6),%a0
	lea		FP_DST(%a6),%a1

	mov.l		(tbl_unsupp.l,%pc,%d1.l*4),%d1 # fetch routine addr
	jsr		(tbl_unsupp.l,%pc,%d1.l*1)

#
# Exceptions in order of precedence:
# 	BSUN	: none
#	SNAN	: all dyadic ops
#	OPERR	: fsqrt(-NORM)
#	OVFL	: all except ftst,fcmp
#	UNFL	: all except ftst,fcmp
#	DZ	: fdiv
# 	INEX2	: all except ftst,fcmp
#	INEX1	: none (packed doesn't go through here)
#

# we determine the highest priority exception(if any) set by the
# emulation routine that has also been enabled by the user.
	mov.b		FPCR_ENABLE(%a6),%d0	# fetch exceptions set
	bne.b		fu_in_ena		# some are enabled

fu_in_cont:
# fcmp and ftst do not store any result.
	mov.b		1+EXC_CMDREG(%a6),%d0	# fetch extension
	andi.b		&0x38,%d0		# extract bits 3-5
	cmpi.b		%d0,&0x38		# is instr fcmp or ftst?
	beq.b		fu_in_exit		# yes

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # dyadic; load dst reg
	bsr.l		store_fpreg		# store the result

fu_in_exit:

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

	bra.l		_fpsp_done

fu_in_ena:
	and.b		FPSR_EXCEPT(%a6),%d0	# keep only ones enabled
	bfffo		%d0{&24:&8},%d0		# find highest priority exception
	bne.b		fu_in_exc		# there is at least one set

#
# No exceptions occurred that were also enabled. Now:
#
#   	if (OVFL && ovfl_disabled && inexact_enabled) {
#	    branch to _real_inex() (even if the result was exact!);
#     	} else {
#	    save the result in the proper fp reg (unless the op is fcmp or ftst);
#	    return;
#     	}
#
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # was overflow set?
	beq.b		fu_in_cont		# no
	
fu_in_ovflchk:
	btst		&inex2_bit,FPCR_ENABLE(%a6) # was inexact enabled?
	beq.b		fu_in_cont		# no
	bra.w		fu_in_exc_ovfl		# go insert overflow frame

#
# An exception occurred and that exception was enabled:
#
#	shift enabled exception field into lo byte of d0;
#	if (((INEX2 || INEX1) && inex_enabled && OVFL && ovfl_disabled) ||
#	    ((INEX2 || INEX1) && inex_enabled && UNFL && unfl_disabled)) {
#		/*
#		 * this is the case where we must call _real_inex() now or else
#		 * there will be no other way to pass it the exceptional operand
#		 */
#		call _real_inex();
#	} else {
#		restore exc state (SNAN||OPERR||OVFL||UNFL||DZ||INEX) into the FPU;
#	}
#	    		
fu_in_exc:
	subi.l		&24,%d0			# fix offset to be 0-8
	cmpi.b		%d0,&0x6		# is exception INEX? (6)
	bne.b		fu_in_exc_exit		# no

# the enabled exception was inexact
	btst		&unfl_bit,FPSR_EXCEPT(%a6) # did disabled underflow occur?
	bne.w		fu_in_exc_unfl		# yes
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did disabled overflow occur?
	bne.w		fu_in_exc_ovfl		# yes

# here, we insert the correct fsave status value into the fsave frame for the
# corresponding exception. the operand in the fsave frame should be the original 
# src operand.
fu_in_exc_exit:
	mov.l		%d0,-(%sp)		# save d0
	bsr.l		funimp_skew		# skew sgl or dbl inputs
	mov.l		(%sp)+,%d0		# restore d0

	mov.w		(tbl_except.b,%pc,%d0.w*2),2+FP_SRC(%a6) # create exc status

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# restore src op

	unlk		%a6

	bra.l		_fpsp_done

tbl_except:
	short		0xe000,0xe006,0xe004,0xe005
	short		0xe003,0xe002,0xe001,0xe001

fu_in_exc_unfl:
	mov.w		&0x4,%d0
	bra.b		fu_in_exc_exit
fu_in_exc_ovfl:
	mov.w		&0x03,%d0
	bra.b		fu_in_exc_exit

# If the input operand to this operation was opclass two and a single
# or double precision denorm, inf, or nan, the operand needs to be 
# "corrected" in order to have the proper equivalent extended precision 
# number.
	global		fix_skewed_ops
fix_skewed_ops:
	bfextu		EXC_CMDREG(%a6){&0:&6},%d0 # extract opclass,src fmt
	cmpi.b		%d0,&0x11		# is class = 2 & fmt = sgl?
	beq.b		fso_sgl			# yes
	cmpi.b		%d0,&0x15		# is class = 2 & fmt = dbl?
	beq.b		fso_dbl			# yes
	rts					# no

fso_sgl:
	mov.w		LOCAL_EX(%a0),%d0	# fetch src exponent
	andi.w		&0x7fff,%d0		# strip sign
	cmpi.w		%d0,&0x3f80		# is |exp| == $3f80?
	beq.b		fso_sgl_dnrm_zero	# yes
	cmpi.w		%d0,&0x407f		# no; is |exp| == $407f?
	beq.b		fso_infnan		# yes
	rts					# no

fso_sgl_dnrm_zero:
	andi.l		&0x7fffffff,LOCAL_HI(%a0) # clear j-bit
	beq.b		fso_zero		# it's a skewed zero
fso_sgl_dnrm:
# here, we count on norm not to alter a0...
	bsr.l		norm			# normalize mantissa
	neg.w		%d0			# -shft amt
	addi.w		&0x3f81,%d0		# adjust new exponent
	andi.w		&0x8000,LOCAL_EX(%a0) 	# clear old exponent
	or.w		%d0,LOCAL_EX(%a0)	# insert new exponent
	rts

fso_zero:
	andi.w		&0x8000,LOCAL_EX(%a0)	# clear bogus exponent
	rts

fso_infnan:
	andi.b		&0x7f,LOCAL_HI(%a0) 	# clear j-bit
	ori.w		&0x7fff,LOCAL_EX(%a0)	# make exponent = $7fff
	rts

fso_dbl:
	mov.w		LOCAL_EX(%a0),%d0	# fetch src exponent
	andi.w		&0x7fff,%d0		# strip sign
	cmpi.w		%d0,&0x3c00		# is |exp| == $3c00?
	beq.b		fso_dbl_dnrm_zero	# yes
	cmpi.w		%d0,&0x43ff		# no; is |exp| == $43ff?
	beq.b		fso_infnan		# yes
	rts					# no

fso_dbl_dnrm_zero:
	andi.l		&0x7fffffff,LOCAL_HI(%a0) # clear j-bit
	bne.b		fso_dbl_dnrm		# it's a skewed denorm
	tst.l		LOCAL_LO(%a0)		# is it a zero?
	beq.b		fso_zero		# yes
fso_dbl_dnrm:
# here, we count on norm not to alter a0...
	bsr.l		norm			# normalize mantissa
	neg.w		%d0			# -shft amt
	addi.w		&0x3c01,%d0		# adjust new exponent
	andi.w		&0x8000,LOCAL_EX(%a0) 	# clear old exponent
	or.w		%d0,LOCAL_EX(%a0)	# insert new exponent
	rts

#################################################################

# fmove out took an unimplemented data type exception.
# the src operand is in FP_SRC. Call _fout() to write out the result and
# to determine which exceptions, if any, to take.
fu_out:

# Separate packed move outs from the UNNORM and DENORM move outs.
	bfextu		EXC_CMDREG(%a6){&3:&3},%d0
	cmpi.b		%d0,&0x3
	beq.w		fu_out_pack
	cmpi.b		%d0,&0x7
	beq.w		fu_out_pack


# I'm not sure at this point what FPSR bits are valid for this instruction.
# so, since the emulation routines re-create them anyways, zero exception field.
# fmove out doesn't affect ccodes.
	and.l		&0xffff00ff,USER_FPSR(%a6) # zero exception field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

# the src can ONLY be a DENORM or an UNNORM! so, don't make any big subroutine
# call here. just figure out what it is...
	mov.w		FP_SRC_EX(%a6),%d0	# get exponent
	andi.w		&0x7fff,%d0		# strip sign
	beq.b		fu_out_denorm		# it's a DENORM

	lea		FP_SRC(%a6),%a0
	bsr.l		unnorm_fix		# yes; fix it

	mov.b		%d0,STAG(%a6)

	bra.b		fu_out_cont
fu_out_denorm:
	mov.b		&DENORM,STAG(%a6)
fu_out_cont:

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# fetch rnd mode/prec

	lea		FP_SRC(%a6),%a0		# pass ptr to src operand

	mov.l		(%a6),EXC_A6(%a6)	# in case a6 changes
	bsr.l		fout			# call fmove out routine

# Exceptions in order of precedence:
# 	BSUN	: none
#	SNAN	: none
#	OPERR	: fmove.{b,w,l} out of large UNNORM
#	OVFL	: fmove.{s,d}
#	UNFL	: fmove.{s,d,x}
#	DZ	: none
# 	INEX2	: all
#	INEX1	: none (packed doesn't travel through here)

# determine the highest priority exception(if any) set by the
# emulation routine that has also been enabled by the user.
	mov.b		FPCR_ENABLE(%a6),%d0	# fetch exceptions enabled
	bne.w		fu_out_ena		# some are enabled

fu_out_done:

	mov.l		EXC_A6(%a6),(%a6)	# in case a6 changed

# on extended precision opclass three instructions using pre-decrement or 
# post-increment addressing mode, the address register is not updated. is the
# address register was the stack pointer used from user mode, then let's update
# it here. if it was used from supervisor mode, then we have to handle this
# as a special case.
	btst		&0x5,EXC_SR(%a6)
	bne.b		fu_out_done_s

	mov.l		EXC_A7(%a6),%a0		# restore a7
	mov.l		%a0,%usp

fu_out_done_cont:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

	btst		&0x7,(%sp)		# is trace on?
	bne.b		fu_out_trace		# yes

	bra.l		_fpsp_done

# is the ea mode pre-decrement of the stack pointer from supervisor mode?
# ("fmov.x fpm,-(a7)") if so, 
fu_out_done_s:
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg
	bne.b		fu_out_done_cont

# the extended precision result is still in fp0. but, we need to save it
# somewhere on the stack until we can copy it to its final resting place.
# here, we're counting on the top of the stack to be the old place-holders
# for fp0/fp1 which have already been restored. that way, we can write
# over those destinations with the shifted stack frame.
	fmovm.x		&0x80,FP_SRC(%a6)	# put answer on stack

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.l		(%a6),%a6		# restore frame pointer

	mov.l		LOCAL_SIZE+EXC_SR(%sp),LOCAL_SIZE+EXC_SR-0xc(%sp)
	mov.l		LOCAL_SIZE+2+EXC_PC(%sp),LOCAL_SIZE+2+EXC_PC-0xc(%sp)

# now, copy the result to the proper place on the stack
	mov.l		LOCAL_SIZE+FP_SRC_EX(%sp),LOCAL_SIZE+EXC_SR+0x0(%sp)
	mov.l		LOCAL_SIZE+FP_SRC_HI(%sp),LOCAL_SIZE+EXC_SR+0x4(%sp)
	mov.l		LOCAL_SIZE+FP_SRC_LO(%sp),LOCAL_SIZE+EXC_SR+0x8(%sp)

	add.l		&LOCAL_SIZE-0x8,%sp

	btst		&0x7,(%sp)
	bne.b		fu_out_trace

	bra.l		_fpsp_done

fu_out_ena:
	and.b		FPSR_EXCEPT(%a6),%d0	# keep only ones enabled
	bfffo		%d0{&24:&8},%d0		# find highest priority exception
	bne.b		fu_out_exc		# there is at least one set

# no exceptions were set. 
# if a disabled overflow occurred and inexact was enabled but the result
# was exact, then a branch to _real_inex() is made.
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # was overflow set?
	beq.w		fu_out_done		# no

fu_out_ovflchk:
	btst		&inex2_bit,FPCR_ENABLE(%a6) # was inexact enabled?
	beq.w		fu_out_done		# no
	bra.w		fu_inex			# yes

#
# The fp move out that took the "Unimplemented Data Type" exception was
# being traced. Since the stack frames are similar, get the "current" PC
# from FPIAR and put it in the trace stack frame then jump to _real_trace().
#
#		  UNSUPP FRAME		   TRACE FRAME
# 		*****************	*****************
#		*      EA	*	*    Current	*
#		*		*	*      PC	*
#		*****************	*****************
#		* 0x3 *  0x0dc	*	* 0x2 *  0x024	*
#		*****************	*****************
#		*     Next	*	*     Next	*
#		*      PC	*	*      PC	*
#		*****************	*****************
#		*      SR	*	*      SR	*
#		*****************	*****************
#
fu_out_trace:
	mov.w		&0x2024,0x6(%sp)
	fmov.l		%fpiar,0x8(%sp)
	bra.l		_real_trace

# an exception occurred and that exception was enabled. 	
fu_out_exc:
	subi.l		&24,%d0			# fix offset to be 0-8

# we don't mess with the existing fsave frame. just re-insert it and
# jump to the "_real_{}()" handler...
	mov.w		(tbl_fu_out.b,%pc,%d0.w*2),%d0
	jmp		(tbl_fu_out.b,%pc,%d0.w*1)

	swbeg		&0x8
tbl_fu_out:
	short		tbl_fu_out	- tbl_fu_out	# BSUN can't happen
	short		tbl_fu_out 	- tbl_fu_out	# SNAN can't happen
	short		fu_operr	- tbl_fu_out	# OPERR
	short		fu_ovfl 	- tbl_fu_out	# OVFL
	short		fu_unfl 	- tbl_fu_out	# UNFL
	short		tbl_fu_out	- tbl_fu_out	# DZ can't happen
	short		fu_inex 	- tbl_fu_out	# INEX2
	short		tbl_fu_out	- tbl_fu_out	# INEX1 won't make it here

# for snan,operr,ovfl,unfl, src op is still in FP_SRC so just 
# frestore it.
fu_snan:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30d8,EXC_VOFF(%a6)	# vector offset = 0xd8
	mov.w		&0xe006,2+FP_SRC(%a6)

	frestore	FP_SRC(%a6)

	unlk		%a6


	bra.l		_real_snan

fu_operr:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30d0,EXC_VOFF(%a6)	# vector offset = 0xd0
	mov.w		&0xe004,2+FP_SRC(%a6)

	frestore	FP_SRC(%a6)

	unlk		%a6


	bra.l		_real_operr

fu_ovfl:
	fmovm.x		&0x40,FP_SRC(%a6)	# save EXOP to the stack

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30d4,EXC_VOFF(%a6)	# vector offset = 0xd4
	mov.w		&0xe005,2+FP_SRC(%a6)

	frestore	FP_SRC(%a6)		# restore EXOP

	unlk		%a6

	bra.l		_real_ovfl

# underflow can happen for extended precision. extended precision opclass
# three instruction exceptions don't update the stack pointer. so, if the
# exception occurred from user mode, then simply update a7 and exit normally.
# if the exception occurred from supervisor mode, check if 
fu_unfl:
	mov.l		EXC_A6(%a6),(%a6)	# restore a6

	btst		&0x5,EXC_SR(%a6)
	bne.w		fu_unfl_s

	mov.l		EXC_A7(%a6),%a0		# restore a7 whether we need
	mov.l		%a0,%usp		# to or not...
	
fu_unfl_cont:
	fmovm.x		&0x40,FP_SRC(%a6)	# save EXOP to the stack

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30cc,EXC_VOFF(%a6)	# vector offset = 0xcc
	mov.w		&0xe003,2+FP_SRC(%a6)

	frestore	FP_SRC(%a6)		# restore EXOP

	unlk		%a6

	bra.l		_real_unfl

fu_unfl_s:
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg # was the <ea> mode -(sp)?
	bne.b		fu_unfl_cont

# the extended precision result is still in fp0. but, we need to save it
# somewhere on the stack until we can copy it to its final resting place
# (where the exc frame is currently). make sure it's not at the top of the
# frame or it will get overwritten when the exc stack frame is shifted "down".
	fmovm.x		&0x80,FP_SRC(%a6)	# put answer on stack
	fmovm.x		&0x40,FP_DST(%a6)	# put EXOP on stack

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30cc,EXC_VOFF(%a6)	# vector offset = 0xcc
	mov.w		&0xe003,2+FP_DST(%a6)

	frestore	FP_DST(%a6)		# restore EXOP

	mov.l		(%a6),%a6		# restore frame pointer

	mov.l		LOCAL_SIZE+EXC_SR(%sp),LOCAL_SIZE+EXC_SR-0xc(%sp)
	mov.l		LOCAL_SIZE+2+EXC_PC(%sp),LOCAL_SIZE+2+EXC_PC-0xc(%sp)
	mov.l		LOCAL_SIZE+EXC_EA(%sp),LOCAL_SIZE+EXC_EA-0xc(%sp)

# now, copy the result to the proper place on the stack
	mov.l		LOCAL_SIZE+FP_SRC_EX(%sp),LOCAL_SIZE+EXC_SR+0x0(%sp)
	mov.l		LOCAL_SIZE+FP_SRC_HI(%sp),LOCAL_SIZE+EXC_SR+0x4(%sp)
	mov.l		LOCAL_SIZE+FP_SRC_LO(%sp),LOCAL_SIZE+EXC_SR+0x8(%sp)

	add.l		&LOCAL_SIZE-0x8,%sp

	bra.l		_real_unfl

# fmove in and out enter here.
fu_inex:
	fmovm.x		&0x40,FP_SRC(%a6)	# save EXOP to the stack

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30c4,EXC_VOFF(%a6)	# vector offset = 0xc4
	mov.w		&0xe001,2+FP_SRC(%a6)

	frestore	FP_SRC(%a6)		# restore EXOP

	unlk		%a6


	bra.l		_real_inex

#########################################################################
#########################################################################
fu_in_pack:


# I'm not sure at this point what FPSR bits are valid for this instruction.
# so, since the emulation routines re-create them anyways, zero exception field
	andi.l		&0x0ff00ff,USER_FPSR(%a6) # zero exception field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

	bsr.l		get_packed		# fetch packed src operand

	lea		FP_SRC(%a6),%a0		# pass ptr to src
	bsr.l		set_tag_x		# set src optype tag

	mov.b		%d0,STAG(%a6)		# save src optype tag

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # dyadic; load dst reg

# bit five of the fp extension word separates the monadic and dyadic operations 
# at this point
	btst		&0x5,1+EXC_CMDREG(%a6)	# is operation monadic or dyadic?
	beq.b		fu_extract_p		# monadic
	cmpi.b		1+EXC_CMDREG(%a6),&0x3a	# is operation an ftst?
	beq.b		fu_extract_p		# yes, so it's monadic, too

	bsr.l		load_fpn2		# load dst into FP_DST

	lea		FP_DST(%a6),%a0		# pass: ptr to dst op
	bsr.l		set_tag_x		# tag the operand type
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		fu_op2_done_p		# no
	bsr.l		unnorm_fix		# yes; convert to NORM,DENORM,or ZERO
fu_op2_done_p:
	mov.b		%d0,DTAG(%a6)		# save dst optype tag

fu_extract_p:
	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# fetch rnd mode/prec

	bfextu		1+EXC_CMDREG(%a6){&1:&7},%d1 # extract extension

	lea		FP_SRC(%a6),%a0
	lea		FP_DST(%a6),%a1

	mov.l		(tbl_unsupp.l,%pc,%d1.l*4),%d1 # fetch routine addr
	jsr		(tbl_unsupp.l,%pc,%d1.l*1)

#
# Exceptions in order of precedence:
# 	BSUN	: none
#	SNAN	: all dyadic ops
#	OPERR	: fsqrt(-NORM)
#	OVFL	: all except ftst,fcmp
#	UNFL	: all except ftst,fcmp
#	DZ	: fdiv
# 	INEX2	: all except ftst,fcmp
#	INEX1	: all
#

# we determine the highest priority exception(if any) set by the
# emulation routine that has also been enabled by the user.
	mov.b		FPCR_ENABLE(%a6),%d0	# fetch exceptions enabled
	bne.w		fu_in_ena_p		# some are enabled

fu_in_cont_p:
# fcmp and ftst do not store any result.
	mov.b		1+EXC_CMDREG(%a6),%d0	# fetch extension
	andi.b		&0x38,%d0		# extract bits 3-5
	cmpi.b		%d0,&0x38		# is instr fcmp or ftst?
	beq.b		fu_in_exit_p		# yes

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # dyadic; load dst reg
	bsr.l		store_fpreg		# store the result

fu_in_exit_p:

	btst		&0x5,EXC_SR(%a6)	# user or supervisor?
	bne.w		fu_in_exit_s_p		# supervisor

	mov.l		EXC_A7(%a6),%a0		# update user a7
	mov.l		%a0,%usp

fu_in_exit_cont_p:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6			# unravel stack frame

	btst		&0x7,(%sp)		# is trace on?
	bne.w		fu_trace_p		# yes

	bra.l		_fpsp_done		# exit to os

# the exception occurred in supervisor mode. check to see if the
# addressing mode was (a7)+. if so, we'll need to shift the
# stack frame "up".
fu_in_exit_s_p:
	btst		&mia7_bit,SPCOND_FLG(%a6) # was ea mode (a7)+
	beq.b		fu_in_exit_cont_p	# no

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6			# unravel stack frame

# shift the stack frame "up". we don't really care about the <ea> field.
	mov.l		0x4(%sp),0x10(%sp)
	mov.l		0x0(%sp),0xc(%sp)
	add.l		&0xc,%sp

	btst		&0x7,(%sp)		# is trace on?
	bne.w		fu_trace_p		# yes

	bra.l		_fpsp_done		# exit to os

fu_in_ena_p:
	and.b		FPSR_EXCEPT(%a6),%d0	# keep only ones enabled & set
	bfffo		%d0{&24:&8},%d0		# find highest priority exception
	bne.b		fu_in_exc_p		# at least one was set

#
# No exceptions occurred that were also enabled. Now:
#
#   	if (OVFL && ovfl_disabled && inexact_enabled) {
#	    branch to _real_inex() (even if the result was exact!);
#     	} else {
#	    save the result in the proper fp reg (unless the op is fcmp or ftst);
#	    return;
#     	}
#
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # was overflow set?
	beq.w		fu_in_cont_p		# no
	
fu_in_ovflchk_p:
	btst		&inex2_bit,FPCR_ENABLE(%a6) # was inexact enabled?
	beq.w		fu_in_cont_p		# no
	bra.w		fu_in_exc_ovfl_p	# do _real_inex() now

#
# An exception occurred and that exception was enabled:
#
#	shift enabled exception field into lo byte of d0;
#	if (((INEX2 || INEX1) && inex_enabled && OVFL && ovfl_disabled) ||
#	    ((INEX2 || INEX1) && inex_enabled && UNFL && unfl_disabled)) {
#		/*
#		 * this is the case where we must call _real_inex() now or else
#		 * there will be no other way to pass it the exceptional operand
#		 */
#		call _real_inex();
#	} else {
#		restore exc state (SNAN||OPERR||OVFL||UNFL||DZ||INEX) into the FPU;
#	}
#	    		
fu_in_exc_p:
	subi.l		&24,%d0			# fix offset to be 0-8
	cmpi.b		%d0,&0x6		# is exception INEX? (6 or 7)
	blt.b		fu_in_exc_exit_p	# no

# the enabled exception was inexact
	btst		&unfl_bit,FPSR_EXCEPT(%a6) # did disabled underflow occur?
	bne.w		fu_in_exc_unfl_p	# yes
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did disabled overflow occur?
	bne.w		fu_in_exc_ovfl_p	# yes

# here, we insert the correct fsave status value into the fsave frame for the
# corresponding exception. the operand in the fsave frame should be the original 
# src operand.
# as a reminder for future predicted pain and agony, we are passing in fsave the
# "non-skewed" operand for cases of sgl and dbl src INFs,NANs, and DENORMs.
# this is INCORRECT for enabled SNAN which would give to the user the skewed SNAN!!!
fu_in_exc_exit_p:
	btst		&0x5,EXC_SR(%a6)	# user or supervisor?
	bne.w		fu_in_exc_exit_s_p	# supervisor

	mov.l		EXC_A7(%a6),%a0		# update user a7
	mov.l		%a0,%usp

fu_in_exc_exit_cont_p:
	mov.w		(tbl_except_p.b,%pc,%d0.w*2),2+FP_SRC(%a6)

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# restore src op

	unlk		%a6

	btst		&0x7,(%sp)		# is trace enabled?
	bne.w		fu_trace_p		# yes

	bra.l		_fpsp_done

tbl_except_p:
	short		0xe000,0xe006,0xe004,0xe005
	short		0xe003,0xe002,0xe001,0xe001

fu_in_exc_ovfl_p:
	mov.w		&0x3,%d0
	bra.w		fu_in_exc_exit_p

fu_in_exc_unfl_p:
	mov.w		&0x4,%d0
	bra.w		fu_in_exc_exit_p

fu_in_exc_exit_s_p:
	btst		&mia7_bit,SPCOND_FLG(%a6)
	beq.b		fu_in_exc_exit_cont_p

	mov.w		(tbl_except_p.b,%pc,%d0.w*2),2+FP_SRC(%a6)

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# restore src op

	unlk		%a6			# unravel stack frame

# shift stack frame "up". who cares about <ea> field.
	mov.l		0x4(%sp),0x10(%sp)
	mov.l		0x0(%sp),0xc(%sp)
	add.l		&0xc,%sp

	btst		&0x7,(%sp)		# is trace on?
	bne.b		fu_trace_p		# yes

	bra.l		_fpsp_done		# exit to os
	
#
# The opclass two PACKED instruction that took an "Unimplemented Data Type" 
# exception was being traced. Make the "current" PC the FPIAR and put it in the 
# trace stack frame then jump to _real_trace().
#					
#		  UNSUPP FRAME		   TRACE FRAME
#		*****************	*****************
#		*      EA	*	*    Current	*
#		*		*	*      PC	*
#		*****************	*****************
#		* 0x2 *	0x0dc	* 	* 0x2 *  0x024	*
#		*****************	*****************
#		*     Next	*	*     Next	*
#		*      PC	*      	*      PC	*
#		*****************	*****************
#		*      SR	*	*      SR	*
#		*****************	*****************
fu_trace_p:
	mov.w		&0x2024,0x6(%sp)
	fmov.l		%fpiar,0x8(%sp)

	bra.l		_real_trace

#########################################################
#########################################################
fu_out_pack:


# I'm not sure at this point what FPSR bits are valid for this instruction.
# so, since the emulation routines re-create them anyways, zero exception field.
# fmove out doesn't affect ccodes.
	and.l		&0xffff00ff,USER_FPSR(%a6) # zero exception field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0
	bsr.l		load_fpn1

# unlike other opclass 3, unimplemented data type exceptions, packed must be
# able to detect all operand types.
	lea		FP_SRC(%a6),%a0
	bsr.l		set_tag_x		# tag the operand type
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		fu_op2_p		# no
	bsr.l		unnorm_fix		# yes; convert to NORM,DENORM,or ZERO

fu_op2_p:
	mov.b		%d0,STAG(%a6)		# save src optype tag

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# fetch rnd mode/prec

	lea		FP_SRC(%a6),%a0		# pass ptr to src operand

	mov.l		(%a6),EXC_A6(%a6)	# in case a6 changes
	bsr.l		fout			# call fmove out routine

# Exceptions in order of precedence:
# 	BSUN	: no
#	SNAN	: yes
#	OPERR	: if ((k_factor > +17) || (dec. exp exceeds 3 digits))
#	OVFL	: no
#	UNFL	: no
#	DZ	: no
# 	INEX2	: yes
#	INEX1	: no

# determine the highest priority exception(if any) set by the
# emulation routine that has also been enabled by the user.
	mov.b		FPCR_ENABLE(%a6),%d0	# fetch exceptions enabled
	bne.w		fu_out_ena_p		# some are enabled

fu_out_exit_p:
	mov.l		EXC_A6(%a6),(%a6)	# restore a6

	btst		&0x5,EXC_SR(%a6)	# user or supervisor?
	bne.b		fu_out_exit_s_p		# supervisor

	mov.l		EXC_A7(%a6),%a0		# update user a7
	mov.l		%a0,%usp

fu_out_exit_cont_p:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6			# unravel stack frame

	btst		&0x7,(%sp)		# is trace on?
	bne.w		fu_trace_p		# yes

	bra.l		_fpsp_done		# exit to os

# the exception occurred in supervisor mode. check to see if the
# addressing mode was -(a7). if so, we'll need to shift the
# stack frame "down".
fu_out_exit_s_p:
	btst		&mda7_bit,SPCOND_FLG(%a6) # was ea mode -(a7)
	beq.b		fu_out_exit_cont_p	# no

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.l		(%a6),%a6		# restore frame pointer

	mov.l		LOCAL_SIZE+EXC_SR(%sp),LOCAL_SIZE+EXC_SR-0xc(%sp)
	mov.l		LOCAL_SIZE+2+EXC_PC(%sp),LOCAL_SIZE+2+EXC_PC-0xc(%sp)

# now, copy the result to the proper place on the stack
	mov.l		LOCAL_SIZE+FP_DST_EX(%sp),LOCAL_SIZE+EXC_SR+0x0(%sp)
	mov.l		LOCAL_SIZE+FP_DST_HI(%sp),LOCAL_SIZE+EXC_SR+0x4(%sp)
	mov.l		LOCAL_SIZE+FP_DST_LO(%sp),LOCAL_SIZE+EXC_SR+0x8(%sp)

	add.l		&LOCAL_SIZE-0x8,%sp

	btst		&0x7,(%sp)
	bne.w		fu_trace_p

	bra.l		_fpsp_done

fu_out_ena_p:
	and.b		FPSR_EXCEPT(%a6),%d0	# keep only ones enabled
	bfffo		%d0{&24:&8},%d0		# find highest priority exception
	beq.w		fu_out_exit_p

	mov.l		EXC_A6(%a6),(%a6)	# restore a6

# an exception occurred and that exception was enabled. 	
# the only exception possible on packed move out are INEX, OPERR, and SNAN.
fu_out_exc_p:
	cmpi.b		%d0,&0x1a
	bgt.w		fu_inex_p2
	beq.w		fu_operr_p

fu_snan_p:
	btst		&0x5,EXC_SR(%a6)
	bne.b		fu_snan_s_p

	mov.l		EXC_A7(%a6),%a0
	mov.l		%a0,%usp
	bra.w		fu_snan

fu_snan_s_p:
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg
	bne.w		fu_snan

# the instruction was "fmove.p fpn,-(a7)" from supervisor mode.
# the strategy is to move the exception frame "down" 12 bytes. then, we
# can store the default result where the exception frame was.
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30d8,EXC_VOFF(%a6)	# vector offset = 0xd0
	mov.w		&0xe006,2+FP_SRC(%a6) 	# set fsave status

	frestore	FP_SRC(%a6)		# restore src operand

	mov.l		(%a6),%a6		# restore frame pointer

	mov.l		LOCAL_SIZE+EXC_SR(%sp),LOCAL_SIZE+EXC_SR-0xc(%sp)
	mov.l		LOCAL_SIZE+2+EXC_PC(%sp),LOCAL_SIZE+2+EXC_PC-0xc(%sp)
	mov.l		LOCAL_SIZE+EXC_EA(%sp),LOCAL_SIZE+EXC_EA-0xc(%sp)

# now, we copy the default result to it's proper location
	mov.l		LOCAL_SIZE+FP_DST_EX(%sp),LOCAL_SIZE+0x4(%sp)
	mov.l		LOCAL_SIZE+FP_DST_HI(%sp),LOCAL_SIZE+0x8(%sp)
	mov.l		LOCAL_SIZE+FP_DST_LO(%sp),LOCAL_SIZE+0xc(%sp)

	add.l		&LOCAL_SIZE-0x8,%sp


	bra.l		_real_snan

fu_operr_p:
	btst		&0x5,EXC_SR(%a6)
	bne.w		fu_operr_p_s

	mov.l		EXC_A7(%a6),%a0
	mov.l		%a0,%usp
	bra.w		fu_operr

fu_operr_p_s:
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg
	bne.w		fu_operr

# the instruction was "fmove.p fpn,-(a7)" from supervisor mode.
# the strategy is to move the exception frame "down" 12 bytes. then, we
# can store the default result where the exception frame was.
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30d0,EXC_VOFF(%a6)	# vector offset = 0xd0
	mov.w		&0xe004,2+FP_SRC(%a6) 	# set fsave status

	frestore	FP_SRC(%a6)		# restore src operand

	mov.l		(%a6),%a6		# restore frame pointer

	mov.l		LOCAL_SIZE+EXC_SR(%sp),LOCAL_SIZE+EXC_SR-0xc(%sp)
	mov.l		LOCAL_SIZE+2+EXC_PC(%sp),LOCAL_SIZE+2+EXC_PC-0xc(%sp)
	mov.l		LOCAL_SIZE+EXC_EA(%sp),LOCAL_SIZE+EXC_EA-0xc(%sp)

# now, we copy the default result to it's proper location
	mov.l		LOCAL_SIZE+FP_DST_EX(%sp),LOCAL_SIZE+0x4(%sp)
	mov.l		LOCAL_SIZE+FP_DST_HI(%sp),LOCAL_SIZE+0x8(%sp)
	mov.l		LOCAL_SIZE+FP_DST_LO(%sp),LOCAL_SIZE+0xc(%sp)

	add.l		&LOCAL_SIZE-0x8,%sp


	bra.l		_real_operr

fu_inex_p2:
	btst		&0x5,EXC_SR(%a6)
	bne.w		fu_inex_s_p2

	mov.l		EXC_A7(%a6),%a0
	mov.l		%a0,%usp
	bra.w		fu_inex

fu_inex_s_p2:
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg
	bne.w		fu_inex

# the instruction was "fmove.p fpn,-(a7)" from supervisor mode.
# the strategy is to move the exception frame "down" 12 bytes. then, we
# can store the default result where the exception frame was.
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0/fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	mov.w		&0x30c4,EXC_VOFF(%a6) 	# vector offset = 0xc4
	mov.w		&0xe001,2+FP_SRC(%a6) 	# set fsave status

	frestore	FP_SRC(%a6)		# restore src operand

	mov.l		(%a6),%a6		# restore frame pointer

	mov.l		LOCAL_SIZE+EXC_SR(%sp),LOCAL_SIZE+EXC_SR-0xc(%sp)
	mov.l		LOCAL_SIZE+2+EXC_PC(%sp),LOCAL_SIZE+2+EXC_PC-0xc(%sp)
	mov.l		LOCAL_SIZE+EXC_EA(%sp),LOCAL_SIZE+EXC_EA-0xc(%sp)

# now, we copy the default result to it's proper location
	mov.l		LOCAL_SIZE+FP_DST_EX(%sp),LOCAL_SIZE+0x4(%sp)
	mov.l		LOCAL_SIZE+FP_DST_HI(%sp),LOCAL_SIZE+0x8(%sp)
	mov.l		LOCAL_SIZE+FP_DST_LO(%sp),LOCAL_SIZE+0xc(%sp)

	add.l		&LOCAL_SIZE-0x8,%sp


	bra.l		_real_inex

#########################################################################

#
# if we're stuffing a source operand back into an fsave frame then we
# have to make sure that for single or double source operands that the
# format stuffed is as weird as the hardware usually makes it.
#
	global		funimp_skew
funimp_skew:
	bfextu		EXC_EXTWORD(%a6){&3:&3},%d0 # extract src specifier
	cmpi.b		%d0,&0x1		# was src sgl?
	beq.b		funimp_skew_sgl		# yes
	cmpi.b		%d0,&0x5		# was src dbl?
	beq.b		funimp_skew_dbl		# yes
	rts

funimp_skew_sgl:
	mov.w		FP_SRC_EX(%a6),%d0	# fetch DENORM exponent
	andi.w		&0x7fff,%d0		# strip sign
	beq.b		funimp_skew_sgl_not
	cmpi.w		%d0,&0x3f80
	bgt.b		funimp_skew_sgl_not		
	neg.w		%d0			# make exponent negative
	addi.w		&0x3f81,%d0		# find amt to shift
	mov.l		FP_SRC_HI(%a6),%d1	# fetch DENORM hi(man)
	lsr.l		%d0,%d1			# shift it
	bset		&31,%d1			# set j-bit
	mov.l		%d1,FP_SRC_HI(%a6)	# insert new hi(man)
	andi.w		&0x8000,FP_SRC_EX(%a6)	# clear old exponent
	ori.w		&0x3f80,FP_SRC_EX(%a6)	# insert new "skewed" exponent
funimp_skew_sgl_not:
	rts

funimp_skew_dbl:
	mov.w		FP_SRC_EX(%a6),%d0	# fetch DENORM exponent
	andi.w		&0x7fff,%d0		# strip sign
	beq.b		funimp_skew_dbl_not
	cmpi.w		%d0,&0x3c00
	bgt.b		funimp_skew_dbl_not		

	tst.b		FP_SRC_EX(%a6)		# make "internal format"
	smi.b		0x2+FP_SRC(%a6)
	mov.w		%d0,FP_SRC_EX(%a6)	# insert exponent with cleared sign
	clr.l		%d0			# clear g,r,s
	lea		FP_SRC(%a6),%a0		# pass ptr to src op
	mov.w		&0x3c01,%d1		# pass denorm threshold
	bsr.l		dnrm_lp			# denorm it
	mov.w		&0x3c00,%d0		# new exponent
	tst.b		0x2+FP_SRC(%a6)		# is sign set?
	beq.b		fss_dbl_denorm_done	# no
	bset		&15,%d0			# set sign
fss_dbl_denorm_done:
	bset		&0x7,FP_SRC_HI(%a6)	# set j-bit
	mov.w		%d0,FP_SRC_EX(%a6)	# insert new exponent
funimp_skew_dbl_not:
	rts

#########################################################################
	global		_mem_write2
_mem_write2:
	btst		&0x5,EXC_SR(%a6)
	beq.l		_dmem_write
	mov.l		0x0(%a0),FP_DST_EX(%a6)
	mov.l		0x4(%a0),FP_DST_HI(%a6)
	mov.l		0x8(%a0),FP_DST_LO(%a6)
	clr.l		%d1
	rts

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_effadd(): 060FPSP entry point for FP "Unimplemented	#
#		     	effective address" exception.			#
#									#
#	This handler should be the first code executed upon taking the	#
#	FP Unimplemented Effective Address exception in an operating	#
#	system.								#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read instruction longword			#
#	fix_skewed_ops() - adjust src operand in fsave frame		#
#	set_tag_x() - determine optype of src/dst operands		#
#	store_fpreg() - store opclass 0 or 2 result to FP regfile	#
#	unnorm_fix() - change UNNORM operands to NORM or ZERO		#
#	load_fpn2() - load dst operand from FP regfile			#
#	tbl_unsupp - add of table of emulation routines for opclass 0,2	#
#	decbin() - convert packed data to FP binary data		#
#	_real_fpu_disabled() - "callout" for "FPU disabled" exception	#
#	_real_access() - "callout" for access error exception		#
#	_mem_read() - read extended immediate operand from memory	#
#	_fpsp_done() - "callout" for exit; work all done		#
#	_real_trace() - "callout" for Trace enabled exception		#
#	fmovm_dynamic() - emulate dynamic fmovm instruction		#
#	fmovm_ctrl() - emulate fmovm control instruction		#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the "Unimplemented <ea>" stk frame	#
# 									#
# OUTPUT **************************************************************	#
#	If access error:						#
#	- The system stack is changed to an access error stack frame	#
#	If FPU disabled:						#
#	- The system stack is changed to an FPU disabled stack frame	#
#	If Trace exception enabled:					#
#	- The system stack is changed to a Trace exception stack frame	#
#	Else: (normal case)						#
#	- None (correct result has been stored as appropriate)		#
#									#
# ALGORITHM ***********************************************************	#
#	This exception handles 3 types of operations:			#
# (1) FP Instructions using extended precision or packed immediate	#
#     addressing mode.							#
# (2) The "fmovm.x" instruction w/ dynamic register specification.	#
# (3) The "fmovm.l" instruction w/ 2 or 3 control registers.		#
#									#
#	For immediate data operations, the data is read in w/ a		#
# _mem_read() "callout", converted to FP binary (if packed), and used	#
# as the source operand to the instruction specified by the instruction	#
# word. If no FP exception should be reported ads a result of the 	#
# emulation, then the result is stored to the destination register and	#
# the handler exits through _fpsp_done(). If an enabled exc has been	#
# signalled as a result of emulation, then an fsave state frame		#
# corresponding to the FP exception type must be entered into the 060	#
# FPU before exiting. In either the enabled or disabled cases, we 	#
# must also check if a Trace exception is pending, in which case, we	#
# must create a Trace exception stack frame from the current exception	#
# stack frame. If no Trace is pending, we simply exit through		#
# _fpsp_done().								#
#	For "fmovm.x", call the routine fmovm_dynamic() which will 	#
# decode and emulate the instruction. No FP exceptions can be pending	#
# as a result of this operation emulation. A Trace exception can be	#
# pending, though, which means the current stack frame must be changed	#
# to a Trace stack frame and an exit made through _real_trace().	#
# For the case of "fmovm.x Dn,-(a7)", where the offending instruction	#
# was executed from supervisor mode, this handler must store the FP	#
# register file values to the system stack by itself since		#
# fmovm_dynamic() can't handle this. A normal exit is made through	#
# fpsp_done().								#
#	For "fmovm.l", fmovm_ctrl() is used to emulate the instruction.	#
# Again, a Trace exception may be pending and an exit made through	#
# _real_trace(). Else, a normal exit is made through _fpsp_done().	#
#									#
#	Before any of the above is attempted, it must be checked to	#
# see if the FPU is disabled. Since the "Unimp <ea>" exception is taken	#
# before the "FPU disabled" exception, but the "FPU disabled" exception	#
# has higher priority, we check the disabled bit in the PCR. If set,	#
# then we must create an 8 word "FPU disabled" exception stack frame	#
# from the current 4 word exception stack frame. This includes 		#
# reproducing the effective address of the instruction to put on the 	#
# new stack frame.							#
#									#
# 	In the process of all emulation work, if a _mem_read()		#
# "callout" returns a failing result indicating an access error, then	#
# we must create an access error stack frame from the current stack	#
# frame. This information includes a faulting address and a fault-	#
# status-longword. These are created within this handler.		#
#									#
#########################################################################

	global		_fpsp_effadd
_fpsp_effadd:

# This exception type takes priority over the "Line F Emulator"
# exception. Therefore, the FPU could be disabled when entering here.
# So, we must check to see if it's disabled and handle that case separately.
	mov.l		%d0,-(%sp)		# save d0
	movc		%pcr,%d0		# load proc cr
	btst		&0x1,%d0		# is FPU disabled?
	bne.w		iea_disabled		# yes
	mov.l		(%sp)+,%d0		# restore d0

	link		%a6,&-LOCAL_SIZE	# init stack frame

	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

# PC of instruction that took the exception is the PC in the frame
	mov.l		EXC_PC(%a6),EXC_EXTWPTR(%a6)

	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)	# store OPWORD and EXTWORD

#########################################################################

	tst.w		%d0			# is operation fmovem?
	bmi.w		iea_fmovm		# yes

#
# here, we will have:
# 	fabs	fdabs	fsabs		facos		fmod
#	fadd	fdadd	fsadd		fasin		frem
# 	fcmp				fatan		fscale
#	fdiv	fddiv	fsdiv		fatanh		fsin
#	fint				fcos		fsincos
#	fintrz				fcosh		fsinh
#	fmove	fdmove	fsmove		fetox		ftan
# 	fmul	fdmul	fsmul		fetoxm1		ftanh
#	fneg	fdneg	fsneg		fgetexp		ftentox
#	fsgldiv				fgetman		ftwotox
# 	fsglmul				flog10
# 	fsqrt				flog2
#	fsub	fdsub	fssub		flogn
#	ftst				flognp1
# which can all use f<op>.{x,p}
# so, now it's immediate data extended precision AND PACKED FORMAT!
#
iea_op:
	andi.l		&0x00ff00ff,USER_FPSR(%a6)

	btst		&0xa,%d0		# is src fmt x or p?
	bne.b		iea_op_pack		# packed


	mov.l		EXC_EXTWPTR(%a6),%a0	# pass: ptr to #<data>
	lea		FP_SRC(%a6),%a1		# pass: ptr to super addr
	mov.l		&0xc,%d0		# pass: 12 bytes
	bsr.l		_imem_read		# read extended immediate

	tst.l		%d1			# did ifetch fail?
	bne.w		iea_iacc		# yes

	bra.b		iea_op_setsrc

iea_op_pack:

	mov.l		EXC_EXTWPTR(%a6),%a0	# pass: ptr to #<data>
	lea		FP_SRC(%a6),%a1		# pass: ptr to super dst
	mov.l		&0xc,%d0		# pass: 12 bytes
	bsr.l		_imem_read		# read packed operand

	tst.l		%d1			# did ifetch fail?
	bne.w		iea_iacc		# yes

# The packed operand is an INF or a NAN if the exponent field is all ones.
	bfextu		FP_SRC(%a6){&1:&15},%d0	# get exp
	cmpi.w		%d0,&0x7fff		# INF or NAN?
	beq.b		iea_op_setsrc		# operand is an INF or NAN

# The packed operand is a zero if the mantissa is all zero, else it's
# a normal packed op.
	mov.b		3+FP_SRC(%a6),%d0	# get byte 4
	andi.b		&0x0f,%d0		# clear all but last nybble
	bne.b		iea_op_gp_not_spec	# not a zero
	tst.l		FP_SRC_HI(%a6)		# is lw 2 zero?
	bne.b		iea_op_gp_not_spec	# not a zero
	tst.l		FP_SRC_LO(%a6)		# is lw 3 zero?
	beq.b		iea_op_setsrc		# operand is a ZERO
iea_op_gp_not_spec:
	lea		FP_SRC(%a6),%a0		# pass: ptr to packed op
	bsr.l		decbin			# convert to extended
	fmovm.x		&0x80,FP_SRC(%a6)	# make this the srcop

iea_op_setsrc:
	addi.l		&0xc,EXC_EXTWPTR(%a6)	# update extension word pointer

# FP_SRC now holds the src operand.
	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		set_tag_x		# tag the operand type
	mov.b		%d0,STAG(%a6)		# could be ANYTHING!!!
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		iea_op_getdst		# no
	bsr.l		unnorm_fix		# yes; convert to NORM/DENORM/ZERO
	mov.b		%d0,STAG(%a6)		# set new optype tag
iea_op_getdst:
	clr.b		STORE_FLG(%a6)		# clear "store result" boolean

	btst		&0x5,1+EXC_CMDREG(%a6)	# is operation monadic or dyadic?
	beq.b		iea_op_extract		# monadic
	btst		&0x4,1+EXC_CMDREG(%a6)	# is operation fsincos,ftst,fcmp?
	bne.b		iea_op_spec		# yes

iea_op_loaddst:
	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # fetch dst regno
	bsr.l		load_fpn2		# load dst operand

	lea		FP_DST(%a6),%a0		# pass: ptr to dst op
	bsr.l		set_tag_x		# tag the operand type
	mov.b		%d0,DTAG(%a6)		# could be ANYTHING!!!
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		iea_op_extract		# no
	bsr.l		unnorm_fix		# yes; convert to NORM/DENORM/ZERO
	mov.b		%d0,DTAG(%a6)		# set new optype tag
	bra.b		iea_op_extract

# the operation is fsincos, ftst, or fcmp. only fcmp is dyadic
iea_op_spec:
	btst		&0x3,1+EXC_CMDREG(%a6)	# is operation fsincos?
	beq.b		iea_op_extract		# yes
# now, we're left with ftst and fcmp. so, first let's tag them so that they don't
# store a result. then, only fcmp will branch back and pick up a dst operand.
	st		STORE_FLG(%a6)		# don't store a final result
	btst		&0x1,1+EXC_CMDREG(%a6)	# is operation fcmp?
	beq.b		iea_op_loaddst		# yes	
	
iea_op_extract:
	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass: rnd mode,prec

	mov.b		1+EXC_CMDREG(%a6),%d1
	andi.w		&0x007f,%d1		# extract extension

	fmov.l		&0x0,%fpcr
	fmov.l		&0x0,%fpsr

	lea		FP_SRC(%a6),%a0
	lea		FP_DST(%a6),%a1

	mov.l		(tbl_unsupp.l,%pc,%d1.w*4),%d1 # fetch routine addr
	jsr		(tbl_unsupp.l,%pc,%d1.l*1)

#
# Exceptions in order of precedence:
#	BSUN	: none
#	SNAN	: all operations
#	OPERR	: all reg-reg or mem-reg operations that can normally operr
#	OVFL	: same as OPERR
#	UNFL	: same as OPERR
#	DZ	: same as OPERR
#	INEX2	: same as OPERR
#	INEX1	: all packed immediate operations
#

# we determine the highest priority exception(if any) set by the
# emulation routine that has also been enabled by the user.
	mov.b		FPCR_ENABLE(%a6),%d0	# fetch exceptions enabled
	bne.b		iea_op_ena		# some are enabled

# now, we save the result, unless, of course, the operation was ftst or fcmp.
# these don't save results.
iea_op_save:
	tst.b		STORE_FLG(%a6)		# does this op store a result?
	bne.b		iea_op_exit1		# exit with no frestore

iea_op_store:
	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # fetch dst regno
	bsr.l		store_fpreg		# store the result

iea_op_exit1:
	mov.l		EXC_PC(%a6),USER_FPIAR(%a6) # set FPIAR to "Current PC"
	mov.l		EXC_EXTWPTR(%a6),EXC_PC(%a6) # set "Next PC" in exc frame

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6			# unravel the frame

	btst		&0x7,(%sp)		# is trace on?
	bne.w		iea_op_trace		# yes

	bra.l		_fpsp_done		# exit to os

iea_op_ena:
	and.b		FPSR_EXCEPT(%a6),%d0	# keep only ones enable and set
	bfffo		%d0{&24:&8},%d0		# find highest priority exception
	bne.b		iea_op_exc		# at least one was set

# no exception occurred. now, did a disabled, exact overflow occur with inexact
# enabled? if so, then we have to stuff an overflow frame into the FPU.
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did overflow occur?
	beq.b		iea_op_save

iea_op_ovfl:
	btst		&inex2_bit,FPCR_ENABLE(%a6) # is inexact enabled?
	beq.b		iea_op_store		# no
	bra.b		iea_op_exc_ovfl		# yes
	
# an enabled exception occurred. we have to insert the exception type back into
# the machine.
iea_op_exc:
	subi.l		&24,%d0			# fix offset to be 0-8
	cmpi.b		%d0,&0x6		# is exception INEX?
	bne.b		iea_op_exc_force	# no

# the enabled exception was inexact. so, if it occurs with an overflow
# or underflow that was disabled, then we have to force an overflow or
# underflow frame.
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did overflow occur?
	bne.b		iea_op_exc_ovfl		# yes
	btst		&unfl_bit,FPSR_EXCEPT(%a6) # did underflow occur?
	bne.b		iea_op_exc_unfl		# yes

iea_op_exc_force:
	mov.w		(tbl_iea_except.b,%pc,%d0.w*2),2+FP_SRC(%a6)
	bra.b		iea_op_exit2		# exit with frestore

tbl_iea_except:
	short		0xe002, 0xe006, 0xe004, 0xe005
	short		0xe003, 0xe002, 0xe001, 0xe001

iea_op_exc_ovfl:
	mov.w		&0xe005,2+FP_SRC(%a6)
	bra.b		iea_op_exit2

iea_op_exc_unfl:
	mov.w		&0xe003,2+FP_SRC(%a6)

iea_op_exit2:
	mov.l		EXC_PC(%a6),USER_FPIAR(%a6) # set FPIAR to "Current PC"
	mov.l		EXC_EXTWPTR(%a6),EXC_PC(%a6) # set "Next PC" in exc frame

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore 	FP_SRC(%a6)		# restore exceptional state

	unlk		%a6			# unravel the frame

	btst		&0x7,(%sp)		# is trace on?
	bne.b		iea_op_trace		# yes

	bra.l		_fpsp_done		# exit to os
	
#
# The opclass two instruction that took an "Unimplemented Effective Address"
# exception was being traced. Make the "current" PC the FPIAR and put it in
# the trace stack frame then jump to _real_trace().
#					
#		 UNIMP EA FRAME		   TRACE FRAME
#		*****************	*****************
#		* 0x0 *  0x0f0	*	*    Current	*
#		*****************	*      PC	*
#		*    Current	*	*****************
#		*      PC	*	* 0x2 *  0x024	*
#		*****************	*****************
#		*      SR	*	*     Next	*
#		*****************	*      PC	*
#					*****************
#					*      SR	*
#					*****************
iea_op_trace:
	mov.l		(%sp),-(%sp)		# shift stack frame "down"
	mov.w		0x8(%sp),0x4(%sp)
	mov.w		&0x2024,0x6(%sp)	# stk fmt = 0x2; voff = 0x024
	fmov.l		%fpiar,0x8(%sp)		# "Current PC" is in FPIAR

	bra.l		_real_trace

#########################################################################
iea_fmovm:
	btst		&14,%d0			# ctrl or data reg
	beq.w		iea_fmovm_ctrl

iea_fmovm_data:

	btst		&0x5,EXC_SR(%a6)	# user or supervisor mode
	bne.b		iea_fmovm_data_s

iea_fmovm_data_u:
	mov.l		%usp,%a0
	mov.l		%a0,EXC_A7(%a6)		# store current a7	
	bsr.l		fmovm_dynamic		# do dynamic fmovm
	mov.l		EXC_A7(%a6),%a0		# load possibly new a7
	mov.l		%a0,%usp		# update usp
	bra.w		iea_fmovm_exit

iea_fmovm_data_s:
	clr.b		SPCOND_FLG(%a6)
	lea		0x2+EXC_VOFF(%a6),%a0
	mov.l		%a0,EXC_A7(%a6)
	bsr.l		fmovm_dynamic		# do dynamic fmovm

	cmpi.b		SPCOND_FLG(%a6),&mda7_flg
	beq.w		iea_fmovm_data_predec
	cmpi.b		SPCOND_FLG(%a6),&mia7_flg
	bne.w		iea_fmovm_exit

# right now, d0 = the size.
# the data has been fetched from the supervisor stack, but we have not
# incremented the stack pointer by the appropriate number of bytes.
# do it here.
iea_fmovm_data_postinc:
	btst		&0x7,EXC_SR(%a6)
	bne.b		iea_fmovm_data_pi_trace

	mov.w		EXC_SR(%a6),(EXC_SR,%a6,%d0)
	mov.l		EXC_EXTWPTR(%a6),(EXC_PC,%a6,%d0)
	mov.w		&0x00f0,(EXC_VOFF,%a6,%d0)

	lea		(EXC_SR,%a6,%d0),%a0
	mov.l		%a0,EXC_SR(%a6)
	
	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	unlk		%a6
	mov.l		(%sp)+,%sp
	bra.l		_fpsp_done

iea_fmovm_data_pi_trace:
	mov.w		EXC_SR(%a6),(EXC_SR-0x4,%a6,%d0)
	mov.l		EXC_EXTWPTR(%a6),(EXC_PC-0x4,%a6,%d0)
	mov.w		&0x2024,(EXC_VOFF-0x4,%a6,%d0)
	mov.l		EXC_PC(%a6),(EXC_VOFF+0x2-0x4,%a6,%d0)

	lea		(EXC_SR-0x4,%a6,%d0),%a0
	mov.l		%a0,EXC_SR(%a6)
	
	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	unlk		%a6
	mov.l		(%sp)+,%sp
	bra.l		_real_trace
	
# right now, d1 = size and d0 = the strg.
iea_fmovm_data_predec:
	mov.b		%d1,EXC_VOFF(%a6)	# store strg
	mov.b		%d0,0x1+EXC_VOFF(%a6)	# store size

	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	mov.l		(%a6),-(%sp)		# make a copy of a6
	mov.l		%d0,-(%sp)		# save d0
	mov.l		%d1,-(%sp)		# save d1
	mov.l		EXC_EXTWPTR(%a6),-(%sp)	# make a copy of Next PC

	clr.l		%d0
	mov.b		0x1+EXC_VOFF(%a6),%d0	# fetch size
	neg.l		%d0			# get negative of size

	btst		&0x7,EXC_SR(%a6)	# is trace enabled?
	beq.b		iea_fmovm_data_p2

	mov.w		EXC_SR(%a6),(EXC_SR-0x4,%a6,%d0)
	mov.l		EXC_PC(%a6),(EXC_VOFF-0x2,%a6,%d0)
	mov.l		(%sp)+,(EXC_PC-0x4,%a6,%d0)
	mov.w		&0x2024,(EXC_VOFF-0x4,%a6,%d0)

	pea		(%a6,%d0)		# create final sp
	bra.b		iea_fmovm_data_p3

iea_fmovm_data_p2:
	mov.w		EXC_SR(%a6),(EXC_SR,%a6,%d0)
	mov.l		(%sp)+,(EXC_PC,%a6,%d0)
	mov.w		&0x00f0,(EXC_VOFF,%a6,%d0)

	pea		(0x4,%a6,%d0)		# create final sp

iea_fmovm_data_p3:
	clr.l		%d1
	mov.b		EXC_VOFF(%a6),%d1	# fetch strg

	tst.b		%d1
	bpl.b		fm_1
	fmovm.x		&0x80,(0x4+0x8,%a6,%d0)
	addi.l		&0xc,%d0
fm_1:
	lsl.b		&0x1,%d1
	bpl.b		fm_2
	fmovm.x		&0x40,(0x4+0x8,%a6,%d0)
	addi.l		&0xc,%d0
fm_2:
	lsl.b		&0x1,%d1
	bpl.b		fm_3
	fmovm.x		&0x20,(0x4+0x8,%a6,%d0)
	addi.l		&0xc,%d0
fm_3:
	lsl.b		&0x1,%d1
	bpl.b		fm_4
	fmovm.x		&0x10,(0x4+0x8,%a6,%d0)
	addi.l		&0xc,%d0
fm_4:
	lsl.b		&0x1,%d1
	bpl.b		fm_5
	fmovm.x		&0x08,(0x4+0x8,%a6,%d0)
	addi.l		&0xc,%d0
fm_5:
	lsl.b		&0x1,%d1
	bpl.b		fm_6
	fmovm.x		&0x04,(0x4+0x8,%a6,%d0)
	addi.l		&0xc,%d0
fm_6:
	lsl.b		&0x1,%d1
	bpl.b		fm_7
	fmovm.x		&0x02,(0x4+0x8,%a6,%d0)
	addi.l		&0xc,%d0
fm_7:
	lsl.b		&0x1,%d1
	bpl.b		fm_end
	fmovm.x		&0x01,(0x4+0x8,%a6,%d0)
fm_end:
	mov.l		0x4(%sp),%d1
	mov.l		0x8(%sp),%d0
	mov.l		0xc(%sp),%a6
	mov.l		(%sp)+,%sp

	btst		&0x7,(%sp)		# is trace enabled?
	beq.l		_fpsp_done
	bra.l		_real_trace

#########################################################################
iea_fmovm_ctrl:

	bsr.l		fmovm_ctrl		# load ctrl regs

iea_fmovm_exit:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	btst		&0x7,EXC_SR(%a6)	# is trace on?
	bne.b		iea_fmovm_trace		# yes

	mov.l		EXC_EXTWPTR(%a6),EXC_PC(%a6) # set Next PC

	unlk		%a6			# unravel the frame

	bra.l		_fpsp_done		# exit to os

#
# The control reg instruction that took an "Unimplemented Effective Address"
# exception was being traced. The "Current PC" for the trace frame is the 
# PC stacked for Unimp EA. The "Next PC" is in EXC_EXTWPTR.
# After fixing the stack frame, jump to _real_trace().
#					
#		 UNIMP EA FRAME		   TRACE FRAME
#		*****************	*****************
#		* 0x0 *  0x0f0	*	*    Current	*
#		*****************	*      PC	*
#		*    Current	*	*****************
#		*      PC	*	* 0x2 *  0x024	*
#		*****************	*****************
#		*      SR	*	*     Next	*
#		*****************	*      PC	*
#					*****************
#					*      SR	*
#					*****************
# this ain't a pretty solution, but it works:
# -restore a6 (not with unlk)
# -shift stack frame down over where old a6 used to be
# -add LOCAL_SIZE to stack pointer
iea_fmovm_trace:
	mov.l		(%a6),%a6		# restore frame pointer
	mov.w		EXC_SR+LOCAL_SIZE(%sp),0x0+LOCAL_SIZE(%sp)
	mov.l		EXC_PC+LOCAL_SIZE(%sp),0x8+LOCAL_SIZE(%sp)
	mov.l		EXC_EXTWPTR+LOCAL_SIZE(%sp),0x2+LOCAL_SIZE(%sp)
	mov.w		&0x2024,0x6+LOCAL_SIZE(%sp) # stk fmt = 0x2; voff = 0x024
	add.l		&LOCAL_SIZE,%sp		# clear stack frame

	bra.l		_real_trace

#########################################################################
# The FPU is disabled and so we should really have taken the "Line
# F Emulator" exception. So, here we create an 8-word stack frame
# from our 4-word stack frame. This means we must calculate the length
# the faulting instruction to get the "next PC". This is trivial for
# immediate operands but requires some extra work for fmovm dynamic
# which can use most addressing modes.
iea_disabled:
	mov.l		(%sp)+,%d0		# restore d0

	link		%a6,&-LOCAL_SIZE	# init stack frame

	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1

# PC of instruction that took the exception is the PC in the frame
	mov.l		EXC_PC(%a6),EXC_EXTWPTR(%a6)
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)	# store OPWORD and EXTWORD

	tst.w		%d0			# is instr fmovm?
	bmi.b		iea_dis_fmovm		# yes
# instruction is using an extended precision immediate operand. therefore,
# the total instruction length is 16 bytes.
iea_dis_immed:
	mov.l		&0x10,%d0		# 16 bytes of instruction
	bra.b		iea_dis_cont
iea_dis_fmovm:
	btst		&0xe,%d0		# is instr fmovm ctrl
	bne.b		iea_dis_fmovm_data	# no
# the instruction is a fmovm.l with 2 or 3 registers.
	bfextu		%d0{&19:&3},%d1
	mov.l		&0xc,%d0
	cmpi.b		%d1,&0x7		# move all regs?
	bne.b		iea_dis_cont
	addq.l		&0x4,%d0
	bra.b		iea_dis_cont
# the instruction is an fmovm.x dynamic which can use many addressing
# modes and thus can have several different total instruction lengths.
# call fmovm_calc_ea which will go through the ea calc process and,
# as a by-product, will tell us how long the instruction is.
iea_dis_fmovm_data:
	clr.l		%d0
	bsr.l		fmovm_calc_ea
	mov.l		EXC_EXTWPTR(%a6),%d0
	sub.l		EXC_PC(%a6),%d0
iea_dis_cont:
	mov.w		%d0,EXC_VOFF(%a6)	# store stack shift value

	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

# here, we actually create the 8-word frame from the 4-word frame,
# with the "next PC" as additional info.
# the <ea> field is let as undefined.
	subq.l		&0x8,%sp		# make room for new stack
	mov.l		%d0,-(%sp)		# save d0
	mov.w		0xc(%sp),0x4(%sp)	# move SR
	mov.l		0xe(%sp),0x6(%sp)	# move Current PC
	clr.l		%d0
	mov.w		0x12(%sp),%d0
	mov.l		0x6(%sp),0x10(%sp)	# move Current PC
	add.l		%d0,0x6(%sp)		# make Next PC
	mov.w		&0x402c,0xa(%sp)	# insert offset,frame format
	mov.l		(%sp)+,%d0		# restore d0

	bra.l		_real_fpu_disabled

##########

iea_iacc:
	movc		%pcr,%d0
	btst		&0x1,%d0
	bne.b		iea_iacc_cont
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1 on stack
iea_iacc_cont:
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

	subq.w		&0x8,%sp		# make stack frame bigger
	mov.l		0x8(%sp),(%sp)		# store SR,hi(PC)
	mov.w		0xc(%sp),0x4(%sp)	# store lo(PC)
	mov.w		&0x4008,0x6(%sp)	# store voff
	mov.l		0x2(%sp),0x8(%sp)	# store ea
	mov.l		&0x09428001,0xc(%sp)	# store fslw

iea_acc_done:
	btst		&0x5,(%sp)		# user or supervisor mode?
	beq.b		iea_acc_done2		# user
	bset		&0x2,0xd(%sp)		# set supervisor TM bit

iea_acc_done2:
	bra.l		_real_access

iea_dacc:
	lea		-LOCAL_SIZE(%a6),%sp

	movc		%pcr,%d1
	btst		&0x1,%d1
	bne.b		iea_dacc_cont
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1 on stack
	fmovm.l		LOCAL_SIZE+USER_FPCR(%sp),%fpcr,%fpsr,%fpiar # restore ctrl regs
iea_dacc_cont:
	mov.l		(%a6),%a6

	mov.l		0x4+LOCAL_SIZE(%sp),-0x8+0x4+LOCAL_SIZE(%sp)
	mov.w		0x8+LOCAL_SIZE(%sp),-0x8+0x8+LOCAL_SIZE(%sp)
	mov.w		&0x4008,-0x8+0xa+LOCAL_SIZE(%sp)
	mov.l		%a0,-0x8+0xc+LOCAL_SIZE(%sp)
	mov.w		%d0,-0x8+0x10+LOCAL_SIZE(%sp)
	mov.w		&0x0001,-0x8+0x12+LOCAL_SIZE(%sp)

	movm.l		LOCAL_SIZE+EXC_DREGS(%sp),&0x0303 # restore d0-d1/a0-a1
	add.w		&LOCAL_SIZE-0x4,%sp

	bra.b		iea_acc_done

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_operr(): 060FPSP entry point for FP Operr exception.	#
#									#
#	This handler should be the first code executed upon taking the	#
# 	FP Operand Error exception in an operating system.		#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read instruction longword			#
#	fix_skewed_ops() - adjust src operand in fsave frame		#
#	_real_operr() - "callout" to operating system operr handler	#
#	_dmem_write_{byte,word,long}() - store data to mem (opclass 3)	#
#	store_dreg_{b,w,l}() - store data to data regfile (opclass 3)	#
#	facc_out_{b,w,l}() - store to memory took access error (opcl 3)	#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the FP Operr exception frame	#
#	- The fsave frame contains the source operand			#
# 									#
# OUTPUT **************************************************************	#
#	No access error:						#
#	- The system stack is unchanged					#
#	- The fsave frame contains the adjusted src op for opclass 0,2	#
#									#
# ALGORITHM ***********************************************************	#
#	In a system where the FP Operr exception is enabled, the goal	#
# is to get to the handler specified at _real_operr(). But, on the 060,	#
# for opclass zero and two instruction taking this exception, the 	#
# input operand in the fsave frame may be incorrect for some cases	#
# and needs to be corrected. This handler calls fix_skewed_ops() to	#
# do just this and then exits through _real_operr().			#
#	For opclass 3 instructions, the 060 doesn't store the default	#
# operr result out to memory or data register file as it should.	#
# This code must emulate the move out before finally exiting through	#
# _real_inex(). The move out, if to memory, is performed using 		#
# _mem_write() "callout" routines that may return a failing result.	#
# In this special case, the handler must exit through facc_out() 	#
# which creates an access error stack frame from the current operr	#
# stack frame.								#
#									#
#########################################################################

	global		_fpsp_operr
_fpsp_operr:

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	fsave		FP_SRC(%a6)		# grab the "busy" frame

 	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
 	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

# the FPIAR holds the "current PC" of the faulting instruction
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)
	
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)

##############################################################################

	btst		&13,%d0			# is instr an fmove out?
	bne.b		foperr_out		# fmove out


# here, we simply see if the operand in the fsave frame needs to be "unskewed".
# this would be the case for opclass two operations with a source infinity or
# denorm operand in the sgl or dbl format. NANs also become skewed, but can't 
# cause an operr so we don't need to check for them here.
	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		fix_skewed_ops		# fix src op

foperr_exit:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)

	unlk		%a6
	bra.l		_real_operr

########################################################################

#
# the hardware does not save the default result to memory on enabled
# operand error exceptions. we do this here before passing control to
# the user operand error handler.
#
# byte, word, and long destination format operations can pass
# through here. we simply need to test the sign of the src
# operand and save the appropriate minimum or maximum integer value
# to the effective address as pointed to by the stacked effective address.
#
# although packed opclass three operations can take operand error
# exceptions, they won't pass through here since they are caught
# first by the unsupported data format exception handler. that handler
# sends them directly to _real_operr() if necessary.
#
foperr_out:

	mov.w		FP_SRC_EX(%a6),%d1	# fetch exponent
	andi.w		&0x7fff,%d1
	cmpi.w		%d1,&0x7fff
	bne.b		foperr_out_not_qnan
# the operand is either an infinity or a QNAN.
	tst.l		FP_SRC_LO(%a6)
	bne.b		foperr_out_qnan
	mov.l		FP_SRC_HI(%a6),%d1
	andi.l		&0x7fffffff,%d1
	beq.b		foperr_out_not_qnan
foperr_out_qnan:
	mov.l		FP_SRC_HI(%a6),L_SCR1(%a6)
	bra.b		foperr_out_jmp

foperr_out_not_qnan:
	mov.l		&0x7fffffff,%d1
	tst.b		FP_SRC_EX(%a6)
	bpl.b		foperr_out_not_qnan2
	addq.l		&0x1,%d1
foperr_out_not_qnan2:
	mov.l		%d1,L_SCR1(%a6)

foperr_out_jmp:
	bfextu		%d0{&19:&3},%d0		# extract dst format field
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract <ea> mode,reg
	mov.w		(tbl_operr.b,%pc,%d0.w*2),%a0
	jmp		(tbl_operr.b,%pc,%a0)

tbl_operr:
	short		foperr_out_l - tbl_operr # long word integer
	short		tbl_operr    - tbl_operr # sgl prec shouldn't happen
	short		tbl_operr    - tbl_operr # ext prec shouldn't happen
	short		foperr_exit  - tbl_operr # packed won't enter here
	short		foperr_out_w - tbl_operr # word integer
	short		tbl_operr    - tbl_operr # dbl prec shouldn't happen
	short		foperr_out_b - tbl_operr # byte integer
	short		tbl_operr    - tbl_operr # packed won't enter here
	
foperr_out_b:
	mov.b		L_SCR1(%a6),%d0		# load positive default result
	cmpi.b		%d1,&0x7		# is <ea> mode a data reg?
	ble.b		foperr_out_b_save_dn	# yes
	mov.l		EXC_EA(%a6),%a0		# pass: <ea> of default result
	bsr.l		_dmem_write_byte	# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_b		# yes

	bra.w		foperr_exit
foperr_out_b_save_dn:
	andi.w		&0x0007,%d1
	bsr.l		store_dreg_b		# store result to regfile
	bra.w		foperr_exit

foperr_out_w:
	mov.w		L_SCR1(%a6),%d0		# load positive default result
	cmpi.b		%d1,&0x7		# is <ea> mode a data reg?
	ble.b		foperr_out_w_save_dn	# yes
	mov.l		EXC_EA(%a6),%a0		# pass: <ea> of default result
	bsr.l		_dmem_write_word	# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_w		# yes

	bra.w		foperr_exit
foperr_out_w_save_dn:
	andi.w		&0x0007,%d1
	bsr.l		store_dreg_w		# store result to regfile
	bra.w		foperr_exit

foperr_out_l:
	mov.l		L_SCR1(%a6),%d0		# load positive default result
	cmpi.b		%d1,&0x7		# is <ea> mode a data reg?
	ble.b		foperr_out_l_save_dn	# yes
	mov.l		EXC_EA(%a6),%a0		# pass: <ea> of default result
	bsr.l		_dmem_write_long	# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_l		# yes

	bra.w		foperr_exit
foperr_out_l_save_dn:
	andi.w		&0x0007,%d1
	bsr.l		store_dreg_l		# store result to regfile
	bra.w		foperr_exit

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_snan(): 060FPSP entry point for FP SNAN exception.	#
#									#
#	This handler should be the first code executed upon taking the	#
# 	FP Signalling NAN exception in an operating system.		#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read instruction longword			#
#	fix_skewed_ops() - adjust src operand in fsave frame		#
#	_real_snan() - "callout" to operating system SNAN handler	#
#	_dmem_write_{byte,word,long}() - store data to mem (opclass 3)	#
#	store_dreg_{b,w,l}() - store data to data regfile (opclass 3)	#
#	facc_out_{b,w,l,d,x}() - store to mem took acc error (opcl 3)	#
#	_calc_ea_fout() - fix An if <ea> is -() or ()+; also get <ea>	#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the FP SNAN exception frame		#
#	- The fsave frame contains the source operand			#
# 									#
# OUTPUT **************************************************************	#
#	No access error:						#
#	- The system stack is unchanged					#
#	- The fsave frame contains the adjusted src op for opclass 0,2	#
#									#
# ALGORITHM ***********************************************************	#
#	In a system where the FP SNAN exception is enabled, the goal	#
# is to get to the handler specified at _real_snan(). But, on the 060,	#
# for opclass zero and two instructions taking this exception, the 	#
# input operand in the fsave frame may be incorrect for some cases	#
# and needs to be corrected. This handler calls fix_skewed_ops() to	#
# do just this and then exits through _real_snan().			#
#	For opclass 3 instructions, the 060 doesn't store the default	#
# SNAN result out to memory or data register file as it should.		#
# This code must emulate the move out before finally exiting through	#
# _real_snan(). The move out, if to memory, is performed using 		#
# _mem_write() "callout" routines that may return a failing result.	#
# In this special case, the handler must exit through facc_out() 	#
# which creates an access error stack frame from the current SNAN	#
# stack frame.								#
#	For the case of an extended precision opclass 3 instruction,	#
# if the effective addressing mode was -() or ()+, then the address	#
# register must get updated by calling _calc_ea_fout(). If the <ea>	#
# was -(a7) from supervisor mode, then the exception frame currently	#
# on the system stack must be carefully moved "down" to make room	#
# for the operand being moved.						#
#									#
#########################################################################

	global		_fpsp_snan
_fpsp_snan:

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	fsave		FP_SRC(%a6)		# grab the "busy" frame

 	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
 	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

# the FPIAR holds the "current PC" of the faulting instruction
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)
	
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)

##############################################################################

	btst		&13,%d0			# is instr an fmove out?
	bne.w		fsnan_out		# fmove out


# here, we simply see if the operand in the fsave frame needs to be "unskewed".
# this would be the case for opclass two operations with a source infinity or
# denorm operand in the sgl or dbl format. NANs also become skewed and must be
# fixed here.
	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		fix_skewed_ops		# fix src op

fsnan_exit:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)

	unlk		%a6
	bra.l		_real_snan
		
########################################################################

#
# the hardware does not save the default result to memory on enabled
# snan exceptions. we do this here before passing control to
# the user snan handler.
#
# byte, word, long, and packed destination format operations can pass
# through here. since packed format operations already were handled by
# fpsp_unsupp(), then we need to do nothing else for them here. 
# for byte, word, and long, we simply need to test the sign of the src
# operand and save the appropriate minimum or maximum integer value
# to the effective address as pointed to by the stacked effective address.
#
fsnan_out:

	bfextu		%d0{&19:&3},%d0		# extract dst format field
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract <ea> mode,reg
	mov.w		(tbl_snan.b,%pc,%d0.w*2),%a0
	jmp		(tbl_snan.b,%pc,%a0)

tbl_snan:
	short		fsnan_out_l - tbl_snan # long word integer
	short		fsnan_out_s - tbl_snan # sgl prec shouldn't happen
	short		fsnan_out_x - tbl_snan # ext prec shouldn't happen
	short		tbl_snan    - tbl_snan # packed needs no help
	short		fsnan_out_w - tbl_snan # word integer
	short		fsnan_out_d - tbl_snan # dbl prec shouldn't happen
	short		fsnan_out_b - tbl_snan # byte integer
	short		tbl_snan    - tbl_snan # packed needs no help
	
fsnan_out_b:
	mov.b		FP_SRC_HI(%a6),%d0	# load upper byte of SNAN
	bset		&6,%d0			# set SNAN bit
	cmpi.b		%d1,&0x7		# is <ea> mode a data reg?
	ble.b		fsnan_out_b_dn		# yes
	mov.l		EXC_EA(%a6),%a0		# pass: <ea> of default result
	bsr.l		_dmem_write_byte	# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_b		# yes

	bra.w		fsnan_exit
fsnan_out_b_dn:
	andi.w		&0x0007,%d1
	bsr.l		store_dreg_b		# store result to regfile
	bra.w		fsnan_exit

fsnan_out_w:
	mov.w		FP_SRC_HI(%a6),%d0	# load upper word of SNAN
	bset		&14,%d0			# set SNAN bit
	cmpi.b		%d1,&0x7		# is <ea> mode a data reg?
	ble.b		fsnan_out_w_dn		# yes
	mov.l		EXC_EA(%a6),%a0		# pass: <ea> of default result
	bsr.l		_dmem_write_word	# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_w		# yes

	bra.w		fsnan_exit
fsnan_out_w_dn:
	andi.w		&0x0007,%d1
	bsr.l		store_dreg_w		# store result to regfile
	bra.w		fsnan_exit

fsnan_out_l:
	mov.l		FP_SRC_HI(%a6),%d0	# load upper longword of SNAN
	bset		&30,%d0			# set SNAN bit
	cmpi.b		%d1,&0x7		# is <ea> mode a data reg?
	ble.b		fsnan_out_l_dn		# yes
	mov.l		EXC_EA(%a6),%a0		# pass: <ea> of default result
	bsr.l		_dmem_write_long	# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_l		# yes

	bra.w		fsnan_exit
fsnan_out_l_dn:
	andi.w		&0x0007,%d1
	bsr.l		store_dreg_l		# store result to regfile
	bra.w		fsnan_exit

fsnan_out_s:
	cmpi.b		%d1,&0x7		# is <ea> mode a data reg?
	ble.b		fsnan_out_d_dn		# yes
	mov.l		FP_SRC_EX(%a6),%d0	# fetch SNAN sign
	andi.l		&0x80000000,%d0		# keep sign
	ori.l		&0x7fc00000,%d0		# insert new exponent,SNAN bit
	mov.l		FP_SRC_HI(%a6),%d1	# load mantissa
	lsr.l		&0x8,%d1		# shift mantissa for sgl
	or.l		%d1,%d0			# create sgl SNAN
	mov.l		EXC_EA(%a6),%a0		# pass: <ea> of default result
	bsr.l		_dmem_write_long	# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_l		# yes

	bra.w		fsnan_exit
fsnan_out_d_dn:
	mov.l		FP_SRC_EX(%a6),%d0	# fetch SNAN sign
	andi.l		&0x80000000,%d0		# keep sign
	ori.l		&0x7fc00000,%d0		# insert new exponent,SNAN bit
	mov.l		%d1,-(%sp)
	mov.l		FP_SRC_HI(%a6),%d1	# load mantissa
	lsr.l		&0x8,%d1		# shift mantissa for sgl
	or.l		%d1,%d0			# create sgl SNAN
	mov.l		(%sp)+,%d1
	andi.w		&0x0007,%d1
	bsr.l		store_dreg_l		# store result to regfile
	bra.w		fsnan_exit

fsnan_out_d:
	mov.l		FP_SRC_EX(%a6),%d0	# fetch SNAN sign
	andi.l		&0x80000000,%d0		# keep sign
	ori.l		&0x7ff80000,%d0		# insert new exponent,SNAN bit
	mov.l		FP_SRC_HI(%a6),%d1	# load hi mantissa
	mov.l		%d0,FP_SCR0_EX(%a6)	# store to temp space
	mov.l		&11,%d0			# load shift amt
	lsr.l		%d0,%d1
	or.l		%d1,FP_SCR0_EX(%a6)	# create dbl hi
	mov.l		FP_SRC_HI(%a6),%d1	# load hi mantissa
	andi.l		&0x000007ff,%d1
	ror.l		%d0,%d1
	mov.l		%d1,FP_SCR0_HI(%a6)	# store to temp space
	mov.l		FP_SRC_LO(%a6),%d1	# load lo mantissa
	lsr.l		%d0,%d1
	or.l		%d1,FP_SCR0_HI(%a6)	# create dbl lo
	lea		FP_SCR0(%a6),%a0	# pass: ptr to operand
	mov.l		EXC_EA(%a6),%a1		# pass: dst addr
	movq.l		&0x8,%d0		# pass: size of 8 bytes
	bsr.l		_dmem_write		# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_d		# yes

	bra.w		fsnan_exit

# for extended precision, if the addressing mode is pre-decrement or
# post-increment, then the address register did not get updated.
# in addition, for pre-decrement, the stacked <ea> is incorrect.
fsnan_out_x:
	clr.b		SPCOND_FLG(%a6)		# clear special case flag

	mov.w		FP_SRC_EX(%a6),FP_SCR0_EX(%a6)
	clr.w		2+FP_SCR0(%a6)
	mov.l		FP_SRC_HI(%a6),%d0
	bset		&30,%d0
	mov.l		%d0,FP_SCR0_HI(%a6)
	mov.l		FP_SRC_LO(%a6),FP_SCR0_LO(%a6)

	btst		&0x5,EXC_SR(%a6)	# supervisor mode exception?
	bne.b		fsnan_out_x_s		# yes

	mov.l		%usp,%a0		# fetch user stack pointer
	mov.l		%a0,EXC_A7(%a6)		# save on stack for calc_ea()
	mov.l		(%a6),EXC_A6(%a6)
	
	bsr.l		_calc_ea_fout		# find the correct ea,update An
	mov.l		%a0,%a1
	mov.l		%a0,EXC_EA(%a6)		# stack correct <ea>

	mov.l		EXC_A7(%a6),%a0
	mov.l		%a0,%usp		# restore user stack pointer
	mov.l		EXC_A6(%a6),(%a6)

fsnan_out_x_save:
	lea		FP_SCR0(%a6),%a0	# pass: ptr to operand
	movq.l		&0xc,%d0		# pass: size of extended
	bsr.l		_dmem_write		# write the default result

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_x		# yes

	bra.w		fsnan_exit

fsnan_out_x_s:
	mov.l		(%a6),EXC_A6(%a6)

	bsr.l		_calc_ea_fout		# find the correct ea,update An
	mov.l		%a0,%a1
	mov.l		%a0,EXC_EA(%a6)		# stack correct <ea>

	mov.l		EXC_A6(%a6),(%a6)

	cmpi.b		SPCOND_FLG(%a6),&mda7_flg # is <ea> mode -(a7)?
	bne.b		fsnan_out_x_save	# no

# the operation was "fmove.x SNAN,-(a7)" from supervisor mode.
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)

	mov.l		EXC_A6(%a6),%a6		# restore frame pointer

	mov.l		LOCAL_SIZE+EXC_SR(%sp),LOCAL_SIZE+EXC_SR-0xc(%sp)
	mov.l		LOCAL_SIZE+EXC_PC+0x2(%sp),LOCAL_SIZE+EXC_PC+0x2-0xc(%sp)
	mov.l		LOCAL_SIZE+EXC_EA(%sp),LOCAL_SIZE+EXC_EA-0xc(%sp)

	mov.l		LOCAL_SIZE+FP_SCR0_EX(%sp),LOCAL_SIZE+EXC_SR(%sp)
	mov.l		LOCAL_SIZE+FP_SCR0_HI(%sp),LOCAL_SIZE+EXC_PC+0x2(%sp)
	mov.l		LOCAL_SIZE+FP_SCR0_LO(%sp),LOCAL_SIZE+EXC_EA(%sp)

	add.l		&LOCAL_SIZE-0x8,%sp
	
	bra.l		_real_snan

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_inex(): 060FPSP entry point for FP Inexact exception.	#
#									#
#	This handler should be the first code executed upon taking the	#
# 	FP Inexact exception in an operating system.			#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read instruction longword			#
#	fix_skewed_ops() - adjust src operand in fsave frame		#
#	set_tag_x() - determine optype of src/dst operands		#
#	store_fpreg() - store opclass 0 or 2 result to FP regfile	#
#	unnorm_fix() - change UNNORM operands to NORM or ZERO		#
#	load_fpn2() - load dst operand from FP regfile			#
#	smovcr() - emulate an "fmovcr" instruction			#
#	fout() - emulate an opclass 3 instruction			#
#	tbl_unsupp - add of table of emulation routines for opclass 0,2	#
#	_real_inex() - "callout" to operating system inexact handler	#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the FP Inexact exception frame	#
#	- The fsave frame contains the source operand			#
# 									#
# OUTPUT **************************************************************	#
#	- The system stack is unchanged					#
#	- The fsave frame contains the adjusted src op for opclass 0,2	#
#									#
# ALGORITHM ***********************************************************	#
#	In a system where the FP Inexact exception is enabled, the goal	#
# is to get to the handler specified at _real_inex(). But, on the 060,	#
# for opclass zero and two instruction taking this exception, the 	#
# hardware doesn't store the correct result to the destination FP	#
# register as did the '040 and '881/2. This handler must emulate the 	#
# instruction in order to get this value and then store it to the 	#
# correct register before calling _real_inex().				#
#	For opclass 3 instructions, the 060 doesn't store the default	#
# inexact result out to memory or data register file as it should.	#
# This code must emulate the move out by calling fout() before finally	#
# exiting through _real_inex().						#
#									#
#########################################################################

	global		_fpsp_inex
_fpsp_inex:

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	fsave		FP_SRC(%a6)		# grab the "busy" frame

 	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
 	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

# the FPIAR holds the "current PC" of the faulting instruction
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)
	
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)

##############################################################################

	btst		&13,%d0			# is instr an fmove out?
	bne.w		finex_out		# fmove out


# the hardware, for "fabs" and "fneg" w/ a long source format, puts the 
# longword integer directly into the upper longword of the mantissa along
# w/ an exponent value of 0x401e. we convert this to extended precision here.
	bfextu		%d0{&19:&3},%d0		# fetch instr size
	bne.b		finex_cont		# instr size is not long
	cmpi.w		FP_SRC_EX(%a6),&0x401e	# is exponent 0x401e?
	bne.b		finex_cont		# no
	fmov.l		&0x0,%fpcr
	fmov.l		FP_SRC_HI(%a6),%fp0	# load integer src
	fmov.x		%fp0,FP_SRC(%a6)	# store integer as extended precision
	mov.w		&0xe001,0x2+FP_SRC(%a6)

finex_cont:
	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		fix_skewed_ops		# fix src op

# Here, we zero the ccode and exception byte field since we're going to
# emulate the whole instruction. Notice, though, that we don't kill the
# INEX1 bit. This is because a packed op has long since been converted
# to extended before arriving here. Therefore, we need to retain the
# INEX1 bit from when the operand was first converted.
	andi.l		&0x00ff01ff,USER_FPSR(%a6) # zero all but accured field

	fmov.l		&0x0,%fpcr		# zero current control regs
	fmov.l		&0x0,%fpsr

	bfextu		EXC_EXTWORD(%a6){&0:&6},%d1 # extract upper 6 of cmdreg
	cmpi.b		%d1,&0x17		# is op an fmovecr?
	beq.w		finex_fmovcr		# yes

	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		set_tag_x		# tag the operand type
	mov.b		%d0,STAG(%a6)		# maybe NORM,DENORM

# bits four and five of the fp extension word separate the monadic and dyadic
# operations that can pass through fpsp_inex(). remember that fcmp and ftst
# will never take this exception, but fsincos will.
	btst		&0x5,1+EXC_CMDREG(%a6)	# is operation monadic or dyadic?
	beq.b		finex_extract		# monadic

	btst		&0x4,1+EXC_CMDREG(%a6)	# is operation an fsincos?
	bne.b		finex_extract		# yes

	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # dyadic; load dst reg
	bsr.l		load_fpn2		# load dst into FP_DST

	lea		FP_DST(%a6),%a0		# pass: ptr to dst op
	bsr.l		set_tag_x		# tag the operand type
	cmpi.b		%d0,&UNNORM		# is operand an UNNORM?
	bne.b		finex_op2_done		# no
	bsr.l		unnorm_fix		# yes; convert to NORM,DENORM,or ZERO
finex_op2_done:
	mov.b		%d0,DTAG(%a6)		# save dst optype tag

finex_extract:
	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass rnd prec/mode

	mov.b		1+EXC_CMDREG(%a6),%d1
	andi.w		&0x007f,%d1		# extract extension

	lea		FP_SRC(%a6),%a0
	lea		FP_DST(%a6),%a1

	mov.l		(tbl_unsupp.l,%pc,%d1.w*4),%d1 # fetch routine addr
	jsr		(tbl_unsupp.l,%pc,%d1.l*1)

# the operation has been emulated. the result is in fp0.
finex_save:
	bfextu		EXC_CMDREG(%a6){&6:&3},%d0
	bsr.l		store_fpreg

finex_exit:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)

	unlk		%a6
	bra.l		_real_inex

finex_fmovcr:
	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass rnd prec,mode
	mov.b		1+EXC_CMDREG(%a6),%d1
	andi.l		&0x0000007f,%d1		# pass rom offset
	bsr.l		smovcr
	bra.b		finex_save

########################################################################

#
# the hardware does not save the default result to memory on enabled
# inexact exceptions. we do this here before passing control to
# the user inexact handler.
#
# byte, word, and long destination format operations can pass
# through here. so can double and single precision.
# although packed opclass three operations can take inexact
# exceptions, they won't pass through here since they are caught
# first by the unsupported data format exception handler. that handler
# sends them directly to _real_inex() if necessary.
#
finex_out:

	mov.b		&NORM,STAG(%a6)		# src is a NORM

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# pass rnd prec,mode

	andi.l		&0xffff00ff,USER_FPSR(%a6) # zero exception field

	lea		FP_SRC(%a6),%a0		# pass ptr to src operand

	bsr.l		fout			# store the default result

	bra.b		finex_exit

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_dz(): 060FPSP entry point for FP DZ exception.		#
#									#
#	This handler should be the first code executed upon taking	#
#	the FP DZ exception in an operating system.			#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read instruction longword from memory	#
#	fix_skewed_ops() - adjust fsave operand				#
#	_real_dz() - "callout" exit point from FP DZ handler		#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the FP DZ exception stack.		#
#	- The fsave frame contains the source operand.			#
# 									#
# OUTPUT **************************************************************	#
#	- The system stack contains the FP DZ exception stack.		#
#	- The fsave frame contains the adjusted source operand.		#
#									#
# ALGORITHM ***********************************************************	#
#	In a system where the DZ exception is enabled, the goal is to	#
# get to the handler specified at _real_dz(). But, on the 060, when the	#
# exception is taken, the input operand in the fsave state frame may	#
# be incorrect for some cases and need to be adjusted. So, this package	#
# adjusts the operand using fix_skewed_ops() and then branches to	#
# _real_dz(). 								#
#									#
#########################################################################

	global		_fpsp_dz
_fpsp_dz:

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	fsave		FP_SRC(%a6)		# grab the "busy" frame

 	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
 	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1 on stack

# the FPIAR holds the "current PC" of the faulting instruction
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)
	
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)

##############################################################################


# here, we simply see if the operand in the fsave frame needs to be "unskewed".
# this would be the case for opclass two operations with a source zero
# in the sgl or dbl format.
	lea		FP_SRC(%a6),%a0		# pass: ptr to src op
	bsr.l		fix_skewed_ops		# fix src op

fdz_exit:
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)

	unlk		%a6
	bra.l		_real_dz

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_fline(): 060FPSP entry point for "Line F emulator" exc.	#
#									#
#	This handler should be the first code executed upon taking the	#
#	"Line F Emulator" exception in an operating system.		#
#									#
# XREF ****************************************************************	#
#	_fpsp_unimp() - handle "FP Unimplemented" exceptions		#
#	_real_fpu_disabled() - handle "FPU disabled" exceptions		#
#	_real_fline() - handle "FLINE" exceptions			#
#	_imem_read_long() - read instruction longword			#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains a "Line F Emulator" exception	#
#	  stack frame.							#
# 									#
# OUTPUT **************************************************************	#
#	- The system stack is unchanged					#
#									#
# ALGORITHM ***********************************************************	#
#	When a "Line F Emulator" exception occurs, there are 3 possible	#
# exception types, denoted by the exception stack frame format number:	#
#	(1) FPU unimplemented instruction (6 word stack frame)		#
#	(2) FPU disabled (8 word stack frame)				#
#	(3) Line F (4 word stack frame)					#
#									#
#	This module determines which and forks the flow off to the 	#
# appropriate "callout" (for "disabled" and "Line F") or to the		#
# correct emulation code (for "FPU unimplemented").			#
#	This code also must check for "fmovecr" instructions w/ a	#
# non-zero <ea> field. These may get flagged as "Line F" but should	#
# really be flagged as "FPU Unimplemented". (This is a "feature" on	#
# the '060.								#
#									#
#########################################################################

	global		_fpsp_fline
_fpsp_fline:

# check to see if this exception is a "FP Unimplemented Instruction"
# exception. if so, branch directly to that handler's entry point.
	cmpi.w		0x6(%sp),&0x202c
	beq.l		_fpsp_unimp

# check to see if the FPU is disabled. if so, jump to the OS entry
# point for that condition.
	cmpi.w		0x6(%sp),&0x402c
	beq.l		_real_fpu_disabled

# the exception was an "F-Line Illegal" exception. we check to see
# if the F-Line instruction is an "fmovecr" w/ a non-zero <ea>. if
# so, convert the F-Line exception stack frame to an FP Unimplemented
# Instruction exception stack frame else branch to the OS entry
# point for the F-Line exception handler.
	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1

	mov.l		EXC_PC(%a6),EXC_EXTWPTR(%a6)
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch instruction words

	bfextu		%d0{&0:&10},%d1		# is it an fmovecr?
	cmpi.w		%d1,&0x03c8
	bne.b		fline_fline		# no

	bfextu		%d0{&16:&6},%d1		# is it an fmovecr?
	cmpi.b		%d1,&0x17
	bne.b		fline_fline		# no

# it's an fmovecr w/ a non-zero <ea> that has entered through
# the F-Line Illegal exception.
# so, we need to convert the F-Line exception stack frame into an
# FP Unimplemented Instruction stack frame and jump to that entry
# point.
#
# but, if the FPU is disabled, then we need to jump to the FPU diabled
# entry point.
	movc		%pcr,%d0
	btst		&0x1,%d0
	beq.b		fline_fmovcr

	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

	sub.l		&0x8,%sp		# make room for "Next PC", <ea>
	mov.w		0x8(%sp),(%sp)
	mov.l		0xa(%sp),0x2(%sp)	# move "Current PC"
	mov.w		&0x402c,0x6(%sp)
	mov.l		0x2(%sp),0xc(%sp)
	addq.l		&0x4,0x2(%sp)		# set "Next PC"

	bra.l		_real_fpu_disabled

fline_fmovcr:
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

	fmov.l		0x2(%sp),%fpiar		# set current PC
	addq.l		&0x4,0x2(%sp)		# set Next PC

	mov.l		(%sp),-(%sp)
	mov.l		0x8(%sp),0x4(%sp)
	mov.b		&0x20,0x6(%sp)

	bra.l		_fpsp_unimp

fline_fline:
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

	bra.l		_real_fline

#########################################################################
# XDEF ****************************************************************	#
#	_fpsp_unimp(): 060FPSP entry point for FP "Unimplemented	#
#		       Instruction" exception.				#
#									#
#	This handler should be the first code executed upon taking the	#
#	FP Unimplemented Instruction exception in an operating system.	#
#									#
# XREF ****************************************************************	#
#	_imem_read_{word,long}() - read instruction word/longword	#
#	load_fop() - load src/dst ops from memory and/or FP regfile	#
#	store_fpreg() - store opclass 0 or 2 result to FP regfile	#
#	tbl_trans - addr of table of emulation routines for trnscndls	#
#	_real_access() - "callout" for access error exception		#
#	_fpsp_done() - "callout" for exit; work all done		#
#	_real_trace() - "callout" for Trace enabled exception		#
#	smovcr() - emulate "fmovecr" instruction			#
#	funimp_skew() - adjust fsave src ops to "incorrect" value	#
#	_ftrapcc() - emulate an "ftrapcc" instruction			#
#	_fdbcc() - emulate an "fdbcc" instruction			#
#	_fscc() - emulate an "fscc" instruction				#
#	_real_trap() - "callout" for Trap exception			#
# 	_real_bsun() - "callout" for enabled Bsun exception		#
#									#
# INPUT ***************************************************************	#
#	- The system stack contains the "Unimplemented Instr" stk frame	#
# 									#
# OUTPUT **************************************************************	#
#	If access error:						#
#	- The system stack is changed to an access error stack frame	#
#	If Trace exception enabled:					#
#	- The system stack is changed to a Trace exception stack frame	#
#	Else: (normal case)						#
#	- Correct result has been stored as appropriate			#
#									#
# ALGORITHM ***********************************************************	#
#	There are two main cases of instructions that may enter here to	#
# be emulated: (1) the FPgen instructions, most of which were also	#
# unimplemented on the 040, and (2) "ftrapcc", "fscc", and "fdbcc".	#
#	For the first set, this handler calls the routine load_fop()	#
# to load the source and destination (for dyadic) operands to be used	#
# for instruction emulation. The correct emulation routine is then 	#
# chosen by decoding the instruction type and indexing into an 		#
# emulation subroutine index table. After emulation returns, this 	#
# handler checks to see if an exception should occur as a result of the #
# FP instruction emulation. If so, then an FP exception of the correct	#
# type is inserted into the FPU state frame using the "frestore"	#
# instruction before exiting through _fpsp_done(). In either the 	#
# exceptional or non-exceptional cases, we must check to see if the	#
# Trace exception is enabled. If so, then we must create a Trace	#
# exception frame from the current exception frame and exit through	#
# _real_trace().							#
# 	For "fdbcc", "ftrapcc", and "fscc", the emulation subroutines	#
# _fdbcc(), _ftrapcc(), and _fscc() respectively are used. All three	#
# may flag that a BSUN exception should be taken. If so, then the 	#
# current exception stack frame is converted into a BSUN exception 	#
# stack frame and an exit is made through _real_bsun(). If the		#
# instruction was "ftrapcc" and a Trap exception should result, a Trap	#
# exception stack frame is created from the current frame and an exit	#
# is made through _real_trap(). If a Trace exception is pending, then	#
# a Trace exception frame is created from the current frame and a jump	#
# is made to _real_trace(). Finally, if none of these conditions exist,	#
# then the handler exits though the callout _fpsp_done().		#
#									#
# 	In any of the above scenarios, if a _mem_read() or _mem_write()	#
# "callout" returns a failing value, then an access error stack frame	#
# is created from the current stack frame and an exit is made through	#
# _real_access().							#
#									#
#########################################################################

#
# FP UNIMPLEMENTED INSTRUCTION STACK FRAME:
#
#	*****************
#	*		* => <ea> of fp unimp instr.
#	-      EA	-
#	*		*
#	*****************
#	* 0x2 *  0x02c	* => frame format and vector offset(vector #11)
#	*****************
#	*		*
#	-    Next PC	- => PC of instr to execute after exc handling
#	*		*
#	*****************
#	*      SR	* => SR at the time the exception was taken
#	*****************
#
# Note: the !NULL bit does not get set in the fsave frame when the
# machine encounters an fp unimp exception. Therefore, it must be set
# before leaving this handler.
#
	global		_fpsp_unimp
_fpsp_unimp:

	link.w		%a6,&-LOCAL_SIZE	# init stack frame

	movm.l		&0x0303,EXC_DREGS(%a6)	# save d0-d1/a0-a1
	fmovm.l		%fpcr,%fpsr,%fpiar,USER_FPCR(%a6) # save ctrl regs
	fmovm.x		&0xc0,EXC_FPREGS(%a6)	# save fp0-fp1

	btst		&0x5,EXC_SR(%a6)	# user mode exception?
	bne.b		funimp_s		# no; supervisor mode

# save the value of the user stack pointer onto the stack frame
funimp_u:
	mov.l		%usp,%a0		# fetch user stack pointer
	mov.l		%a0,EXC_A7(%a6)		# store in stack frame
	bra.b		funimp_cont

# store the value of the supervisor stack pointer BEFORE the exc occurred.
# old_sp is address just above stacked effective address.
funimp_s:
	lea		4+EXC_EA(%a6),%a0	# load old a7'
	mov.l		%a0,EXC_A7(%a6)		# store a7'
	mov.l		%a0,OLD_A7(%a6)		# make a copy

funimp_cont:

# the FPIAR holds the "current PC" of the faulting instruction.
	mov.l		USER_FPIAR(%a6),EXC_EXTWPTR(%a6)

	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch the instruction words
	mov.l		%d0,EXC_OPWORD(%a6)

############################################################################

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	clr.b		SPCOND_FLG(%a6)		# clear "special case" flag

# Divide the fp instructions into 8 types based on the TYPE field in
# bits 6-8 of the opword(classes 6,7 are undefined).
# (for the '060, only two types  can take this exception)
#	bftst		%d0{&7:&3}		# test TYPE
	btst		&22,%d0			# type 0 or 1 ?
	bne.w		funimp_misc		# type 1

#########################################
# TYPE == 0: General instructions	#
#########################################
funimp_gen:

	clr.b		STORE_FLG(%a6)		# clear "store result" flag

# clear the ccode byte and exception status byte
	andi.l		&0x00ff00ff,USER_FPSR(%a6)

	bfextu		%d0{&16:&6},%d1		# extract upper 6 of cmdreg
	cmpi.b		%d1,&0x17		# is op an fmovecr?
	beq.w		funimp_fmovcr		# yes

funimp_gen_op:
	bsr.l		_load_fop		# load 

	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0	# fetch rnd mode

	mov.b		1+EXC_CMDREG(%a6),%d1
	andi.w		&0x003f,%d1		# extract extension bits
	lsl.w		&0x3,%d1		# shift right 3 bits
	or.b		STAG(%a6),%d1		# insert src optag bits

	lea		FP_DST(%a6),%a1		# pass dst ptr in a1
	lea		FP_SRC(%a6),%a0		# pass src ptr in a0

	mov.w		(tbl_trans.w,%pc,%d1.w*2),%d1
	jsr		(tbl_trans.w,%pc,%d1.w*1) # emulate

funimp_fsave:
	mov.b		FPCR_ENABLE(%a6),%d0	# fetch exceptions enabled
	bne.w		funimp_ena		# some are enabled

funimp_store:
	bfextu		EXC_CMDREG(%a6){&6:&3},%d0 # fetch Dn
	bsr.l		store_fpreg		# store result to fp regfile

funimp_gen_exit:
	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

funimp_gen_exit_cmp:
	cmpi.b		SPCOND_FLG(%a6),&mia7_flg # was the ea mode (sp)+ ?
	beq.b		funimp_gen_exit_a7	# yes

	cmpi.b		SPCOND_FLG(%a6),&mda7_flg # was the ea mode -(sp) ?
	beq.b		funimp_gen_exit_a7	# yes

funimp_gen_exit_cont:
	unlk		%a6

funimp_gen_exit_cont2:
	btst		&0x7,(%sp)		# is trace on?
	beq.l		_fpsp_done		# no

# this catches a problem with the case where an exception will be re-inserted
# into the machine. the frestore has already been executed...so, the fmov.l
# alone of the control register would trigger an unwanted exception.
# until I feel like fixing this, we'll sidestep the exception.
	fsave		-(%sp)
	fmov.l		%fpiar,0x14(%sp)	# "Current PC" is in FPIAR
	frestore	(%sp)+
	mov.w		&0x2024,0x6(%sp)	# stk fmt = 0x2; voff = 0x24
	bra.l		_real_trace
	
funimp_gen_exit_a7:
	btst		&0x5,EXC_SR(%a6)	# supervisor or user mode?
	bne.b		funimp_gen_exit_a7_s	# supervisor

	mov.l		%a0,-(%sp)
	mov.l		EXC_A7(%a6),%a0
	mov.l		%a0,%usp
	mov.l		(%sp)+,%a0
	bra.b		funimp_gen_exit_cont

# if the instruction was executed from supervisor mode and the addressing
# mode was (a7)+, then the stack frame for the rte must be shifted "up"
# "n" bytes where "n" is the size of the src operand type.
# f<op>.{b,w,l,s,d,x,p}
funimp_gen_exit_a7_s:
	mov.l		%d0,-(%sp)		# save d0
	mov.l		EXC_A7(%a6),%d0		# load new a7'
	sub.l		OLD_A7(%a6),%d0		# subtract old a7'
	mov.l		0x2+EXC_PC(%a6),(0x2+EXC_PC,%a6,%d0) # shift stack frame
	mov.l		EXC_SR(%a6),(EXC_SR,%a6,%d0) # shift stack frame
	mov.w		%d0,EXC_SR(%a6)		# store incr number
	mov.l		(%sp)+,%d0		# restore d0

	unlk		%a6

	add.w		(%sp),%sp		# stack frame shifted
	bra.b		funimp_gen_exit_cont2		

######################
# fmovecr.x #ccc,fpn #
######################
funimp_fmovcr:
	clr.l		%d0
	mov.b		FPCR_MODE(%a6),%d0
	mov.b		1+EXC_CMDREG(%a6),%d1
	andi.l		&0x0000007f,%d1		# pass rom offset in d1
	bsr.l		smovcr
	bra.w		funimp_fsave

#########################################################################

#
# the user has enabled some exceptions. we figure not to see this too
# often so that's why it gets lower priority.
#
funimp_ena:

# was an exception set that was also enabled?
	and.b		FPSR_EXCEPT(%a6),%d0	# keep only ones enabled and set
	bfffo		%d0{&24:&8},%d0		# find highest priority exception
	bne.b		funimp_exc		# at least one was set

# no exception that was enabled was set BUT if we got an exact overflow
# and overflow wasn't enabled but inexact was (yech!) then this is
# an inexact exception; otherwise, return to normal non-exception flow.
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did overflow occur?
	beq.w		funimp_store		# no; return to normal flow

# the overflow w/ exact result happened but was inexact set in the FPCR?
funimp_ovfl:
	btst		&inex2_bit,FPCR_ENABLE(%a6) # is inexact enabled?
	beq.w		funimp_store		# no; return to normal flow
	bra.b		funimp_exc_ovfl		# yes

# some exception happened that was actually enabled.
# we'll insert this new exception into the FPU and then return.
funimp_exc:
	subi.l		&24,%d0			# fix offset to be 0-8
	cmpi.b		%d0,&0x6		# is exception INEX?
	bne.b		funimp_exc_force	# no

# the enabled exception was inexact. so, if it occurs with an overflow
# or underflow that was disabled, then we have to force an overflow or
# underflow frame. the eventual overflow or underflow handler will see that
# it's actually an inexact and act appropriately. this is the only easy
# way to have the EXOP available for the enabled inexact handler when
# a disabled overflow or underflow has also happened.
	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did overflow occur?
	bne.b		funimp_exc_ovfl		# yes
	btst		&unfl_bit,FPSR_EXCEPT(%a6) # did underflow occur?
	bne.b		funimp_exc_unfl		# yes

# force the fsave exception status bits to signal an exception of the 
# appropriate type. don't forget to "skew" the source operand in case we
# "unskewed" the one the hardware initially gave us.
funimp_exc_force:
	mov.l		%d0,-(%sp)		# save d0
	bsr.l		funimp_skew		# check for special case
	mov.l		(%sp)+,%d0		# restore d0
	mov.w		(tbl_funimp_except.b,%pc,%d0.w*2),2+FP_SRC(%a6)
	bra.b		funimp_gen_exit2	# exit with frestore

tbl_funimp_except:
	short		0xe002, 0xe006, 0xe004, 0xe005
	short		0xe003, 0xe002, 0xe001, 0xe001

# insert an overflow frame
funimp_exc_ovfl:
	bsr.l		funimp_skew		# check for special case
	mov.w		&0xe005,2+FP_SRC(%a6)
	bra.b		funimp_gen_exit2

# insert an underflow frame
funimp_exc_unfl:
	bsr.l		funimp_skew		# check for special case
	mov.w		&0xe003,2+FP_SRC(%a6)

# this is the general exit point for an enabled exception that will be
# restored into the machine for the instruction just emulated.
funimp_gen_exit2:
	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# insert exceptional status

	bra.w		funimp_gen_exit_cmp

############################################################################

#
# TYPE == 1: FDB<cc>, FS<cc>, FTRAP<cc>
#
# These instructions were implemented on the '881/2 and '040 in hardware but
# are emulated in software on the '060.
#
funimp_misc:
	bfextu		%d0{&10:&3},%d1		# extract mode field
	cmpi.b		%d1,&0x1		# is it an fdb<cc>?
	beq.w		funimp_fdbcc		# yes
	cmpi.b		%d1,&0x7		# is it an fs<cc>?
	bne.w		funimp_fscc		# yes
	bfextu		%d0{&13:&3},%d1	
	cmpi.b		%d1,&0x2		# is it an fs<cc>?
	blt.w		funimp_fscc		# yes

#########################
# ftrap<cc>		#
# ftrap<cc>.w #<data>	#
# ftrap<cc>.l #<data>	#
#########################
funimp_ftrapcc:

	bsr.l		_ftrapcc		# FTRAP<cc>()

	cmpi.b		SPCOND_FLG(%a6),&fbsun_flg # is enabled bsun occurring?
	beq.w		funimp_bsun		# yes

	cmpi.b		SPCOND_FLG(%a6),&ftrapcc_flg # should a trap occur?
	bne.w		funimp_done		# no

#	 FP UNIMP FRAME		   TRAP  FRAME
#	*****************	*****************
#	**    <EA>     **	**  Current PC **
#	*****************	*****************
#	* 0x2 *  0x02c	*	* 0x2 *  0x01c  *
#	*****************	*****************
#	**   Next PC   **	**   Next PC   **
#	*****************	*****************
#	*      SR	*	*      SR	*
#	*****************	*****************
#	    (6 words)		    (6 words)
#
# the ftrapcc instruction should take a trap. so, here we must create a
# trap stack frame from an unimplemented fp instruction stack frame and
# jump to the user supplied entry point for the trap exception
funimp_ftrapcc_tp:
	mov.l		USER_FPIAR(%a6),EXC_EA(%a6) # Address = Current PC
	mov.w		&0x201c,EXC_VOFF(%a6)	# Vector Offset = 0x01c

	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	unlk		%a6
	bra.l		_real_trap

#########################
# fdb<cc> Dn,<label>	#
#########################
funimp_fdbcc:

	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word		# read displacement

	tst.l		%d1			# did ifetch fail?
	bne.w		funimp_iacc		# yes

	ext.l		%d0			# sign extend displacement

	bsr.l		_fdbcc			# FDB<cc>()

	cmpi.b		SPCOND_FLG(%a6),&fbsun_flg # is enabled bsun occurring?
	beq.w		funimp_bsun

	bra.w		funimp_done		# branch to finish

#################
# fs<cc>.b <ea>	#
#################
funimp_fscc:

	bsr.l		_fscc			# FS<cc>()

# I am assuming here that an "fs<cc>.b -(An)" or "fs<cc>.b (An)+" instruction
# does not need to update "An" before taking a bsun exception.
	cmpi.b		SPCOND_FLG(%a6),&fbsun_flg # is enabled bsun occurring?
	beq.w		funimp_bsun

	btst		&0x5,EXC_SR(%a6)	# yes; is it a user mode exception?
	bne.b		funimp_fscc_s		# no

funimp_fscc_u:
	mov.l		EXC_A7(%a6),%a0		# yes; set new USP
	mov.l		%a0,%usp
	bra.w		funimp_done		# branch to finish	

# remember, I'm assuming that post-increment is bogus...(it IS!!!)
# so, the least significant WORD of the stacked effective address got
# overwritten by the "fs<cc> -(An)". We must shift the stack frame "down"
# so that the rte will work correctly without destroying the result.
# even though the operation size is byte, the stack ptr is decr by 2.
#
# remember, also, this instruction may be traced.
funimp_fscc_s:
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg # was a7 modified?
	bne.w		funimp_done		# no

	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	unlk		%a6

	btst		&0x7,(%sp)		# is trace enabled?
	bne.b		funimp_fscc_s_trace	# yes

	subq.l		&0x2,%sp
	mov.l		0x2(%sp),(%sp)		# shift SR,hi(PC) "down"
	mov.l		0x6(%sp),0x4(%sp)	# shift lo(PC),voff "down"
	bra.l		_fpsp_done

funimp_fscc_s_trace:
	subq.l		&0x2,%sp
	mov.l		0x2(%sp),(%sp)		# shift SR,hi(PC) "down"
	mov.w		0x6(%sp),0x4(%sp)	# shift lo(PC)
	mov.w		&0x2024,0x6(%sp)	# fmt/voff = $2024
	fmov.l		%fpiar,0x8(%sp)		# insert "current PC"

	bra.l		_real_trace
		
#
# The ftrap<cc>, fs<cc>, or fdb<cc> is to take an enabled bsun. we must convert
# the fp unimplemented instruction exception stack frame into a bsun stack frame,
# restore a bsun exception into the machine, and branch to the user
# supplied bsun hook.
#
#	 FP UNIMP FRAME		   BSUN FRAME
#	*****************	*****************
#	**    <EA>     **	* 0x0 * 0x0c0	*
#	*****************	*****************
#	* 0x2 *  0x02c  *	** Current PC  **
#	*****************	*****************
#	**   Next PC   **	*      SR	*
#	*****************	*****************
#	*      SR	*	    (4 words)
#	*****************
#	    (6 words)
#
funimp_bsun:
	mov.w		&0x00c0,2+EXC_EA(%a6)	# Fmt = 0x0; Vector Offset = 0x0c0
	mov.l		USER_FPIAR(%a6),EXC_VOFF(%a6) # PC = Current PC
	mov.w		EXC_SR(%a6),2+EXC_PC(%a6) # shift SR "up"

	mov.w		&0xe000,2+FP_SRC(%a6)	# bsun exception enabled

	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	frestore	FP_SRC(%a6)		# restore bsun exception

	unlk		%a6

	addq.l		&0x4,%sp		# erase sludge

	bra.l		_real_bsun		# branch to user bsun hook

#
# all ftrapcc/fscc/fdbcc processing has been completed. unwind the stack frame
# and return.
#
# as usual, we have to check for trace mode being on here. since instructions
# modifying the supervisor stack frame don't pass through here, this is a 
# relatively easy task.
#
funimp_done:
	fmovm.x		EXC_FP0(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
 	movm.l		EXC_DREGS(%a6),&0x0303 	# restore d0-d1/a0-a1

	unlk		%a6

	btst		&0x7,(%sp)		# is trace enabled?
	bne.b		funimp_trace		# yes

	bra.l		_fpsp_done

#	 FP UNIMP FRAME		  TRACE  FRAME
#	*****************	*****************
#	**    <EA>     **	**  Current PC **
#	*****************	*****************
#	* 0x2 *  0x02c	*	* 0x2 *  0x024  *
#	*****************	*****************
#	**   Next PC   **	**   Next PC   **
#	*****************	*****************
#	*      SR	*	*      SR	*
#	*****************	*****************
#	    (6 words)		    (6 words)
#
# the fscc instruction should take a trace trap. so, here we must create a
# trace stack frame from an unimplemented fp instruction stack frame and
# jump to the user supplied entry point for the trace exception
funimp_trace:
	fmov.l		%fpiar,0x8(%sp)		# current PC is in fpiar
	mov.b		&0x24,0x7(%sp)		# vector offset = 0x024

	bra.l		_real_trace

################################################################

	global		tbl_trans
	swbeg		&0x1c0
tbl_trans:
	short 		tbl_trans - tbl_trans	# $00-0 fmovecr all
	short 		tbl_trans - tbl_trans	# $00-1 fmovecr all
	short 		tbl_trans - tbl_trans	# $00-2 fmovecr all
	short 		tbl_trans - tbl_trans	# $00-3 fmovecr all
	short 		tbl_trans - tbl_trans	# $00-4 fmovecr all
	short 		tbl_trans - tbl_trans	# $00-5 fmovecr all
	short 		tbl_trans - tbl_trans	# $00-6 fmovecr all
	short 		tbl_trans - tbl_trans	# $00-7 fmovecr all

	short 		tbl_trans - tbl_trans	# $01-0 fint norm
	short		tbl_trans - tbl_trans	# $01-1 fint zero
	short		tbl_trans - tbl_trans	# $01-2 fint inf
	short		tbl_trans - tbl_trans	# $01-3 fint qnan
	short		tbl_trans - tbl_trans	# $01-5 fint denorm
	short		tbl_trans - tbl_trans	# $01-4 fint snan
	short		tbl_trans - tbl_trans	# $01-6 fint unnorm
	short		tbl_trans - tbl_trans	# $01-7 ERROR

	short		ssinh	 - tbl_trans	# $02-0 fsinh norm
	short		src_zero - tbl_trans	# $02-1 fsinh zero
	short		src_inf	 - tbl_trans	# $02-2 fsinh inf
	short		src_qnan - tbl_trans	# $02-3 fsinh qnan
	short		ssinhd	 - tbl_trans	# $02-5 fsinh denorm
	short		src_snan - tbl_trans	# $02-4 fsinh snan
	short		tbl_trans - tbl_trans	# $02-6 fsinh unnorm
	short		tbl_trans - tbl_trans	# $02-7 ERROR

	short		tbl_trans - tbl_trans	# $03-0 fintrz norm
	short		tbl_trans - tbl_trans	# $03-1 fintrz zero
	short		tbl_trans - tbl_trans	# $03-2 fintrz inf
	short		tbl_trans - tbl_trans	# $03-3 fintrz qnan
	short		tbl_trans - tbl_trans	# $03-5 fintrz denorm
	short		tbl_trans - tbl_trans	# $03-4 fintrz snan
	short		tbl_trans - tbl_trans	# $03-6 fintrz unnorm
	short		tbl_trans - tbl_trans	# $03-7 ERROR

	short		tbl_trans - tbl_trans	# $04-0 fsqrt norm
	short		tbl_trans - tbl_trans	# $04-1 fsqrt zero
	short		tbl_trans - tbl_trans	# $04-2 fsqrt inf
	short		tbl_trans - tbl_trans	# $04-3 fsqrt qnan
	short		tbl_trans - tbl_trans	# $04-5 fsqrt denorm
	short		tbl_trans - tbl_trans	# $04-4 fsqrt snan
	short		tbl_trans - tbl_trans	# $04-6 fsqrt unnorm
	short		tbl_trans - tbl_trans	# $04-7 ERROR

	short		tbl_trans - tbl_trans	# $05-0 ERROR
	short		tbl_trans - tbl_trans	# $05-1 ERROR
	short		tbl_trans - tbl_trans	# $05-2 ERROR
	short		tbl_trans - tbl_trans	# $05-3 ERROR
	short		tbl_trans - tbl_trans	# $05-4 ERROR
	short		tbl_trans - tbl_trans	# $05-5 ERROR
	short		tbl_trans - tbl_trans	# $05-6 ERROR
	short		tbl_trans - tbl_trans	# $05-7 ERROR

	short		slognp1	 - tbl_trans	# $06-0 flognp1 norm
	short		src_zero - tbl_trans	# $06-1 flognp1 zero
	short		sopr_inf - tbl_trans	# $06-2 flognp1 inf
	short		src_qnan - tbl_trans	# $06-3 flognp1 qnan
	short		slognp1d - tbl_trans	# $06-5 flognp1 denorm
	short		src_snan - tbl_trans	# $06-4 flognp1 snan
	short		tbl_trans - tbl_trans	# $06-6 flognp1 unnorm
	short		tbl_trans - tbl_trans	# $06-7 ERROR

	short		tbl_trans - tbl_trans	# $07-0 ERROR
	short		tbl_trans - tbl_trans	# $07-1 ERROR
	short		tbl_trans - tbl_trans	# $07-2 ERROR
	short		tbl_trans - tbl_trans	# $07-3 ERROR
	short		tbl_trans - tbl_trans	# $07-4 ERROR
	short		tbl_trans - tbl_trans	# $07-5 ERROR
	short		tbl_trans - tbl_trans	# $07-6 ERROR
	short		tbl_trans - tbl_trans	# $07-7 ERROR

	short		setoxm1	 - tbl_trans	# $08-0 fetoxm1 norm
	short		src_zero - tbl_trans	# $08-1 fetoxm1 zero
	short		setoxm1i - tbl_trans	# $08-2 fetoxm1 inf
	short		src_qnan - tbl_trans	# $08-3 fetoxm1 qnan
	short		setoxm1d - tbl_trans	# $08-5 fetoxm1 denorm
	short		src_snan - tbl_trans	# $08-4 fetoxm1 snan
	short		tbl_trans - tbl_trans	# $08-6 fetoxm1 unnorm
	short		tbl_trans - tbl_trans	# $08-7 ERROR

	short		stanh	 - tbl_trans	# $09-0 ftanh norm
	short		src_zero - tbl_trans	# $09-1 ftanh zero
	short		src_one	 - tbl_trans	# $09-2 ftanh inf
	short		src_qnan - tbl_trans	# $09-3 ftanh qnan
	short		stanhd	 - tbl_trans	# $09-5 ftanh denorm
	short		src_snan - tbl_trans	# $09-4 ftanh snan
	short		tbl_trans - tbl_trans	# $09-6 ftanh unnorm
	short		tbl_trans - tbl_trans	# $09-7 ERROR

	short		satan	 - tbl_trans	# $0a-0 fatan norm
	short		src_zero - tbl_trans	# $0a-1 fatan zero
	short		spi_2	 - tbl_trans	# $0a-2 fatan inf
	short		src_qnan - tbl_trans	# $0a-3 fatan qnan
	short		satand	 - tbl_trans	# $0a-5 fatan denorm
	short		src_snan - tbl_trans	# $0a-4 fatan snan
	short		tbl_trans - tbl_trans	# $0a-6 fatan unnorm
	short		tbl_trans - tbl_trans	# $0a-7 ERROR

	short		tbl_trans - tbl_trans	# $0b-0 ERROR
	short		tbl_trans - tbl_trans	# $0b-1 ERROR
	short		tbl_trans - tbl_trans	# $0b-2 ERROR
	short		tbl_trans - tbl_trans	# $0b-3 ERROR
	short		tbl_trans - tbl_trans	# $0b-4 ERROR
	short		tbl_trans - tbl_trans	# $0b-5 ERROR
	short		tbl_trans - tbl_trans	# $0b-6 ERROR
	short		tbl_trans - tbl_trans	# $0b-7 ERROR

	short		sasin	 - tbl_trans	# $0c-0 fasin norm
	short		src_zero - tbl_trans	# $0c-1 fasin zero
	short		t_operr	 - tbl_trans	# $0c-2 fasin inf
	short		src_qnan - tbl_trans	# $0c-3 fasin qnan
	short		sasind	 - tbl_trans	# $0c-5 fasin denorm
	short		src_snan - tbl_trans	# $0c-4 fasin snan
	short		tbl_trans - tbl_trans	# $0c-6 fasin unnorm
	short		tbl_trans - tbl_trans	# $0c-7 ERROR

	short		satanh	 - tbl_trans	# $0d-0 fatanh norm
	short		src_zero - tbl_trans	# $0d-1 fatanh zero
	short		t_operr	 - tbl_trans	# $0d-2 fatanh inf
	short		src_qnan - tbl_trans	# $0d-3 fatanh qnan
	short		satanhd	 - tbl_trans	# $0d-5 fatanh denorm
	short		src_snan - tbl_trans	# $0d-4 fatanh snan
	short		tbl_trans - tbl_trans	# $0d-6 fatanh unnorm
	short		tbl_trans - tbl_trans	# $0d-7 ERROR

	short		ssin	 - tbl_trans	# $0e-0 fsin norm
	short		src_zero - tbl_trans	# $0e-1 fsin zero
	short		t_operr	 - tbl_trans	# $0e-2 fsin inf
	short		src_qnan - tbl_trans	# $0e-3 fsin qnan
	short		ssind	 - tbl_trans	# $0e-5 fsin denorm
	short		src_snan - tbl_trans	# $0e-4 fsin snan
	short		tbl_trans - tbl_trans	# $0e-6 fsin unnorm
	short		tbl_trans - tbl_trans	# $0e-7 ERROR
	
	short		stan	 - tbl_trans	# $0f-0 ftan norm
	short		src_zero - tbl_trans	# $0f-1 ftan zero
	short		t_operr	 - tbl_trans	# $0f-2 ftan inf
	short		src_qnan - tbl_trans	# $0f-3 ftan qnan
	short		stand	 - tbl_trans	# $0f-5 ftan denorm
	short		src_snan - tbl_trans	# $0f-4 ftan snan
	short		tbl_trans - tbl_trans	# $0f-6 ftan unnorm
	short		tbl_trans - tbl_trans	# $0f-7 ERROR

	short		setox	 - tbl_trans	# $10-0 fetox norm
	short		ld_pone	 - tbl_trans	# $10-1 fetox zero
	short		szr_inf	 - tbl_trans	# $10-2 fetox inf
	short		src_qnan - tbl_trans	# $10-3 fetox qnan
	short		setoxd	 - tbl_trans	# $10-5 fetox denorm
	short		src_snan - tbl_trans	# $10-4 fetox snan
	short		tbl_trans - tbl_trans	# $10-6 fetox unnorm
	short		tbl_trans - tbl_trans	# $10-7 ERROR

	short		stwotox	 - tbl_trans	# $11-0 ftwotox norm
	short		ld_pone	 - tbl_trans	# $11-1 ftwotox zero
	short		szr_inf	 - tbl_trans	# $11-2 ftwotox inf
	short		src_qnan - tbl_trans	# $11-3 ftwotox qnan
	short		stwotoxd - tbl_trans	# $11-5 ftwotox denorm
	short		src_snan - tbl_trans	# $11-4 ftwotox snan
	short		tbl_trans - tbl_trans	# $11-6 ftwotox unnorm
	short		tbl_trans - tbl_trans	# $11-7 ERROR

	short		stentox	 - tbl_trans	# $12-0 ftentox norm
	short		ld_pone	 - tbl_trans	# $12-1 ftentox zero
	short		szr_inf	 - tbl_trans	# $12-2 ftentox inf
	short		src_qnan - tbl_trans	# $12-3 ftentox qnan
	short		stentoxd - tbl_trans	# $12-5 ftentox denorm
	short		src_snan - tbl_trans	# $12-4 ftentox snan
	short		tbl_trans - tbl_trans	# $12-6 ftentox unnorm
	short		tbl_trans - tbl_trans	# $12-7 ERROR

	short		tbl_trans - tbl_trans	# $13-0 ERROR
	short		tbl_trans - tbl_trans	# $13-1 ERROR
	short		tbl_trans - tbl_trans	# $13-2 ERROR
	short		tbl_trans - tbl_trans	# $13-3 ERROR
	short		tbl_trans - tbl_trans	# $13-4 ERROR
	short		tbl_trans - tbl_trans	# $13-5 ERROR
	short		tbl_trans - tbl_trans	# $13-6 ERROR
	short		tbl_trans - tbl_trans	# $13-7 ERROR

	short		slogn	 - tbl_trans	# $14-0 flogn norm
	short		t_dz2	 - tbl_trans	# $14-1 flogn zero
	short		sopr_inf - tbl_trans	# $14-2 flogn inf
	short		src_qnan - tbl_trans	# $14-3 flogn qnan
	short		slognd	 - tbl_trans	# $14-5 flogn denorm
	short		src_snan - tbl_trans	# $14-4 flogn snan
	short		tbl_trans - tbl_trans	# $14-6 flogn unnorm
	short		tbl_trans - tbl_trans	# $14-7 ERROR

	short		slog10	 - tbl_trans	# $15-0 flog10 norm
	short		t_dz2	 - tbl_trans	# $15-1 flog10 zero
	short		sopr_inf - tbl_trans	# $15-2 flog10 inf
	short		src_qnan - tbl_trans	# $15-3 flog10 qnan
	short		slog10d	 - tbl_trans	# $15-5 flog10 denorm
	short		src_snan - tbl_trans	# $15-4 flog10 snan
	short		tbl_trans - tbl_trans	# $15-6 flog10 unnorm
	short		tbl_trans - tbl_trans	# $15-7 ERROR

	short		slog2	 - tbl_trans	# $16-0 flog2 norm
	short		t_dz2	 - tbl_trans	# $16-1 flog2 zero
	short		sopr_inf - tbl_trans	# $16-2 flog2 inf
	short		src_qnan - tbl_trans	# $16-3 flog2 qnan
	short		slog2d	 - tbl_trans	# $16-5 flog2 denorm
	short		src_snan - tbl_trans	# $16-4 flog2 snan
	short		tbl_trans - tbl_trans	# $16-6 flog2 unnorm
	short		tbl_trans - tbl_trans	# $16-7 ERROR

	short		tbl_trans - tbl_trans	# $17-0 ERROR
	short		tbl_trans - tbl_trans	# $17-1 ERROR
	short		tbl_trans - tbl_trans	# $17-2 ERROR
	short		tbl_trans - tbl_trans	# $17-3 ERROR
	short		tbl_trans - tbl_trans	# $17-4 ERROR
	short		tbl_trans - tbl_trans	# $17-5 ERROR
	short		tbl_trans - tbl_trans	# $17-6 ERROR
	short		tbl_trans - tbl_trans	# $17-7 ERROR

	short		tbl_trans - tbl_trans	# $18-0 fabs norm
	short		tbl_trans - tbl_trans	# $18-1 fabs zero
	short		tbl_trans - tbl_trans	# $18-2 fabs inf
	short		tbl_trans - tbl_trans	# $18-3 fabs qnan
	short		tbl_trans - tbl_trans	# $18-5 fabs denorm
	short		tbl_trans - tbl_trans	# $18-4 fabs snan
	short		tbl_trans - tbl_trans	# $18-6 fabs unnorm
	short		tbl_trans - tbl_trans	# $18-7 ERROR

	short		scosh	 - tbl_trans	# $19-0 fcosh norm
	short		ld_pone	 - tbl_trans	# $19-1 fcosh zero
	short		ld_pinf	 - tbl_trans	# $19-2 fcosh inf
	short		src_qnan - tbl_trans	# $19-3 fcosh qnan
	short		scoshd	 - tbl_trans	# $19-5 fcosh denorm
	short		src_snan - tbl_trans	# $19-4 fcosh snan
	short		tbl_trans - tbl_trans	# $19-6 fcosh unnorm
	short		tbl_trans - tbl_trans	# $19-7 ERROR

	short		tbl_trans - tbl_trans	# $1a-0 fneg norm
	short		tbl_trans - tbl_trans	# $1a-1 fneg zero
	short		tbl_trans - tbl_trans	# $1a-2 fneg inf
	short		tbl_trans - tbl_trans	# $1a-3 fneg qnan
	short		tbl_trans - tbl_trans	# $1a-5 fneg denorm
	short		tbl_trans - tbl_trans	# $1a-4 fneg snan
	short		tbl_trans - tbl_trans	# $1a-6 fneg unnorm
	short		tbl_trans - tbl_trans	# $1a-7 ERROR

	short		tbl_trans - tbl_trans	# $1b-0 ERROR
	short		tbl_trans - tbl_trans	# $1b-1 ERROR
	short		tbl_trans - tbl_trans	# $1b-2 ERROR
	short		tbl_trans - tbl_trans	# $1b-3 ERROR
	short		tbl_trans - tbl_trans	# $1b-4 ERROR
	short		tbl_trans - tbl_trans	# $1b-5 ERROR
	short		tbl_trans - tbl_trans	# $1b-6 ERROR
	short		tbl_trans - tbl_trans	# $1b-7 ERROR

	short		sacos	 - tbl_trans	# $1c-0 facos norm
	short		ld_ppi2	 - tbl_trans	# $1c-1 facos zero
	short		t_operr	 - tbl_trans	# $1c-2 facos inf
	short		src_qnan - tbl_trans	# $1c-3 facos qnan
	short		sacosd	 - tbl_trans	# $1c-5 facos denorm
	short		src_snan - tbl_trans	# $1c-4 facos snan
	short		tbl_trans - tbl_trans	# $1c-6 facos unnorm
	short		tbl_trans - tbl_trans	# $1c-7 ERROR

	short		scos	 - tbl_trans	# $1d-0 fcos norm
	short		ld_pone	 - tbl_trans	# $1d-1 fcos zero
	short		t_operr	 - tbl_trans	# $1d-2 fcos inf
	short		src_qnan - tbl_trans	# $1d-3 fcos qnan
	short		scosd	 - tbl_trans	# $1d-5 fcos denorm
	short		src_snan - tbl_trans	# $1d-4 fcos snan
	short		tbl_trans - tbl_trans	# $1d-6 fcos unnorm
	short		tbl_trans - tbl_trans	# $1d-7 ERROR

	short		sgetexp	 - tbl_trans	# $1e-0 fgetexp norm
	short		src_zero - tbl_trans	# $1e-1 fgetexp zero
	short		t_operr	 - tbl_trans	# $1e-2 fgetexp inf
	short		src_qnan - tbl_trans	# $1e-3 fgetexp qnan
	short		sgetexpd - tbl_trans	# $1e-5 fgetexp denorm
	short		src_snan - tbl_trans	# $1e-4 fgetexp snan
	short		tbl_trans - tbl_trans	# $1e-6 fgetexp unnorm
	short		tbl_trans - tbl_trans	# $1e-7 ERROR

	short		sgetman	 - tbl_trans	# $1f-0 fgetman norm
	short		src_zero - tbl_trans	# $1f-1 fgetman zero
	short		t_operr	 - tbl_trans	# $1f-2 fgetman inf
	short		src_qnan - tbl_trans	# $1f-3 fgetman qnan
	short		sgetmand - tbl_trans	# $1f-5 fgetman denorm
	short		src_snan - tbl_trans	# $1f-4 fgetman snan
	short		tbl_trans - tbl_trans	# $1f-6 fgetman unnorm
	short		tbl_trans - tbl_trans	# $1f-7 ERROR

	short		tbl_trans - tbl_trans	# $20-0 fdiv norm
	short		tbl_trans - tbl_trans	# $20-1 fdiv zero
	short		tbl_trans - tbl_trans	# $20-2 fdiv inf
	short		tbl_trans - tbl_trans	# $20-3 fdiv qnan
	short		tbl_trans - tbl_trans	# $20-5 fdiv denorm
	short		tbl_trans - tbl_trans	# $20-4 fdiv snan
	short		tbl_trans - tbl_trans	# $20-6 fdiv unnorm
	short		tbl_trans - tbl_trans	# $20-7 ERROR

	short		smod_snorm - tbl_trans	# $21-0 fmod norm
	short		smod_szero - tbl_trans	# $21-1 fmod zero
	short		smod_sinf - tbl_trans	# $21-2 fmod inf
	short		sop_sqnan - tbl_trans	# $21-3 fmod qnan
	short		smod_sdnrm - tbl_trans	# $21-5 fmod denorm
	short		sop_ssnan - tbl_trans	# $21-4 fmod snan
	short		tbl_trans - tbl_trans	# $21-6 fmod unnorm
	short		tbl_trans - tbl_trans	# $21-7 ERROR

	short		tbl_trans - tbl_trans	# $22-0 fadd norm
	short		tbl_trans - tbl_trans	# $22-1 fadd zero
	short		tbl_trans - tbl_trans	# $22-2 fadd inf
	short		tbl_trans - tbl_trans	# $22-3 fadd qnan
	short		tbl_trans - tbl_trans	# $22-5 fadd denorm
	short		tbl_trans - tbl_trans	# $22-4 fadd snan
	short		tbl_trans - tbl_trans	# $22-6 fadd unnorm
	short		tbl_trans - tbl_trans	# $22-7 ERROR

	short		tbl_trans - tbl_trans	# $23-0 fmul norm
	short		tbl_trans - tbl_trans	# $23-1 fmul zero
	short		tbl_trans - tbl_trans	# $23-2 fmul inf
	short		tbl_trans - tbl_trans	# $23-3 fmul qnan
	short		tbl_trans - tbl_trans	# $23-5 fmul denorm
	short		tbl_trans - tbl_trans	# $23-4 fmul snan
	short		tbl_trans - tbl_trans	# $23-6 fmul unnorm
	short		tbl_trans - tbl_trans	# $23-7 ERROR

	short		tbl_trans - tbl_trans	# $24-0 fsgldiv norm
	short		tbl_trans - tbl_trans	# $24-1 fsgldiv zero
	short		tbl_trans - tbl_trans	# $24-2 fsgldiv inf
	short		tbl_trans - tbl_trans	# $24-3 fsgldiv qnan
	short		tbl_trans - tbl_trans	# $24-5 fsgldiv denorm
	short		tbl_trans - tbl_trans	# $24-4 fsgldiv snan
	short		tbl_trans - tbl_trans	# $24-6 fsgldiv unnorm
	short		tbl_trans - tbl_trans	# $24-7 ERROR

	short		srem_snorm - tbl_trans	# $25-0 frem norm
	short		srem_szero - tbl_trans	# $25-1 frem zero
	short		srem_sinf - tbl_trans	# $25-2 frem inf
	short		sop_sqnan - tbl_trans	# $25-3 frem qnan
	short		srem_sdnrm - tbl_trans	# $25-5 frem denorm
	short		sop_ssnan - tbl_trans	# $25-4 frem snan
	short		tbl_trans - tbl_trans	# $25-6 frem unnorm
	short		tbl_trans - tbl_trans	# $25-7 ERROR

	short		sscale_snorm - tbl_trans # $26-0 fscale norm
	short		sscale_szero - tbl_trans # $26-1 fscale zero
	short		sscale_sinf - tbl_trans	# $26-2 fscale inf
	short		sop_sqnan - tbl_trans	# $26-3 fscale qnan
	short		sscale_sdnrm - tbl_trans # $26-5 fscale denorm
	short		sop_ssnan - tbl_trans	# $26-4 fscale snan
	short		tbl_trans - tbl_trans	# $26-6 fscale unnorm
	short		tbl_trans - tbl_trans	# $26-7 ERROR

	short		tbl_trans - tbl_trans	# $27-0 fsglmul norm
	short		tbl_trans - tbl_trans	# $27-1 fsglmul zero
	short		tbl_trans - tbl_trans	# $27-2 fsglmul inf
	short		tbl_trans - tbl_trans	# $27-3 fsglmul qnan
	short		tbl_trans - tbl_trans	# $27-5 fsglmul denorm
	short		tbl_trans - tbl_trans	# $27-4 fsglmul snan
	short		tbl_trans - tbl_trans	# $27-6 fsglmul unnorm
	short		tbl_trans - tbl_trans	# $27-7 ERROR

	short		tbl_trans - tbl_trans	# $28-0 fsub norm
	short		tbl_trans - tbl_trans	# $28-1 fsub zero
	short		tbl_trans - tbl_trans	# $28-2 fsub inf
	short		tbl_trans - tbl_trans	# $28-3 fsub qnan
	short		tbl_trans - tbl_trans	# $28-5 fsub denorm
	short		tbl_trans - tbl_trans	# $28-4 fsub snan
	short		tbl_trans - tbl_trans	# $28-6 fsub unnorm
	short		tbl_trans - tbl_trans	# $28-7 ERROR

	short		tbl_trans - tbl_trans	# $29-0 ERROR
	short		tbl_trans - tbl_trans	# $29-1 ERROR
	short		tbl_trans - tbl_trans	# $29-2 ERROR
	short		tbl_trans - tbl_trans	# $29-3 ERROR
	short		tbl_trans - tbl_trans	# $29-4 ERROR
	short		tbl_trans - tbl_trans	# $29-5 ERROR
	short		tbl_trans - tbl_trans	# $29-6 ERROR
	short		tbl_trans - tbl_trans	# $29-7 ERROR

	short		tbl_trans - tbl_trans	# $2a-0 ERROR
	short		tbl_trans - tbl_trans	# $2a-1 ERROR
	short		tbl_trans - tbl_trans	# $2a-2 ERROR
	short		tbl_trans - tbl_trans	# $2a-3 ERROR
	short		tbl_trans - tbl_trans	# $2a-4 ERROR
	short		tbl_trans - tbl_trans	# $2a-5 ERROR
	short		tbl_trans - tbl_trans	# $2a-6 ERROR
	short		tbl_trans - tbl_trans	# $2a-7 ERROR

	short		tbl_trans - tbl_trans	# $2b-0 ERROR
	short		tbl_trans - tbl_trans	# $2b-1 ERROR
	short		tbl_trans - tbl_trans	# $2b-2 ERROR
	short		tbl_trans - tbl_trans	# $2b-3 ERROR
	short		tbl_trans - tbl_trans	# $2b-4 ERROR
	short		tbl_trans - tbl_trans	# $2b-5 ERROR
	short		tbl_trans - tbl_trans	# $2b-6 ERROR
	short		tbl_trans - tbl_trans	# $2b-7 ERROR

	short		tbl_trans - tbl_trans	# $2c-0 ERROR
	short		tbl_trans - tbl_trans	# $2c-1 ERROR
	short		tbl_trans - tbl_trans	# $2c-2 ERROR
	short		tbl_trans - tbl_trans	# $2c-3 ERROR
	short		tbl_trans - tbl_trans	# $2c-4 ERROR
	short		tbl_trans - tbl_trans	# $2c-5 ERROR
	short		tbl_trans - tbl_trans	# $2c-6 ERROR
	short		tbl_trans - tbl_trans	# $2c-7 ERROR

	short		tbl_trans - tbl_trans	# $2d-0 ERROR
	short		tbl_trans - tbl_trans	# $2d-1 ERROR
	short		tbl_trans - tbl_trans	# $2d-2 ERROR
	short		tbl_trans - tbl_trans	# $2d-3 ERROR
	short		tbl_trans - tbl_trans	# $2d-4 ERROR
	short		tbl_trans - tbl_trans	# $2d-5 ERROR
	short		tbl_trans - tbl_trans	# $2d-6 ERROR
	short		tbl_trans - tbl_trans	# $2d-7 ERROR

	short		tbl_trans - tbl_trans	# $2e-0 ERROR
	short		tbl_trans - tbl_trans	# $2e-1 ERROR
	short		tbl_trans - tbl_trans	# $2e-2 ERROR
	short		tbl_trans - tbl_trans	# $2e-3 ERROR
	short		tbl_trans - tbl_trans	# $2e-4 ERROR
	short		tbl_trans - tbl_trans	# $2e-5 ERROR
	short		tbl_trans - tbl_trans	# $2e-6 ERROR
	short		tbl_trans - tbl_trans	# $2e-7 ERROR

	short		tbl_trans - tbl_trans	# $2f-0 ERROR
	short		tbl_trans - tbl_trans	# $2f-1 ERROR
	short		tbl_trans - tbl_trans	# $2f-2 ERROR
	short		tbl_trans - tbl_trans	# $2f-3 ERROR
	short		tbl_trans - tbl_trans	# $2f-4 ERROR
	short		tbl_trans - tbl_trans	# $2f-5 ERROR
	short		tbl_trans - tbl_trans	# $2f-6 ERROR
	short		tbl_trans - tbl_trans	# $2f-7 ERROR

	short		ssincos	 - tbl_trans	# $30-0 fsincos norm
	short		ssincosz - tbl_trans	# $30-1 fsincos zero
	short		ssincosi - tbl_trans	# $30-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $30-3 fsincos qnan
	short		ssincosd - tbl_trans	# $30-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $30-4 fsincos snan
	short		tbl_trans - tbl_trans	# $30-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $30-7 ERROR

	short		ssincos	 - tbl_trans	# $31-0 fsincos norm
	short		ssincosz - tbl_trans	# $31-1 fsincos zero
	short		ssincosi - tbl_trans	# $31-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $31-3 fsincos qnan
	short		ssincosd - tbl_trans	# $31-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $31-4 fsincos snan
	short		tbl_trans - tbl_trans	# $31-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $31-7 ERROR

	short		ssincos	 - tbl_trans	# $32-0 fsincos norm
	short		ssincosz - tbl_trans	# $32-1 fsincos zero
	short		ssincosi - tbl_trans	# $32-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $32-3 fsincos qnan
	short		ssincosd - tbl_trans	# $32-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $32-4 fsincos snan
	short		tbl_trans - tbl_trans	# $32-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $32-7 ERROR

	short		ssincos	 - tbl_trans	# $33-0 fsincos norm
	short		ssincosz - tbl_trans	# $33-1 fsincos zero
	short		ssincosi - tbl_trans	# $33-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $33-3 fsincos qnan
	short		ssincosd - tbl_trans	# $33-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $33-4 fsincos snan
	short		tbl_trans - tbl_trans	# $33-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $33-7 ERROR

	short		ssincos	 - tbl_trans	# $34-0 fsincos norm
	short		ssincosz - tbl_trans	# $34-1 fsincos zero
	short		ssincosi - tbl_trans	# $34-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $34-3 fsincos qnan
	short		ssincosd - tbl_trans	# $34-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $34-4 fsincos snan
	short		tbl_trans - tbl_trans	# $34-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $34-7 ERROR

	short		ssincos	 - tbl_trans	# $35-0 fsincos norm
	short		ssincosz - tbl_trans	# $35-1 fsincos zero
	short		ssincosi - tbl_trans	# $35-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $35-3 fsincos qnan
	short		ssincosd - tbl_trans	# $35-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $35-4 fsincos snan
	short		tbl_trans - tbl_trans	# $35-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $35-7 ERROR

	short		ssincos	 - tbl_trans	# $36-0 fsincos norm
	short		ssincosz - tbl_trans	# $36-1 fsincos zero
	short		ssincosi - tbl_trans	# $36-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $36-3 fsincos qnan
	short		ssincosd - tbl_trans	# $36-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $36-4 fsincos snan
	short		tbl_trans - tbl_trans	# $36-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $36-7 ERROR

	short		ssincos	 - tbl_trans	# $37-0 fsincos norm
	short		ssincosz - tbl_trans	# $37-1 fsincos zero
	short		ssincosi - tbl_trans	# $37-2 fsincos inf
	short		ssincosqnan - tbl_trans	# $37-3 fsincos qnan
	short		ssincosd - tbl_trans	# $37-5 fsincos denorm
	short		ssincossnan - tbl_trans	# $37-4 fsincos snan
	short		tbl_trans - tbl_trans	# $37-6 fsincos unnorm
	short		tbl_trans - tbl_trans	# $37-7 ERROR

##########

# the instruction fetch access for the displacement word for the
# fdbcc emulation failed. here, we create an access error frame
# from the current frame and branch to _real_access().
funimp_iacc:
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1

	mov.l		USER_FPIAR(%a6),EXC_PC(%a6) # store current PC

	unlk		%a6

	mov.l		(%sp),-(%sp)		# store SR,hi(PC)
	mov.w		0x8(%sp),0x4(%sp)	# store lo(PC)
	mov.w		&0x4008,0x6(%sp)	# store voff
	mov.l		0x2(%sp),0x8(%sp)	# store EA
	mov.l		&0x09428001,0xc(%sp)	# store FSLW

	btst		&0x5,(%sp)		# user or supervisor mode?
	beq.b		funimp_iacc_end		# user
	bset		&0x2,0xd(%sp)		# set supervisor TM bit

funimp_iacc_end:
	bra.l		_real_access

#########################################################################
# ssin():     computes the sine of a normalized input			#
# ssind():    computes the sine of a denormalized input			#
# scos():     computes the cosine of a normalized input			#
# scosd():    computes the cosine of a denormalized input		#
# ssincos():  computes the sine and cosine of a normalized input	#
# ssincosd(): computes the sine and cosine of a denormalized input	#
#									#
# INPUT *************************************************************** #
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT ************************************************************** #
#	fp0 = sin(X) or cos(X) 						#
#									#
#    For ssincos(X):							#
#	fp0 = sin(X)							#
#	fp1 = cos(X)							#
#									#
# ACCURACY and MONOTONICITY ******************************************* #
#	The returned result is within 1 ulp in 64 significant bit, i.e.	#
#	within 0.5001 ulp to 53 bits if the result is subsequently 	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#									#
#	SIN and COS:							#
#	1. If SIN is invoked, set AdjN := 0; otherwise, set AdjN := 1.	#
#									#
#	2. If |X| >= 15Pi or |X| < 2**(-40), go to 7.			#
#									#
#	3. Decompose X as X = N(Pi/2) + r where |r| <= Pi/4. Let	#
#		k = N mod 4, so in particular, k = 0,1,2,or 3.		#
#		Overwrite k by k := k + AdjN.				#
#									#
#	4. If k is even, go to 6.					#
#									#
#	5. (k is odd) Set j := (k-1)/2, sgn := (-1)**j. 		#
#		Return sgn*cos(r) where cos(r) is approximated by an 	#
#		even polynomial in r, 1 + r*r*(B1+s*(B2+ ... + s*B8)),	#
#		s = r*r.						#
#		Exit.							#
#									#
#	6. (k is even) Set j := k/2, sgn := (-1)**j. Return sgn*sin(r)	#
#		where sin(r) is approximated by an odd polynomial in r	#
#		r + r*s*(A1+s*(A2+ ... + s*A7)),	s = r*r.	#
#		Exit.							#
#									#
#	7. If |X| > 1, go to 9.						#
#									#
#	8. (|X|<2**(-40)) If SIN is invoked, return X; 			#
#		otherwise return 1.					#
#									#
#	9. Overwrite X by X := X rem 2Pi. Now that |X| <= Pi, 		#
#		go back to 3.						#
#									#
#	SINCOS:								#
#	1. If |X| >= 15Pi or |X| < 2**(-40), go to 6.			#
#									#
#	2. Decompose X as X = N(Pi/2) + r where |r| <= Pi/4. Let	#
#		k = N mod 4, so in particular, k = 0,1,2,or 3.		#
#									#
#	3. If k is even, go to 5.					#
#									#
#	4. (k is odd) Set j1 := (k-1)/2, j2 := j1 (EOR) (k mod 2), ie.	#
#		j1 exclusive or with the l.s.b. of k.			#
#		sgn1 := (-1)**j1, sgn2 := (-1)**j2.			#
#		SIN(X) = sgn1 * cos(r) and COS(X) = sgn2*sin(r) where	#
#		sin(r) and cos(r) are computed as odd and even 		#
#		polynomials in r, respectively. Exit			#
#									#
#	5. (k is even) Set j1 := k/2, sgn1 := (-1)**j1.			#
#		SIN(X) = sgn1 * sin(r) and COS(X) = sgn1*cos(r) where	#
#		sin(r) and cos(r) are computed as odd and even 		#
#		polynomials in r, respectively. Exit			#
#									#
#	6. If |X| > 1, go to 8.						#
#									#
#	7. (|X|<2**(-40)) SIN(X) = X and COS(X) = 1. Exit.		#
#									#
#	8. Overwrite X by X := X rem 2Pi. Now that |X| <= Pi, 		#
#		go back to 2.						#
#									#
#########################################################################

SINA7:	long		0xBD6AAA77,0xCCC994F5
SINA6:	long		0x3DE61209,0x7AAE8DA1
SINA5:	long		0xBE5AE645,0x2A118AE4
SINA4:	long		0x3EC71DE3,0xA5341531
SINA3:	long		0xBF2A01A0,0x1A018B59,0x00000000,0x00000000
SINA2:	long		0x3FF80000,0x88888888,0x888859AF,0x00000000
SINA1:	long		0xBFFC0000,0xAAAAAAAA,0xAAAAAA99,0x00000000

COSB8:	long		0x3D2AC4D0,0xD6011EE3
COSB7:	long		0xBDA9396F,0x9F45AC19
COSB6:	long		0x3E21EED9,0x0612C972
COSB5:	long		0xBE927E4F,0xB79D9FCF
COSB4:	long		0x3EFA01A0,0x1A01D423,0x00000000,0x00000000
COSB3:	long		0xBFF50000,0xB60B60B6,0x0B61D438,0x00000000
COSB2:	long		0x3FFA0000,0xAAAAAAAA,0xAAAAAB5E
COSB1:	long		0xBF000000

	set		INARG,FP_SCR0

	set		X,FP_SCR0
#	set		XDCARE,X+2
	set		XFRAC,X+4

	set		RPRIME,FP_SCR0
	set		SPRIME,FP_SCR1

	set		POSNEG1,L_SCR1
	set		TWOTO63,L_SCR1

	set		ENDFLAG,L_SCR2
	set		INT,L_SCR2

	set		ADJN,L_SCR3

############################################
	global		ssin
ssin:
	mov.l		&0,ADJN(%a6)		# yes; SET ADJN TO 0
	bra.b		SINBGN

############################################
	global		scos
scos:
	mov.l		&1,ADJN(%a6)		# yes; SET ADJN TO 1

############################################
SINBGN:
#--SAVE FPCR, FP1. CHECK IF |X| IS TOO SMALL OR LARGE

	fmov.x		(%a0),%fp0		# LOAD INPUT
	fmov.x		%fp0,X(%a6)		# save input at X

# "COMPACTIFY" X
	mov.l		(%a0),%d1		# put exp in hi word
	mov.w		4(%a0),%d1		# fetch hi(man)
	and.l		&0x7FFFFFFF,%d1		# strip sign

	cmpi.l		%d1,&0x3FD78000		# is |X| >= 2**(-40)?
	bge.b		SOK1			# no
	bra.w		SINSM			# yes; input is very small

SOK1:
	cmp.l		%d1,&0x4004BC7E		# is |X| < 15 PI?
	blt.b		SINMAIN			# no
	bra.w		SREDUCEX		# yes; input is very large

#--THIS IS THE USUAL CASE, |X| <= 15 PI.
#--THE ARGUMENT REDUCTION IS DONE BY TABLE LOOK UP.
SINMAIN:
	fmov.x		%fp0,%fp1
	fmul.d		TWOBYPI(%pc),%fp1 	# X*2/PI

	lea		PITBL+0x200(%pc),%a1 	# TABLE OF N*PI/2, N = -32,...,32

	fmov.l		%fp1,INT(%a6)		# CONVERT TO INTEGER

	mov.l		INT(%a6),%d1		# make a copy of N
	asl.l		&4,%d1			# N *= 16
	add.l		%d1,%a1			# tbl_addr = a1 + (N*16)

# A1 IS THE ADDRESS OF N*PIBY2
# ...WHICH IS IN TWO PIECES Y1 & Y2
	fsub.x		(%a1)+,%fp0 		# X-Y1
	fsub.s		(%a1),%fp0 		# fp0 = R = (X-Y1)-Y2

SINCONT:
#--continuation from REDUCEX

#--GET N+ADJN AND SEE IF SIN(R) OR COS(R) IS NEEDED
	mov.l		INT(%a6),%d1
	add.l		ADJN(%a6),%d1		# SEE IF D0 IS ODD OR EVEN
	ror.l		&1,%d1			# D0 WAS ODD IFF D0 IS NEGATIVE
	cmp.l		%d1,&0
	blt.w		COSPOLY

#--LET J BE THE LEAST SIG. BIT OF D0, LET SGN := (-1)**J.
#--THEN WE RETURN	SGN*SIN(R). SGN*SIN(R) IS COMPUTED BY
#--R' + R'*S*(A1 + S(A2 + S(A3 + S(A4 + ... + SA7)))), WHERE
#--R' = SGN*R, S=R*R. THIS CAN BE REWRITTEN AS
#--R' + R'*S*( [A1+T(A3+T(A5+TA7))] + [S(A2+T(A4+TA6))])
#--WHERE T=S*S.
#--NOTE THAT A3 THROUGH A7 ARE STORED IN DOUBLE PRECISION
#--WHILE A1 AND A2 ARE IN DOUBLE-EXTENDED FORMAT.
SINPOLY:
	fmovm.x		&0x0c,-(%sp)		# save fp2/fp3

	fmov.x		%fp0,X(%a6)		# X IS R
	fmul.x		%fp0,%fp0		# FP0 IS S

	fmov.d		SINA7(%pc),%fp3
	fmov.d		SINA6(%pc),%fp2

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# FP1 IS T

	ror.l		&1,%d1
	and.l		&0x80000000,%d1
# ...LEAST SIG. BIT OF D0 IN SIGN POSITION
	eor.l		%d1,X(%a6)		# X IS NOW R'= SGN*R

	fmul.x		%fp1,%fp3		# TA7
	fmul.x		%fp1,%fp2		# TA6

	fadd.d		SINA5(%pc),%fp3		# A5+TA7
	fadd.d		SINA4(%pc),%fp2		# A4+TA6

	fmul.x		%fp1,%fp3		# T(A5+TA7)
	fmul.x		%fp1,%fp2		# T(A4+TA6)

	fadd.d		SINA3(%pc),%fp3		# A3+T(A5+TA7)
	fadd.x		SINA2(%pc),%fp2		# A2+T(A4+TA6)

	fmul.x		%fp3,%fp1		# T(A3+T(A5+TA7))

	fmul.x		%fp0,%fp2		# S(A2+T(A4+TA6))
	fadd.x		SINA1(%pc),%fp1		# A1+T(A3+T(A5+TA7))
	fmul.x		X(%a6),%fp0		# R'*S

	fadd.x		%fp2,%fp1		# [A1+T(A3+T(A5+TA7))]+[S(A2+T(A4+TA6))]

	fmul.x		%fp1,%fp0		# SIN(R')-R'

	fmovm.x		(%sp)+,&0x30		# restore fp2/fp3

	fmov.l		%d0,%fpcr		# restore users round mode,prec
	fadd.x		X(%a6),%fp0		# last inst - possible exception set
	bra		t_inx2

#--LET J BE THE LEAST SIG. BIT OF D0, LET SGN := (-1)**J.
#--THEN WE RETURN	SGN*COS(R). SGN*COS(R) IS COMPUTED BY
#--SGN + S'*(B1 + S(B2 + S(B3 + S(B4 + ... + SB8)))), WHERE
#--S=R*R AND S'=SGN*S. THIS CAN BE REWRITTEN AS
#--SGN + S'*([B1+T(B3+T(B5+TB7))] + [S(B2+T(B4+T(B6+TB8)))])
#--WHERE T=S*S.
#--NOTE THAT B4 THROUGH B8 ARE STORED IN DOUBLE PRECISION
#--WHILE B2 AND B3 ARE IN DOUBLE-EXTENDED FORMAT, B1 IS -1/2
#--AND IS THEREFORE STORED AS SINGLE PRECISION.
COSPOLY:
	fmovm.x		&0x0c,-(%sp)		# save fp2/fp3

	fmul.x		%fp0,%fp0		# FP0 IS S

	fmov.d		COSB8(%pc),%fp2
	fmov.d		COSB7(%pc),%fp3

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# FP1 IS T

	fmov.x		%fp0,X(%a6)		# X IS S
	ror.l		&1,%d1
	and.l		&0x80000000,%d1
# ...LEAST SIG. BIT OF D0 IN SIGN POSITION

	fmul.x		%fp1,%fp2		# TB8

	eor.l		%d1,X(%a6)		# X IS NOW S'= SGN*S
	and.l		&0x80000000,%d1

	fmul.x		%fp1,%fp3		# TB7

	or.l		&0x3F800000,%d1		# D0 IS SGN IN SINGLE
	mov.l		%d1,POSNEG1(%a6)

	fadd.d		COSB6(%pc),%fp2		# B6+TB8
	fadd.d		COSB5(%pc),%fp3		# B5+TB7

	fmul.x		%fp1,%fp2		# T(B6+TB8)
	fmul.x		%fp1,%fp3		# T(B5+TB7)

	fadd.d		COSB4(%pc),%fp2		# B4+T(B6+TB8)
	fadd.x		COSB3(%pc),%fp3		# B3+T(B5+TB7)

	fmul.x		%fp1,%fp2		# T(B4+T(B6+TB8))
	fmul.x		%fp3,%fp1		# T(B3+T(B5+TB7))

	fadd.x		COSB2(%pc),%fp2		# B2+T(B4+T(B6+TB8))
	fadd.s		COSB1(%pc),%fp1		# B1+T(B3+T(B5+TB7))

	fmul.x		%fp2,%fp0		# S(B2+T(B4+T(B6+TB8)))

	fadd.x		%fp1,%fp0

	fmul.x		X(%a6),%fp0

	fmovm.x		(%sp)+,&0x30		# restore fp2/fp3

	fmov.l		%d0,%fpcr		# restore users round mode,prec
	fadd.s		POSNEG1(%a6),%fp0	# last inst - possible exception set
	bra		t_inx2

##############################################

# SINe: Big OR Small?
#--IF |X| > 15PI, WE USE THE GENERAL ARGUMENT REDUCTION.
#--IF |X| < 2**(-40), RETURN X OR 1.
SINBORS:
	cmp.l		%d1,&0x3FFF8000
	bgt.l		SREDUCEX

SINSM:
	mov.l		ADJN(%a6),%d1
	cmp.l		%d1,&0
	bgt.b		COSTINY

# here, the operation may underflow iff the precision is sgl or dbl.
# extended denorms are handled through another entry point.
SINTINY:
#	mov.w		&0x0000,XDCARE(%a6)	# JUST IN CASE

	fmov.l		%d0,%fpcr		# restore users round mode,prec
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		X(%a6),%fp0		# last inst - possible exception set
	bra		t_catch

COSTINY:
	fmov.s		&0x3F800000,%fp0	# fp0 = 1.0
	fmov.l		%d0,%fpcr		# restore users round mode,prec
	fadd.s 		&0x80800000,%fp0	# last inst - possible exception set
	bra		t_pinx2

################################################
	global		ssind
#--SIN(X) = X FOR DENORMALIZED X
ssind:
	bra		t_extdnrm

############################################
	global		scosd
#--COS(X) = 1 FOR DENORMALIZED X
scosd:
	fmov.s		&0x3F800000,%fp0	# fp0 = 1.0
	bra		t_pinx2

##################################################

	global		ssincos
ssincos:
#--SET ADJN TO 4
	mov.l		&4,ADJN(%a6)

	fmov.x		(%a0),%fp0		# LOAD INPUT
	fmov.x		%fp0,X(%a6)

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	and.l		&0x7FFFFFFF,%d1		# COMPACTIFY X

	cmp.l		%d1,&0x3FD78000		# |X| >= 2**(-40)?
	bge.b		SCOK1
	bra.w		SCSM

SCOK1:
	cmp.l		%d1,&0x4004BC7E		# |X| < 15 PI?
	blt.b		SCMAIN
	bra.w		SREDUCEX


#--THIS IS THE USUAL CASE, |X| <= 15 PI.
#--THE ARGUMENT REDUCTION IS DONE BY TABLE LOOK UP.
SCMAIN:
	fmov.x		%fp0,%fp1

	fmul.d		TWOBYPI(%pc),%fp1	# X*2/PI

	lea		PITBL+0x200(%pc),%a1	# TABLE OF N*PI/2, N = -32,...,32

	fmov.l		%fp1,INT(%a6)		# CONVERT TO INTEGER

	mov.l		INT(%a6),%d1
	asl.l		&4,%d1
	add.l		%d1,%a1			# ADDRESS OF N*PIBY2, IN Y1, Y2

	fsub.x		(%a1)+,%fp0		# X-Y1
	fsub.s		(%a1),%fp0		# FP0 IS R = (X-Y1)-Y2

SCCONT:
#--continuation point from REDUCEX

	mov.l		INT(%a6),%d1
	ror.l		&1,%d1
	cmp.l		%d1,&0			# D0 < 0 IFF N IS ODD
	bge.w		NEVEN

SNODD:
#--REGISTERS SAVED SO FAR: D0, A0, FP2.
	fmovm.x		&0x04,-(%sp)		# save fp2

	fmov.x		%fp0,RPRIME(%a6)
	fmul.x		%fp0,%fp0		# FP0 IS S = R*R
	fmov.d		SINA7(%pc),%fp1		# A7
	fmov.d		COSB8(%pc),%fp2		# B8
	fmul.x		%fp0,%fp1		# SA7
	fmul.x		%fp0,%fp2		# SB8

	mov.l		%d2,-(%sp)
	mov.l		%d1,%d2
	ror.l		&1,%d2
	and.l		&0x80000000,%d2
	eor.l		%d1,%d2
	and.l		&0x80000000,%d2

	fadd.d		SINA6(%pc),%fp1		# A6+SA7
	fadd.d		COSB7(%pc),%fp2		# B7+SB8

	fmul.x		%fp0,%fp1		# S(A6+SA7)
	eor.l		%d2,RPRIME(%a6)
	mov.l		(%sp)+,%d2
	fmul.x		%fp0,%fp2		# S(B7+SB8)
	ror.l		&1,%d1
	and.l		&0x80000000,%d1
	mov.l		&0x3F800000,POSNEG1(%a6)
	eor.l		%d1,POSNEG1(%a6)

	fadd.d		SINA5(%pc),%fp1		# A5+S(A6+SA7)
	fadd.d		COSB6(%pc),%fp2		# B6+S(B7+SB8)

	fmul.x		%fp0,%fp1		# S(A5+S(A6+SA7))
	fmul.x		%fp0,%fp2		# S(B6+S(B7+SB8))
	fmov.x		%fp0,SPRIME(%a6)

	fadd.d		SINA4(%pc),%fp1		# A4+S(A5+S(A6+SA7))
	eor.l		%d1,SPRIME(%a6)
	fadd.d		COSB5(%pc),%fp2		# B5+S(B6+S(B7+SB8))

	fmul.x		%fp0,%fp1		# S(A4+...)
	fmul.x		%fp0,%fp2		# S(B5+...)

	fadd.d		SINA3(%pc),%fp1		# A3+S(A4+...)
	fadd.d		COSB4(%pc),%fp2		# B4+S(B5+...)

	fmul.x		%fp0,%fp1		# S(A3+...)
	fmul.x		%fp0,%fp2		# S(B4+...)

	fadd.x		SINA2(%pc),%fp1		# A2+S(A3+...)
	fadd.x		COSB3(%pc),%fp2		# B3+S(B4+...)

	fmul.x		%fp0,%fp1		# S(A2+...)
	fmul.x		%fp0,%fp2		# S(B3+...)

	fadd.x		SINA1(%pc),%fp1		# A1+S(A2+...)
	fadd.x		COSB2(%pc),%fp2		# B2+S(B3+...)

	fmul.x		%fp0,%fp1		# S(A1+...)
	fmul.x		%fp2,%fp0		# S(B2+...)

	fmul.x		RPRIME(%a6),%fp1	# R'S(A1+...)
	fadd.s		COSB1(%pc),%fp0		# B1+S(B2...)
	fmul.x		SPRIME(%a6),%fp0	# S'(B1+S(B2+...))

	fmovm.x		(%sp)+,&0x20		# restore fp2

	fmov.l		%d0,%fpcr
	fadd.x		RPRIME(%a6),%fp1	# COS(X)
	bsr		sto_cos			# store cosine result
	fadd.s		POSNEG1(%a6),%fp0	# SIN(X)
	bra		t_inx2

NEVEN:
#--REGISTERS SAVED SO FAR: FP2.
	fmovm.x		&0x04,-(%sp)		# save fp2

	fmov.x		%fp0,RPRIME(%a6)
	fmul.x		%fp0,%fp0		# FP0 IS S = R*R

	fmov.d		COSB8(%pc),%fp1		# B8
	fmov.d		SINA7(%pc),%fp2		# A7

	fmul.x		%fp0,%fp1		# SB8
	fmov.x		%fp0,SPRIME(%a6)
	fmul.x		%fp0,%fp2		# SA7

	ror.l		&1,%d1
	and.l		&0x80000000,%d1

	fadd.d		COSB7(%pc),%fp1		# B7+SB8
	fadd.d		SINA6(%pc),%fp2		# A6+SA7

	eor.l		%d1,RPRIME(%a6)
	eor.l		%d1,SPRIME(%a6)

	fmul.x		%fp0,%fp1		# S(B7+SB8)

	or.l		&0x3F800000,%d1
	mov.l		%d1,POSNEG1(%a6)

	fmul.x		%fp0,%fp2		# S(A6+SA7)

	fadd.d		COSB6(%pc),%fp1		# B6+S(B7+SB8)
	fadd.d		SINA5(%pc),%fp2		# A5+S(A6+SA7)

	fmul.x		%fp0,%fp1		# S(B6+S(B7+SB8))
	fmul.x		%fp0,%fp2		# S(A5+S(A6+SA7))

	fadd.d		COSB5(%pc),%fp1		# B5+S(B6+S(B7+SB8))
	fadd.d		SINA4(%pc),%fp2		# A4+S(A5+S(A6+SA7))

	fmul.x		%fp0,%fp1		# S(B5+...)
	fmul.x		%fp0,%fp2		# S(A4+...)

	fadd.d		COSB4(%pc),%fp1		# B4+S(B5+...)
	fadd.d		SINA3(%pc),%fp2		# A3+S(A4+...)

	fmul.x		%fp0,%fp1		# S(B4+...)
	fmul.x		%fp0,%fp2		# S(A3+...)

	fadd.x		COSB3(%pc),%fp1		# B3+S(B4+...)
	fadd.x		SINA2(%pc),%fp2		# A2+S(A3+...)

	fmul.x		%fp0,%fp1		# S(B3+...)
	fmul.x		%fp0,%fp2		# S(A2+...)

	fadd.x		COSB2(%pc),%fp1		# B2+S(B3+...)
	fadd.x		SINA1(%pc),%fp2		# A1+S(A2+...)

	fmul.x		%fp0,%fp1		# S(B2+...)
	fmul.x		%fp2,%fp0		# s(a1+...)


	fadd.s		COSB1(%pc),%fp1		# B1+S(B2...)
	fmul.x		RPRIME(%a6),%fp0	# R'S(A1+...)
	fmul.x		SPRIME(%a6),%fp1	# S'(B1+S(B2+...))

	fmovm.x		(%sp)+,&0x20		# restore fp2

	fmov.l		%d0,%fpcr
	fadd.s		POSNEG1(%a6),%fp1	# COS(X)
	bsr		sto_cos			# store cosine result
	fadd.x		RPRIME(%a6),%fp0	# SIN(X)
	bra		t_inx2

################################################

SCBORS:
	cmp.l		%d1,&0x3FFF8000
	bgt.w		SREDUCEX

################################################

SCSM:
#	mov.w		&0x0000,XDCARE(%a6)
	fmov.s		&0x3F800000,%fp1

	fmov.l		%d0,%fpcr
	fsub.s		&0x00800000,%fp1
	bsr		sto_cos			# store cosine result
	fmov.l		%fpcr,%d0		# d0 must have fpcr,too
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		X(%a6),%fp0
	bra		t_catch

##############################################

	global		ssincosd
#--SIN AND COS OF X FOR DENORMALIZED X
ssincosd:
	mov.l		%d0,-(%sp)		# save d0
	fmov.s		&0x3F800000,%fp1
	bsr		sto_cos			# store cosine result
	mov.l		(%sp)+,%d0		# restore d0
	bra		t_extdnrm

############################################

#--WHEN REDUCEX IS USED, THE CODE WILL INEVITABLY BE SLOW.
#--THIS REDUCTION METHOD, HOWEVER, IS MUCH FASTER THAN USING
#--THE REMAINDER INSTRUCTION WHICH IS NOW IN SOFTWARE.
SREDUCEX:
	fmovm.x		&0x3c,-(%sp)		# save {fp2-fp5}
	mov.l		%d2,-(%sp)		# save d2
	fmov.s		&0x00000000,%fp1	# fp1 = 0

#--If compact form of abs(arg) in d0=$7ffeffff, argument is so large that
#--there is a danger of unwanted overflow in first LOOP iteration.  In this
#--case, reduce argument by one remainder step to make subsequent reduction
#--safe.
	cmp.l		%d1,&0x7ffeffff		# is arg dangerously large?
	bne.b		SLOOP			# no

# yes; create 2**16383*PI/2
	mov.w		&0x7ffe,FP_SCR0_EX(%a6)
	mov.l		&0xc90fdaa2,FP_SCR0_HI(%a6)
	clr.l		FP_SCR0_LO(%a6)

# create low half of 2**16383*PI/2 at FP_SCR1
	mov.w		&0x7fdc,FP_SCR1_EX(%a6)
	mov.l		&0x85a308d3,FP_SCR1_HI(%a6)
	clr.l		FP_SCR1_LO(%a6)

	ftest.x		%fp0			# test sign of argument
	fblt.w		sred_neg

	or.b		&0x80,FP_SCR0_EX(%a6)	# positive arg
	or.b		&0x80,FP_SCR1_EX(%a6)
sred_neg:
	fadd.x		FP_SCR0(%a6),%fp0	# high part of reduction is exact
	fmov.x		%fp0,%fp1		# save high result in fp1
	fadd.x		FP_SCR1(%a6),%fp0	# low part of reduction
	fsub.x		%fp0,%fp1		# determine low component of result
	fadd.x		FP_SCR1(%a6),%fp1	# fp0/fp1 are reduced argument.

#--ON ENTRY, FP0 IS X, ON RETURN, FP0 IS X REM PI/2, |X| <= PI/4.
#--integer quotient will be stored in N
#--Intermeditate remainder is 66-bit long; (R,r) in (FP0,FP1)
SLOOP:
	fmov.x		%fp0,INARG(%a6)		# +-2**K * F, 1 <= F < 2
	mov.w		INARG(%a6),%d1
	mov.l		%d1,%a1			# save a copy of D0
	and.l		&0x00007FFF,%d1
	sub.l		&0x00003FFF,%d1		# d0 = K
	cmp.l		%d1,&28
	ble.b		SLASTLOOP
SCONTLOOP:
	sub.l		&27,%d1			# d0 = L := K-27
	mov.b		&0,ENDFLAG(%a6)
	bra.b		SWORK
SLASTLOOP:
	clr.l		%d1			# d0 = L := 0
	mov.b		&1,ENDFLAG(%a6)

SWORK:
#--FIND THE REMAINDER OF (R,r) W.R.T.	2**L * (PI/2). L IS SO CHOSEN
#--THAT	INT( X * (2/PI) / 2**(L) ) < 2**29.

#--CREATE 2**(-L) * (2/PI), SIGN(INARG)*2**(63),
#--2**L * (PIby2_1), 2**L * (PIby2_2)

	mov.l		&0x00003FFE,%d2		# BIASED EXP OF 2/PI
	sub.l		%d1,%d2			# BIASED EXP OF 2**(-L)*(2/PI)

	mov.l		&0xA2F9836E,FP_SCR0_HI(%a6)
	mov.l		&0x4E44152A,FP_SCR0_LO(%a6)
	mov.w		%d2,FP_SCR0_EX(%a6)	# FP_SCR0 = 2**(-L)*(2/PI)

	fmov.x		%fp0,%fp2
	fmul.x		FP_SCR0(%a6),%fp2	# fp2 = X * 2**(-L)*(2/PI)

#--WE MUST NOW FIND INT(FP2). SINCE WE NEED THIS VALUE IN
#--FLOATING POINT FORMAT, THE TWO FMOVE'S	FMOVE.L FP <--> N
#--WILL BE TOO INEFFICIENT. THE WAY AROUND IT IS THAT
#--(SIGN(INARG)*2**63	+	FP2) - SIGN(INARG)*2**63 WILL GIVE
#--US THE DESIRED VALUE IN FLOATING POINT.
	mov.l		%a1,%d2
	swap		%d2
	and.l		&0x80000000,%d2
	or.l		&0x5F000000,%d2		# d2 = SIGN(INARG)*2**63 IN SGL
	mov.l		%d2,TWOTO63(%a6)
	fadd.s		TWOTO63(%a6),%fp2	# THE FRACTIONAL PART OF FP1 IS ROUNDED
	fsub.s		TWOTO63(%a6),%fp2	# fp2 = N
#	fint.x		%fp2

#--CREATING 2**(L)*Piby2_1 and 2**(L)*Piby2_2
	mov.l		%d1,%d2			# d2 = L

	add.l		&0x00003FFF,%d2		# BIASED EXP OF 2**L * (PI/2)
	mov.w		%d2,FP_SCR0_EX(%a6)
	mov.l		&0xC90FDAA2,FP_SCR0_HI(%a6)
	clr.l		FP_SCR0_LO(%a6)		# FP_SCR0 = 2**(L) * Piby2_1

	add.l		&0x00003FDD,%d1
	mov.w		%d1,FP_SCR1_EX(%a6)
	mov.l		&0x85A308D3,FP_SCR1_HI(%a6)
	clr.l		FP_SCR1_LO(%a6)		# FP_SCR1 = 2**(L) * Piby2_2

	mov.b		ENDFLAG(%a6),%d1

#--We are now ready to perform (R+r) - N*P1 - N*P2, P1 = 2**(L) * Piby2_1 and
#--P2 = 2**(L) * Piby2_2
	fmov.x		%fp2,%fp4		# fp4 = N
	fmul.x		FP_SCR0(%a6),%fp4	# fp4 = W = N*P1
	fmov.x		%fp2,%fp5		# fp5 = N
	fmul.x		FP_SCR1(%a6),%fp5	# fp5 = w = N*P2
	fmov.x		%fp4,%fp3		# fp3 = W = N*P1

#--we want P+p = W+w  but  |p| <= half ulp of P
#--Then, we need to compute  A := R-P   and  a := r-p
	fadd.x		%fp5,%fp3		# fp3 = P
	fsub.x		%fp3,%fp4		# fp4 = W-P

	fsub.x		%fp3,%fp0		# fp0 = A := R - P
	fadd.x		%fp5,%fp4		# fp4 = p = (W-P)+w

	fmov.x		%fp0,%fp3		# fp3 = A
	fsub.x		%fp4,%fp1		# fp1 = a := r - p

#--Now we need to normalize (A,a) to  "new (R,r)" where R+r = A+a but
#--|r| <= half ulp of R.
	fadd.x		%fp1,%fp0		# fp0 = R := A+a
#--No need to calculate r if this is the last loop
	cmp.b		%d1,&0
	bgt.w		SRESTORE

#--Need to calculate r
	fsub.x		%fp0,%fp3		# fp3 = A-R
	fadd.x		%fp3,%fp1		# fp1 = r := (A-R)+a
	bra.w		SLOOP

SRESTORE:
	fmov.l		%fp2,INT(%a6)
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		(%sp)+,&0x3c		# restore {fp2-fp5}

	mov.l		ADJN(%a6),%d1
	cmp.l		%d1,&4

	blt.w		SINCONT
	bra.w		SCCONT

#########################################################################
# stan():  computes the tangent of a normalized input			#
# stand(): computes the tangent of a denormalized input			#
#									#
# INPUT *************************************************************** #
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT ************************************************************** #
#	fp0 = tan(X)							#
#									#
# ACCURACY and MONOTONICITY ******************************************* #
#	The returned result is within 3 ulp in 64 significant bit, i.e. #
#	within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM *********************************************************** #
#									#
#	1. If |X| >= 15Pi or |X| < 2**(-40), go to 6.			#
#									#
#	2. Decompose X as X = N(Pi/2) + r where |r| <= Pi/4. Let	#
#		k = N mod 2, so in particular, k = 0 or 1.		#
#									#
#	3. If k is odd, go to 5.					#
#									#
#	4. (k is even) Tan(X) = tan(r) and tan(r) is approximated by a	#
#		rational function U/V where				#
#		U = r + r*s*(P1 + s*(P2 + s*P3)), and			#
#		V = 1 + s*(Q1 + s*(Q2 + s*(Q3 + s*Q4))),  s = r*r.	#
#		Exit.							#
#									#
#	4. (k is odd) Tan(X) = -cot(r). Since tan(r) is approximated by #
#		a rational function U/V where				#
#		U = r + r*s*(P1 + s*(P2 + s*P3)), and			#
#		V = 1 + s*(Q1 + s*(Q2 + s*(Q3 + s*Q4))), s = r*r,	#
#		-Cot(r) = -V/U. Exit.					#
#									#
#	6. If |X| > 1, go to 8.						#
#									#
#	7. (|X|<2**(-40)) Tan(X) = X. Exit.				#
#									#
#	8. Overwrite X by X := X rem 2Pi. Now that |X| <= Pi, go back 	#
#		to 2.							#
#									#
#########################################################################

TANQ4:
	long		0x3EA0B759,0xF50F8688
TANP3:
	long		0xBEF2BAA5,0xA8924F04

TANQ3:
	long		0xBF346F59,0xB39BA65F,0x00000000,0x00000000

TANP2:
	long		0x3FF60000,0xE073D3FC,0x199C4A00,0x00000000

TANQ2:
	long		0x3FF90000,0xD23CD684,0x15D95FA1,0x00000000

TANP1:
	long		0xBFFC0000,0x8895A6C5,0xFB423BCA,0x00000000

TANQ1:
	long		0xBFFD0000,0xEEF57E0D,0xA84BC8CE,0x00000000

INVTWOPI:
	long		0x3FFC0000,0xA2F9836E,0x4E44152A,0x00000000

TWOPI1:
	long		0x40010000,0xC90FDAA2,0x00000000,0x00000000
TWOPI2:
	long		0x3FDF0000,0x85A308D4,0x00000000,0x00000000

#--N*PI/2, -32 <= N <= 32, IN A LEADING TERM IN EXT. AND TRAILING
#--TERM IN SGL. NOTE THAT PI IS 64-BIT LONG, THUS N*PI/2 IS AT
#--MOST 69 BITS LONG.
#	global		PITBL
PITBL:
	long		0xC0040000,0xC90FDAA2,0x2168C235,0x21800000
	long		0xC0040000,0xC2C75BCD,0x105D7C23,0xA0D00000
	long		0xC0040000,0xBC7EDCF7,0xFF523611,0xA1E80000
	long		0xC0040000,0xB6365E22,0xEE46F000,0x21480000
	long		0xC0040000,0xAFEDDF4D,0xDD3BA9EE,0xA1200000
	long		0xC0040000,0xA9A56078,0xCC3063DD,0x21FC0000
	long		0xC0040000,0xA35CE1A3,0xBB251DCB,0x21100000
	long		0xC0040000,0x9D1462CE,0xAA19D7B9,0xA1580000
	long		0xC0040000,0x96CBE3F9,0x990E91A8,0x21E00000
	long		0xC0040000,0x90836524,0x88034B96,0x20B00000
	long		0xC0040000,0x8A3AE64F,0x76F80584,0xA1880000
	long		0xC0040000,0x83F2677A,0x65ECBF73,0x21C40000
	long		0xC0030000,0xFB53D14A,0xA9C2F2C2,0x20000000
	long		0xC0030000,0xEEC2D3A0,0x87AC669F,0x21380000
	long		0xC0030000,0xE231D5F6,0x6595DA7B,0xA1300000
	long		0xC0030000,0xD5A0D84C,0x437F4E58,0x9FC00000
	long		0xC0030000,0xC90FDAA2,0x2168C235,0x21000000
	long		0xC0030000,0xBC7EDCF7,0xFF523611,0xA1680000
	long		0xC0030000,0xAFEDDF4D,0xDD3BA9EE,0xA0A00000
	long		0xC0030000,0xA35CE1A3,0xBB251DCB,0x20900000
	long		0xC0030000,0x96CBE3F9,0x990E91A8,0x21600000
	long		0xC0030000,0x8A3AE64F,0x76F80584,0xA1080000
	long		0xC0020000,0xFB53D14A,0xA9C2F2C2,0x1F800000
	long		0xC0020000,0xE231D5F6,0x6595DA7B,0xA0B00000
	long		0xC0020000,0xC90FDAA2,0x2168C235,0x20800000
	long		0xC0020000,0xAFEDDF4D,0xDD3BA9EE,0xA0200000
	long		0xC0020000,0x96CBE3F9,0x990E91A8,0x20E00000
	long		0xC0010000,0xFB53D14A,0xA9C2F2C2,0x1F000000
	long		0xC0010000,0xC90FDAA2,0x2168C235,0x20000000
	long		0xC0010000,0x96CBE3F9,0x990E91A8,0x20600000
	long		0xC0000000,0xC90FDAA2,0x2168C235,0x1F800000
	long		0xBFFF0000,0xC90FDAA2,0x2168C235,0x1F000000
	long		0x00000000,0x00000000,0x00000000,0x00000000
	long		0x3FFF0000,0xC90FDAA2,0x2168C235,0x9F000000
	long		0x40000000,0xC90FDAA2,0x2168C235,0x9F800000
	long		0x40010000,0x96CBE3F9,0x990E91A8,0xA0600000
	long		0x40010000,0xC90FDAA2,0x2168C235,0xA0000000
	long		0x40010000,0xFB53D14A,0xA9C2F2C2,0x9F000000
	long		0x40020000,0x96CBE3F9,0x990E91A8,0xA0E00000
	long		0x40020000,0xAFEDDF4D,0xDD3BA9EE,0x20200000
	long		0x40020000,0xC90FDAA2,0x2168C235,0xA0800000
	long		0x40020000,0xE231D5F6,0x6595DA7B,0x20B00000
	long		0x40020000,0xFB53D14A,0xA9C2F2C2,0x9F800000
	long		0x40030000,0x8A3AE64F,0x76F80584,0x21080000
	long		0x40030000,0x96CBE3F9,0x990E91A8,0xA1600000
	long		0x40030000,0xA35CE1A3,0xBB251DCB,0xA0900000
	long		0x40030000,0xAFEDDF4D,0xDD3BA9EE,0x20A00000
	long		0x40030000,0xBC7EDCF7,0xFF523611,0x21680000
	long		0x40030000,0xC90FDAA2,0x2168C235,0xA1000000
	long		0x40030000,0xD5A0D84C,0x437F4E58,0x1FC00000
	long		0x40030000,0xE231D5F6,0x6595DA7B,0x21300000
	long		0x40030000,0xEEC2D3A0,0x87AC669F,0xA1380000
	long		0x40030000,0xFB53D14A,0xA9C2F2C2,0xA0000000
	long		0x40040000,0x83F2677A,0x65ECBF73,0xA1C40000
	long		0x40040000,0x8A3AE64F,0x76F80584,0x21880000
	long		0x40040000,0x90836524,0x88034B96,0xA0B00000
	long		0x40040000,0x96CBE3F9,0x990E91A8,0xA1E00000
	long		0x40040000,0x9D1462CE,0xAA19D7B9,0x21580000
	long		0x40040000,0xA35CE1A3,0xBB251DCB,0xA1100000
	long		0x40040000,0xA9A56078,0xCC3063DD,0xA1FC0000
	long		0x40040000,0xAFEDDF4D,0xDD3BA9EE,0x21200000
	long		0x40040000,0xB6365E22,0xEE46F000,0xA1480000
	long		0x40040000,0xBC7EDCF7,0xFF523611,0x21E80000
	long		0x40040000,0xC2C75BCD,0x105D7C23,0x20D00000
	long		0x40040000,0xC90FDAA2,0x2168C235,0xA1800000

	set		INARG,FP_SCR0

	set		TWOTO63,L_SCR1
	set		INT,L_SCR1
	set		ENDFLAG,L_SCR2

	global		stan
stan:
	fmov.x		(%a0),%fp0		# LOAD INPUT

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	and.l		&0x7FFFFFFF,%d1

	cmp.l		%d1,&0x3FD78000		# |X| >= 2**(-40)?
	bge.b		TANOK1
	bra.w		TANSM
TANOK1:
	cmp.l		%d1,&0x4004BC7E		# |X| < 15 PI?
	blt.b		TANMAIN
	bra.w		REDUCEX

TANMAIN:
#--THIS IS THE USUAL CASE, |X| <= 15 PI.
#--THE ARGUMENT REDUCTION IS DONE BY TABLE LOOK UP.
	fmov.x		%fp0,%fp1
	fmul.d		TWOBYPI(%pc),%fp1	# X*2/PI

	lea.l		PITBL+0x200(%pc),%a1	# TABLE OF N*PI/2, N = -32,...,32

	fmov.l		%fp1,%d1		# CONVERT TO INTEGER

	asl.l		&4,%d1
	add.l		%d1,%a1			# ADDRESS N*PIBY2 IN Y1, Y2

	fsub.x		(%a1)+,%fp0		# X-Y1

	fsub.s		(%a1),%fp0		# FP0 IS R = (X-Y1)-Y2

	ror.l		&5,%d1
	and.l		&0x80000000,%d1		# D0 WAS ODD IFF D0 < 0

TANCONT:
	fmovm.x		&0x0c,-(%sp)		# save fp2,fp3

	cmp.l		%d1,&0
	blt.w		NODD

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# S = R*R

	fmov.d		TANQ4(%pc),%fp3
	fmov.d		TANP3(%pc),%fp2

	fmul.x		%fp1,%fp3		# SQ4
	fmul.x		%fp1,%fp2		# SP3

	fadd.d		TANQ3(%pc),%fp3		# Q3+SQ4
	fadd.x		TANP2(%pc),%fp2		# P2+SP3

	fmul.x		%fp1,%fp3		# S(Q3+SQ4)
	fmul.x		%fp1,%fp2		# S(P2+SP3)

	fadd.x		TANQ2(%pc),%fp3		# Q2+S(Q3+SQ4)
	fadd.x		TANP1(%pc),%fp2		# P1+S(P2+SP3)

	fmul.x		%fp1,%fp3		# S(Q2+S(Q3+SQ4))
	fmul.x		%fp1,%fp2		# S(P1+S(P2+SP3))

	fadd.x		TANQ1(%pc),%fp3		# Q1+S(Q2+S(Q3+SQ4))
	fmul.x		%fp0,%fp2		# RS(P1+S(P2+SP3))

	fmul.x		%fp3,%fp1		# S(Q1+S(Q2+S(Q3+SQ4)))

	fadd.x		%fp2,%fp0		# R+RS(P1+S(P2+SP3))

	fadd.s		&0x3F800000,%fp1	# 1+S(Q1+...)

	fmovm.x		(%sp)+,&0x30		# restore fp2,fp3

	fmov.l		%d0,%fpcr		# restore users round mode,prec
	fdiv.x		%fp1,%fp0		# last inst - possible exception set
	bra		t_inx2

NODD:
	fmov.x		%fp0,%fp1
	fmul.x		%fp0,%fp0		# S = R*R

	fmov.d		TANQ4(%pc),%fp3
	fmov.d		TANP3(%pc),%fp2

	fmul.x		%fp0,%fp3		# SQ4
	fmul.x		%fp0,%fp2		# SP3

	fadd.d		TANQ3(%pc),%fp3		# Q3+SQ4
	fadd.x		TANP2(%pc),%fp2		# P2+SP3

	fmul.x		%fp0,%fp3		# S(Q3+SQ4)
	fmul.x		%fp0,%fp2		# S(P2+SP3)

	fadd.x		TANQ2(%pc),%fp3		# Q2+S(Q3+SQ4)
	fadd.x		TANP1(%pc),%fp2		# P1+S(P2+SP3)

	fmul.x		%fp0,%fp3		# S(Q2+S(Q3+SQ4))
	fmul.x		%fp0,%fp2		# S(P1+S(P2+SP3))

	fadd.x		TANQ1(%pc),%fp3		# Q1+S(Q2+S(Q3+SQ4))
	fmul.x		%fp1,%fp2		# RS(P1+S(P2+SP3))

	fmul.x		%fp3,%fp0		# S(Q1+S(Q2+S(Q3+SQ4)))

	fadd.x		%fp2,%fp1		# R+RS(P1+S(P2+SP3))
	fadd.s		&0x3F800000,%fp0	# 1+S(Q1+...)

	fmovm.x		(%sp)+,&0x30		# restore fp2,fp3

	fmov.x		%fp1,-(%sp)
	eor.l		&0x80000000,(%sp)

	fmov.l		%d0,%fpcr		# restore users round mode,prec
	fdiv.x		(%sp)+,%fp0		# last inst - possible exception set
	bra		t_inx2

TANBORS:
#--IF |X| > 15PI, WE USE THE GENERAL ARGUMENT REDUCTION.
#--IF |X| < 2**(-40), RETURN X OR 1.
	cmp.l		%d1,&0x3FFF8000
	bgt.b		REDUCEX

TANSM:
	fmov.x		%fp0,-(%sp)
	fmov.l		%d0,%fpcr		# restore users round mode,prec
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		(%sp)+,%fp0		# last inst - posibble exception set
	bra		t_catch

	global		stand
#--TAN(X) = X FOR DENORMALIZED X
stand:
	bra		t_extdnrm

#--WHEN REDUCEX IS USED, THE CODE WILL INEVITABLY BE SLOW.
#--THIS REDUCTION METHOD, HOWEVER, IS MUCH FASTER THAN USING
#--THE REMAINDER INSTRUCTION WHICH IS NOW IN SOFTWARE.
REDUCEX:
	fmovm.x		&0x3c,-(%sp)		# save {fp2-fp5}
	mov.l		%d2,-(%sp)		# save d2
	fmov.s		&0x00000000,%fp1	# fp1 = 0

#--If compact form of abs(arg) in d0=$7ffeffff, argument is so large that
#--there is a danger of unwanted overflow in first LOOP iteration.  In this
#--case, reduce argument by one remainder step to make subsequent reduction
#--safe.
	cmp.l		%d1,&0x7ffeffff		# is arg dangerously large?
	bne.b		LOOP			# no

# yes; create 2**16383*PI/2
	mov.w		&0x7ffe,FP_SCR0_EX(%a6)
	mov.l		&0xc90fdaa2,FP_SCR0_HI(%a6)
	clr.l		FP_SCR0_LO(%a6)

# create low half of 2**16383*PI/2 at FP_SCR1
	mov.w		&0x7fdc,FP_SCR1_EX(%a6)
	mov.l		&0x85a308d3,FP_SCR1_HI(%a6)
	clr.l		FP_SCR1_LO(%a6)

	ftest.x		%fp0			# test sign of argument
	fblt.w		red_neg

	or.b		&0x80,FP_SCR0_EX(%a6)	# positive arg
	or.b		&0x80,FP_SCR1_EX(%a6)
red_neg:
	fadd.x		FP_SCR0(%a6),%fp0	# high part of reduction is exact
	fmov.x		%fp0,%fp1		# save high result in fp1
	fadd.x		FP_SCR1(%a6),%fp0	# low part of reduction
	fsub.x		%fp0,%fp1		# determine low component of result
	fadd.x		FP_SCR1(%a6),%fp1	# fp0/fp1 are reduced argument.

#--ON ENTRY, FP0 IS X, ON RETURN, FP0 IS X REM PI/2, |X| <= PI/4.
#--integer quotient will be stored in N
#--Intermeditate remainder is 66-bit long; (R,r) in (FP0,FP1)
LOOP:
	fmov.x		%fp0,INARG(%a6)		# +-2**K * F, 1 <= F < 2
	mov.w		INARG(%a6),%d1
	mov.l		%d1,%a1			# save a copy of D0
	and.l		&0x00007FFF,%d1
	sub.l		&0x00003FFF,%d1		# d0 = K
	cmp.l		%d1,&28
	ble.b		LASTLOOP
CONTLOOP:
	sub.l		&27,%d1			# d0 = L := K-27
	mov.b		&0,ENDFLAG(%a6)
	bra.b		WORK
LASTLOOP:
	clr.l		%d1			# d0 = L := 0
	mov.b		&1,ENDFLAG(%a6)

WORK:
#--FIND THE REMAINDER OF (R,r) W.R.T.	2**L * (PI/2). L IS SO CHOSEN
#--THAT	INT( X * (2/PI) / 2**(L) ) < 2**29.

#--CREATE 2**(-L) * (2/PI), SIGN(INARG)*2**(63),
#--2**L * (PIby2_1), 2**L * (PIby2_2)

	mov.l		&0x00003FFE,%d2		# BIASED EXP OF 2/PI
	sub.l		%d1,%d2			# BIASED EXP OF 2**(-L)*(2/PI)

	mov.l		&0xA2F9836E,FP_SCR0_HI(%a6)
	mov.l		&0x4E44152A,FP_SCR0_LO(%a6)
	mov.w		%d2,FP_SCR0_EX(%a6)	# FP_SCR0 = 2**(-L)*(2/PI)

	fmov.x		%fp0,%fp2
	fmul.x		FP_SCR0(%a6),%fp2	# fp2 = X * 2**(-L)*(2/PI)

#--WE MUST NOW FIND INT(FP2). SINCE WE NEED THIS VALUE IN
#--FLOATING POINT FORMAT, THE TWO FMOVE'S	FMOVE.L FP <--> N
#--WILL BE TOO INEFFICIENT. THE WAY AROUND IT IS THAT
#--(SIGN(INARG)*2**63	+	FP2) - SIGN(INARG)*2**63 WILL GIVE
#--US THE DESIRED VALUE IN FLOATING POINT.
	mov.l		%a1,%d2
	swap		%d2
	and.l		&0x80000000,%d2
	or.l		&0x5F000000,%d2		# d2 = SIGN(INARG)*2**63 IN SGL
	mov.l		%d2,TWOTO63(%a6)
	fadd.s		TWOTO63(%a6),%fp2	# THE FRACTIONAL PART OF FP1 IS ROUNDED
	fsub.s		TWOTO63(%a6),%fp2	# fp2 = N
#	fintrz.x	%fp2,%fp2

#--CREATING 2**(L)*Piby2_1 and 2**(L)*Piby2_2
	mov.l		%d1,%d2			# d2 = L

	add.l		&0x00003FFF,%d2		# BIASED EXP OF 2**L * (PI/2)
	mov.w		%d2,FP_SCR0_EX(%a6)
	mov.l		&0xC90FDAA2,FP_SCR0_HI(%a6)
	clr.l		FP_SCR0_LO(%a6)		# FP_SCR0 = 2**(L) * Piby2_1

	add.l		&0x00003FDD,%d1
	mov.w		%d1,FP_SCR1_EX(%a6)
	mov.l		&0x85A308D3,FP_SCR1_HI(%a6)
	clr.l		FP_SCR1_LO(%a6)		# FP_SCR1 = 2**(L) * Piby2_2

	mov.b		ENDFLAG(%a6),%d1

#--We are now ready to perform (R+r) - N*P1 - N*P2, P1 = 2**(L) * Piby2_1 and
#--P2 = 2**(L) * Piby2_2
	fmov.x		%fp2,%fp4		# fp4 = N
	fmul.x		FP_SCR0(%a6),%fp4	# fp4 = W = N*P1
	fmov.x		%fp2,%fp5		# fp5 = N
	fmul.x		FP_SCR1(%a6),%fp5	# fp5 = w = N*P2
	fmov.x		%fp4,%fp3		# fp3 = W = N*P1

#--we want P+p = W+w  but  |p| <= half ulp of P
#--Then, we need to compute  A := R-P   and  a := r-p
	fadd.x		%fp5,%fp3		# fp3 = P
	fsub.x		%fp3,%fp4		# fp4 = W-P

	fsub.x		%fp3,%fp0		# fp0 = A := R - P
	fadd.x		%fp5,%fp4		# fp4 = p = (W-P)+w

	fmov.x		%fp0,%fp3		# fp3 = A
	fsub.x		%fp4,%fp1		# fp1 = a := r - p

#--Now we need to normalize (A,a) to  "new (R,r)" where R+r = A+a but
#--|r| <= half ulp of R.
	fadd.x		%fp1,%fp0		# fp0 = R := A+a
#--No need to calculate r if this is the last loop
	cmp.b		%d1,&0
	bgt.w		RESTORE

#--Need to calculate r
	fsub.x		%fp0,%fp3		# fp3 = A-R
	fadd.x		%fp3,%fp1		# fp1 = r := (A-R)+a
	bra.w		LOOP

RESTORE:
	fmov.l		%fp2,INT(%a6)
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		(%sp)+,&0x3c		# restore {fp2-fp5}

	mov.l		INT(%a6),%d1
	ror.l		&1,%d1

	bra.w		TANCONT

#########################################################################
# satan():  computes the arctangent of a normalized number		#
# satand(): computes the arctangent of a denormalized number		#
#									#
# INPUT	*************************************************************** #
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT ************************************************************** #
#	fp0 = arctan(X)							#
#									#
# ACCURACY and MONOTONICITY ******************************************* #
#	The returned result is within 2 ulps in	64 significant bit,	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision. 						#
#									#
# ALGORITHM *********************************************************** #
#	Step 1. If |X| >= 16 or |X| < 1/16, go to Step 5.		#
#									#
#	Step 2. Let X = sgn * 2**k * 1.xxxxxxxx...x. 			#
#		Note that k = -4, -3,..., or 3.				#
#		Define F = sgn * 2**k * 1.xxxx1, i.e. the first 5 	#
#		significant bits of X with a bit-1 attached at the 6-th	#
#		bit position. Define u to be u = (X-F) / (1 + X*F).	#
#									#
#	Step 3. Approximate arctan(u) by a polynomial poly.		#
#									#
#	Step 4. Return arctan(F) + poly, arctan(F) is fetched from a 	#
#		table of values calculated beforehand. Exit.		#
#									#
#	Step 5. If |X| >= 16, go to Step 7.				#
#									#
#	Step 6. Approximate arctan(X) by an odd polynomial in X. Exit.	#
#									#
#	Step 7. Define X' = -1/X. Approximate arctan(X') by an odd 	#
#		polynomial in X'.					#
#		Arctan(X) = sign(X)*Pi/2 + arctan(X'). Exit.		#
#									#
#########################################################################

ATANA3:	long		0xBFF6687E,0x314987D8
ATANA2:	long		0x4002AC69,0x34A26DB3
ATANA1:	long		0xBFC2476F,0x4E1DA28E

ATANB6:	long		0x3FB34444,0x7F876989
ATANB5:	long		0xBFB744EE,0x7FAF45DB
ATANB4:	long		0x3FBC71C6,0x46940220
ATANB3:	long		0xBFC24924,0x921872F9
ATANB2:	long		0x3FC99999,0x99998FA9
ATANB1:	long		0xBFD55555,0x55555555

ATANC5:	long		0xBFB70BF3,0x98539E6A
ATANC4:	long		0x3FBC7187,0x962D1D7D
ATANC3:	long		0xBFC24924,0x827107B8
ATANC2:	long		0x3FC99999,0x9996263E
ATANC1:	long		0xBFD55555,0x55555536

PPIBY2:	long		0x3FFF0000,0xC90FDAA2,0x2168C235,0x00000000
NPIBY2:	long		0xBFFF0000,0xC90FDAA2,0x2168C235,0x00000000

PTINY:	long		0x00010000,0x80000000,0x00000000,0x00000000
NTINY:	long		0x80010000,0x80000000,0x00000000,0x00000000

ATANTBL:
	long		0x3FFB0000,0x83D152C5,0x060B7A51,0x00000000
	long		0x3FFB0000,0x8BC85445,0x65498B8B,0x00000000
	long		0x3FFB0000,0x93BE4060,0x17626B0D,0x00000000
	long		0x3FFB0000,0x9BB3078D,0x35AEC202,0x00000000
	long		0x3FFB0000,0xA3A69A52,0x5DDCE7DE,0x00000000
	long		0x3FFB0000,0xAB98E943,0x62765619,0x00000000
	long		0x3FFB0000,0xB389E502,0xF9C59862,0x00000000
	long		0x3FFB0000,0xBB797E43,0x6B09E6FB,0x00000000
	long		0x3FFB0000,0xC367A5C7,0x39E5F446,0x00000000
	long		0x3FFB0000,0xCB544C61,0xCFF7D5C6,0x00000000
	long		0x3FFB0000,0xD33F62F8,0x2488533E,0x00000000
	long		0x3FFB0000,0xDB28DA81,0x62404C77,0x00000000
	long		0x3FFB0000,0xE310A407,0x8AD34F18,0x00000000
	long		0x3FFB0000,0xEAF6B0A8,0x188EE1EB,0x00000000
	long		0x3FFB0000,0xF2DAF194,0x9DBE79D5,0x00000000
	long		0x3FFB0000,0xFABD5813,0x61D47E3E,0x00000000
	long		0x3FFC0000,0x8346AC21,0x0959ECC4,0x00000000
	long		0x3FFC0000,0x8B232A08,0x304282D8,0x00000000
	long		0x3FFC0000,0x92FB70B8,0xD29AE2F9,0x00000000
	long		0x3FFC0000,0x9ACF476F,0x5CCD1CB4,0x00000000
	long		0x3FFC0000,0xA29E7630,0x4954F23F,0x00000000
	long		0x3FFC0000,0xAA68C5D0,0x8AB85230,0x00000000
	long		0x3FFC0000,0xB22DFFFD,0x9D539F83,0x00000000
	long		0x3FFC0000,0xB9EDEF45,0x3E900EA5,0x00000000
	long		0x3FFC0000,0xC1A85F1C,0xC75E3EA5,0x00000000
	long		0x3FFC0000,0xC95D1BE8,0x28138DE6,0x00000000
	long		0x3FFC0000,0xD10BF300,0x840D2DE4,0x00000000
	long		0x3FFC0000,0xD8B4B2BA,0x6BC05E7A,0x00000000
	long		0x3FFC0000,0xE0572A6B,0xB42335F6,0x00000000
	long		0x3FFC0000,0xE7F32A70,0xEA9CAA8F,0x00000000
	long		0x3FFC0000,0xEF888432,0x64ECEFAA,0x00000000
	long		0x3FFC0000,0xF7170A28,0xECC06666,0x00000000
	long		0x3FFD0000,0x812FD288,0x332DAD32,0x00000000
	long		0x3FFD0000,0x88A8D1B1,0x218E4D64,0x00000000
	long		0x3FFD0000,0x9012AB3F,0x23E4AEE8,0x00000000
	long		0x3FFD0000,0x976CC3D4,0x11E7F1B9,0x00000000
	long		0x3FFD0000,0x9EB68949,0x3889A227,0x00000000
	long		0x3FFD0000,0xA5EF72C3,0x4487361B,0x00000000
	long		0x3FFD0000,0xAD1700BA,0xF07A7227,0x00000000
	long		0x3FFD0000,0xB42CBCFA,0xFD37EFB7,0x00000000
	long		0x3FFD0000,0xBB303A94,0x0BA80F89,0x00000000
	long		0x3FFD0000,0xC22115C6,0xFCAEBBAF,0x00000000
	long		0x3FFD0000,0xC8FEF3E6,0x86331221,0x00000000
	long		0x3FFD0000,0xCFC98330,0xB4000C70,0x00000000
	long		0x3FFD0000,0xD6807AA1,0x102C5BF9,0x00000000
	long		0x3FFD0000,0xDD2399BC,0x31252AA3,0x00000000
	long		0x3FFD0000,0xE3B2A855,0x6B8FC517,0x00000000
	long		0x3FFD0000,0xEA2D764F,0x64315989,0x00000000
	long		0x3FFD0000,0xF3BF5BF8,0xBAD1A21D,0x00000000
	long		0x3FFE0000,0x801CE39E,0x0D205C9A,0x00000000
	long		0x3FFE0000,0x8630A2DA,0xDA1ED066,0x00000000
	long		0x3FFE0000,0x8C1AD445,0xF3E09B8C,0x00000000
	long		0x3FFE0000,0x91DB8F16,0x64F350E2,0x00000000
	long		0x3FFE0000,0x97731420,0x365E538C,0x00000000
	long		0x3FFE0000,0x9CE1C8E6,0xA0B8CDBA,0x00000000
	long		0x3FFE0000,0xA22832DB,0xCADAAE09,0x00000000
	long		0x3FFE0000,0xA746F2DD,0xB7602294,0x00000000
	long		0x3FFE0000,0xAC3EC0FB,0x997DD6A2,0x00000000
	long		0x3FFE0000,0xB110688A,0xEBDC6F6A,0x00000000
	long		0x3FFE0000,0xB5BCC490,0x59ECC4B0,0x00000000
	long		0x3FFE0000,0xBA44BC7D,0xD470782F,0x00000000
	long		0x3FFE0000,0xBEA94144,0xFD049AAC,0x00000000
	long		0x3FFE0000,0xC2EB4ABB,0x661628B6,0x00000000
	long		0x3FFE0000,0xC70BD54C,0xE602EE14,0x00000000
	long		0x3FFE0000,0xCD000549,0xADEC7159,0x00000000
	long		0x3FFE0000,0xD48457D2,0xD8EA4EA3,0x00000000
	long		0x3FFE0000,0xDB948DA7,0x12DECE3B,0x00000000
	long		0x3FFE0000,0xE23855F9,0x69E8096A,0x00000000
	long		0x3FFE0000,0xE8771129,0xC4353259,0x00000000
	long		0x3FFE0000,0xEE57C16E,0x0D379C0D,0x00000000
	long		0x3FFE0000,0xF3E10211,0xA87C3779,0x00000000
	long		0x3FFE0000,0xF919039D,0x758B8D41,0x00000000
	long		0x3FFE0000,0xFE058B8F,0x64935FB3,0x00000000
	long		0x3FFF0000,0x8155FB49,0x7B685D04,0x00000000
	long		0x3FFF0000,0x83889E35,0x49D108E1,0x00000000
	long		0x3FFF0000,0x859CFA76,0x511D724B,0x00000000
	long		0x3FFF0000,0x87952ECF,0xFF8131E7,0x00000000
	long		0x3FFF0000,0x89732FD1,0x9557641B,0x00000000
	long		0x3FFF0000,0x8B38CAD1,0x01932A35,0x00000000
	long		0x3FFF0000,0x8CE7A8D8,0x301EE6B5,0x00000000
	long		0x3FFF0000,0x8F46A39E,0x2EAE5281,0x00000000
	long		0x3FFF0000,0x922DA7D7,0x91888487,0x00000000
	long		0x3FFF0000,0x94D19FCB,0xDEDF5241,0x00000000
	long		0x3FFF0000,0x973AB944,0x19D2A08B,0x00000000
	long		0x3FFF0000,0x996FF00E,0x08E10B96,0x00000000
	long		0x3FFF0000,0x9B773F95,0x12321DA7,0x00000000
	long		0x3FFF0000,0x9D55CC32,0x0F935624,0x00000000
	long		0x3FFF0000,0x9F100575,0x006CC571,0x00000000
	long		0x3FFF0000,0xA0A9C290,0xD97CC06C,0x00000000
	long		0x3FFF0000,0xA22659EB,0xEBC0630A,0x00000000
	long		0x3FFF0000,0xA388B4AF,0xF6EF0EC9,0x00000000
	long		0x3FFF0000,0xA4D35F10,0x61D292C4,0x00000000
	long		0x3FFF0000,0xA60895DC,0xFBE3187E,0x00000000
	long		0x3FFF0000,0xA72A51DC,0x7367BEAC,0x00000000
	long		0x3FFF0000,0xA83A5153,0x0956168F,0x00000000
	long		0x3FFF0000,0xA93A2007,0x7539546E,0x00000000
	long		0x3FFF0000,0xAA9E7245,0x023B2605,0x00000000
	long		0x3FFF0000,0xAC4C84BA,0x6FE4D58F,0x00000000
	long		0x3FFF0000,0xADCE4A4A,0x606B9712,0x00000000
	long		0x3FFF0000,0xAF2A2DCD,0x8D263C9C,0x00000000
	long		0x3FFF0000,0xB0656F81,0xF22265C7,0x00000000
	long		0x3FFF0000,0xB1846515,0x0F71496A,0x00000000
	long		0x3FFF0000,0xB28AAA15,0x6F9ADA35,0x00000000
	long		0x3FFF0000,0xB37B44FF,0x3766B895,0x00000000
	long		0x3FFF0000,0xB458C3DC,0xE9630433,0x00000000
	long		0x3FFF0000,0xB525529D,0x562246BD,0x00000000
	long		0x3FFF0000,0xB5E2CCA9,0x5F9D88CC,0x00000000
	long		0x3FFF0000,0xB692CADA,0x7ACA1ADA,0x00000000
	long		0x3FFF0000,0xB736AEA7,0xA6925838,0x00000000
	long		0x3FFF0000,0xB7CFAB28,0x7E9F7B36,0x00000000
	long		0x3FFF0000,0xB85ECC66,0xCB219835,0x00000000
	long		0x3FFF0000,0xB8E4FD5A,0x20A593DA,0x00000000
	long		0x3FFF0000,0xB99F41F6,0x4AFF9BB5,0x00000000
	long		0x3FFF0000,0xBA7F1E17,0x842BBE7B,0x00000000
	long		0x3FFF0000,0xBB471285,0x7637E17D,0x00000000
	long		0x3FFF0000,0xBBFABE8A,0x4788DF6F,0x00000000
	long		0x3FFF0000,0xBC9D0FAD,0x2B689D79,0x00000000
	long		0x3FFF0000,0xBD306A39,0x471ECD86,0x00000000
	long		0x3FFF0000,0xBDB6C731,0x856AF18A,0x00000000
	long		0x3FFF0000,0xBE31CAC5,0x02E80D70,0x00000000
	long		0x3FFF0000,0xBEA2D55C,0xE33194E2,0x00000000
	long		0x3FFF0000,0xBF0B10B7,0xC03128F0,0x00000000
	long		0x3FFF0000,0xBF6B7A18,0xDACB778D,0x00000000
	long		0x3FFF0000,0xBFC4EA46,0x63FA18F6,0x00000000
	long		0x3FFF0000,0xC0181BDE,0x8B89A454,0x00000000
	long		0x3FFF0000,0xC065B066,0xCFBF6439,0x00000000
	long		0x3FFF0000,0xC0AE345F,0x56340AE6,0x00000000
	long		0x3FFF0000,0xC0F22291,0x9CB9E6A7,0x00000000

	set		X,FP_SCR0
	set		XDCARE,X+2
	set		XFRAC,X+4
	set		XFRACLO,X+8

	set		ATANF,FP_SCR1
	set		ATANFHI,ATANF+4
	set		ATANFLO,ATANF+8

	global		satan
#--ENTRY POINT FOR ATAN(X), HERE X IS FINITE, NON-ZERO, AND NOT NAN'S
satan:
	fmov.x		(%a0),%fp0		# LOAD INPUT

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	fmov.x		%fp0,X(%a6)
	and.l		&0x7FFFFFFF,%d1

	cmp.l		%d1,&0x3FFB8000		# |X| >= 1/16?
	bge.b		ATANOK1
	bra.w		ATANSM

ATANOK1:
	cmp.l		%d1,&0x4002FFFF		# |X| < 16 ?
	ble.b		ATANMAIN
	bra.w		ATANBIG

#--THE MOST LIKELY CASE, |X| IN [1/16, 16). WE USE TABLE TECHNIQUE
#--THE IDEA IS ATAN(X) = ATAN(F) + ATAN( [X-F] / [1+XF] ).
#--SO IF F IS CHOSEN TO BE CLOSE TO X AND ATAN(F) IS STORED IN
#--A TABLE, ALL WE NEED IS TO APPROXIMATE ATAN(U) WHERE
#--U = (X-F)/(1+XF) IS SMALL (REMEMBER F IS CLOSE TO X). IT IS
#--TRUE THAT A DIVIDE IS NOW NEEDED, BUT THE APPROXIMATION FOR
#--ATAN(U) IS A VERY SHORT POLYNOMIAL AND THE INDEXING TO
#--FETCH F AND SAVING OF REGISTERS CAN BE ALL HIDED UNDER THE
#--DIVIDE. IN THE END THIS METHOD IS MUCH FASTER THAN A TRADITIONAL
#--ONE. NOTE ALSO THAT THE TRADITIONAL SCHEME THAT APPROXIMATE
#--ATAN(X) DIRECTLY WILL NEED TO USE A RATIONAL APPROXIMATION
#--(DIVISION NEEDED) ANYWAY BECAUSE A POLYNOMIAL APPROXIMATION
#--WILL INVOLVE A VERY LONG POLYNOMIAL.

#--NOW WE SEE X AS +-2^K * 1.BBBBBBB....B <- 1. + 63 BITS
#--WE CHOSE F TO BE +-2^K * 1.BBBB1
#--THAT IS IT MATCHES THE EXPONENT AND FIRST 5 BITS OF X, THE
#--SIXTH BITS IS SET TO BE 1. SINCE K = -4, -3, ..., 3, THERE
#--ARE ONLY 8 TIMES 16 = 2^7 = 128 |F|'S. SINCE ATAN(-|F|) IS
#-- -ATAN(|F|), WE NEED TO STORE ONLY ATAN(|F|).

ATANMAIN:

	and.l		&0xF8000000,XFRAC(%a6)	# FIRST 5 BITS
	or.l		&0x04000000,XFRAC(%a6)	# SET 6-TH BIT TO 1
	mov.l		&0x00000000,XFRACLO(%a6) # LOCATION OF X IS NOW F

	fmov.x		%fp0,%fp1		# FP1 IS X
	fmul.x		X(%a6),%fp1		# FP1 IS X*F, NOTE THAT X*F > 0
	fsub.x		X(%a6),%fp0		# FP0 IS X-F
	fadd.s		&0x3F800000,%fp1	# FP1 IS 1 + X*F
	fdiv.x		%fp1,%fp0		# FP0 IS U = (X-F)/(1+X*F)

#--WHILE THE DIVISION IS TAKING ITS TIME, WE FETCH ATAN(|F|)
#--CREATE ATAN(F) AND STORE IT IN ATANF, AND
#--SAVE REGISTERS FP2.

	mov.l		%d2,-(%sp)		# SAVE d2 TEMPORARILY
	mov.l		%d1,%d2			# THE EXP AND 16 BITS OF X
	and.l		&0x00007800,%d1		# 4 VARYING BITS OF F'S FRACTION
	and.l		&0x7FFF0000,%d2		# EXPONENT OF F
	sub.l		&0x3FFB0000,%d2		# K+4
	asr.l		&1,%d2
	add.l		%d2,%d1			# THE 7 BITS IDENTIFYING F
	asr.l		&7,%d1			# INDEX INTO TBL OF ATAN(|F|)
	lea		ATANTBL(%pc),%a1
	add.l		%d1,%a1			# ADDRESS OF ATAN(|F|)
	mov.l		(%a1)+,ATANF(%a6)
	mov.l		(%a1)+,ATANFHI(%a6)
	mov.l		(%a1)+,ATANFLO(%a6)	# ATANF IS NOW ATAN(|F|)
	mov.l		X(%a6),%d1		# LOAD SIGN AND EXPO. AGAIN
	and.l		&0x80000000,%d1		# SIGN(F)
	or.l		%d1,ATANF(%a6)		# ATANF IS NOW SIGN(F)*ATAN(|F|)
	mov.l		(%sp)+,%d2		# RESTORE d2

#--THAT'S ALL I HAVE TO DO FOR NOW,
#--BUT ALAS, THE DIVIDE IS STILL CRANKING!

#--U IN FP0, WE ARE NOW READY TO COMPUTE ATAN(U) AS
#--U + A1*U*V*(A2 + V*(A3 + V)), V = U*U
#--THE POLYNOMIAL MAY LOOK STRANGE, BUT IS NEVERTHELESS CORRECT.
#--THE NATURAL FORM IS U + U*V*(A1 + V*(A2 + V*A3))
#--WHAT WE HAVE HERE IS MERELY	A1 = A3, A2 = A1/A3, A3 = A2/A3.
#--THE REASON FOR THIS REARRANGEMENT IS TO MAKE THE INDEPENDENT
#--PARTS A1*U*V AND (A2 + ... STUFF) MORE LOAD-BALANCED

	fmovm.x		&0x04,-(%sp)		# save fp2

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1
	fmov.d		ATANA3(%pc),%fp2
	fadd.x		%fp1,%fp2		# A3+V
	fmul.x		%fp1,%fp2		# V*(A3+V)
	fmul.x		%fp0,%fp1		# U*V
	fadd.d		ATANA2(%pc),%fp2	# A2+V*(A3+V)
	fmul.d		ATANA1(%pc),%fp1	# A1*U*V
	fmul.x		%fp2,%fp1		# A1*U*V*(A2+V*(A3+V))
	fadd.x		%fp1,%fp0		# ATAN(U), FP1 RELEASED

	fmovm.x 	(%sp)+,&0x20		# restore fp2

	fmov.l		%d0,%fpcr		# restore users rnd mode,prec
	fadd.x		ATANF(%a6),%fp0		# ATAN(X)
	bra		t_inx2

ATANBORS:
#--|X| IS IN d0 IN COMPACT FORM. FP1, d0 SAVED.
#--FP0 IS X AND |X| <= 1/16 OR |X| >= 16.
	cmp.l		%d1,&0x3FFF8000
	bgt.w		ATANBIG			# I.E. |X| >= 16

ATANSM:
#--|X| <= 1/16
#--IF |X| < 2^(-40), RETURN X AS ANSWER. OTHERWISE, APPROXIMATE
#--ATAN(X) BY X + X*Y*(B1+Y*(B2+Y*(B3+Y*(B4+Y*(B5+Y*B6)))))
#--WHICH IS X + X*Y*( [B1+Z*(B3+Z*B5)] + [Y*(B2+Z*(B4+Z*B6)] )
#--WHERE Y = X*X, AND Z = Y*Y.

	cmp.l		%d1,&0x3FD78000
	blt.w		ATANTINY

#--COMPUTE POLYNOMIAL
	fmovm.x		&0x0c,-(%sp)		# save fp2/fp3

	fmul.x		%fp0,%fp0		# FPO IS Y = X*X

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# FP1 IS Z = Y*Y

	fmov.d		ATANB6(%pc),%fp2
	fmov.d		ATANB5(%pc),%fp3

	fmul.x		%fp1,%fp2		# Z*B6
	fmul.x		%fp1,%fp3		# Z*B5

	fadd.d		ATANB4(%pc),%fp2	# B4+Z*B6
	fadd.d		ATANB3(%pc),%fp3	# B3+Z*B5

	fmul.x		%fp1,%fp2		# Z*(B4+Z*B6)
	fmul.x		%fp3,%fp1		# Z*(B3+Z*B5)

	fadd.d		ATANB2(%pc),%fp2	# B2+Z*(B4+Z*B6)
	fadd.d		ATANB1(%pc),%fp1	# B1+Z*(B3+Z*B5)

	fmul.x		%fp0,%fp2		# Y*(B2+Z*(B4+Z*B6))
	fmul.x		X(%a6),%fp0		# X*Y

	fadd.x		%fp2,%fp1		# [B1+Z*(B3+Z*B5)]+[Y*(B2+Z*(B4+Z*B6))]

	fmul.x		%fp1,%fp0		# X*Y*([B1+Z*(B3+Z*B5)]+[Y*(B2+Z*(B4+Z*B6))])

	fmovm.x		(%sp)+,&0x30		# restore fp2/fp3

	fmov.l		%d0,%fpcr		# restore users rnd mode,prec
	fadd.x		X(%a6),%fp0
	bra		t_inx2

ATANTINY:
#--|X| < 2^(-40), ATAN(X) = X

	fmov.l		%d0,%fpcr		# restore users rnd mode,prec
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		X(%a6),%fp0		# last inst - possible exception set

	bra		t_catch

ATANBIG:
#--IF |X| > 2^(100), RETURN	SIGN(X)*(PI/2 - TINY). OTHERWISE,
#--RETURN SIGN(X)*PI/2 + ATAN(-1/X).
	cmp.l		%d1,&0x40638000
	bgt.w		ATANHUGE

#--APPROXIMATE ATAN(-1/X) BY
#--X'+X'*Y*(C1+Y*(C2+Y*(C3+Y*(C4+Y*C5)))), X' = -1/X, Y = X'*X'
#--THIS CAN BE RE-WRITTEN AS
#--X'+X'*Y*( [C1+Z*(C3+Z*C5)] + [Y*(C2+Z*C4)] ), Z = Y*Y.

	fmovm.x		&0x0c,-(%sp)		# save fp2/fp3

	fmov.s		&0xBF800000,%fp1	# LOAD -1
	fdiv.x		%fp0,%fp1		# FP1 IS -1/X

#--DIVIDE IS STILL CRANKING

	fmov.x		%fp1,%fp0		# FP0 IS X'
	fmul.x		%fp0,%fp0		# FP0 IS Y = X'*X'
	fmov.x		%fp1,X(%a6)		# X IS REALLY X'

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# FP1 IS Z = Y*Y

	fmov.d		ATANC5(%pc),%fp3
	fmov.d		ATANC4(%pc),%fp2

	fmul.x		%fp1,%fp3		# Z*C5
	fmul.x		%fp1,%fp2		# Z*B4

	fadd.d		ATANC3(%pc),%fp3	# C3+Z*C5
	fadd.d		ATANC2(%pc),%fp2	# C2+Z*C4

	fmul.x		%fp3,%fp1		# Z*(C3+Z*C5), FP3 RELEASED
	fmul.x		%fp0,%fp2		# Y*(C2+Z*C4)

	fadd.d		ATANC1(%pc),%fp1	# C1+Z*(C3+Z*C5)
	fmul.x		X(%a6),%fp0		# X'*Y

	fadd.x		%fp2,%fp1		# [Y*(C2+Z*C4)]+[C1+Z*(C3+Z*C5)]

	fmul.x		%fp1,%fp0		# X'*Y*([B1+Z*(B3+Z*B5)]
#					...	+[Y*(B2+Z*(B4+Z*B6))])
	fadd.x		X(%a6),%fp0

	fmovm.x		(%sp)+,&0x30		# restore fp2/fp3

	fmov.l		%d0,%fpcr		# restore users rnd mode,prec
	tst.b		(%a0)
	bpl.b		pos_big

neg_big:
	fadd.x		NPIBY2(%pc),%fp0
	bra		t_minx2

pos_big:
	fadd.x		PPIBY2(%pc),%fp0
	bra		t_pinx2

ATANHUGE:
#--RETURN SIGN(X)*(PIBY2 - TINY) = SIGN(X)*PIBY2 - SIGN(X)*TINY
	tst.b		(%a0)
	bpl.b		pos_huge

neg_huge:
	fmov.x		NPIBY2(%pc),%fp0
	fmov.l		%d0,%fpcr
	fadd.x		PTINY(%pc),%fp0
	bra		t_minx2

pos_huge:
	fmov.x		PPIBY2(%pc),%fp0
	fmov.l		%d0,%fpcr
	fadd.x		NTINY(%pc),%fp0
	bra		t_pinx2

	global		satand
#--ENTRY POINT FOR ATAN(X) FOR DENORMALIZED ARGUMENT
satand:
	bra		t_extdnrm

#########################################################################
# sasin():  computes the inverse sine of a normalized input		#
# sasind(): computes the inverse sine of a denormalized input		#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT **************************************************************	# 
#	fp0 = arcsin(X)							#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 3 ulps in	64 significant bit,	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#									#
#	ASIN								#
#	1. If |X| >= 1, go to 3.					#
#									#
#	2. (|X| < 1) Calculate asin(X) by				#
#		z := sqrt( [1-X][1+X] )					#
#		asin(X) = atan( x / z ).				#
#		Exit.							#
#									#
#	3. If |X| > 1, go to 5.						#
#									#
#	4. (|X| = 1) sgn := sign(X), return asin(X) := sgn * Pi/2. Exit.#
#									#
#	5. (|X| > 1) Generate an invalid operation by 0 * infinity.	#
#		Exit.							#
#									#
#########################################################################

	global		sasin
sasin:
	fmov.x		(%a0),%fp0		# LOAD INPUT

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	and.l		&0x7FFFFFFF,%d1
	cmp.l		%d1,&0x3FFF8000
	bge.b		ASINBIG

# This catch is added here for the '060 QSP. Originally, the call to
# satan() would handle this case by causing the exception which would
# not be caught until gen_except(). Now, with the exceptions being 
# detected inside of satan(), the exception would have been handled there
# instead of inside sasin() as expected.
	cmp.l		%d1,&0x3FD78000
	blt.w		ASINTINY

#--THIS IS THE USUAL CASE, |X| < 1
#--ASIN(X) = ATAN( X / SQRT( (1-X)(1+X) ) )

ASINMAIN:
	fmov.s		&0x3F800000,%fp1
	fsub.x		%fp0,%fp1		# 1-X
	fmovm.x		&0x4,-(%sp)		#  {fp2}
	fmov.s		&0x3F800000,%fp2
	fadd.x		%fp0,%fp2		# 1+X
	fmul.x		%fp2,%fp1		# (1+X)(1-X)
	fmovm.x		(%sp)+,&0x20		#  {fp2}
	fsqrt.x		%fp1			# SQRT([1-X][1+X])
	fdiv.x		%fp1,%fp0		# X/SQRT([1-X][1+X])
	fmovm.x		&0x01,-(%sp)		# save X/SQRT(...)
	lea		(%sp),%a0		# pass ptr to X/SQRT(...)
	bsr		satan
	add.l		&0xc,%sp		# clear X/SQRT(...) from stack
	bra		t_inx2

ASINBIG:
	fabs.x		%fp0			# |X|
	fcmp.s		%fp0,&0x3F800000
	fbgt		t_operr			# cause an operr exception

#--|X| = 1, ASIN(X) = +- PI/2.
ASINONE:
	fmov.x		PIBY2(%pc),%fp0
	mov.l		(%a0),%d1
	and.l		&0x80000000,%d1		# SIGN BIT OF X
	or.l		&0x3F800000,%d1		# +-1 IN SGL FORMAT
	mov.l		%d1,-(%sp)		# push SIGN(X) IN SGL-FMT
	fmov.l		%d0,%fpcr
	fmul.s		(%sp)+,%fp0
	bra		t_inx2

#--|X| < 2^(-40), ATAN(X) = X
ASINTINY:
	fmov.l		%d0,%fpcr		# restore users rnd mode,prec
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		(%a0),%fp0		# last inst - possible exception
	bra		t_catch

	global		sasind
#--ASIN(X) = X FOR DENORMALIZED X
sasind:
	bra		t_extdnrm

#########################################################################
# sacos():  computes the inverse cosine of a normalized input		#
# sacosd(): computes the inverse cosine of a denormalized input		#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT ************************************************************** #
#	fp0 = arccos(X)							#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 3 ulps in	64 significant bit,	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM *********************************************************** #
#									#
#	ACOS								#
#	1. If |X| >= 1, go to 3.					#
#									#
#	2. (|X| < 1) Calculate acos(X) by				#
#		z := (1-X) / (1+X)					#
#		acos(X) = 2 * atan( sqrt(z) ).				#
#		Exit.							#
#									#
#	3. If |X| > 1, go to 5.						#
#									#
#	4. (|X| = 1) If X > 0, return 0. Otherwise, return Pi. Exit.	#
#									#
#	5. (|X| > 1) Generate an invalid operation by 0 * infinity.	#
#		Exit.							#
#									#
#########################################################################

	global		sacos
sacos:
	fmov.x		(%a0),%fp0		# LOAD INPUT

	mov.l		(%a0),%d1		# pack exp w/ upper 16 fraction
	mov.w		4(%a0),%d1
	and.l		&0x7FFFFFFF,%d1
	cmp.l		%d1,&0x3FFF8000
	bge.b		ACOSBIG

#--THIS IS THE USUAL CASE, |X| < 1
#--ACOS(X) = 2 * ATAN(	SQRT( (1-X)/(1+X) ) )

ACOSMAIN:
	fmov.s		&0x3F800000,%fp1
	fadd.x		%fp0,%fp1		# 1+X
	fneg.x		%fp0			# -X
	fadd.s		&0x3F800000,%fp0	# 1-X
	fdiv.x		%fp1,%fp0		# (1-X)/(1+X)
	fsqrt.x		%fp0			# SQRT((1-X)/(1+X))
	mov.l		%d0,-(%sp)		# save original users fpcr
	clr.l		%d0
	fmovm.x		&0x01,-(%sp)		# save SQRT(...) to stack
	lea		(%sp),%a0		# pass ptr to sqrt
	bsr		satan			# ATAN(SQRT([1-X]/[1+X]))
	add.l		&0xc,%sp		# clear SQRT(...) from stack

	fmov.l		(%sp)+,%fpcr		# restore users round prec,mode
	fadd.x		%fp0,%fp0		# 2 * ATAN( STUFF )
	bra		t_pinx2

ACOSBIG:
	fabs.x		%fp0
	fcmp.s		%fp0,&0x3F800000
	fbgt		t_operr			# cause an operr exception

#--|X| = 1, ACOS(X) = 0 OR PI
	tst.b		(%a0)			# is X positive or negative?
	bpl.b		ACOSP1

#--X = -1
#Returns PI and inexact exception
ACOSM1:
	fmov.x		PI(%pc),%fp0		# load PI
	fmov.l		%d0,%fpcr		# load round mode,prec
	fadd.s		&0x00800000,%fp0	# add a small value
	bra		t_pinx2

ACOSP1:
	bra		ld_pzero		# answer is positive zero

	global		sacosd
#--ACOS(X) = PI/2 FOR DENORMALIZED X
sacosd:
	fmov.l		%d0,%fpcr		# load user's rnd mode/prec
	fmov.x		PIBY2(%pc),%fp0
	bra		t_pinx2

#########################################################################
# setox():    computes the exponential for a normalized input		#
# setoxd():   computes the exponential for a denormalized input		# 
# setoxm1():  computes the exponential minus 1 for a normalized input	#
# setoxm1d(): computes the exponential minus 1 for a denormalized input	#
#									#
# INPUT	*************************************************************** #
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT ************************************************************** #
#	fp0 = exp(X) or exp(X)-1					#
#									#
# ACCURACY and MONOTONICITY ******************************************* #
#	The returned result is within 0.85 ulps in 64 significant bit, 	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently #
#	rounded to double precision. The result is provably monotonic 	#
#	in double precision.						#
#									#
# ALGORITHM and IMPLEMENTATION **************************************** #
#									#
#	setoxd								#
#	------								#
#	Step 1.	Set ans := 1.0						#
#									#
#	Step 2.	Return	ans := ans + sign(X)*2^(-126). Exit.		#
#	Notes:	This will always generate one exception -- inexact.	#
#									#
#									#
#	setox								#
#	-----								#
#									#
#	Step 1.	Filter out extreme cases of input argument.		#
#		1.1	If |X| >= 2^(-65), go to Step 1.3.		#
#		1.2	Go to Step 7.					#
#		1.3	If |X| < 16380 log(2), go to Step 2.		#
#		1.4	Go to Step 8.					#
#	Notes:	The usual case should take the branches 1.1 -> 1.3 -> 2.#
#		To avoid the use of floating-point comparisons, a	#
#		compact representation of |X| is used. This format is a	#
#		32-bit integer, the upper (more significant) 16 bits 	#
#		are the sign and biased exponent field of |X|; the 	#
#		lower 16 bits are the 16 most significant fraction	#
#		(including the explicit bit) bits of |X|. Consequently,	#
#		the comparisons in Steps 1.1 and 1.3 can be performed	#
#		by integer comparison. Note also that the constant	#
#		16380 log(2) used in Step 1.3 is also in the compact	#
#		form. Thus taking the branch to Step 2 guarantees 	#
#		|X| < 16380 log(2). There is no harm to have a small	#
#		number of cases where |X| is less than,	but close to,	#
#		16380 log(2) and the branch to Step 9 is taken.		#
#									#
#	Step 2.	Calculate N = round-to-nearest-int( X * 64/log2 ).	#
#		2.1	Set AdjFlag := 0 (indicates the branch 1.3 -> 2 #
#			was taken)					#
#		2.2	N := round-to-nearest-integer( X * 64/log2 ).	#
#		2.3	Calculate	J = N mod 64; so J = 0,1,2,..., #
#			or 63.						#
#		2.4	Calculate	M = (N - J)/64; so N = 64M + J.	#
#		2.5	Calculate the address of the stored value of 	#
#			2^(J/64).					#
#		2.6	Create the value Scale = 2^M.			#
#	Notes:	The calculation in 2.2 is really performed by		#
#			Z := X * constant				#
#			N := round-to-nearest-integer(Z)		#
#		where							#
#			constant := single-precision( 64/log 2 ).	#
#									#
#		Using a single-precision constant avoids memory 	#
#		access. Another effect of using a single-precision	#
#		"constant" is that the calculated value Z is 		#
#									#
#			Z = X*(64/log2)*(1+eps), |eps| <= 2^(-24).	#
#									#
#		This error has to be considered later in Steps 3 and 4.	#
#									#
#	Step 3.	Calculate X - N*log2/64.				#
#		3.1	R := X + N*L1, 					#
#				where L1 := single-precision(-log2/64).	#
#		3.2	R := R + N*L2, 					#
#				L2 := extended-precision(-log2/64 - L1).#
#	Notes:	a) The way L1 and L2 are chosen ensures L1+L2 		#
#		approximate the value -log2/64 to 88 bits of accuracy.	#
#		b) N*L1 is exact because N is no longer than 22 bits	#
#		and L1 is no longer than 24 bits.			#
#		c) The calculation X+N*L1 is also exact due to 		#
#		cancellation. Thus, R is practically X+N(L1+L2) to full	#
#		64 bits. 						#
#		d) It is important to estimate how large can |R| be	#
#		after Step 3.2.						#
#									#
#		N = rnd-to-int( X*64/log2 (1+eps) ), |eps|<=2^(-24)	#
#		X*64/log2 (1+eps)	=	N + f,	|f| <= 0.5	#
#		X*64/log2 - N	=	f - eps*X 64/log2		#
#		X - N*log2/64	=	f*log2/64 - eps*X		#
#									#
#									#
#		Now |X| <= 16446 log2, thus				#
#									#
#			|X - N*log2/64| <= (0.5 + 16446/2^(18))*log2/64	#
#					<= 0.57 log2/64.		#
#		 This bound will be used in Step 4.			#
#									#
#	Step 4.	Approximate exp(R)-1 by a polynomial			#
#		p = R + R*R*(A1 + R*(A2 + R*(A3 + R*(A4 + R*A5))))	#
#	Notes:	a) In order to reduce memory access, the coefficients 	#
#		are made as "short" as possible: A1 (which is 1/2), A4	#
#		and A5 are single precision; A2 and A3 are double	#
#		precision. 						#
#		b) Even with the restrictions above, 			#
#		   |p - (exp(R)-1)| < 2^(-68.8) for all |R| <= 0.0062.	#
#		Note that 0.0062 is slightly bigger than 0.57 log2/64.	#
#		c) To fully utilize the pipeline, p is separated into	#
#		two independent pieces of roughly equal complexities	#
#			p = [ R + R*S*(A2 + S*A4) ]	+		#
#				[ S*(A1 + S*(A3 + S*A5)) ]		#
#		where S = R*R.						#
#									#
#	Step 5.	Compute 2^(J/64)*exp(R) = 2^(J/64)*(1+p) by		#
#				ans := T + ( T*p + t)			#
#		where T and t are the stored values for 2^(J/64).	#
#	Notes:	2^(J/64) is stored as T and t where T+t approximates	#
#		2^(J/64) to roughly 85 bits; T is in extended precision	#
#		and t is in single precision. Note also that T is 	#
#		rounded to 62 bits so that the last two bits of T are 	#
#		zero. The reason for such a special form is that T-1, 	#
#		T-2, and T-8 will all be exact --- a property that will	#
#		give much more accurate computation of the function 	#
#		EXPM1.							#
#									#
#	Step 6.	Reconstruction of exp(X)				#
#			exp(X) = 2^M * 2^(J/64) * exp(R).		#
#		6.1	If AdjFlag = 0, go to 6.3			#
#		6.2	ans := ans * AdjScale				#
#		6.3	Restore the user FPCR				#
#		6.4	Return ans := ans * Scale. Exit.		#
#	Notes:	If AdjFlag = 0, we have X = Mlog2 + Jlog2/64 + R,	#
#		|M| <= 16380, and Scale = 2^M. Moreover, exp(X) will	#
#		neither overflow nor underflow. If AdjFlag = 1, that	#
#		means that						#
#			X = (M1+M)log2 + Jlog2/64 + R, |M1+M| >= 16380.	#
#		Hence, exp(X) may overflow or underflow or neither.	#
#		When that is the case, AdjScale = 2^(M1) where M1 is	#
#		approximately M. Thus 6.2 will never cause 		#
#		over/underflow. Possible exception in 6.4 is overflow	#
#		or underflow. The inexact exception is not generated in	#
#		6.4. Although one can argue that the inexact flag	#
#		should always be raised, to simulate that exception 	#
#		cost to much than the flag is worth in practical uses.	#
#									#
#	Step 7.	Return 1 + X.						#
#		7.1	ans := X					#
#		7.2	Restore user FPCR.				#
#		7.3	Return ans := 1 + ans. Exit			#
#	Notes:	For non-zero X, the inexact exception will always be	#
#		raised by 7.3. That is the only exception raised by 7.3.#
#		Note also that we use the FMOVEM instruction to move X	#
#		in Step 7.1 to avoid unnecessary trapping. (Although	#
#		the FMOVEM may not seem relevant since X is normalized,	#
#		the precaution will be useful in the library version of	#
#		this code where the separate entry for denormalized 	#
#		inputs will be done away with.)				#
#									#
#	Step 8.	Handle exp(X) where |X| >= 16380log2.			#
#		8.1	If |X| > 16480 log2, go to Step 9.		#
#		(mimic 2.2 - 2.6)					#
#		8.2	N := round-to-integer( X * 64/log2 )		#
#		8.3	Calculate J = N mod 64, J = 0,1,...,63		#
#		8.4	K := (N-J)/64, M1 := truncate(K/2), M = K-M1, 	#
#			AdjFlag := 1.					#
#		8.5	Calculate the address of the stored value 	#
#			2^(J/64).					#
#		8.6	Create the values Scale = 2^M, AdjScale = 2^M1.	#
#		8.7	Go to Step 3.					#
#	Notes:	Refer to notes for 2.2 - 2.6.				#
#									#
#	Step 9.	Handle exp(X), |X| > 16480 log2.			#
#		9.1	If X < 0, go to 9.3				#
#		9.2	ans := Huge, go to 9.4				#
#		9.3	ans := Tiny.					#
#		9.4	Restore user FPCR.				#
#		9.5	Return ans := ans * ans. Exit.			#
#	Notes:	Exp(X) will surely overflow or underflow, depending on	#
#		X's sign. "Huge" and "Tiny" are respectively large/tiny	#
#		extended-precision numbers whose square over/underflow	#
#		with an inexact result. Thus, 9.5 always raises the	#
#		inexact together with either overflow or underflow.	#
#									#
#	setoxm1d							#
#	--------							#
#									#
#	Step 1.	Set ans := 0						#
#									#
#	Step 2.	Return	ans := X + ans. Exit.				#
#	Notes:	This will return X with the appropriate rounding	#
#		 precision prescribed by the user FPCR.			#
#									#
#	setoxm1								#
#	-------								#
#									#
#	Step 1.	Check |X|						#
#		1.1	If |X| >= 1/4, go to Step 1.3.			#
#		1.2	Go to Step 7.					#
#		1.3	If |X| < 70 log(2), go to Step 2.		#
#		1.4	Go to Step 10.					#
#	Notes:	The usual case should take the branches 1.1 -> 1.3 -> 2.#
#		However, it is conceivable |X| can be small very often	#
#		because EXPM1 is intended to evaluate exp(X)-1 		#
#		accurately when |X| is small. For further details on 	#
#		the comparisons, see the notes on Step 1 of setox.	#
#									#
#	Step 2.	Calculate N = round-to-nearest-int( X * 64/log2 ).	#
#		2.1	N := round-to-nearest-integer( X * 64/log2 ).	#
#		2.2	Calculate	J = N mod 64; so J = 0,1,2,..., #
#			or 63.						#
#		2.3	Calculate	M = (N - J)/64; so N = 64M + J.	#
#		2.4	Calculate the address of the stored value of 	#
#			2^(J/64).					#
#		2.5	Create the values Sc = 2^M and 			#
#			OnebySc := -2^(-M).				#
#	Notes:	See the notes on Step 2 of setox.			#
#									#
#	Step 3.	Calculate X - N*log2/64.				#
#		3.1	R := X + N*L1, 					#
#				where L1 := single-precision(-log2/64).	#
#		3.2	R := R + N*L2, 					#
#				L2 := extended-precision(-log2/64 - L1).#
#	Notes:	Applying the analysis of Step 3 of setox in this case	#
#		shows that |R| <= 0.0055 (note that |X| <= 70 log2 in	#
#		this case).						#
#									#
#	Step 4.	Approximate exp(R)-1 by a polynomial			#
#			p = R+R*R*(A1+R*(A2+R*(A3+R*(A4+R*(A5+R*A6)))))	#
#	Notes:	a) In order to reduce memory access, the coefficients 	#
#		are made as "short" as possible: A1 (which is 1/2), A5 	#
#		and A6 are single precision; A2, A3 and A4 are double 	#
#		precision. 						#
#		b) Even with the restriction above,			#
#			|p - (exp(R)-1)| <	|R| * 2^(-72.7)		#
#		for all |R| <= 0.0055.					#
#		c) To fully utilize the pipeline, p is separated into	#
#		two independent pieces of roughly equal complexity	#
#			p = [ R*S*(A2 + S*(A4 + S*A6)) ]	+	#
#				[ R + S*(A1 + S*(A3 + S*A5)) ]		#
#		where S = R*R.						#
#									#
#	Step 5.	Compute 2^(J/64)*p by					#
#				p := T*p				#
#		where T and t are the stored values for 2^(J/64).	#
#	Notes:	2^(J/64) is stored as T and t where T+t approximates	#
#		2^(J/64) to roughly 85 bits; T is in extended precision	#
#		and t is in single precision. Note also that T is 	#
#		rounded to 62 bits so that the last two bits of T are 	#
#		zero. The reason for such a special form is that T-1, 	#
#		T-2, and T-8 will all be exact --- a property that will	#
#		be exploited in Step 6 below. The total relative error	#
#		in p is no bigger than 2^(-67.7) compared to the final	#
#		result.							#
#									#
#	Step 6.	Reconstruction of exp(X)-1				#
#			exp(X)-1 = 2^M * ( 2^(J/64) + p - 2^(-M) ).	#
#		6.1	If M <= 63, go to Step 6.3.			#
#		6.2	ans := T + (p + (t + OnebySc)). Go to 6.6	#
#		6.3	If M >= -3, go to 6.5.				#
#		6.4	ans := (T + (p + t)) + OnebySc. Go to 6.6	#
#		6.5	ans := (T + OnebySc) + (p + t).			#
#		6.6	Restore user FPCR.				#
#		6.7	Return ans := Sc * ans. Exit.			#
#	Notes:	The various arrangements of the expressions give 	#
#		accurate evaluations.					#
#									#
#	Step 7.	exp(X)-1 for |X| < 1/4.					#
#		7.1	If |X| >= 2^(-65), go to Step 9.		#
#		7.2	Go to Step 8.					#
#									#
#	Step 8.	Calculate exp(X)-1, |X| < 2^(-65).			#
#		8.1	If |X| < 2^(-16312), goto 8.3			#
#		8.2	Restore FPCR; return ans := X - 2^(-16382).	#
#			Exit.						#
#		8.3	X := X * 2^(140).				#
#		8.4	Restore FPCR; ans := ans - 2^(-16382).		#
#		 Return ans := ans*2^(140). Exit			#
#	Notes:	The idea is to return "X - tiny" under the user		#
#		precision and rounding modes. To avoid unnecessary	#
#		inefficiency, we stay away from denormalized numbers 	#
#		the best we can. For |X| >= 2^(-16312), the 		#
#		straightforward 8.2 generates the inexact exception as	#
#		the case warrants.					#
#									#
#	Step 9.	Calculate exp(X)-1, |X| < 1/4, by a polynomial		#
#			p = X + X*X*(B1 + X*(B2 + ... + X*B12))		#
#	Notes:	a) In order to reduce memory access, the coefficients	#
#		are made as "short" as possible: B1 (which is 1/2), B9	#
#		to B12 are single precision; B3 to B8 are double 	#
#		precision; and B2 is double extended.			#
#		b) Even with the restriction above,			#
#			|p - (exp(X)-1)| < |X| 2^(-70.6)		#
#		for all |X| <= 0.251.					#
#		Note that 0.251 is slightly bigger than 1/4.		#
#		c) To fully preserve accuracy, the polynomial is 	#
#		computed as						#
#			X + ( S*B1 +	Q ) where S = X*X and		#
#			Q	=	X*S*(B2 + X*(B3 + ... + X*B12))	#
#		d) To fully utilize the pipeline, Q is separated into	#
#		two independent pieces of roughly equal complexity	#
#			Q = [ X*S*(B2 + S*(B4 + ... + S*B12)) ] +	#
#				[ S*S*(B3 + S*(B5 + ... + S*B11)) ]	#
#									#
#	Step 10. Calculate exp(X)-1 for |X| >= 70 log 2.		#
#		10.1 If X >= 70log2 , exp(X) - 1 = exp(X) for all 	#
#		practical purposes. Therefore, go to Step 1 of setox.	#
#		10.2 If X <= -70log2, exp(X) - 1 = -1 for all practical	#
#		purposes. 						#
#		ans := -1 						#
#		Restore user FPCR					#
#		Return ans := ans + 2^(-126). Exit.			#
#	Notes:	10.2 will always create an inexact and return -1 + tiny	#
#		in the user rounding precision and mode.		#
#									#
#########################################################################

L2:	long		0x3FDC0000,0x82E30865,0x4361C4C6,0x00000000

EEXPA3:	long		0x3FA55555,0x55554CC1
EEXPA2:	long		0x3FC55555,0x55554A54

EM1A4:	long		0x3F811111,0x11174385
EM1A3:	long		0x3FA55555,0x55554F5A

EM1A2:	long		0x3FC55555,0x55555555,0x00000000,0x00000000

EM1B8:	long		0x3EC71DE3,0xA5774682
EM1B7:	long		0x3EFA01A0,0x19D7CB68

EM1B6:	long		0x3F2A01A0,0x1A019DF3
EM1B5:	long		0x3F56C16C,0x16C170E2

EM1B4:	long		0x3F811111,0x11111111
EM1B3:	long		0x3FA55555,0x55555555

EM1B2:	long		0x3FFC0000,0xAAAAAAAA,0xAAAAAAAB
	long		0x00000000

TWO140:	long		0x48B00000,0x00000000
TWON140:
	long		0x37300000,0x00000000

EEXPTBL:
	long		0x3FFF0000,0x80000000,0x00000000,0x00000000
	long		0x3FFF0000,0x8164D1F3,0xBC030774,0x9F841A9B
	long		0x3FFF0000,0x82CD8698,0xAC2BA1D8,0x9FC1D5B9
	long		0x3FFF0000,0x843A28C3,0xACDE4048,0xA0728369
	long		0x3FFF0000,0x85AAC367,0xCC487B14,0x1FC5C95C
	long		0x3FFF0000,0x871F6196,0x9E8D1010,0x1EE85C9F
	long		0x3FFF0000,0x88980E80,0x92DA8528,0x9FA20729
	long		0x3FFF0000,0x8A14D575,0x496EFD9C,0xA07BF9AF
	long		0x3FFF0000,0x8B95C1E3,0xEA8BD6E8,0xA0020DCF
	long		0x3FFF0000,0x8D1ADF5B,0x7E5BA9E4,0x205A63DA
	long		0x3FFF0000,0x8EA4398B,0x45CD53C0,0x1EB70051
	long		0x3FFF0000,0x9031DC43,0x1466B1DC,0x1F6EB029
	long		0x3FFF0000,0x91C3D373,0xAB11C338,0xA0781494
	long		0x3FFF0000,0x935A2B2F,0x13E6E92C,0x9EB319B0
	long		0x3FFF0000,0x94F4EFA8,0xFEF70960,0x2017457D
	long		0x3FFF0000,0x96942D37,0x20185A00,0x1F11D537
	long		0x3FFF0000,0x9837F051,0x8DB8A970,0x9FB952DD
	long		0x3FFF0000,0x99E04593,0x20B7FA64,0x1FE43087
	long		0x3FFF0000,0x9B8D39B9,0xD54E5538,0x1FA2A818
	long		0x3FFF0000,0x9D3ED9A7,0x2CFFB750,0x1FDE494D
	long		0x3FFF0000,0x9EF53260,0x91A111AC,0x20504890
	long		0x3FFF0000,0xA0B0510F,0xB9714FC4,0xA073691C
	long		0x3FFF0000,0xA2704303,0x0C496818,0x1F9B7A05
	long		0x3FFF0000,0xA43515AE,0x09E680A0,0xA0797126
	long		0x3FFF0000,0xA5FED6A9,0xB15138EC,0xA071A140
	long		0x3FFF0000,0xA7CD93B4,0xE9653568,0x204F62DA
	long		0x3FFF0000,0xA9A15AB4,0xEA7C0EF8,0x1F283C4A
	long		0x3FFF0000,0xAB7A39B5,0xA93ED338,0x9F9A7FDC
	long		0x3FFF0000,0xAD583EEA,0x42A14AC8,0xA05B3FAC
	long		0x3FFF0000,0xAF3B78AD,0x690A4374,0x1FDF2610
	long		0x3FFF0000,0xB123F581,0xD2AC2590,0x9F705F90
	long		0x3FFF0000,0xB311C412,0xA9112488,0x201F678A
	long		0x3FFF0000,0xB504F333,0xF9DE6484,0x1F32FB13
	long		0x3FFF0000,0xB6FD91E3,0x28D17790,0x20038B30
	long		0x3FFF0000,0xB8FBAF47,0x62FB9EE8,0x200DC3CC
	long		0x3FFF0000,0xBAFF5AB2,0x133E45FC,0x9F8B2AE6
	long		0x3FFF0000,0xBD08A39F,0x580C36C0,0xA02BBF70
	long		0x3FFF0000,0xBF1799B6,0x7A731084,0xA00BF518
	long		0x3FFF0000,0xC12C4CCA,0x66709458,0xA041DD41
	long		0x3FFF0000,0xC346CCDA,0x24976408,0x9FDF137B
	long		0x3FFF0000,0xC5672A11,0x5506DADC,0x201F1568
	long		0x3FFF0000,0xC78D74C8,0xABB9B15C,0x1FC13A2E
	long		0x3FFF0000,0xC9B9BD86,0x6E2F27A4,0xA03F8F03
	long		0x3FFF0000,0xCBEC14FE,0xF2727C5C,0x1FF4907D
	long		0x3FFF0000,0xCE248C15,0x1F8480E4,0x9E6E53E4
	long		0x3FFF0000,0xD06333DA,0xEF2B2594,0x1FD6D45C
	long		0x3FFF0000,0xD2A81D91,0xF12AE45C,0xA076EDB9
	long		0x3FFF0000,0xD4F35AAB,0xCFEDFA20,0x9FA6DE21
	long		0x3FFF0000,0xD744FCCA,0xD69D6AF4,0x1EE69A2F
	long		0x3FFF0000,0xD99D15C2,0x78AFD7B4,0x207F439F
	long		0x3FFF0000,0xDBFBB797,0xDAF23754,0x201EC207
	long		0x3FFF0000,0xDE60F482,0x5E0E9124,0x9E8BE175
	long		0x3FFF0000,0xE0CCDEEC,0x2A94E110,0x20032C4B
	long		0x3FFF0000,0xE33F8972,0xBE8A5A50,0x2004DFF5
	long		0x3FFF0000,0xE5B906E7,0x7C8348A8,0x1E72F47A
	long		0x3FFF0000,0xE8396A50,0x3C4BDC68,0x1F722F22
	long		0x3FFF0000,0xEAC0C6E7,0xDD243930,0xA017E945
	long		0x3FFF0000,0xED4F301E,0xD9942B84,0x1F401A5B
	long		0x3FFF0000,0xEFE4B99B,0xDCDAF5CC,0x9FB9A9E3
	long		0x3FFF0000,0xF281773C,0x59FFB138,0x20744C05
	long		0x3FFF0000,0xF5257D15,0x2486CC2C,0x1F773A19
	long		0x3FFF0000,0xF7D0DF73,0x0AD13BB8,0x1FFE90D5
	long		0x3FFF0000,0xFA83B2DB,0x722A033C,0xA041ED22
	long		0x3FFF0000,0xFD3E0C0C,0xF486C174,0x1F853F3A

	set		ADJFLAG,L_SCR2
	set		SCALE,FP_SCR0
	set		ADJSCALE,FP_SCR1
	set		SC,FP_SCR0
	set		ONEBYSC,FP_SCR1

	global		setox
setox:
#--entry point for EXP(X), here X is finite, non-zero, and not NaN's

#--Step 1.
	mov.l		(%a0),%d1		# load part of input X
	and.l		&0x7FFF0000,%d1		# biased expo. of X
	cmp.l		%d1,&0x3FBE0000		# 2^(-65)
	bge.b		EXPC1			# normal case
	bra		EXPSM

EXPC1:
#--The case |X| >= 2^(-65)
	mov.w		4(%a0),%d1		# expo. and partial sig. of |X|
	cmp.l		%d1,&0x400CB167		# 16380 log2 trunc. 16 bits
	blt.b		EXPMAIN			# normal case
	bra		EEXPBIG

EXPMAIN:
#--Step 2.
#--This is the normal branch:	2^(-65) <= |X| < 16380 log2.
	fmov.x		(%a0),%fp0		# load input from (a0)

	fmov.x		%fp0,%fp1
	fmul.s		&0x42B8AA3B,%fp0	# 64/log2 * X
	fmovm.x		&0xc,-(%sp)		# save fp2 {%fp2/%fp3}
	mov.l		&0,ADJFLAG(%a6)
	fmov.l		%fp0,%d1		# N = int( X * 64/log2 )
	lea		EEXPTBL(%pc),%a1
	fmov.l		%d1,%fp0		# convert to floating-format

	mov.l		%d1,L_SCR1(%a6)		# save N temporarily
	and.l		&0x3F,%d1		# D0 is J = N mod 64
	lsl.l		&4,%d1
	add.l		%d1,%a1			# address of 2^(J/64)
	mov.l		L_SCR1(%a6),%d1
	asr.l		&6,%d1			# D0 is M
	add.w		&0x3FFF,%d1		# biased expo. of 2^(M)
	mov.w		L2(%pc),L_SCR1(%a6)	# prefetch L2, no need in CB

EXPCONT1:
#--Step 3.
#--fp1,fp2 saved on the stack. fp0 is N, fp1 is X,
#--a0 points to 2^(J/64), D0 is biased expo. of 2^(M)
	fmov.x		%fp0,%fp2
	fmul.s		&0xBC317218,%fp0	# N * L1, L1 = lead(-log2/64)
	fmul.x		L2(%pc),%fp2		# N * L2, L1+L2 = -log2/64
	fadd.x		%fp1,%fp0		# X + N*L1
	fadd.x		%fp2,%fp0		# fp0 is R, reduced arg.

#--Step 4.
#--WE NOW COMPUTE EXP(R)-1 BY A POLYNOMIAL
#-- R + R*R*(A1 + R*(A2 + R*(A3 + R*(A4 + R*A5))))
#--TO FULLY UTILIZE THE PIPELINE, WE COMPUTE S = R*R
#--[R+R*S*(A2+S*A4)] + [S*(A1+S*(A3+S*A5))]

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# fp1 IS S = R*R

	fmov.s		&0x3AB60B70,%fp2	# fp2 IS A5

	fmul.x		%fp1,%fp2		# fp2 IS S*A5
	fmov.x		%fp1,%fp3
	fmul.s		&0x3C088895,%fp3	# fp3 IS S*A4

	fadd.d		EEXPA3(%pc),%fp2	# fp2 IS A3+S*A5
	fadd.d		EEXPA2(%pc),%fp3	# fp3 IS A2+S*A4

	fmul.x		%fp1,%fp2		# fp2 IS S*(A3+S*A5)
	mov.w		%d1,SCALE(%a6)		# SCALE is 2^(M) in extended
	mov.l		&0x80000000,SCALE+4(%a6)
	clr.l		SCALE+8(%a6)

	fmul.x		%fp1,%fp3		# fp3 IS S*(A2+S*A4)

	fadd.s		&0x3F000000,%fp2	# fp2 IS A1+S*(A3+S*A5)
	fmul.x		%fp0,%fp3		# fp3 IS R*S*(A2+S*A4)

	fmul.x		%fp1,%fp2		# fp2 IS S*(A1+S*(A3+S*A5))
	fadd.x		%fp3,%fp0		# fp0 IS R+R*S*(A2+S*A4),

	fmov.x		(%a1)+,%fp1		# fp1 is lead. pt. of 2^(J/64)
	fadd.x		%fp2,%fp0		# fp0 is EXP(R) - 1

#--Step 5
#--final reconstruction process
#--EXP(X) = 2^M * ( 2^(J/64) + 2^(J/64)*(EXP(R)-1) )

	fmul.x		%fp1,%fp0		# 2^(J/64)*(Exp(R)-1)
	fmovm.x		(%sp)+,&0x30		# fp2 restored {%fp2/%fp3}
	fadd.s		(%a1),%fp0		# accurate 2^(J/64)

	fadd.x		%fp1,%fp0		# 2^(J/64) + 2^(J/64)*...
	mov.l		ADJFLAG(%a6),%d1

#--Step 6
	tst.l		%d1
	beq.b		NORMAL
ADJUST:
	fmul.x		ADJSCALE(%a6),%fp0
NORMAL:
	fmov.l		%d0,%fpcr		# restore user FPCR
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.x		SCALE(%a6),%fp0		# multiply 2^(M)
	bra		t_catch

EXPSM:
#--Step 7
	fmovm.x		(%a0),&0x80		# load X
	fmov.l		%d0,%fpcr
	fadd.s		&0x3F800000,%fp0	# 1+X in user mode
	bra		t_pinx2

EEXPBIG:
#--Step 8
	cmp.l		%d1,&0x400CB27C		# 16480 log2
	bgt.b		EXP2BIG
#--Steps 8.2 -- 8.6
	fmov.x		(%a0),%fp0		# load input from (a0)

	fmov.x		%fp0,%fp1
	fmul.s		&0x42B8AA3B,%fp0	# 64/log2 * X
	fmovm.x		&0xc,-(%sp)		# save fp2 {%fp2/%fp3}
	mov.l		&1,ADJFLAG(%a6)
	fmov.l		%fp0,%d1		# N = int( X * 64/log2 )
	lea		EEXPTBL(%pc),%a1
	fmov.l		%d1,%fp0		# convert to floating-format
	mov.l		%d1,L_SCR1(%a6)		# save N temporarily
	and.l		&0x3F,%d1		# D0 is J = N mod 64
	lsl.l		&4,%d1
	add.l		%d1,%a1			# address of 2^(J/64)
	mov.l		L_SCR1(%a6),%d1
	asr.l		&6,%d1			# D0 is K
	mov.l		%d1,L_SCR1(%a6)		# save K temporarily
	asr.l		&1,%d1			# D0 is M1
	sub.l		%d1,L_SCR1(%a6)		# a1 is M
	add.w		&0x3FFF,%d1		# biased expo. of 2^(M1)
	mov.w		%d1,ADJSCALE(%a6)	# ADJSCALE := 2^(M1)
	mov.l		&0x80000000,ADJSCALE+4(%a6)
	clr.l		ADJSCALE+8(%a6)
	mov.l		L_SCR1(%a6),%d1		# D0 is M
	add.w		&0x3FFF,%d1		# biased expo. of 2^(M)
	bra.w		EXPCONT1		# go back to Step 3

EXP2BIG:
#--Step 9
	tst.b		(%a0)			# is X positive or negative?
	bmi		t_unfl2
	bra		t_ovfl2

	global		setoxd
setoxd:
#--entry point for EXP(X), X is denormalized
	mov.l		(%a0),-(%sp)
	andi.l		&0x80000000,(%sp)
	ori.l		&0x00800000,(%sp)	# sign(X)*2^(-126)

	fmov.s		&0x3F800000,%fp0

	fmov.l		%d0,%fpcr
	fadd.s		(%sp)+,%fp0
	bra		t_pinx2

	global		setoxm1
setoxm1:
#--entry point for EXPM1(X), here X is finite, non-zero, non-NaN

#--Step 1.
#--Step 1.1
	mov.l		(%a0),%d1		# load part of input X
	and.l		&0x7FFF0000,%d1		# biased expo. of X
	cmp.l		%d1,&0x3FFD0000		# 1/4
	bge.b		EM1CON1			# |X| >= 1/4
	bra		EM1SM

EM1CON1:
#--Step 1.3
#--The case |X| >= 1/4
	mov.w		4(%a0),%d1		# expo. and partial sig. of |X|
	cmp.l		%d1,&0x4004C215		# 70log2 rounded up to 16 bits
	ble.b		EM1MAIN			# 1/4 <= |X| <= 70log2
	bra		EM1BIG

EM1MAIN:
#--Step 2.
#--This is the case:	1/4 <= |X| <= 70 log2.
	fmov.x		(%a0),%fp0		# load input from (a0)

	fmov.x		%fp0,%fp1
	fmul.s		&0x42B8AA3B,%fp0	# 64/log2 * X
	fmovm.x		&0xc,-(%sp)		# save fp2 {%fp2/%fp3}
	fmov.l		%fp0,%d1		# N = int( X * 64/log2 )
	lea		EEXPTBL(%pc),%a1
	fmov.l		%d1,%fp0		# convert to floating-format

	mov.l		%d1,L_SCR1(%a6)		# save N temporarily
	and.l		&0x3F,%d1		# D0 is J = N mod 64
	lsl.l		&4,%d1
	add.l		%d1,%a1			# address of 2^(J/64)
	mov.l		L_SCR1(%a6),%d1
	asr.l		&6,%d1			# D0 is M
	mov.l		%d1,L_SCR1(%a6)		# save a copy of M

#--Step 3.
#--fp1,fp2 saved on the stack. fp0 is N, fp1 is X,
#--a0 points to 2^(J/64), D0 and a1 both contain M
	fmov.x		%fp0,%fp2
	fmul.s		&0xBC317218,%fp0	# N * L1, L1 = lead(-log2/64)
	fmul.x		L2(%pc),%fp2		# N * L2, L1+L2 = -log2/64
	fadd.x		%fp1,%fp0		# X + N*L1
	fadd.x		%fp2,%fp0		# fp0 is R, reduced arg.
	add.w		&0x3FFF,%d1		# D0 is biased expo. of 2^M

#--Step 4.
#--WE NOW COMPUTE EXP(R)-1 BY A POLYNOMIAL
#-- R + R*R*(A1 + R*(A2 + R*(A3 + R*(A4 + R*(A5 + R*A6)))))
#--TO FULLY UTILIZE THE PIPELINE, WE COMPUTE S = R*R
#--[R*S*(A2+S*(A4+S*A6))] + [R+S*(A1+S*(A3+S*A5))]

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# fp1 IS S = R*R

	fmov.s		&0x3950097B,%fp2	# fp2 IS a6

	fmul.x		%fp1,%fp2		# fp2 IS S*A6
	fmov.x		%fp1,%fp3
	fmul.s		&0x3AB60B6A,%fp3	# fp3 IS S*A5

	fadd.d		EM1A4(%pc),%fp2		# fp2 IS A4+S*A6
	fadd.d		EM1A3(%pc),%fp3		# fp3 IS A3+S*A5
	mov.w		%d1,SC(%a6)		# SC is 2^(M) in extended
	mov.l		&0x80000000,SC+4(%a6)
	clr.l		SC+8(%a6)

	fmul.x		%fp1,%fp2		# fp2 IS S*(A4+S*A6)
	mov.l		L_SCR1(%a6),%d1		# D0 is	M
	neg.w		%d1			# D0 is -M
	fmul.x		%fp1,%fp3		# fp3 IS S*(A3+S*A5)
	add.w		&0x3FFF,%d1		# biased expo. of 2^(-M)
	fadd.d		EM1A2(%pc),%fp2		# fp2 IS A2+S*(A4+S*A6)
	fadd.s		&0x3F000000,%fp3	# fp3 IS A1+S*(A3+S*A5)

	fmul.x		%fp1,%fp2		# fp2 IS S*(A2+S*(A4+S*A6))
	or.w		&0x8000,%d1		# signed/expo. of -2^(-M)
	mov.w		%d1,ONEBYSC(%a6)	# OnebySc is -2^(-M)
	mov.l		&0x80000000,ONEBYSC+4(%a6)
	clr.l		ONEBYSC+8(%a6)
	fmul.x		%fp3,%fp1		# fp1 IS S*(A1+S*(A3+S*A5))

	fmul.x		%fp0,%fp2		# fp2 IS R*S*(A2+S*(A4+S*A6))
	fadd.x		%fp1,%fp0		# fp0 IS R+S*(A1+S*(A3+S*A5))

	fadd.x		%fp2,%fp0		# fp0 IS EXP(R)-1

	fmovm.x		(%sp)+,&0x30		# fp2 restored {%fp2/%fp3}

#--Step 5
#--Compute 2^(J/64)*p

	fmul.x		(%a1),%fp0		# 2^(J/64)*(Exp(R)-1)

#--Step 6
#--Step 6.1
	mov.l		L_SCR1(%a6),%d1		# retrieve M
	cmp.l		%d1,&63
	ble.b		MLE63
#--Step 6.2	M >= 64
	fmov.s		12(%a1),%fp1		# fp1 is t
	fadd.x		ONEBYSC(%a6),%fp1	# fp1 is t+OnebySc
	fadd.x		%fp1,%fp0		# p+(t+OnebySc), fp1 released
	fadd.x		(%a1),%fp0		# T+(p+(t+OnebySc))
	bra		EM1SCALE
MLE63:
#--Step 6.3	M <= 63
	cmp.l		%d1,&-3
	bge.b		MGEN3
MLTN3:
#--Step 6.4	M <= -4
	fadd.s		12(%a1),%fp0		# p+t
	fadd.x		(%a1),%fp0		# T+(p+t)
	fadd.x		ONEBYSC(%a6),%fp0	# OnebySc + (T+(p+t))
	bra		EM1SCALE
MGEN3:
#--Step 6.5	-3 <= M <= 63
	fmov.x		(%a1)+,%fp1		# fp1 is T
	fadd.s		(%a1),%fp0		# fp0 is p+t
	fadd.x		ONEBYSC(%a6),%fp1	# fp1 is T+OnebySc
	fadd.x		%fp1,%fp0		# (T+OnebySc)+(p+t)

EM1SCALE:
#--Step 6.6
	fmov.l		%d0,%fpcr
	fmul.x		SC(%a6),%fp0
	bra		t_inx2

EM1SM:
#--Step 7	|X| < 1/4.
	cmp.l		%d1,&0x3FBE0000		# 2^(-65)
	bge.b		EM1POLY

EM1TINY:
#--Step 8	|X| < 2^(-65)
	cmp.l		%d1,&0x00330000		# 2^(-16312)
	blt.b		EM12TINY
#--Step 8.2
	mov.l		&0x80010000,SC(%a6)	# SC is -2^(-16382)
	mov.l		&0x80000000,SC+4(%a6)
	clr.l		SC+8(%a6)
	fmov.x		(%a0),%fp0
	fmov.l		%d0,%fpcr
	mov.b		&FADD_OP,%d1		# last inst is ADD
	fadd.x		SC(%a6),%fp0
	bra		t_catch

EM12TINY:
#--Step 8.3
	fmov.x		(%a0),%fp0
	fmul.d		TWO140(%pc),%fp0
	mov.l		&0x80010000,SC(%a6)
	mov.l		&0x80000000,SC+4(%a6)
	clr.l		SC+8(%a6)
	fadd.x		SC(%a6),%fp0
	fmov.l		%d0,%fpcr
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.d		TWON140(%pc),%fp0
	bra		t_catch

EM1POLY:
#--Step 9	exp(X)-1 by a simple polynomial
	fmov.x		(%a0),%fp0		# fp0 is X
	fmul.x		%fp0,%fp0		# fp0 is S := X*X
	fmovm.x		&0xc,-(%sp)		# save fp2 {%fp2/%fp3}
	fmov.s		&0x2F30CAA8,%fp1	# fp1 is B12
	fmul.x		%fp0,%fp1		# fp1 is S*B12
	fmov.s		&0x310F8290,%fp2	# fp2 is B11
	fadd.s		&0x32D73220,%fp1	# fp1 is B10+S*B12

	fmul.x		%fp0,%fp2		# fp2 is S*B11
	fmul.x		%fp0,%fp1		# fp1 is S*(B10 + ...

	fadd.s		&0x3493F281,%fp2	# fp2 is B9+S*...
	fadd.d		EM1B8(%pc),%fp1		# fp1 is B8+S*...

	fmul.x		%fp0,%fp2		# fp2 is S*(B9+...
	fmul.x		%fp0,%fp1		# fp1 is S*(B8+...

	fadd.d		EM1B7(%pc),%fp2		# fp2 is B7+S*...
	fadd.d		EM1B6(%pc),%fp1		# fp1 is B6+S*...

	fmul.x		%fp0,%fp2		# fp2 is S*(B7+...
	fmul.x		%fp0,%fp1		# fp1 is S*(B6+...

	fadd.d		EM1B5(%pc),%fp2		# fp2 is B5+S*...
	fadd.d		EM1B4(%pc),%fp1		# fp1 is B4+S*...

	fmul.x		%fp0,%fp2		# fp2 is S*(B5+...
	fmul.x		%fp0,%fp1		# fp1 is S*(B4+...

	fadd.d		EM1B3(%pc),%fp2		# fp2 is B3+S*...
	fadd.x		EM1B2(%pc),%fp1		# fp1 is B2+S*...

	fmul.x		%fp0,%fp2		# fp2 is S*(B3+...
	fmul.x		%fp0,%fp1		# fp1 is S*(B2+...

	fmul.x		%fp0,%fp2		# fp2 is S*S*(B3+...)
	fmul.x		(%a0),%fp1		# fp1 is X*S*(B2...

	fmul.s		&0x3F000000,%fp0	# fp0 is S*B1
	fadd.x		%fp2,%fp1		# fp1 is Q

	fmovm.x		(%sp)+,&0x30		# fp2 restored {%fp2/%fp3}

	fadd.x		%fp1,%fp0		# fp0 is S*B1+Q

	fmov.l		%d0,%fpcr
	fadd.x		(%a0),%fp0
	bra		t_inx2

EM1BIG:
#--Step 10	|X| > 70 log2
	mov.l		(%a0),%d1
	cmp.l		%d1,&0
	bgt.w		EXPC1
#--Step 10.2
	fmov.s		&0xBF800000,%fp0	# fp0 is -1
	fmov.l		%d0,%fpcr
	fadd.s		&0x00800000,%fp0	# -1 + 2^(-126)
	bra		t_minx2

	global		setoxm1d
setoxm1d:
#--entry point for EXPM1(X), here X is denormalized
#--Step 0.
	bra		t_extdnrm

#########################################################################
# sgetexp():  returns the exponent portion of the input argument.	#
#	      The exponent bias is removed and the exponent value is	#
#	      returned as an extended precision number in fp0.		#
# sgetexpd(): handles denormalized numbers. 				#
#									#
# sgetman():  extracts the mantissa of the input argument. The 		#
#	      mantissa is converted to an extended precision number w/ 	#
#	      an exponent of $3fff and is returned in fp0. The range of #
#	      the result is [1.0 - 2.0).				#
# sgetmand(): handles denormalized numbers.				#
#									#
# INPUT *************************************************************** #
#	a0  = pointer to extended precision input			#
#									#
# OUTPUT ************************************************************** #
#	fp0 = exponent(X) or mantissa(X)				#
#									#
#########################################################################

	global		sgetexp
sgetexp:
	mov.w		SRC_EX(%a0),%d0		# get the exponent
	bclr		&0xf,%d0		# clear the sign bit
	subi.w		&0x3fff,%d0		# subtract off the bias
	fmov.w		%d0,%fp0		# return exp in fp0
	blt.b		sgetexpn		# it's negative
	rts

sgetexpn:
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
	rts

	global		sgetexpd
sgetexpd:
	bsr.l		norm			# normalize
	neg.w		%d0			# new exp = -(shft amt)
	subi.w		&0x3fff,%d0		# subtract off the bias
	fmov.w		%d0,%fp0		# return exp in fp0
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
	rts

	global		sgetman
sgetman:
	mov.w		SRC_EX(%a0),%d0		# get the exp
	ori.w		&0x7fff,%d0		# clear old exp
	bclr		&0xe,%d0		# make it the new exp +-3fff

# here, we build the result in a tmp location so as not to disturb the input
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6) # copy to tmp loc
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6) # copy to tmp loc
	mov.w		%d0,FP_SCR0_EX(%a6)	# insert new exponent
	fmov.x		FP_SCR0(%a6),%fp0	# put new value back in fp0
	bmi.b		sgetmann		# it's negative
	rts

sgetmann:
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
	rts

#
# For denormalized numbers, shift the mantissa until the j-bit = 1,
# then load the exponent with +/1 $3fff.
#
	global		sgetmand
sgetmand:
	bsr.l		norm			# normalize exponent
	bra.b		sgetman

#########################################################################
# scosh():  computes the hyperbolic cosine of a normalized input	#
# scoshd(): computes the hyperbolic cosine of a denormalized input	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT **************************************************************	#
#	fp0 = cosh(X)							#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 3 ulps in 64 significant bit, 	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic 	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#									#
#	COSH								#
#	1. If |X| > 16380 log2, go to 3.				#
#									#
#	2. (|X| <= 16380 log2) Cosh(X) is obtained by the formulae	#
#		y = |X|, z = exp(Y), and				#
#		cosh(X) = (1/2)*( z + 1/z ).				#
#		Exit.							#
#									#
#	3. (|X| > 16380 log2). If |X| > 16480 log2, go to 5.		#
#									#
#	4. (16380 log2 < |X| <= 16480 log2)				#
#		cosh(X) = sign(X) * exp(|X|)/2.				#
#		However, invoking exp(|X|) may cause premature 		#
#		overflow. Thus, we calculate sinh(X) as follows:	#
#		Y	:= |X|						#
#		Fact	:=	2**(16380)				#
#		Y'	:= Y - 16381 log2				#
#		cosh(X) := Fact * exp(Y').				#
#		Exit.							#
#									#
#	5. (|X| > 16480 log2) sinh(X) must overflow. Return		#
#		Huge*Huge to generate overflow and an infinity with	#
#		the appropriate sign. Huge is the largest finite number	#
#		in extended format. Exit.				#
#									#
#########################################################################

TWO16380:
	long		0x7FFB0000,0x80000000,0x00000000,0x00000000

	global		scosh
scosh:
	fmov.x		(%a0),%fp0		# LOAD INPUT

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	and.l		&0x7FFFFFFF,%d1
	cmp.l		%d1,&0x400CB167
	bgt.b		COSHBIG

#--THIS IS THE USUAL CASE, |X| < 16380 LOG2
#--COSH(X) = (1/2) * ( EXP(X) + 1/EXP(X) )

	fabs.x		%fp0			# |X|

	mov.l		%d0,-(%sp)
	clr.l		%d0
	fmovm.x		&0x01,-(%sp)		# save |X| to stack
	lea		(%sp),%a0		# pass ptr to |X|
	bsr		setox			# FP0 IS EXP(|X|)
	add.l		&0xc,%sp		# erase |X| from stack
	fmul.s		&0x3F000000,%fp0	# (1/2)EXP(|X|)
	mov.l		(%sp)+,%d0

	fmov.s		&0x3E800000,%fp1	# (1/4)
	fdiv.x		%fp0,%fp1		# 1/(2 EXP(|X|))

	fmov.l		%d0,%fpcr
	mov.b		&FADD_OP,%d1		# last inst is ADD
	fadd.x		%fp1,%fp0
	bra		t_catch

COSHBIG:
	cmp.l		%d1,&0x400CB2B3
	bgt.b		COSHHUGE

	fabs.x		%fp0
	fsub.d		T1(%pc),%fp0		# (|X|-16381LOG2_LEAD)
	fsub.d		T2(%pc),%fp0		# |X| - 16381 LOG2, ACCURATE

	mov.l		%d0,-(%sp)
	clr.l		%d0
	fmovm.x		&0x01,-(%sp)		# save fp0 to stack
	lea		(%sp),%a0		# pass ptr to fp0
	bsr		setox
	add.l		&0xc,%sp		# clear fp0 from stack
	mov.l		(%sp)+,%d0

	fmov.l		%d0,%fpcr
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.x		TWO16380(%pc),%fp0
	bra		t_catch

COSHHUGE:
	bra		t_ovfl2

	global		scoshd
#--COSH(X) = 1 FOR DENORMALIZED X
scoshd:
	fmov.s		&0x3F800000,%fp0

	fmov.l		%d0,%fpcr
	fadd.s		&0x00800000,%fp0
	bra		t_pinx2

#########################################################################
# ssinh():  computes the hyperbolic sine of a normalized input		#
# ssinhd(): computes the hyperbolic sine of a denormalized input	#
#									#
# INPUT *************************************************************** #
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT ************************************************************** #
#	fp0 = sinh(X)							#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 3 ulps in 64 significant bit, 	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently #
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM *********************************************************** #
#									#
#       SINH								#
#       1. If |X| > 16380 log2, go to 3.				#
#									#
#       2. (|X| <= 16380 log2) Sinh(X) is obtained by the formula	#
#               y = |X|, sgn = sign(X), and z = expm1(Y),		#
#               sinh(X) = sgn*(1/2)*( z + z/(1+z) ).			#
#          Exit.							#
#									#
#       3. If |X| > 16480 log2, go to 5.				#
#									#
#       4. (16380 log2 < |X| <= 16480 log2)				#
#               sinh(X) = sign(X) * exp(|X|)/2.				#
#          However, invoking exp(|X|) may cause premature overflow.	#
#          Thus, we calculate sinh(X) as follows:			#
#             Y       := |X|						#
#             sgn     := sign(X)					#
#             sgnFact := sgn * 2**(16380)				#
#             Y'      := Y - 16381 log2					#
#             sinh(X) := sgnFact * exp(Y').				#
#          Exit.							#
#									#
#       5. (|X| > 16480 log2) sinh(X) must overflow. Return		#
#          sign(X)*Huge*Huge to generate overflow and an infinity with	#
#          the appropriate sign. Huge is the largest finite number in	#
#          extended format. Exit.					#
#									#
#########################################################################

	global		ssinh
ssinh:
	fmov.x		(%a0),%fp0		# LOAD INPUT

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	mov.l		%d1,%a1			# save (compacted) operand
	and.l		&0x7FFFFFFF,%d1
	cmp.l		%d1,&0x400CB167
	bgt.b		SINHBIG

#--THIS IS THE USUAL CASE, |X| < 16380 LOG2
#--Y = |X|, Z = EXPM1(Y), SINH(X) = SIGN(X)*(1/2)*( Z + Z/(1+Z) )

	fabs.x		%fp0			# Y = |X|

	movm.l		&0x8040,-(%sp)		# {a1/d0}
	fmovm.x		&0x01,-(%sp)		# save Y on stack
	lea		(%sp),%a0		# pass ptr to Y
	clr.l		%d0
	bsr		setoxm1			# FP0 IS Z = EXPM1(Y)
	add.l		&0xc,%sp		# clear Y from stack
	fmov.l		&0,%fpcr
	movm.l		(%sp)+,&0x0201		# {a1/d0}

	fmov.x		%fp0,%fp1
	fadd.s		&0x3F800000,%fp1	# 1+Z
	fmov.x		%fp0,-(%sp)
	fdiv.x		%fp1,%fp0		# Z/(1+Z)
	mov.l		%a1,%d1
	and.l		&0x80000000,%d1
	or.l		&0x3F000000,%d1
	fadd.x		(%sp)+,%fp0
	mov.l		%d1,-(%sp)

	fmov.l		%d0,%fpcr
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.s		(%sp)+,%fp0		# last fp inst - possible exceptions set
	bra		t_catch

SINHBIG:
	cmp.l		%d1,&0x400CB2B3
	bgt		t_ovfl
	fabs.x		%fp0
	fsub.d		T1(%pc),%fp0		# (|X|-16381LOG2_LEAD)
	mov.l		&0,-(%sp)
	mov.l		&0x80000000,-(%sp)
	mov.l		%a1,%d1
	and.l		&0x80000000,%d1
	or.l		&0x7FFB0000,%d1
	mov.l		%d1,-(%sp)		# EXTENDED FMT
	fsub.d		T2(%pc),%fp0		# |X| - 16381 LOG2, ACCURATE

	mov.l		%d0,-(%sp)
	clr.l		%d0
	fmovm.x		&0x01,-(%sp)		# save fp0 on stack
	lea		(%sp),%a0		# pass ptr to fp0
	bsr		setox
	add.l		&0xc,%sp		# clear fp0 from stack

	mov.l		(%sp)+,%d0
	fmov.l		%d0,%fpcr
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.x		(%sp)+,%fp0		# possible exception
	bra		t_catch

	global		ssinhd
#--SINH(X) = X FOR DENORMALIZED X
ssinhd:
	bra		t_extdnrm

#########################################################################
# stanh():  computes the hyperbolic tangent of a normalized input	#
# stanhd(): computes the hyperbolic tangent of a denormalized input	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT **************************************************************	#
#	fp0 = tanh(X)							#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 3 ulps in 64 significant bit, 	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently #
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#									#
#	TANH								#
#	1. If |X| >= (5/2) log2 or |X| <= 2**(-40), go to 3.		#
#									#
#	2. (2**(-40) < |X| < (5/2) log2) Calculate tanh(X) by		#
#		sgn := sign(X), y := 2|X|, z := expm1(Y), and		#
#		tanh(X) = sgn*( z/(2+z) ).				#
#		Exit.							#
#									#
#	3. (|X| <= 2**(-40) or |X| >= (5/2) log2). If |X| < 1,		#
#		go to 7.						#
#									#
#	4. (|X| >= (5/2) log2) If |X| >= 50 log2, go to 6.		#
#									#
#	5. ((5/2) log2 <= |X| < 50 log2) Calculate tanh(X) by		#
#		sgn := sign(X), y := 2|X|, z := exp(Y),			#
#		tanh(X) = sgn - [ sgn*2/(1+z) ].			#
#		Exit.							#
#									#
#	6. (|X| >= 50 log2) Tanh(X) = +-1 (round to nearest). Thus, we	#
#		calculate Tanh(X) by					#
#		sgn := sign(X), Tiny := 2**(-126),			#
#		tanh(X) := sgn - sgn*Tiny.				#
#		Exit.							#
#									#
#	7. (|X| < 2**(-40)). Tanh(X) = X.	Exit.			#
#									#
#########################################################################

	set		X,FP_SCR0
	set		XFRAC,X+4

	set		SGN,L_SCR3

	set		V,FP_SCR0

	global		stanh
stanh:
	fmov.x		(%a0),%fp0		# LOAD INPUT

	fmov.x		%fp0,X(%a6)
	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	mov.l		%d1,X(%a6)
	and.l		&0x7FFFFFFF,%d1
	cmp.l		%d1, &0x3fd78000	# is |X| < 2^(-40)?
	blt.w		TANHBORS		# yes
	cmp.l		%d1, &0x3fffddce	# is |X| > (5/2)LOG2?
	bgt.w		TANHBORS		# yes

#--THIS IS THE USUAL CASE
#--Y = 2|X|, Z = EXPM1(Y), TANH(X) = SIGN(X) * Z / (Z+2).

	mov.l		X(%a6),%d1
	mov.l		%d1,SGN(%a6)
	and.l		&0x7FFF0000,%d1
	add.l		&0x00010000,%d1		# EXPONENT OF 2|X|
	mov.l		%d1,X(%a6)
	and.l		&0x80000000,SGN(%a6)
	fmov.x		X(%a6),%fp0		# FP0 IS Y = 2|X|

	mov.l		%d0,-(%sp)
	clr.l		%d0
	fmovm.x		&0x1,-(%sp)		# save Y on stack
	lea		(%sp),%a0		# pass ptr to Y
	bsr		setoxm1			# FP0 IS Z = EXPM1(Y)
	add.l		&0xc,%sp		# clear Y from stack
	mov.l		(%sp)+,%d0

	fmov.x		%fp0,%fp1
	fadd.s		&0x40000000,%fp1	# Z+2
	mov.l		SGN(%a6),%d1
	fmov.x		%fp1,V(%a6)
	eor.l		%d1,V(%a6)

	fmov.l		%d0,%fpcr		# restore users round prec,mode
	fdiv.x		V(%a6),%fp0
	bra		t_inx2

TANHBORS:
	cmp.l		%d1,&0x3FFF8000
	blt.w		TANHSM

	cmp.l		%d1,&0x40048AA1
	bgt.w		TANHHUGE

#-- (5/2) LOG2 < |X| < 50 LOG2,
#--TANH(X) = 1 - (2/[EXP(2X)+1]). LET Y = 2|X|, SGN = SIGN(X),
#--TANH(X) = SGN -	SGN*2/[EXP(Y)+1].

	mov.l		X(%a6),%d1
	mov.l		%d1,SGN(%a6)
	and.l		&0x7FFF0000,%d1
	add.l		&0x00010000,%d1		# EXPO OF 2|X|
	mov.l		%d1,X(%a6)		# Y = 2|X|
	and.l		&0x80000000,SGN(%a6)
	mov.l		SGN(%a6),%d1
	fmov.x		X(%a6),%fp0		# Y = 2|X|

	mov.l		%d0,-(%sp)
	clr.l		%d0
	fmovm.x		&0x01,-(%sp)		# save Y on stack
	lea		(%sp),%a0		# pass ptr to Y
	bsr		setox			# FP0 IS EXP(Y)
	add.l		&0xc,%sp		# clear Y from stack
	mov.l		(%sp)+,%d0
	mov.l		SGN(%a6),%d1
	fadd.s		&0x3F800000,%fp0	# EXP(Y)+1

	eor.l		&0xC0000000,%d1		# -SIGN(X)*2
	fmov.s		%d1,%fp1		# -SIGN(X)*2 IN SGL FMT
	fdiv.x		%fp0,%fp1		# -SIGN(X)2 / [EXP(Y)+1 ]

	mov.l		SGN(%a6),%d1
	or.l		&0x3F800000,%d1		# SGN
	fmov.s		%d1,%fp0		# SGN IN SGL FMT

	fmov.l		%d0,%fpcr		# restore users round prec,mode
	mov.b		&FADD_OP,%d1		# last inst is ADD
	fadd.x		%fp1,%fp0
	bra		t_inx2

TANHSM:
	fmov.l		%d0,%fpcr		# restore users round prec,mode
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		X(%a6),%fp0		# last inst - possible exception set
	bra		t_catch

#---RETURN SGN(X) - SGN(X)EPS
TANHHUGE:
	mov.l		X(%a6),%d1
	and.l		&0x80000000,%d1
	or.l		&0x3F800000,%d1
	fmov.s		%d1,%fp0
	and.l		&0x80000000,%d1
	eor.l		&0x80800000,%d1		# -SIGN(X)*EPS

	fmov.l		%d0,%fpcr		# restore users round prec,mode
	fadd.s		%d1,%fp0
	bra		t_inx2

	global		stanhd
#--TANH(X) = X FOR DENORMALIZED X
stanhd:
	bra		t_extdnrm

#########################################################################
# slogn():    computes the natural logarithm of a normalized input	#
# slognd():   computes the natural logarithm of a denormalized input	#
# slognp1():  computes the log(1+X) of a normalized input		#
# slognp1d(): computes the log(1+X) of a denormalized input		#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT **************************************************************	#
#	fp0 = log(X) or log(1+X)					#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 2 ulps in 64 significant bit, 	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#	LOGN:								#
#	Step 1. If |X-1| < 1/16, approximate log(X) by an odd 		#
#		polynomial in u, where u = 2(X-1)/(X+1). Otherwise, 	#
#		move on to Step 2.					#
#									#
#	Step 2. X = 2**k * Y where 1 <= Y < 2. Define F to be the first	#
#		seven significant bits of Y plus 2**(-7), i.e. 		#
#		F = 1.xxxxxx1 in base 2 where the six "x" match those 	#
#		of Y. Note that |Y-F| <= 2**(-7).			#
#									#
#	Step 3. Define u = (Y-F)/F. Approximate log(1+u) by a 		#
#		polynomial in u, log(1+u) = poly.			#
#									#
#	Step 4. Reconstruct 						#
#		log(X) = log( 2**k * Y ) = k*log(2) + log(F) + log(1+u)	#
#		by k*log(2) + (log(F) + poly). The values of log(F) are	#
#		calculated beforehand and stored in the program.	#
#									#
#	lognp1:								#
#	Step 1: If |X| < 1/16, approximate log(1+X) by an odd 		#
#		polynomial in u where u = 2X/(2+X). Otherwise, move on	#
#		to Step 2.						#
#									#
#	Step 2: Let 1+X = 2**k * Y, where 1 <= Y < 2. Define F as done	#
#		in Step 2 of the algorithm for LOGN and compute 	#
#		log(1+X) as k*log(2) + log(F) + poly where poly 	#
#		approximates log(1+u), u = (Y-F)/F. 			#
#									#
#	Implementation Notes:						#
#	Note 1. There are 64 different possible values for F, thus 64 	#
#		log(F)'s need to be tabulated. Moreover, the values of	#
#		1/F are also tabulated so that the division in (Y-F)/F	#
#		can be performed by a multiplication.			#
#									#
#	Note 2. In Step 2 of lognp1, in order to preserved accuracy, 	#
#		the value Y-F has to be calculated carefully when 	#
#		1/2 <= X < 3/2. 					#
#									#
#	Note 3. To fully exploit the pipeline, polynomials are usually 	#
#		separated into two parts evaluated independently before	#
#		being added up.						#
#									#
#########################################################################
LOGOF2:
	long		0x3FFE0000,0xB17217F7,0xD1CF79AC,0x00000000

one:
	long		0x3F800000
zero:
	long		0x00000000
infty:
	long		0x7F800000
negone:
	long		0xBF800000

LOGA6:
	long		0x3FC2499A,0xB5E4040B
LOGA5:
	long		0xBFC555B5,0x848CB7DB

LOGA4:
	long		0x3FC99999,0x987D8730
LOGA3:
	long		0xBFCFFFFF,0xFF6F7E97

LOGA2:
	long		0x3FD55555,0x555555A4
LOGA1:
	long		0xBFE00000,0x00000008

LOGB5:
	long		0x3F175496,0xADD7DAD6
LOGB4:
	long		0x3F3C71C2,0xFE80C7E0

LOGB3:
	long		0x3F624924,0x928BCCFF
LOGB2:
	long		0x3F899999,0x999995EC

LOGB1:
	long		0x3FB55555,0x55555555
TWO:
	long		0x40000000,0x00000000

LTHOLD:
	long		0x3f990000,0x80000000,0x00000000,0x00000000

LOGTBL:
	long		0x3FFE0000,0xFE03F80F,0xE03F80FE,0x00000000
	long		0x3FF70000,0xFF015358,0x833C47E2,0x00000000
	long		0x3FFE0000,0xFA232CF2,0x52138AC0,0x00000000
	long		0x3FF90000,0xBDC8D83E,0xAD88D549,0x00000000
	long		0x3FFE0000,0xF6603D98,0x0F6603DA,0x00000000
	long		0x3FFA0000,0x9CF43DCF,0xF5EAFD48,0x00000000
	long		0x3FFE0000,0xF2B9D648,0x0F2B9D65,0x00000000
	long		0x3FFA0000,0xDA16EB88,0xCB8DF614,0x00000000
	long		0x3FFE0000,0xEF2EB71F,0xC4345238,0x00000000
	long		0x3FFB0000,0x8B29B775,0x1BD70743,0x00000000
	long		0x3FFE0000,0xEBBDB2A5,0xC1619C8C,0x00000000
	long		0x3FFB0000,0xA8D839F8,0x30C1FB49,0x00000000
	long		0x3FFE0000,0xE865AC7B,0x7603A197,0x00000000
	long		0x3FFB0000,0xC61A2EB1,0x8CD907AD,0x00000000
	long		0x3FFE0000,0xE525982A,0xF70C880E,0x00000000
	long		0x3FFB0000,0xE2F2A47A,0xDE3A18AF,0x00000000
	long		0x3FFE0000,0xE1FC780E,0x1FC780E2,0x00000000
	long		0x3FFB0000,0xFF64898E,0xDF55D551,0x00000000
	long		0x3FFE0000,0xDEE95C4C,0xA037BA57,0x00000000
	long		0x3FFC0000,0x8DB956A9,0x7B3D0148,0x00000000
	long		0x3FFE0000,0xDBEB61EE,0xD19C5958,0x00000000
	long		0x3FFC0000,0x9B8FE100,0xF47BA1DE,0x00000000
	long		0x3FFE0000,0xD901B203,0x6406C80E,0x00000000
	long		0x3FFC0000,0xA9372F1D,0x0DA1BD17,0x00000000
	long		0x3FFE0000,0xD62B80D6,0x2B80D62C,0x00000000
	long		0x3FFC0000,0xB6B07F38,0xCE90E46B,0x00000000
	long		0x3FFE0000,0xD3680D36,0x80D3680D,0x00000000
	long		0x3FFC0000,0xC3FD0329,0x06488481,0x00000000
	long		0x3FFE0000,0xD0B69FCB,0xD2580D0B,0x00000000
	long		0x3FFC0000,0xD11DE0FF,0x15AB18CA,0x00000000
	long		0x3FFE0000,0xCE168A77,0x25080CE1,0x00000000
	long		0x3FFC0000,0xDE1433A1,0x6C66B150,0x00000000
	long		0x3FFE0000,0xCB8727C0,0x65C393E0,0x00000000
	long		0x3FFC0000,0xEAE10B5A,0x7DDC8ADD,0x00000000
	long		0x3FFE0000,0xC907DA4E,0x871146AD,0x00000000
	long		0x3FFC0000,0xF7856E5E,0xE2C9B291,0x00000000
	long		0x3FFE0000,0xC6980C69,0x80C6980C,0x00000000
	long		0x3FFD0000,0x82012CA5,0xA68206D7,0x00000000
	long		0x3FFE0000,0xC4372F85,0x5D824CA6,0x00000000
	long		0x3FFD0000,0x882C5FCD,0x7256A8C5,0x00000000
	long		0x3FFE0000,0xC1E4BBD5,0x95F6E947,0x00000000
	long		0x3FFD0000,0x8E44C60B,0x4CCFD7DE,0x00000000
	long		0x3FFE0000,0xBFA02FE8,0x0BFA02FF,0x00000000
	long		0x3FFD0000,0x944AD09E,0xF4351AF6,0x00000000
	long		0x3FFE0000,0xBD691047,0x07661AA3,0x00000000
	long		0x3FFD0000,0x9A3EECD4,0xC3EAA6B2,0x00000000
	long		0x3FFE0000,0xBB3EE721,0xA54D880C,0x00000000
	long		0x3FFD0000,0xA0218434,0x353F1DE8,0x00000000
	long		0x3FFE0000,0xB92143FA,0x36F5E02E,0x00000000
	long		0x3FFD0000,0xA5F2FCAB,0xBBC506DA,0x00000000
	long		0x3FFE0000,0xB70FBB5A,0x19BE3659,0x00000000
	long		0x3FFD0000,0xABB3B8BA,0x2AD362A5,0x00000000
	long		0x3FFE0000,0xB509E68A,0x9B94821F,0x00000000
	long		0x3FFD0000,0xB1641795,0xCE3CA97B,0x00000000
	long		0x3FFE0000,0xB30F6352,0x8917C80B,0x00000000
	long		0x3FFD0000,0xB7047551,0x5D0F1C61,0x00000000
	long		0x3FFE0000,0xB11FD3B8,0x0B11FD3C,0x00000000
	long		0x3FFD0000,0xBC952AFE,0xEA3D13E1,0x00000000
	long		0x3FFE0000,0xAF3ADDC6,0x80AF3ADE,0x00000000
	long		0x3FFD0000,0xC2168ED0,0xF458BA4A,0x00000000
	long		0x3FFE0000,0xAD602B58,0x0AD602B6,0x00000000
	long		0x3FFD0000,0xC788F439,0xB3163BF1,0x00000000
	long		0x3FFE0000,0xAB8F69E2,0x8359CD11,0x00000000
	long		0x3FFD0000,0xCCECAC08,0xBF04565D,0x00000000
	long		0x3FFE0000,0xA9C84A47,0xA07F5638,0x00000000
	long		0x3FFD0000,0xD2420487,0x2DD85160,0x00000000
	long		0x3FFE0000,0xA80A80A8,0x0A80A80B,0x00000000
	long		0x3FFD0000,0xD7894992,0x3BC3588A,0x00000000
	long		0x3FFE0000,0xA655C439,0x2D7B73A8,0x00000000
	long		0x3FFD0000,0xDCC2C4B4,0x9887DACC,0x00000000
	long		0x3FFE0000,0xA4A9CF1D,0x96833751,0x00000000
	long		0x3FFD0000,0xE1EEBD3E,0x6D6A6B9E,0x00000000
	long		0x3FFE0000,0xA3065E3F,0xAE7CD0E0,0x00000000
	long		0x3FFD0000,0xE70D785C,0x2F9F5BDC,0x00000000
	long		0x3FFE0000,0xA16B312E,0xA8FC377D,0x00000000
	long		0x3FFD0000,0xEC1F392C,0x5179F283,0x00000000
	long		0x3FFE0000,0x9FD809FD,0x809FD80A,0x00000000
	long		0x3FFD0000,0xF12440D3,0xE36130E6,0x00000000
	long		0x3FFE0000,0x9E4CAD23,0xDD5F3A20,0x00000000
	long		0x3FFD0000,0xF61CCE92,0x346600BB,0x00000000
	long		0x3FFE0000,0x9CC8E160,0xC3FB19B9,0x00000000
	long		0x3FFD0000,0xFB091FD3,0x8145630A,0x00000000
	long		0x3FFE0000,0x9B4C6F9E,0xF03A3CAA,0x00000000
	long		0x3FFD0000,0xFFE97042,0xBFA4C2AD,0x00000000
	long		0x3FFE0000,0x99D722DA,0xBDE58F06,0x00000000
	long		0x3FFE0000,0x825EFCED,0x49369330,0x00000000
	long		0x3FFE0000,0x9868C809,0x868C8098,0x00000000
	long		0x3FFE0000,0x84C37A7A,0xB9A905C9,0x00000000
	long		0x3FFE0000,0x97012E02,0x5C04B809,0x00000000
	long		0x3FFE0000,0x87224C2E,0x8E645FB7,0x00000000
	long		0x3FFE0000,0x95A02568,0x095A0257,0x00000000
	long		0x3FFE0000,0x897B8CAC,0x9F7DE298,0x00000000
	long		0x3FFE0000,0x94458094,0x45809446,0x00000000
	long		0x3FFE0000,0x8BCF55DE,0xC4CD05FE,0x00000000
	long		0x3FFE0000,0x92F11384,0x0497889C,0x00000000
	long		0x3FFE0000,0x8E1DC0FB,0x89E125E5,0x00000000
	long		0x3FFE0000,0x91A2B3C4,0xD5E6F809,0x00000000
	long		0x3FFE0000,0x9066E68C,0x955B6C9B,0x00000000
	long		0x3FFE0000,0x905A3863,0x3E06C43B,0x00000000
	long		0x3FFE0000,0x92AADE74,0xC7BE59E0,0x00000000
	long		0x3FFE0000,0x8F1779D9,0xFDC3A219,0x00000000
	long		0x3FFE0000,0x94E9BFF6,0x15845643,0x00000000
	long		0x3FFE0000,0x8DDA5202,0x37694809,0x00000000
	long		0x3FFE0000,0x9723A1B7,0x20134203,0x00000000
	long		0x3FFE0000,0x8CA29C04,0x6514E023,0x00000000
	long		0x3FFE0000,0x995899C8,0x90EB8990,0x00000000
	long		0x3FFE0000,0x8B70344A,0x139BC75A,0x00000000
	long		0x3FFE0000,0x9B88BDAA,0x3A3DAE2F,0x00000000
	long		0x3FFE0000,0x8A42F870,0x5669DB46,0x00000000
	long		0x3FFE0000,0x9DB4224F,0xFFE1157C,0x00000000
	long		0x3FFE0000,0x891AC73A,0xE9819B50,0x00000000
	long		0x3FFE0000,0x9FDADC26,0x8B7A12DA,0x00000000
	long		0x3FFE0000,0x87F78087,0xF78087F8,0x00000000
	long		0x3FFE0000,0xA1FCFF17,0xCE733BD4,0x00000000
	long		0x3FFE0000,0x86D90544,0x7A34ACC6,0x00000000
	long		0x3FFE0000,0xA41A9E8F,0x5446FB9F,0x00000000
	long		0x3FFE0000,0x85BF3761,0x2CEE3C9B,0x00000000
	long		0x3FFE0000,0xA633CD7E,0x6771CD8B,0x00000000
	long		0x3FFE0000,0x84A9F9C8,0x084A9F9D,0x00000000
	long		0x3FFE0000,0xA8489E60,0x0B435A5E,0x00000000
	long		0x3FFE0000,0x83993052,0x3FBE3368,0x00000000
	long		0x3FFE0000,0xAA59233C,0xCCA4BD49,0x00000000
	long		0x3FFE0000,0x828CBFBE,0xB9A020A3,0x00000000
	long		0x3FFE0000,0xAC656DAE,0x6BCC4985,0x00000000
	long		0x3FFE0000,0x81848DA8,0xFAF0D277,0x00000000
	long		0x3FFE0000,0xAE6D8EE3,0x60BB2468,0x00000000
	long		0x3FFE0000,0x80808080,0x80808081,0x00000000
	long		0x3FFE0000,0xB07197A2,0x3C46C654,0x00000000

	set		ADJK,L_SCR1

	set		X,FP_SCR0
	set		XDCARE,X+2
	set		XFRAC,X+4

	set		F,FP_SCR1
	set		FFRAC,F+4

	set		KLOG2,FP_SCR0

	set		SAVEU,FP_SCR0

	global		slogn
#--ENTRY POINT FOR LOG(X) FOR X FINITE, NON-ZERO, NOT NAN'S
slogn:
	fmov.x		(%a0),%fp0		# LOAD INPUT
	mov.l		&0x00000000,ADJK(%a6)

LOGBGN:
#--FPCR SAVED AND CLEARED, INPUT IS 2^(ADJK)*FP0, FP0 CONTAINS
#--A FINITE, NON-ZERO, NORMALIZED NUMBER.

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1

	mov.l		(%a0),X(%a6)
	mov.l		4(%a0),X+4(%a6)
	mov.l		8(%a0),X+8(%a6)

	cmp.l		%d1,&0			# CHECK IF X IS NEGATIVE
	blt.w		LOGNEG			# LOG OF NEGATIVE ARGUMENT IS INVALID
# X IS POSITIVE, CHECK IF X IS NEAR 1
	cmp.l		%d1,&0x3ffef07d 	# IS X < 15/16?
	blt.b		LOGMAIN			# YES
	cmp.l		%d1,&0x3fff8841 	# IS X > 17/16?
	ble.w		LOGNEAR1		# NO

LOGMAIN:
#--THIS SHOULD BE THE USUAL CASE, X NOT VERY CLOSE TO 1

#--X = 2^(K) * Y, 1 <= Y < 2. THUS, Y = 1.XXXXXXXX....XX IN BINARY.
#--WE DEFINE F = 1.XXXXXX1, I.E. FIRST 7 BITS OF Y AND ATTACH A 1.
#--THE IDEA IS THAT LOG(X) = K*LOG2 + LOG(Y)
#--			 = K*LOG2 + LOG(F) + LOG(1 + (Y-F)/F).
#--NOTE THAT U = (Y-F)/F IS VERY SMALL AND THUS APPROXIMATING
#--LOG(1+U) CAN BE VERY EFFICIENT.
#--ALSO NOTE THAT THE VALUE 1/F IS STORED IN A TABLE SO THAT NO
#--DIVISION IS NEEDED TO CALCULATE (Y-F)/F. 

#--GET K, Y, F, AND ADDRESS OF 1/F.
	asr.l		&8,%d1
	asr.l		&8,%d1			# SHIFTED 16 BITS, BIASED EXPO. OF X
	sub.l		&0x3FFF,%d1		# THIS IS K
	add.l		ADJK(%a6),%d1		# ADJUST K, ORIGINAL INPUT MAY BE  DENORM.
	lea		LOGTBL(%pc),%a0		# BASE ADDRESS OF 1/F AND LOG(F)
	fmov.l		%d1,%fp1		# CONVERT K TO FLOATING-POINT FORMAT

#--WHILE THE CONVERSION IS GOING ON, WE GET F AND ADDRESS OF 1/F
	mov.l		&0x3FFF0000,X(%a6)	# X IS NOW Y, I.E. 2^(-K)*X
	mov.l		XFRAC(%a6),FFRAC(%a6)
	and.l		&0xFE000000,FFRAC(%a6)	# FIRST 7 BITS OF Y
	or.l		&0x01000000,FFRAC(%a6)	# GET F: ATTACH A 1 AT THE EIGHTH BIT
	mov.l		FFRAC(%a6),%d1	# READY TO GET ADDRESS OF 1/F
	and.l		&0x7E000000,%d1
	asr.l		&8,%d1
	asr.l		&8,%d1
	asr.l		&4,%d1			# SHIFTED 20, D0 IS THE DISPLACEMENT
	add.l		%d1,%a0			# A0 IS THE ADDRESS FOR 1/F

	fmov.x		X(%a6),%fp0
	mov.l		&0x3fff0000,F(%a6)
	clr.l		F+8(%a6)
	fsub.x		F(%a6),%fp0		# Y-F
	fmovm.x		&0xc,-(%sp)		# SAVE FP2-3 WHILE FP0 IS NOT READY
#--SUMMARY: FP0 IS Y-F, A0 IS ADDRESS OF 1/F, FP1 IS K
#--REGISTERS SAVED: FPCR, FP1, FP2

LP1CONT1:
#--AN RE-ENTRY POINT FOR LOGNP1
	fmul.x		(%a0),%fp0		# FP0 IS U = (Y-F)/F
	fmul.x		LOGOF2(%pc),%fp1	# GET K*LOG2 WHILE FP0 IS NOT READY
	fmov.x		%fp0,%fp2
	fmul.x		%fp2,%fp2		# FP2 IS V=U*U
	fmov.x		%fp1,KLOG2(%a6)		# PUT K*LOG2 IN MEMEORY, FREE FP1

#--LOG(1+U) IS APPROXIMATED BY
#--U + V*(A1+U*(A2+U*(A3+U*(A4+U*(A5+U*A6))))) WHICH IS
#--[U + V*(A1+V*(A3+V*A5))]  +  [U*V*(A2+V*(A4+V*A6))]

	fmov.x		%fp2,%fp3
	fmov.x		%fp2,%fp1

	fmul.d		LOGA6(%pc),%fp1		# V*A6
	fmul.d		LOGA5(%pc),%fp2		# V*A5

	fadd.d		LOGA4(%pc),%fp1		# A4+V*A6
	fadd.d		LOGA3(%pc),%fp2		# A3+V*A5

	fmul.x		%fp3,%fp1		# V*(A4+V*A6)
	fmul.x		%fp3,%fp2		# V*(A3+V*A5)

	fadd.d		LOGA2(%pc),%fp1		# A2+V*(A4+V*A6)
	fadd.d		LOGA1(%pc),%fp2		# A1+V*(A3+V*A5)

	fmul.x		%fp3,%fp1		# V*(A2+V*(A4+V*A6))
	add.l		&16,%a0			# ADDRESS OF LOG(F)
	fmul.x		%fp3,%fp2		# V*(A1+V*(A3+V*A5))

	fmul.x		%fp0,%fp1		# U*V*(A2+V*(A4+V*A6))
	fadd.x		%fp2,%fp0		# U+V*(A1+V*(A3+V*A5))

	fadd.x		(%a0),%fp1		# LOG(F)+U*V*(A2+V*(A4+V*A6))
	fmovm.x		(%sp)+,&0x30		# RESTORE FP2-3
	fadd.x		%fp1,%fp0		# FP0 IS LOG(F) + LOG(1+U)

	fmov.l		%d0,%fpcr
	fadd.x		KLOG2(%a6),%fp0		# FINAL ADD
	bra		t_inx2


LOGNEAR1:

# if the input is exactly equal to one, then exit through ld_pzero.
# if these 2 lines weren't here, the correct answer would be returned
# but the INEX2 bit would be set.
	fcmp.b		%fp0,&0x1		# is it equal to one?
	fbeq.l		ld_pzero		# yes

#--REGISTERS SAVED: FPCR, FP1. FP0 CONTAINS THE INPUT.
	fmov.x		%fp0,%fp1
	fsub.s		one(%pc),%fp1		# FP1 IS X-1
	fadd.s		one(%pc),%fp0		# FP0 IS X+1
	fadd.x		%fp1,%fp1		# FP1 IS 2(X-1)
#--LOG(X) = LOG(1+U/2)-LOG(1-U/2) WHICH IS AN ODD POLYNOMIAL
#--IN U, U = 2(X-1)/(X+1) = FP1/FP0

LP1CONT2:
#--THIS IS AN RE-ENTRY POINT FOR LOGNP1
	fdiv.x		%fp0,%fp1		# FP1 IS U
	fmovm.x		&0xc,-(%sp)		# SAVE FP2-3
#--REGISTERS SAVED ARE NOW FPCR,FP1,FP2,FP3
#--LET V=U*U, W=V*V, CALCULATE
#--U + U*V*(B1 + V*(B2 + V*(B3 + V*(B4 + V*B5)))) BY
#--U + U*V*(  [B1 + W*(B3 + W*B5)]  +  [V*(B2 + W*B4)]  )
	fmov.x		%fp1,%fp0
	fmul.x		%fp0,%fp0		# FP0 IS V
	fmov.x		%fp1,SAVEU(%a6)		# STORE U IN MEMORY, FREE FP1
	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# FP1 IS W

	fmov.d		LOGB5(%pc),%fp3
	fmov.d		LOGB4(%pc),%fp2

	fmul.x		%fp1,%fp3		# W*B5
	fmul.x		%fp1,%fp2		# W*B4

	fadd.d		LOGB3(%pc),%fp3		# B3+W*B5
	fadd.d		LOGB2(%pc),%fp2		# B2+W*B4

	fmul.x		%fp3,%fp1		# W*(B3+W*B5), FP3 RELEASED

	fmul.x		%fp0,%fp2		# V*(B2+W*B4)

	fadd.d		LOGB1(%pc),%fp1		# B1+W*(B3+W*B5)
	fmul.x		SAVEU(%a6),%fp0		# FP0 IS U*V

	fadd.x		%fp2,%fp1		# B1+W*(B3+W*B5) + V*(B2+W*B4), FP2 RELEASED
	fmovm.x		(%sp)+,&0x30		# FP2-3 RESTORED

	fmul.x		%fp1,%fp0		# U*V*( [B1+W*(B3+W*B5)] + [V*(B2+W*B4)] )

	fmov.l		%d0,%fpcr
	fadd.x		SAVEU(%a6),%fp0
	bra		t_inx2

#--REGISTERS SAVED FPCR. LOG(-VE) IS INVALID
LOGNEG:
	bra		t_operr

	global		slognd
slognd:
#--ENTRY POINT FOR LOG(X) FOR DENORMALIZED INPUT

	mov.l		&-100,ADJK(%a6)		# INPUT = 2^(ADJK) * FP0

#----normalize the input value by left shifting k bits (k to be determined
#----below), adjusting exponent and storing -k to  ADJK
#----the value TWOTO100 is no longer needed.
#----Note that this code assumes the denormalized input is NON-ZERO.

	movm.l		&0x3f00,-(%sp)		# save some registers  {d2-d7}
	mov.l		(%a0),%d3		# D3 is exponent of smallest norm. #
	mov.l		4(%a0),%d4
	mov.l		8(%a0),%d5		# (D4,D5) is (Hi_X,Lo_X)
	clr.l		%d2			# D2 used for holding K

	tst.l		%d4
	bne.b		Hi_not0

Hi_0:
	mov.l		%d5,%d4
	clr.l		%d5
	mov.l		&32,%d2
	clr.l		%d6
	bfffo		%d4{&0:&32},%d6
	lsl.l		%d6,%d4
	add.l		%d6,%d2			# (D3,D4,D5) is normalized

	mov.l		%d3,X(%a6)
	mov.l		%d4,XFRAC(%a6)
	mov.l		%d5,XFRAC+4(%a6)
	neg.l		%d2
	mov.l		%d2,ADJK(%a6)
	fmov.x		X(%a6),%fp0
	movm.l		(%sp)+,&0xfc		# restore registers {d2-d7}
	lea		X(%a6),%a0
	bra.w		LOGBGN			# begin regular log(X)

Hi_not0:
	clr.l		%d6
	bfffo		%d4{&0:&32},%d6		# find first 1
	mov.l		%d6,%d2			# get k
	lsl.l		%d6,%d4
	mov.l		%d5,%d7			# a copy of D5
	lsl.l		%d6,%d5
	neg.l		%d6
	add.l		&32,%d6
	lsr.l		%d6,%d7
	or.l		%d7,%d4			# (D3,D4,D5) normalized

	mov.l		%d3,X(%a6)
	mov.l		%d4,XFRAC(%a6)
	mov.l		%d5,XFRAC+4(%a6)
	neg.l		%d2
	mov.l		%d2,ADJK(%a6)
	fmov.x		X(%a6),%fp0
	movm.l		(%sp)+,&0xfc		# restore registers {d2-d7}
	lea		X(%a6),%a0
	bra.w		LOGBGN			# begin regular log(X)

	global		slognp1
#--ENTRY POINT FOR LOG(1+X) FOR X FINITE, NON-ZERO, NOT NAN'S
slognp1:
	fmov.x		(%a0),%fp0		# LOAD INPUT
	fabs.x		%fp0			# test magnitude
	fcmp.x		%fp0,LTHOLD(%pc)	# compare with min threshold
	fbgt.w		LP1REAL			# if greater, continue
	fmov.l		%d0,%fpcr
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		(%a0),%fp0		# return signed argument
	bra		t_catch

LP1REAL:
	fmov.x		(%a0),%fp0		# LOAD INPUT
	mov.l		&0x00000000,ADJK(%a6)
	fmov.x		%fp0,%fp1		# FP1 IS INPUT Z
	fadd.s		one(%pc),%fp0		# X := ROUND(1+Z)
	fmov.x		%fp0,X(%a6)
	mov.w		XFRAC(%a6),XDCARE(%a6)
	mov.l		X(%a6),%d1
	cmp.l		%d1,&0
	ble.w		LP1NEG0			# LOG OF ZERO OR -VE
	cmp.l		%d1,&0x3ffe8000 	# IS BOUNDS [1/2,3/2]?
	blt.w		LOGMAIN
	cmp.l		%d1,&0x3fffc000
	bgt.w		LOGMAIN 
#--IF 1+Z > 3/2 OR 1+Z < 1/2, THEN X, WHICH IS ROUNDING 1+Z,
#--CONTAINS AT LEAST 63 BITS OF INFORMATION OF Z. IN THAT CASE,
#--SIMPLY INVOKE LOG(X) FOR LOG(1+Z).

LP1NEAR1:
#--NEXT SEE IF EXP(-1/16) < X < EXP(1/16)
	cmp.l		%d1,&0x3ffef07d
	blt.w		LP1CARE
	cmp.l		%d1,&0x3fff8841
	bgt.w		LP1CARE

LP1ONE16:
#--EXP(-1/16) < X < EXP(1/16). LOG(1+Z) = LOG(1+U/2) - LOG(1-U/2)
#--WHERE U = 2Z/(2+Z) = 2Z/(1+X).
	fadd.x		%fp1,%fp1		# FP1 IS 2Z
	fadd.s		one(%pc),%fp0		# FP0 IS 1+X
#--U = FP1/FP0
	bra.w		LP1CONT2

LP1CARE:
#--HERE WE USE THE USUAL TABLE DRIVEN APPROACH. CARE HAS TO BE
#--TAKEN BECAUSE 1+Z CAN HAVE 67 BITS OF INFORMATION AND WE MUST
#--PRESERVE ALL THE INFORMATION. BECAUSE 1+Z IS IN [1/2,3/2],
#--THERE ARE ONLY TWO CASES.
#--CASE 1: 1+Z < 1, THEN K = -1 AND Y-F = (2-F) + 2Z
#--CASE 2: 1+Z > 1, THEN K = 0  AND Y-F = (1-F) + Z
#--ON RETURNING TO LP1CONT1, WE MUST HAVE K IN FP1, ADDRESS OF
#--(1/F) IN A0, Y-F IN FP0, AND FP2 SAVED.

	mov.l		XFRAC(%a6),FFRAC(%a6)
	and.l		&0xFE000000,FFRAC(%a6)
	or.l		&0x01000000,FFRAC(%a6)	# F OBTAINED
	cmp.l		%d1,&0x3FFF8000		# SEE IF 1+Z > 1
	bge.b		KISZERO

KISNEG1:
	fmov.s		TWO(%pc),%fp0
	mov.l		&0x3fff0000,F(%a6)
	clr.l		F+8(%a6)
	fsub.x		F(%a6),%fp0		# 2-F
	mov.l		FFRAC(%a6),%d1
	and.l		&0x7E000000,%d1
	asr.l		&8,%d1
	asr.l		&8,%d1
	asr.l		&4,%d1			# D0 CONTAINS DISPLACEMENT FOR 1/F
	fadd.x		%fp1,%fp1		# GET 2Z
	fmovm.x		&0xc,-(%sp)		# SAVE FP2  {%fp2/%fp3}
	fadd.x		%fp1,%fp0		# FP0 IS Y-F = (2-F)+2Z
	lea		LOGTBL(%pc),%a0		# A0 IS ADDRESS OF 1/F
	add.l		%d1,%a0
	fmov.s		negone(%pc),%fp1	# FP1 IS K = -1
	bra.w		LP1CONT1

KISZERO:
	fmov.s		one(%pc),%fp0
	mov.l		&0x3fff0000,F(%a6)
	clr.l		F+8(%a6)
	fsub.x		F(%a6),%fp0		# 1-F
	mov.l		FFRAC(%a6),%d1
	and.l		&0x7E000000,%d1
	asr.l		&8,%d1
	asr.l		&8,%d1
	asr.l		&4,%d1
	fadd.x		%fp1,%fp0		# FP0 IS Y-F
	fmovm.x		&0xc,-(%sp)		# FP2 SAVED {%fp2/%fp3}
	lea		LOGTBL(%pc),%a0
	add.l		%d1,%a0			# A0 IS ADDRESS OF 1/F
	fmov.s		zero(%pc),%fp1		# FP1 IS K = 0
	bra.w		LP1CONT1

LP1NEG0:
#--FPCR SAVED. D0 IS X IN COMPACT FORM.
	cmp.l		%d1,&0
	blt.b		LP1NEG
LP1ZERO:
	fmov.s		negone(%pc),%fp0

	fmov.l		%d0,%fpcr
	bra		t_dz

LP1NEG:
	fmov.s		zero(%pc),%fp0

	fmov.l		%d0,%fpcr
	bra		t_operr

	global		slognp1d
#--ENTRY POINT FOR LOG(1+Z) FOR DENORMALIZED INPUT
# Simply return the denorm
slognp1d:
	bra		t_extdnrm

#########################################################################
# satanh():  computes the inverse hyperbolic tangent of a norm input	#
# satanhd(): computes the inverse hyperbolic tangent of a denorm input	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT **************************************************************	# 
#	fp0 = arctanh(X)						#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 3 ulps in	64 significant bit,	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#									#
#	ATANH								#
#	1. If |X| >= 1, go to 3.					#
#									#
#	2. (|X| < 1) Calculate atanh(X) by				#
#		sgn := sign(X)						#
#		y := |X|						#
#		z := 2y/(1-y)						#
#		atanh(X) := sgn * (1/2) * logp1(z)			#
#		Exit.							#
#									#
#	3. If |X| > 1, go to 5.						#
#									#
#	4. (|X| = 1) Generate infinity with an appropriate sign and	#
#		divide-by-zero by					#
#		sgn := sign(X)						#
#		atan(X) := sgn / (+0).					#
#		Exit.							#
#									#
#	5. (|X| > 1) Generate an invalid operation by 0 * infinity.	#
#		Exit.							#
#									#
#########################################################################

	global		satanh
satanh:
	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	and.l		&0x7FFFFFFF,%d1
	cmp.l		%d1,&0x3FFF8000
	bge.b		ATANHBIG

#--THIS IS THE USUAL CASE, |X| < 1
#--Y = |X|, Z = 2Y/(1-Y), ATANH(X) = SIGN(X) * (1/2) * LOG1P(Z).

	fabs.x		(%a0),%fp0		# Y = |X|
	fmov.x		%fp0,%fp1
	fneg.x		%fp1			# -Y
	fadd.x		%fp0,%fp0		# 2Y
	fadd.s		&0x3F800000,%fp1	# 1-Y
	fdiv.x		%fp1,%fp0		# 2Y/(1-Y)
	mov.l		(%a0),%d1
	and.l		&0x80000000,%d1
	or.l		&0x3F000000,%d1		# SIGN(X)*HALF
	mov.l		%d1,-(%sp)

	mov.l		%d0,-(%sp)		# save rnd prec,mode
	clr.l		%d0			# pass ext prec,RN
	fmovm.x		&0x01,-(%sp)		# save Z on stack
	lea		(%sp),%a0		# pass ptr to Z
	bsr		slognp1			# LOG1P(Z)
	add.l		&0xc,%sp		# clear Z from stack

	mov.l		(%sp)+,%d0		# fetch old prec,mode
	fmov.l		%d0,%fpcr		# load it
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.s		(%sp)+,%fp0
	bra		t_catch

ATANHBIG:
	fabs.x		(%a0),%fp0		# |X|
	fcmp.s		%fp0,&0x3F800000
	fbgt		t_operr
	bra		t_dz

	global		satanhd
#--ATANH(X) = X FOR DENORMALIZED X
satanhd:
	bra		t_extdnrm

#########################################################################
# slog10():  computes the base-10 logarithm of a normalized input	#
# slog10d(): computes the base-10 logarithm of a denormalized input	#
# slog2():   computes the base-2 logarithm of a normalized input	#
# slog2d():  computes the base-2 logarithm of a denormalized input	#
#									#
# INPUT *************************************************************** #
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT **************************************************************	#
#	fp0 = log_10(X) or log_2(X)					#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 1.7 ulps in 64 significant bit,	#
#	i.e. within 0.5003 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#									#
#       slog10d:							#
#									#
#       Step 0.	If X < 0, create a NaN and raise the invalid operation	#
#               flag. Otherwise, save FPCR in D1; set FpCR to default.	#
#       Notes:  Default means round-to-nearest mode, no floating-point	#
#               traps, and precision control = double extended.		#
#									#
#       Step 1. Call slognd to obtain Y = log(X), the natural log of X.	#
#       Notes:  Even if X is denormalized, log(X) is always normalized.	#
#									#
#       Step 2.  Compute log_10(X) = log(X) * (1/log(10)).		#
#            2.1 Restore the user FPCR					#
#            2.2 Return ans := Y * INV_L10.				#
#									#
#       slog10: 							#
#									#
#       Step 0. If X < 0, create a NaN and raise the invalid operation	#
#               flag. Otherwise, save FPCR in D1; set FpCR to default.	#
#       Notes:  Default means round-to-nearest mode, no floating-point	#
#               traps, and precision control = double extended.		#
#									#
#       Step 1. Call sLogN to obtain Y = log(X), the natural log of X.	#
#									#
#       Step 2.   Compute log_10(X) = log(X) * (1/log(10)).		#
#            2.1  Restore the user FPCR					#
#            2.2  Return ans := Y * INV_L10.				#
#									#
#       sLog2d:								#
#									#
#       Step 0. If X < 0, create a NaN and raise the invalid operation	#
#               flag. Otherwise, save FPCR in D1; set FpCR to default.	#
#       Notes:  Default means round-to-nearest mode, no floating-point	#
#               traps, and precision control = double extended.		#
#									#
#       Step 1. Call slognd to obtain Y = log(X), the natural log of X.	#
#       Notes:  Even if X is denormalized, log(X) is always normalized.	#
#									#
#       Step 2.   Compute log_10(X) = log(X) * (1/log(2)).		#
#            2.1  Restore the user FPCR					#
#            2.2  Return ans := Y * INV_L2.				#
#									#
#       sLog2:								#
#									#
#       Step 0. If X < 0, create a NaN and raise the invalid operation	#
#               flag. Otherwise, save FPCR in D1; set FpCR to default.	#
#       Notes:  Default means round-to-nearest mode, no floating-point	#
#               traps, and precision control = double extended.		#
#									#
#       Step 1. If X is not an integer power of two, i.e., X != 2^k,	#
#               go to Step 3.						#
#									#
#       Step 2.   Return k.						#
#            2.1  Get integer k, X = 2^k.				#
#            2.2  Restore the user FPCR.				#
#            2.3  Return ans := convert-to-double-extended(k).		#
#									#
#       Step 3. Call sLogN to obtain Y = log(X), the natural log of X.	#
#									#
#       Step 4.   Compute log_2(X) = log(X) * (1/log(2)).		#
#            4.1  Restore the user FPCR					#
#            4.2  Return ans := Y * INV_L2.				#
#									#
#########################################################################

INV_L10:
	long		0x3FFD0000,0xDE5BD8A9,0x37287195,0x00000000

INV_L2:
	long		0x3FFF0000,0xB8AA3B29,0x5C17F0BC,0x00000000

	global		slog10
#--entry point for Log10(X), X is normalized
slog10:
	fmov.b		&0x1,%fp0
	fcmp.x		%fp0,(%a0)		# if operand == 1,
	fbeq.l		ld_pzero		# return an EXACT zero

	mov.l		(%a0),%d1
	blt.w		invalid
	mov.l		%d0,-(%sp)
	clr.l		%d0
	bsr		slogn			# log(X), X normal.
	fmov.l		(%sp)+,%fpcr
	fmul.x		INV_L10(%pc),%fp0
	bra		t_inx2

	global		slog10d
#--entry point for Log10(X), X is denormalized
slog10d:
	mov.l		(%a0),%d1
	blt.w		invalid
	mov.l		%d0,-(%sp)
	clr.l		%d0
	bsr		slognd			# log(X), X denorm.
	fmov.l		(%sp)+,%fpcr
	fmul.x		INV_L10(%pc),%fp0
	bra		t_minx2

	global		slog2
#--entry point for Log2(X), X is normalized
slog2:
	mov.l		(%a0),%d1
	blt.w		invalid

	mov.l		8(%a0),%d1
	bne.b		continue		# X is not 2^k

	mov.l		4(%a0),%d1
	and.l		&0x7FFFFFFF,%d1
	bne.b		continue

#--X = 2^k.
	mov.w		(%a0),%d1
	and.l		&0x00007FFF,%d1
	sub.l		&0x3FFF,%d1
	beq.l		ld_pzero
	fmov.l		%d0,%fpcr
	fmov.l		%d1,%fp0
	bra		t_inx2

continue:
	mov.l		%d0,-(%sp)
	clr.l		%d0
	bsr		slogn			# log(X), X normal.
	fmov.l		(%sp)+,%fpcr
	fmul.x		INV_L2(%pc),%fp0
	bra		t_inx2

invalid:
	bra		t_operr

	global		slog2d
#--entry point for Log2(X), X is denormalized
slog2d:
	mov.l		(%a0),%d1
	blt.w		invalid
	mov.l		%d0,-(%sp)
	clr.l		%d0
	bsr		slognd			# log(X), X denorm.
	fmov.l		(%sp)+,%fpcr
	fmul.x		INV_L2(%pc),%fp0
	bra		t_minx2

#########################################################################
# stwotox():  computes 2**X for a normalized input			#
# stwotoxd(): computes 2**X for a denormalized input			#
# stentox():  computes 10**X for a normalized input			#
# stentoxd(): computes 10**X for a denormalized input			#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision input			#
#	d0 = round precision,mode					#
#									#
# OUTPUT **************************************************************	#
#	fp0 = 2**X or 10**X						#
#									#
# ACCURACY and MONOTONICITY *******************************************	#
#	The returned result is within 2 ulps in 64 significant bit, 	#
#	i.e. within 0.5001 ulp to 53 bits if the result is subsequently	#
#	rounded to double precision. The result is provably monotonic	#
#	in double precision.						#
#									#
# ALGORITHM ***********************************************************	#
#									#
#	twotox								#
#	1. If |X| > 16480, go to ExpBig.				#
#									#
#	2. If |X| < 2**(-70), go to ExpSm.				#
#									#
#	3. Decompose X as X = N/64 + r where |r| <= 1/128. Furthermore	#
#		decompose N as						#
#		 N = 64(M + M') + j,  j = 0,1,2,...,63.			#
#									#
#	4. Overwrite r := r * log2. Then				#
#		2**X = 2**(M') * 2**(M) * 2**(j/64) * exp(r).		#
#		Go to expr to compute that expression.			#
#									#
#	tentox								#
#	1. If |X| > 16480*log_10(2) (base 10 log of 2), go to ExpBig.	#
#									#
#	2. If |X| < 2**(-70), go to ExpSm.				#
#									#
#	3. Set y := X*log_2(10)*64 (base 2 log of 10). Set		#
#		N := round-to-int(y). Decompose N as			#
#		 N = 64(M + M') + j,  j = 0,1,2,...,63.			#
#									#
#	4. Define r as							#
#		r := ((X - N*L1)-N*L2) * L10				#
#		where L1, L2 are the leading and trailing parts of 	#
#		log_10(2)/64 and L10 is the natural log of 10. Then	#
#		10**X = 2**(M') * 2**(M) * 2**(j/64) * exp(r).		#
#		Go to expr to compute that expression.			#
#									#
#	expr								#
#	1. Fetch 2**(j/64) from table as Fact1 and Fact2.		#
#									#
#	2. Overwrite Fact1 and Fact2 by					#
#		Fact1 := 2**(M) * Fact1					#
#		Fact2 := 2**(M) * Fact2					#
#		Thus Fact1 + Fact2 = 2**(M) * 2**(j/64).		#
#									#
#	3. Calculate P where 1 + P approximates exp(r):			#
#		P = r + r*r*(A1+r*(A2+...+r*A5)).			#
#									#
#	4. Let AdjFact := 2**(M'). Return				#
#		AdjFact * ( Fact1 + ((Fact1*P) + Fact2) ).		#
#		Exit.							#
#									#
#	ExpBig								#
#	1. Generate overflow by Huge * Huge if X > 0; otherwise, 	#
#	        generate underflow by Tiny * Tiny.			#
#									#
#	ExpSm								#
#	1. Return 1 + X.						#
#									#
#########################################################################

L2TEN64:
	long		0x406A934F,0x0979A371	# 64LOG10/LOG2
L10TWO1:
	long		0x3F734413,0x509F8000	# LOG2/64LOG10

L10TWO2:
	long		0xBFCD0000,0xC0219DC1,0xDA994FD2,0x00000000

LOG10:	long		0x40000000,0x935D8DDD,0xAAA8AC17,0x00000000

LOG2:	long		0x3FFE0000,0xB17217F7,0xD1CF79AC,0x00000000

EXPA5:	long		0x3F56C16D,0x6F7BD0B2
EXPA4:	long		0x3F811112,0x302C712C
EXPA3:	long		0x3FA55555,0x55554CC1
EXPA2:	long		0x3FC55555,0x55554A54
EXPA1:	long		0x3FE00000,0x00000000,0x00000000,0x00000000

TEXPTBL:
	long		0x3FFF0000,0x80000000,0x00000000,0x3F738000
	long		0x3FFF0000,0x8164D1F3,0xBC030773,0x3FBEF7CA
	long		0x3FFF0000,0x82CD8698,0xAC2BA1D7,0x3FBDF8A9
	long		0x3FFF0000,0x843A28C3,0xACDE4046,0x3FBCD7C9
	long		0x3FFF0000,0x85AAC367,0xCC487B15,0xBFBDE8DA
	long		0x3FFF0000,0x871F6196,0x9E8D1010,0x3FBDE85C
	long		0x3FFF0000,0x88980E80,0x92DA8527,0x3FBEBBF1
	long		0x3FFF0000,0x8A14D575,0x496EFD9A,0x3FBB80CA
	long		0x3FFF0000,0x8B95C1E3,0xEA8BD6E7,0xBFBA8373
	long		0x3FFF0000,0x8D1ADF5B,0x7E5BA9E6,0xBFBE9670
	long		0x3FFF0000,0x8EA4398B,0x45CD53C0,0x3FBDB700
	long		0x3FFF0000,0x9031DC43,0x1466B1DC,0x3FBEEEB0
	long		0x3FFF0000,0x91C3D373,0xAB11C336,0x3FBBFD6D
	long		0x3FFF0000,0x935A2B2F,0x13E6E92C,0xBFBDB319
	long		0x3FFF0000,0x94F4EFA8,0xFEF70961,0x3FBDBA2B
	long		0x3FFF0000,0x96942D37,0x20185A00,0x3FBE91D5
	long		0x3FFF0000,0x9837F051,0x8DB8A96F,0x3FBE8D5A
	long		0x3FFF0000,0x99E04593,0x20B7FA65,0xBFBCDE7B
	long		0x3FFF0000,0x9B8D39B9,0xD54E5539,0xBFBEBAAF
	long		0x3FFF0000,0x9D3ED9A7,0x2CFFB751,0xBFBD86DA
	long		0x3FFF0000,0x9EF53260,0x91A111AE,0xBFBEBEDD
	long		0x3FFF0000,0xA0B0510F,0xB9714FC2,0x3FBCC96E
	long		0x3FFF0000,0xA2704303,0x0C496819,0xBFBEC90B
	long		0x3FFF0000,0xA43515AE,0x09E6809E,0x3FBBD1DB
	long		0x3FFF0000,0xA5FED6A9,0xB15138EA,0x3FBCE5EB
	long		0x3FFF0000,0xA7CD93B4,0xE965356A,0xBFBEC274
	long		0x3FFF0000,0xA9A15AB4,0xEA7C0EF8,0x3FBEA83C
	long		0x3FFF0000,0xAB7A39B5,0xA93ED337,0x3FBECB00
	long		0x3FFF0000,0xAD583EEA,0x42A14AC6,0x3FBE9301
	long		0x3FFF0000,0xAF3B78AD,0x690A4375,0xBFBD8367
	long		0x3FFF0000,0xB123F581,0xD2AC2590,0xBFBEF05F
	long		0x3FFF0000,0xB311C412,0xA9112489,0x3FBDFB3C
	long		0x3FFF0000,0xB504F333,0xF9DE6484,0x3FBEB2FB
	long		0x3FFF0000,0xB6FD91E3,0x28D17791,0x3FBAE2CB
	long		0x3FFF0000,0xB8FBAF47,0x62FB9EE9,0x3FBCDC3C
	long		0x3FFF0000,0xBAFF5AB2,0x133E45FB,0x3FBEE9AA
	long		0x3FFF0000,0xBD08A39F,0x580C36BF,0xBFBEAEFD
	long		0x3FFF0000,0xBF1799B6,0x7A731083,0xBFBCBF51
	long		0x3FFF0000,0xC12C4CCA,0x66709456,0x3FBEF88A
	long		0x3FFF0000,0xC346CCDA,0x24976407,0x3FBD83B2
	long		0x3FFF0000,0xC5672A11,0x5506DADD,0x3FBDF8AB
	long		0x3FFF0000,0xC78D74C8,0xABB9B15D,0xBFBDFB17
	long		0x3FFF0000,0xC9B9BD86,0x6E2F27A3,0xBFBEFE3C
	long		0x3FFF0000,0xCBEC14FE,0xF2727C5D,0xBFBBB6F8
	long		0x3FFF0000,0xCE248C15,0x1F8480E4,0xBFBCEE53
	long		0x3FFF0000,0xD06333DA,0xEF2B2595,0xBFBDA4AE
	long		0x3FFF0000,0xD2A81D91,0xF12AE45A,0x3FBC9124
	long		0x3FFF0000,0xD4F35AAB,0xCFEDFA1F,0x3FBEB243
	long		0x3FFF0000,0xD744FCCA,0xD69D6AF4,0x3FBDE69A
	long		0x3FFF0000,0xD99D15C2,0x78AFD7B6,0xBFB8BC61
	long		0x3FFF0000,0xDBFBB797,0xDAF23755,0x3FBDF610
	long		0x3FFF0000,0xDE60F482,0x5E0E9124,0xBFBD8BE1
	long		0x3FFF0000,0xE0CCDEEC,0x2A94E111,0x3FBACB12
	long		0x3FFF0000,0xE33F8972,0xBE8A5A51,0x3FBB9BFE
	long		0x3FFF0000,0xE5B906E7,0x7C8348A8,0x3FBCF2F4
	long		0x3FFF0000,0xE8396A50,0x3C4BDC68,0x3FBEF22F
	long		0x3FFF0000,0xEAC0C6E7,0xDD24392F,0xBFBDBF4A
	long		0x3FFF0000,0xED4F301E,0xD9942B84,0x3FBEC01A
	long		0x3FFF0000,0xEFE4B99B,0xDCDAF5CB,0x3FBE8CAC
	long		0x3FFF0000,0xF281773C,0x59FFB13A,0xBFBCBB3F
	long		0x3FFF0000,0xF5257D15,0x2486CC2C,0x3FBEF73A
	long		0x3FFF0000,0xF7D0DF73,0x0AD13BB9,0xBFB8B795
	long		0x3FFF0000,0xFA83B2DB,0x722A033A,0x3FBEF84B
	long		0x3FFF0000,0xFD3E0C0C,0xF486C175,0xBFBEF581

	set		INT,L_SCR1

	set		X,FP_SCR0
	set		XDCARE,X+2
	set		XFRAC,X+4

	set		ADJFACT,FP_SCR0

	set		FACT1,FP_SCR0
	set		FACT1HI,FACT1+4
	set		FACT1LOW,FACT1+8

	set		FACT2,FP_SCR1
	set		FACT2HI,FACT2+4
	set		FACT2LOW,FACT2+8

	global		stwotox
#--ENTRY POINT FOR 2**(X), HERE X IS FINITE, NON-ZERO, AND NOT NAN'S
stwotox:
	fmovm.x		(%a0),&0x80		# LOAD INPUT

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	fmov.x		%fp0,X(%a6)
	and.l		&0x7FFFFFFF,%d1

	cmp.l		%d1,&0x3FB98000		# |X| >= 2**(-70)?
	bge.b		TWOOK1
	bra.w		EXPBORS

TWOOK1:
	cmp.l		%d1,&0x400D80C0		# |X| > 16480?
	ble.b		TWOMAIN
	bra.w		EXPBORS

TWOMAIN:
#--USUAL CASE, 2^(-70) <= |X| <= 16480

	fmov.x		%fp0,%fp1
	fmul.s		&0x42800000,%fp1	# 64 * X
	fmov.l		%fp1,INT(%a6)		# N = ROUND-TO-INT(64 X)
	mov.l		%d2,-(%sp)
	lea		TEXPTBL(%pc),%a1	# LOAD ADDRESS OF TABLE OF 2^(J/64)
	fmov.l		INT(%a6),%fp1		# N --> FLOATING FMT
	mov.l		INT(%a6),%d1
	mov.l		%d1,%d2
	and.l		&0x3F,%d1		# D0 IS J
	asl.l		&4,%d1			# DISPLACEMENT FOR 2^(J/64)
	add.l		%d1,%a1			# ADDRESS FOR 2^(J/64)
	asr.l		&6,%d2			# d2 IS L, N = 64L + J
	mov.l		%d2,%d1
	asr.l		&1,%d1			# D0 IS M
	sub.l		%d1,%d2			# d2 IS M', N = 64(M+M') + J
	add.l		&0x3FFF,%d2

#--SUMMARY: a1 IS ADDRESS FOR THE LEADING PORTION OF 2^(J/64),
#--D0 IS M WHERE N = 64(M+M') + J. NOTE THAT |M| <= 16140 BY DESIGN.
#--ADJFACT = 2^(M').
#--REGISTERS SAVED SO FAR ARE (IN ORDER) FPCR, D0, FP1, a1, AND FP2.

	fmovm.x		&0x0c,-(%sp)		# save fp2/fp3

	fmul.s		&0x3C800000,%fp1	# (1/64)*N
	mov.l		(%a1)+,FACT1(%a6)
	mov.l		(%a1)+,FACT1HI(%a6)
	mov.l		(%a1)+,FACT1LOW(%a6)
	mov.w		(%a1)+,FACT2(%a6)

	fsub.x		%fp1,%fp0		# X - (1/64)*INT(64 X)

	mov.w		(%a1)+,FACT2HI(%a6)
	clr.w		FACT2HI+2(%a6)
	clr.l		FACT2LOW(%a6)
	add.w		%d1,FACT1(%a6)
	fmul.x		LOG2(%pc),%fp0		# FP0 IS R
	add.w		%d1,FACT2(%a6)

	bra.w		expr

EXPBORS:
#--FPCR, D0 SAVED
	cmp.l		%d1,&0x3FFF8000
	bgt.b		TEXPBIG

#--|X| IS SMALL, RETURN 1 + X

	fmov.l		%d0,%fpcr		# restore users round prec,mode
	fadd.s		&0x3F800000,%fp0	# RETURN 1 + X
	bra		t_pinx2

TEXPBIG:
#--|X| IS LARGE, GENERATE OVERFLOW IF X > 0; ELSE GENERATE UNDERFLOW
#--REGISTERS SAVE SO FAR ARE FPCR AND  D0
	mov.l		X(%a6),%d1
	cmp.l		%d1,&0
	blt.b		EXPNEG

	bra		t_ovfl2			# t_ovfl expects positive value

EXPNEG:
	bra		t_unfl2			# t_unfl expects positive value

	global		stwotoxd
stwotoxd:
#--ENTRY POINT FOR 2**(X) FOR DENORMALIZED ARGUMENT

	fmov.l		%d0,%fpcr		# set user's rounding mode/precision
	fmov.s		&0x3F800000,%fp0	# RETURN 1 + X
	mov.l		(%a0),%d1
	or.l		&0x00800001,%d1
	fadd.s		%d1,%fp0
	bra		t_pinx2

	global		stentox
#--ENTRY POINT FOR 10**(X), HERE X IS FINITE, NON-ZERO, AND NOT NAN'S
stentox:
	fmovm.x		(%a0),&0x80		# LOAD INPUT

	mov.l		(%a0),%d1
	mov.w		4(%a0),%d1
	fmov.x		%fp0,X(%a6)
	and.l		&0x7FFFFFFF,%d1

	cmp.l		%d1,&0x3FB98000		# |X| >= 2**(-70)?
	bge.b		TENOK1
	bra.w		EXPBORS

TENOK1:
	cmp.l		%d1,&0x400B9B07		# |X| <= 16480*log2/log10 ?
	ble.b		TENMAIN
	bra.w		EXPBORS

TENMAIN:
#--USUAL CASE, 2^(-70) <= |X| <= 16480 LOG 2 / LOG 10

	fmov.x		%fp0,%fp1
	fmul.d		L2TEN64(%pc),%fp1	# X*64*LOG10/LOG2
	fmov.l		%fp1,INT(%a6)		# N=INT(X*64*LOG10/LOG2)
	mov.l		%d2,-(%sp)
	lea		TEXPTBL(%pc),%a1	# LOAD ADDRESS OF TABLE OF 2^(J/64)
	fmov.l		INT(%a6),%fp1		# N --> FLOATING FMT
	mov.l		INT(%a6),%d1
	mov.l		%d1,%d2
	and.l		&0x3F,%d1		# D0 IS J
	asl.l		&4,%d1			# DISPLACEMENT FOR 2^(J/64)
	add.l		%d1,%a1			# ADDRESS FOR 2^(J/64)
	asr.l		&6,%d2			# d2 IS L, N = 64L + J
	mov.l		%d2,%d1
	asr.l		&1,%d1			# D0 IS M
	sub.l		%d1,%d2			# d2 IS M', N = 64(M+M') + J
	add.l		&0x3FFF,%d2

#--SUMMARY: a1 IS ADDRESS FOR THE LEADING PORTION OF 2^(J/64),
#--D0 IS M WHERE N = 64(M+M') + J. NOTE THAT |M| <= 16140 BY DESIGN.
#--ADJFACT = 2^(M').
#--REGISTERS SAVED SO FAR ARE (IN ORDER) FPCR, D0, FP1, a1, AND FP2.
	fmovm.x		&0x0c,-(%sp)		# save fp2/fp3

	fmov.x		%fp1,%fp2

	fmul.d		L10TWO1(%pc),%fp1	# N*(LOG2/64LOG10)_LEAD
	mov.l		(%a1)+,FACT1(%a6)

	fmul.x		L10TWO2(%pc),%fp2	# N*(LOG2/64LOG10)_TRAIL

	mov.l		(%a1)+,FACT1HI(%a6)
	mov.l		(%a1)+,FACT1LOW(%a6)
	fsub.x		%fp1,%fp0		# X - N L_LEAD
	mov.w		(%a1)+,FACT2(%a6)

	fsub.x		%fp2,%fp0		# X - N L_TRAIL

	mov.w		(%a1)+,FACT2HI(%a6)
	clr.w		FACT2HI+2(%a6)
	clr.l		FACT2LOW(%a6)

	fmul.x		LOG10(%pc),%fp0		# FP0 IS R
	add.w		%d1,FACT1(%a6)
	add.w		%d1,FACT2(%a6)

expr:
#--FPCR, FP2, FP3 ARE SAVED IN ORDER AS SHOWN.
#--ADJFACT CONTAINS 2**(M'), FACT1 + FACT2 = 2**(M) * 2**(J/64).
#--FP0 IS R. THE FOLLOWING CODE COMPUTES
#--	2**(M'+M) * 2**(J/64) * EXP(R)

	fmov.x		%fp0,%fp1
	fmul.x		%fp1,%fp1		# FP1 IS S = R*R

	fmov.d		EXPA5(%pc),%fp2		# FP2 IS A5
	fmov.d		EXPA4(%pc),%fp3		# FP3 IS A4

	fmul.x		%fp1,%fp2		# FP2 IS S*A5
	fmul.x		%fp1,%fp3		# FP3 IS S*A4

	fadd.d		EXPA3(%pc),%fp2		# FP2 IS A3+S*A5
	fadd.d		EXPA2(%pc),%fp3		# FP3 IS A2+S*A4

	fmul.x		%fp1,%fp2		# FP2 IS S*(A3+S*A5)
	fmul.x		%fp1,%fp3		# FP3 IS S*(A2+S*A4)

	fadd.d		EXPA1(%pc),%fp2		# FP2 IS A1+S*(A3+S*A5)
	fmul.x		%fp0,%fp3		# FP3 IS R*S*(A2+S*A4)

	fmul.x		%fp1,%fp2		# FP2 IS S*(A1+S*(A3+S*A5))
	fadd.x		%fp3,%fp0		# FP0 IS R+R*S*(A2+S*A4)
	fadd.x		%fp2,%fp0		# FP0 IS EXP(R) - 1

	fmovm.x		(%sp)+,&0x30		# restore fp2/fp3

#--FINAL RECONSTRUCTION PROCESS
#--EXP(X) = 2^M*2^(J/64) + 2^M*2^(J/64)*(EXP(R)-1)  -  (1 OR 0)

	fmul.x		FACT1(%a6),%fp0
	fadd.x		FACT2(%a6),%fp0
	fadd.x		FACT1(%a6),%fp0

	fmov.l		%d0,%fpcr		# restore users round prec,mode
	mov.w		%d2,ADJFACT(%a6)	# INSERT EXPONENT
	mov.l		(%sp)+,%d2
	mov.l		&0x80000000,ADJFACT+4(%a6)
	clr.l		ADJFACT+8(%a6)
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.x		ADJFACT(%a6),%fp0	# FINAL ADJUSTMENT
	bra		t_catch

	global		stentoxd
stentoxd:
#--ENTRY POINT FOR 10**(X) FOR DENORMALIZED ARGUMENT

	fmov.l		%d0,%fpcr		# set user's rounding mode/precision
	fmov.s		&0x3F800000,%fp0	# RETURN 1 + X
	mov.l		(%a0),%d1
	or.l		&0x00800001,%d1
	fadd.s		%d1,%fp0
	bra		t_pinx2

#########################################################################
# smovcr(): returns the ROM constant at the offset specified in d1	#
#	    rounded to the mode and precision specified in d0. 		#
#									#
# INPUT	***************************************************************	#
# 	d0 = rnd prec,mode						#
#	d1 = ROM offset							#
#									#
# OUTPUT **************************************************************	#
#	fp0 = the ROM constant rounded to the user's rounding mode,prec	#
#									#
#########################################################################

	global		smovcr
smovcr:
	mov.l		%d1,-(%sp)		# save rom offset for a sec

	lsr.b		&0x4,%d0		# shift ctrl bits to lo
	mov.l		%d0,%d1			# make a copy 
	andi.w		&0x3,%d1		# extract rnd mode
	andi.w		&0xc,%d0		# extract rnd prec
	swap		%d0			# put rnd prec in hi
	mov.w		%d1,%d0			# put rnd mode in lo

	mov.l		(%sp)+,%d1		# get rom offset

#
# check range of offset
#
	tst.b		%d1			# if zero, offset is to pi
	beq.b		pi_tbl			# it is pi
	cmpi.b		%d1,&0x0a		# check range $01 - $0a
	ble.b		z_val			# if in this range, return zero
	cmpi.b		%d1,&0x0e		# check range $0b - $0e
	ble.b		sm_tbl			# valid constants in this range
	cmpi.b		%d1,&0x2f		# check range $10 - $2f
	ble.b		z_val			# if in this range, return zero 
	cmpi.b		%d1,&0x3f		# check range $30 - $3f
	ble.b		bg_tbl			# valid constants in this range

z_val:
	bra.l		ld_pzero		# return a zero

#
# the answer is PI rounded to the proper precision.
#
# fetch a pointer to the answer table relating to the proper rounding
# precision.
#
pi_tbl:
	tst.b		%d0			# is rmode RN?
	bne.b		pi_not_rn		# no
pi_rn:
	lea.l		PIRN(%pc),%a0		# yes; load PI RN table addr
	bra.w		set_finx
pi_not_rn:
	cmpi.b		%d0,&rp_mode		# is rmode RP?
	beq.b		pi_rp			# yes
pi_rzrm:
	lea.l		PIRZRM(%pc),%a0		# no; load PI RZ,RM table addr
	bra.b		set_finx
pi_rp:
	lea.l		PIRP(%pc),%a0		# load PI RP table addr
	bra.b		set_finx

#
# the answer is one of:
#	$0B	log10(2)	(inexact)
#	$0C	e		(inexact)
#	$0D	log2(e)		(inexact)
#	$0E	log10(e)	(exact)
# 
# fetch a pointer to the answer table relating to the proper rounding
# precision.
#
sm_tbl:
	subi.b		&0xb,%d1		# make offset in 0-4 range
	tst.b		%d0			# is rmode RN?
	bne.b		sm_not_rn		# no
sm_rn:
	lea.l		SMALRN(%pc),%a0		# yes; load RN table addr
sm_tbl_cont:
	cmpi.b		%d1,&0x2		# is result log10(e)?
	ble.b		set_finx		# no; answer is inexact
	bra.b		no_finx			# yes; answer is exact
sm_not_rn:
	cmpi.b		%d0,&rp_mode		# is rmode RP?
	beq.b		sm_rp			# yes
sm_rzrm:
	lea.l		SMALRZRM(%pc),%a0	# no; load RZ,RM table addr
	bra.b		sm_tbl_cont
sm_rp:
	lea.l		SMALRP(%pc),%a0		# load RP table addr
	bra.b		sm_tbl_cont

#
# the answer is one of:
#	$30	ln(2)		(inexact)
#	$31	ln(10)		(inexact)
#	$32	10^0		(exact)
#	$33	10^1		(exact)
#	$34	10^2		(exact)
#	$35	10^4		(exact)
#	$36	10^8		(exact)
#	$37	10^16		(exact)
#	$38	10^32		(inexact)
#	$39	10^64		(inexact)
#	$3A	10^128		(inexact)
#	$3B	10^256		(inexact)
#	$3C	10^512		(inexact)
#	$3D	10^1024		(inexact)
#	$3E	10^2048		(inexact)
#	$3F	10^4096		(inexact)
#
# fetch a pointer to the answer table relating to the proper rounding
# precision.
#
bg_tbl:
	subi.b		&0x30,%d1		# make offset in 0-f range
	tst.b		%d0			# is rmode RN?
	bne.b		bg_not_rn		# no
bg_rn:
	lea.l		BIGRN(%pc),%a0		# yes; load RN table addr
bg_tbl_cont:
	cmpi.b		%d1,&0x1		# is offset <= $31?
	ble.b		set_finx		# yes; answer is inexact
	cmpi.b		%d1,&0x7		# is $32 <= offset <= $37?
	ble.b		no_finx			# yes; answer is exact
	bra.b		set_finx		# no; answer is inexact
bg_not_rn:
	cmpi.b		%d0,&rp_mode		# is rmode RP?
	beq.b		bg_rp			# yes
bg_rzrm:
	lea.l		BIGRZRM(%pc),%a0	# no; load RZ,RM table addr
	bra.b		bg_tbl_cont
bg_rp:
	lea.l		BIGRP(%pc),%a0		# load RP table addr
	bra.b		bg_tbl_cont

# answer is inexact, so set INEX2 and AINEX in the user's FPSR.
set_finx:
	ori.l		&inx2a_mask,USER_FPSR(%a6) # set INEX2/AINEX
no_finx:
	mulu.w		&0xc,%d1		# offset points into tables
	swap		%d0			# put rnd prec in lo word
	tst.b		%d0			# is precision extended?

	bne.b		not_ext			# if xprec, do not call round

# Precision is extended
	fmovm.x		(%a0,%d1.w),&0x80	# return result in fp0
	rts

# Precision is single or double
not_ext:
	swap		%d0			# rnd prec in upper word

# call round() to round the answer to the proper precision.
# exponents out of range for single or double DO NOT cause underflow 
# or overflow.
	mov.w		0x0(%a0,%d1.w),FP_SCR1_EX(%a6) # load first word
	mov.l		0x4(%a0,%d1.w),FP_SCR1_HI(%a6) # load second word
	mov.l		0x8(%a0,%d1.w),FP_SCR1_LO(%a6) # load third word
	mov.l		%d0,%d1
	clr.l		%d0			# clear g,r,s
	lea		FP_SCR1(%a6),%a0	# pass ptr to answer
	clr.w		LOCAL_SGN(%a0)		# sign always positive
	bsr.l		_round			# round the mantissa

	fmovm.x		(%a0),&0x80		# return rounded result in fp0
	rts

	align		0x4

PIRN:	long		0x40000000,0xc90fdaa2,0x2168c235	# pi
PIRZRM:	long		0x40000000,0xc90fdaa2,0x2168c234	# pi
PIRP:	long		0x40000000,0xc90fdaa2,0x2168c235	# pi

SMALRN:	long		0x3ffd0000,0x9a209a84,0xfbcff798	# log10(2)
	long		0x40000000,0xadf85458,0xa2bb4a9a	# e
	long		0x3fff0000,0xb8aa3b29,0x5c17f0bc	# log2(e)
	long		0x3ffd0000,0xde5bd8a9,0x37287195	# log10(e)
	long		0x00000000,0x00000000,0x00000000	# 0.0

SMALRZRM:
	long		0x3ffd0000,0x9a209a84,0xfbcff798	# log10(2)
	long		0x40000000,0xadf85458,0xa2bb4a9a	# e
	long		0x3fff0000,0xb8aa3b29,0x5c17f0bb	# log2(e)
	long		0x3ffd0000,0xde5bd8a9,0x37287195	# log10(e)
	long		0x00000000,0x00000000,0x00000000	# 0.0

SMALRP:	long		0x3ffd0000,0x9a209a84,0xfbcff799	# log10(2)
	long		0x40000000,0xadf85458,0xa2bb4a9b	# e
	long		0x3fff0000,0xb8aa3b29,0x5c17f0bc	# log2(e)
	long		0x3ffd0000,0xde5bd8a9,0x37287195	# log10(e)
	long		0x00000000,0x00000000,0x00000000	# 0.0

BIGRN:	long		0x3ffe0000,0xb17217f7,0xd1cf79ac	# ln(2)
	long		0x40000000,0x935d8ddd,0xaaa8ac17	# ln(10)

	long		0x3fff0000,0x80000000,0x00000000	# 10 ^ 0
	long		0x40020000,0xA0000000,0x00000000	# 10 ^ 1
	long		0x40050000,0xC8000000,0x00000000	# 10 ^ 2
	long		0x400C0000,0x9C400000,0x00000000	# 10 ^ 4
	long		0x40190000,0xBEBC2000,0x00000000	# 10 ^ 8
	long		0x40340000,0x8E1BC9BF,0x04000000	# 10 ^ 16
	long		0x40690000,0x9DC5ADA8,0x2B70B59E	# 10 ^ 32
	long		0x40D30000,0xC2781F49,0xFFCFA6D5	# 10 ^ 64
	long		0x41A80000,0x93BA47C9,0x80E98CE0	# 10 ^ 128
	long		0x43510000,0xAA7EEBFB,0x9DF9DE8E	# 10 ^ 256
	long		0x46A30000,0xE319A0AE,0xA60E91C7	# 10 ^ 512
	long		0x4D480000,0xC9767586,0x81750C17	# 10 ^ 1024
	long		0x5A920000,0x9E8B3B5D,0xC53D5DE5	# 10 ^ 2048
	long		0x75250000,0xC4605202,0x8A20979B	# 10 ^ 4096

BIGRZRM:
	long		0x3ffe0000,0xb17217f7,0xd1cf79ab	# ln(2)
	long		0x40000000,0x935d8ddd,0xaaa8ac16	# ln(10)

	long		0x3fff0000,0x80000000,0x00000000	# 10 ^ 0
	long		0x40020000,0xA0000000,0x00000000	# 10 ^ 1
	long		0x40050000,0xC8000000,0x00000000	# 10 ^ 2
	long		0x400C0000,0x9C400000,0x00000000	# 10 ^ 4
	long		0x40190000,0xBEBC2000,0x00000000	# 10 ^ 8
	long		0x40340000,0x8E1BC9BF,0x04000000	# 10 ^ 16
	long		0x40690000,0x9DC5ADA8,0x2B70B59D	# 10 ^ 32
	long		0x40D30000,0xC2781F49,0xFFCFA6D5	# 10 ^ 64
	long		0x41A80000,0x93BA47C9,0x80E98CDF	# 10 ^ 128
	long		0x43510000,0xAA7EEBFB,0x9DF9DE8D	# 10 ^ 256
	long		0x46A30000,0xE319A0AE,0xA60E91C6	# 10 ^ 512
	long		0x4D480000,0xC9767586,0x81750C17	# 10 ^ 1024
	long		0x5A920000,0x9E8B3B5D,0xC53D5DE4	# 10 ^ 2048
	long		0x75250000,0xC4605202,0x8A20979A	# 10 ^ 4096

BIGRP:
	long		0x3ffe0000,0xb17217f7,0xd1cf79ac	# ln(2)
	long		0x40000000,0x935d8ddd,0xaaa8ac17	# ln(10)

	long		0x3fff0000,0x80000000,0x00000000	# 10 ^ 0
	long		0x40020000,0xA0000000,0x00000000	# 10 ^ 1
	long		0x40050000,0xC8000000,0x00000000	# 10 ^ 2
	long		0x400C0000,0x9C400000,0x00000000	# 10 ^ 4
	long		0x40190000,0xBEBC2000,0x00000000	# 10 ^ 8
	long		0x40340000,0x8E1BC9BF,0x04000000	# 10 ^ 16
	long		0x40690000,0x9DC5ADA8,0x2B70B59E	# 10 ^ 32
	long		0x40D30000,0xC2781F49,0xFFCFA6D6	# 10 ^ 64
	long		0x41A80000,0x93BA47C9,0x80E98CE0	# 10 ^ 128
	long		0x43510000,0xAA7EEBFB,0x9DF9DE8E	# 10 ^ 256
	long		0x46A30000,0xE319A0AE,0xA60E91C7	# 10 ^ 512
	long		0x4D480000,0xC9767586,0x81750C18	# 10 ^ 1024
	long		0x5A920000,0x9E8B3B5D,0xC53D5DE5	# 10 ^ 2048
	long		0x75250000,0xC4605202,0x8A20979B	# 10 ^ 4096

#########################################################################
# sscale(): computes the destination operand scaled by the source	#
#	    operand. If the absoulute value of the source operand is 	#
#	    >= 2^14, an overflow or underflow is returned.		#
#									#
# INPUT *************************************************************** #
#	a0  = pointer to double-extended source operand X		#
#	a1  = pointer to double-extended destination operand Y		#
#									#
# OUTPUT ************************************************************** #
#	fp0 =  scale(X,Y)						#
#									#
#########################################################################

set	SIGN,		L_SCR1

	global		sscale
sscale:
	mov.l		%d0,-(%sp)		# store off ctrl bits for now

	mov.w		DST_EX(%a1),%d1		# get dst exponent
	smi.b		SIGN(%a6)		# use SIGN to hold dst sign
	andi.l		&0x00007fff,%d1		# strip sign from dst exp

	mov.w		SRC_EX(%a0),%d0		# check src bounds
	andi.w		&0x7fff,%d0		# clr src sign bit
	cmpi.w		%d0,&0x3fff		# is src ~ ZERO?
	blt.w		src_small		# yes
	cmpi.w		%d0,&0x400c		# no; is src too big?
	bgt.w		src_out			# yes

#
# Source is within 2^14 range.
#
src_ok:
	fintrz.x	SRC(%a0),%fp0		# calc int of src
	fmov.l		%fp0,%d0		# int src to d0
# don't want any accrued bits from the fintrz showing up later since
# we may need to read the fpsr for the last fp op in t_catch2().
	fmov.l		&0x0,%fpsr

	tst.b		DST_HI(%a1)		# is dst denormalized?
	bmi.b		sok_norm

# the dst is a DENORM. normalize the DENORM and add the adjustment to
# the src value. then, jump to the norm part of the routine.
sok_dnrm:
	mov.l		%d0,-(%sp)		# save src for now

	mov.w		DST_EX(%a1),FP_SCR0_EX(%a6) # make a copy
	mov.l		DST_HI(%a1),FP_SCR0_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR0_LO(%a6)

	lea		FP_SCR0(%a6),%a0	# pass ptr to DENORM
	bsr.l		norm			# normalize the DENORM
	neg.l		%d0
	add.l		(%sp)+,%d0		# add adjustment to src

	fmovm.x		FP_SCR0(%a6),&0x80	# load normalized DENORM

	cmpi.w		%d0,&-0x3fff		# is the shft amt really low?
	bge.b		sok_norm2		# thank goodness no

# the multiply factor that we're trying to create should be a denorm
# for the multiply to work. therefore, we're going to actually do a 
# multiply with a denorm which will cause an unimplemented data type
# exception to be put into the machine which will be caught and corrected
# later. we don't do this with the DENORMs above because this method
# is slower. but, don't fret, I don't see it being used much either.
	fmov.l		(%sp)+,%fpcr		# restore user fpcr
	mov.l		&0x80000000,%d1		# load normalized mantissa
	subi.l		&-0x3fff,%d0		# how many should we shift?
	neg.l		%d0			# make it positive
	cmpi.b		%d0,&0x20		# is it > 32?
	bge.b		sok_dnrm_32		# yes
	lsr.l		%d0,%d1			# no; bit stays in upper lw
	clr.l		-(%sp)			# insert zero low mantissa
	mov.l		%d1,-(%sp)		# insert new high mantissa
	clr.l		-(%sp)			# make zero exponent
	bra.b		sok_norm_cont	
sok_dnrm_32:
	subi.b		&0x20,%d0		# get shift count
	lsr.l		%d0,%d1			# make low mantissa longword
	mov.l		%d1,-(%sp)		# insert new low mantissa
	clr.l		-(%sp)			# insert zero high mantissa
	clr.l		-(%sp)			# make zero exponent
	bra.b		sok_norm_cont
	
# the src will force the dst to a DENORM value or worse. so, let's
# create an fp multiply that will create the result.
sok_norm:
	fmovm.x		DST(%a1),&0x80		# load fp0 with normalized src
sok_norm2:
	fmov.l		(%sp)+,%fpcr		# restore user fpcr

	addi.w		&0x3fff,%d0		# turn src amt into exp value
	swap		%d0			# put exponent in high word
	clr.l		-(%sp)			# insert new exponent
	mov.l		&0x80000000,-(%sp)	# insert new high mantissa
	mov.l		%d0,-(%sp)		# insert new lo mantissa

sok_norm_cont:
	fmov.l		%fpcr,%d0		# d0 needs fpcr for t_catch2
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.x		(%sp)+,%fp0		# do the multiply
	bra		t_catch2		# catch any exceptions

#
# Source is outside of 2^14 range.  Test the sign and branch
# to the appropriate exception handler.
#
src_out:
	mov.l		(%sp)+,%d0		# restore ctrl bits
	exg		%a0,%a1			# swap src,dst ptrs
	tst.b		SRC_EX(%a1)		# is src negative?
	bmi		t_unfl			# yes; underflow
	bra		t_ovfl_sc		# no; overflow

#
# The source input is below 1, so we check for denormalized numbers
# and set unfl.
#
src_small:
	tst.b		DST_HI(%a1)		# is dst denormalized?
	bpl.b		ssmall_done		# yes

	mov.l		(%sp)+,%d0
	fmov.l		%d0,%fpcr		# no; load control bits
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		DST(%a1),%fp0		# simply return dest
	bra		t_catch2
ssmall_done:
	mov.l		(%sp)+,%d0		# load control bits into d1
	mov.l		%a1,%a0			# pass ptr to dst
	bra		t_resdnrm

#########################################################################
# smod(): computes the fp MOD of the input values X,Y.			#
# srem(): computes the fp (IEEE) REM of the input values X,Y.		#
#									#
# INPUT *************************************************************** #
#	a0 = pointer to extended precision input X			#
#	a1 = pointer to extended precision input Y			#
#	d0 = round precision,mode					#
#									#
# 	The input operands X and Y can be either normalized or 		#
#	denormalized.							#
#									#
# OUTPUT ************************************************************** #
#      fp0 = FREM(X,Y) or FMOD(X,Y)					#
#									#
# ALGORITHM *********************************************************** #
#									#
#       Step 1.  Save and strip signs of X and Y: signX := sign(X),	#
#                signY := sign(Y), X := |X|, Y := |Y|, 			#
#                signQ := signX EOR signY. Record whether MOD or REM	#
#                is requested.						#
#									#
#       Step 2.  Set L := expo(X)-expo(Y), k := 0, Q := 0.		#
#                If (L < 0) then					#
#                   R := X, go to Step 4.				#
#                else							#
#                   R := 2^(-L)X, j := L.				#
#                endif							#
#									#
#       Step 3.  Perform MOD(X,Y)					#
#            3.1 If R = Y, go to Step 9.				#
#            3.2 If R > Y, then { R := R - Y, Q := Q + 1}		#
#            3.3 If j = 0, go to Step 4.				#
#            3.4 k := k + 1, j := j - 1, Q := 2Q, R := 2R. Go to	#
#                Step 3.1.						#
#									#
#       Step 4.  At this point, R = X - QY = MOD(X,Y). Set		#
#                Last_Subtract := false (used in Step 7 below). If	#
#                MOD is requested, go to Step 6. 			#
#									#
#       Step 5.  R = MOD(X,Y), but REM(X,Y) is requested.		#
#            5.1 If R < Y/2, then R = MOD(X,Y) = REM(X,Y). Go to	#
#                Step 6.						#
#            5.2 If R > Y/2, then { set Last_Subtract := true,		#
#                Q := Q + 1, Y := signY*Y }. Go to Step 6.		#
#            5.3 This is the tricky case of R = Y/2. If Q is odd,	#
#                then { Q := Q + 1, signX := -signX }.			#
#									#
#       Step 6.  R := signX*R.						#
#									#
#       Step 7.  If Last_Subtract = true, R := R - Y.			#
#									#
#       Step 8.  Return signQ, last 7 bits of Q, and R as required.	#
#									#
#       Step 9.  At this point, R = 2^(-j)*X - Q Y = Y. Thus,		#
#                X = 2^(j)*(Q+1)Y. set Q := 2^(j)*(Q+1),		#
#                R := 0. Return signQ, last 7 bits of Q, and R.		#
#									#
#########################################################################

	set		Mod_Flag,L_SCR3
	set		Sc_Flag,L_SCR3+1

	set		SignY,L_SCR2
	set		SignX,L_SCR2+2
	set		SignQ,L_SCR3+2

	set		Y,FP_SCR0
	set		Y_Hi,Y+4
	set		Y_Lo,Y+8

	set		R,FP_SCR1
	set		R_Hi,R+4
	set		R_Lo,R+8

Scale:
	long		0x00010000,0x80000000,0x00000000,0x00000000

	global		smod
smod:
	clr.b		FPSR_QBYTE(%a6)
	mov.l		%d0,-(%sp)		# save ctrl bits
	clr.b		Mod_Flag(%a6)
	bra.b		Mod_Rem

	global		srem
srem:
	clr.b		FPSR_QBYTE(%a6)
	mov.l		%d0,-(%sp)		# save ctrl bits
	mov.b		&0x1,Mod_Flag(%a6)

Mod_Rem:
#..Save sign of X and Y
	movm.l		&0x3f00,-(%sp)		# save data registers
	mov.w		SRC_EX(%a0),%d3
	mov.w		%d3,SignY(%a6)
	and.l		&0x00007FFF,%d3		# Y := |Y|

#
	mov.l		SRC_HI(%a0),%d4
	mov.l		SRC_LO(%a0),%d5		# (D3,D4,D5) is |Y|

	tst.l		%d3
	bne.b		Y_Normal

	mov.l		&0x00003FFE,%d3		# $3FFD + 1
	tst.l		%d4
	bne.b		HiY_not0

HiY_0:
	mov.l		%d5,%d4
	clr.l		%d5
	sub.l		&32,%d3
	clr.l		%d6
	bfffo		%d4{&0:&32},%d6
	lsl.l		%d6,%d4
	sub.l		%d6,%d3			# (D3,D4,D5) is normalized
#	                                        ...with bias $7FFD
	bra.b		Chk_X

HiY_not0:
	clr.l		%d6
	bfffo		%d4{&0:&32},%d6
	sub.l		%d6,%d3
	lsl.l		%d6,%d4
	mov.l		%d5,%d7			# a copy of D5
	lsl.l		%d6,%d5
	neg.l		%d6
	add.l		&32,%d6
	lsr.l		%d6,%d7
	or.l		%d7,%d4			# (D3,D4,D5) normalized
#                                       ...with bias $7FFD
	bra.b		Chk_X

Y_Normal:
	add.l		&0x00003FFE,%d3		# (D3,D4,D5) normalized
#                                       ...with bias $7FFD

Chk_X:
	mov.w		DST_EX(%a1),%d0
	mov.w		%d0,SignX(%a6)
	mov.w		SignY(%a6),%d1
	eor.l		%d0,%d1
	and.l		&0x00008000,%d1
	mov.w		%d1,SignQ(%a6)		# sign(Q) obtained
	and.l		&0x00007FFF,%d0
	mov.l		DST_HI(%a1),%d1
	mov.l		DST_LO(%a1),%d2		# (D0,D1,D2) is |X|
	tst.l		%d0
	bne.b		X_Normal
	mov.l		&0x00003FFE,%d0
	tst.l		%d1
	bne.b		HiX_not0

HiX_0:
	mov.l		%d2,%d1
	clr.l		%d2
	sub.l		&32,%d0
	clr.l		%d6
	bfffo		%d1{&0:&32},%d6
	lsl.l		%d6,%d1
	sub.l		%d6,%d0			# (D0,D1,D2) is normalized
#                                       ...with bias $7FFD
	bra.b		Init

HiX_not0:
	clr.l		%d6
	bfffo		%d1{&0:&32},%d6
	sub.l		%d6,%d0
	lsl.l		%d6,%d1
	mov.l		%d2,%d7			# a copy of D2
	lsl.l		%d6,%d2
	neg.l		%d6
	add.l		&32,%d6
	lsr.l		%d6,%d7
	or.l		%d7,%d1			# (D0,D1,D2) normalized
#                                       ...with bias $7FFD
	bra.b		Init

X_Normal:
	add.l		&0x00003FFE,%d0		# (D0,D1,D2) normalized
#                                       ...with bias $7FFD

Init:
#
	mov.l		%d3,L_SCR1(%a6)		# save biased exp(Y)
	mov.l		%d0,-(%sp)		# save biased exp(X)
	sub.l		%d3,%d0			# L := expo(X)-expo(Y)

	clr.l		%d6			# D6 := carry <- 0
	clr.l		%d3			# D3 is Q
	mov.l		&0,%a1			# A1 is k; j+k=L, Q=0

#..(Carry,D1,D2) is R
	tst.l		%d0
	bge.b		Mod_Loop_pre

#..expo(X) < expo(Y). Thus X = mod(X,Y)
#
	mov.l		(%sp)+,%d0		# restore d0
	bra.w		Get_Mod

Mod_Loop_pre:
	addq.l		&0x4,%sp		# erase exp(X)
#..At this point  R = 2^(-L)X; Q = 0; k = 0; and  k+j = L
Mod_Loop:
	tst.l		%d6			# test carry bit
	bgt.b		R_GT_Y

#..At this point carry = 0, R = (D1,D2), Y = (D4,D5)
	cmp.l		%d1,%d4			# compare hi(R) and hi(Y)
	bne.b		R_NE_Y
	cmp.l		%d2,%d5			# compare lo(R) and lo(Y)
	bne.b		R_NE_Y

#..At this point, R = Y
	bra.w		Rem_is_0

R_NE_Y:
#..use the borrow of the previous compare
	bcs.b		R_LT_Y			# borrow is set iff R < Y

R_GT_Y:
#..If Carry is set, then Y < (Carry,D1,D2) < 2Y. Otherwise, Carry = 0
#..and Y < (D1,D2) < 2Y. Either way, perform R - Y
	sub.l		%d5,%d2			# lo(R) - lo(Y)
	subx.l		%d4,%d1			# hi(R) - hi(Y)
	clr.l		%d6			# clear carry
	addq.l		&1,%d3			# Q := Q + 1

R_LT_Y:
#..At this point, Carry=0, R < Y. R = 2^(k-L)X - QY; k+j = L; j >= 0.
	tst.l		%d0			# see if j = 0.
	beq.b		PostLoop

	add.l		%d3,%d3			# Q := 2Q
	add.l		%d2,%d2			# lo(R) = 2lo(R)
	roxl.l		&1,%d1			# hi(R) = 2hi(R) + carry
	scs		%d6			# set Carry if 2(R) overflows
	addq.l		&1,%a1			# k := k+1
	subq.l		&1,%d0			# j := j - 1
#..At this point, R=(Carry,D1,D2) = 2^(k-L)X - QY, j+k=L, j >= 0, R < 2Y.

	bra.b		Mod_Loop

PostLoop:
#..k = L, j = 0, Carry = 0, R = (D1,D2) = X - QY, R < Y.

#..normalize R.
	mov.l		L_SCR1(%a6),%d0		# new biased expo of R
	tst.l		%d1
	bne.b		HiR_not0

HiR_0:
	mov.l		%d2,%d1
	clr.l		%d2
	sub.l		&32,%d0
	clr.l		%d6
	bfffo		%d1{&0:&32},%d6
	lsl.l		%d6,%d1
	sub.l		%d6,%d0			# (D0,D1,D2) is normalized
#                                       ...with bias $7FFD
	bra.b		Get_Mod

HiR_not0:
	clr.l		%d6
	bfffo		%d1{&0:&32},%d6
	bmi.b		Get_Mod			# already normalized
	sub.l		%d6,%d0
	lsl.l		%d6,%d1
	mov.l		%d2,%d7			# a copy of D2
	lsl.l		%d6,%d2
	neg.l		%d6
	add.l		&32,%d6
	lsr.l		%d6,%d7
	or.l		%d7,%d1			# (D0,D1,D2) normalized

#
Get_Mod:
	cmp.l		%d0,&0x000041FE
	bge.b		No_Scale
Do_Scale:
	mov.w		%d0,R(%a6)
	mov.l		%d1,R_Hi(%a6)
	mov.l		%d2,R_Lo(%a6)
	mov.l		L_SCR1(%a6),%d6
	mov.w		%d6,Y(%a6)
	mov.l		%d4,Y_Hi(%a6)
	mov.l		%d5,Y_Lo(%a6)
	fmov.x		R(%a6),%fp0		# no exception
	mov.b		&1,Sc_Flag(%a6)
	bra.b		ModOrRem
No_Scale:
	mov.l		%d1,R_Hi(%a6)
	mov.l		%d2,R_Lo(%a6)
	sub.l		&0x3FFE,%d0
	mov.w		%d0,R(%a6)
	mov.l		L_SCR1(%a6),%d6
	sub.l		&0x3FFE,%d6
	mov.l		%d6,L_SCR1(%a6)
	fmov.x		R(%a6),%fp0
	mov.w		%d6,Y(%a6)
	mov.l		%d4,Y_Hi(%a6)
	mov.l		%d5,Y_Lo(%a6)
	clr.b		Sc_Flag(%a6)

#
ModOrRem:
	tst.b		Mod_Flag(%a6)
	beq.b		Fix_Sign

	mov.l		L_SCR1(%a6),%d6		# new biased expo(Y)
	subq.l		&1,%d6			# biased expo(Y/2)
	cmp.l		%d0,%d6
	blt.b		Fix_Sign
	bgt.b		Last_Sub

	cmp.l		%d1,%d4
	bne.b		Not_EQ
	cmp.l		%d2,%d5
	bne.b		Not_EQ
	bra.w		Tie_Case

Not_EQ:
	bcs.b		Fix_Sign

Last_Sub:
#
	fsub.x		Y(%a6),%fp0		# no exceptions
	addq.l		&1,%d3			# Q := Q + 1

#
Fix_Sign:
#..Get sign of X
	mov.w		SignX(%a6),%d6
	bge.b		Get_Q
	fneg.x		%fp0

#..Get Q
#
Get_Q:
	clr.l		%d6
	mov.w		SignQ(%a6),%d6		# D6 is sign(Q)
	mov.l		&8,%d7
	lsr.l		%d7,%d6
	and.l		&0x0000007F,%d3		# 7 bits of Q
	or.l		%d6,%d3			# sign and bits of Q
#	swap		%d3
#	fmov.l		%fpsr,%d6
#	and.l		&0xFF00FFFF,%d6
#	or.l		%d3,%d6
#	fmov.l		%d6,%fpsr		# put Q in fpsr
	mov.b		%d3,FPSR_QBYTE(%a6)	# put Q in fpsr

#
Restore:
	movm.l		(%sp)+,&0xfc		#  {%d2-%d7}
	mov.l		(%sp)+,%d0
	fmov.l		%d0,%fpcr
	tst.b		Sc_Flag(%a6)
	beq.b		Finish
	mov.b		&FMUL_OP,%d1		# last inst is MUL
	fmul.x		Scale(%pc),%fp0		# may cause underflow
	bra		t_catch2
# the '040 package did this apparently to see if the dst operand for the 
# preceding fmul was a denorm. but, it better not have been since the 
# algorithm just got done playing with fp0 and expected no exceptions
# as a result. trust me...
#	bra		t_avoid_unsupp		# check for denorm as a
#						;result of the scaling

Finish:
	mov.b		&FMOV_OP,%d1		# last inst is MOVE
	fmov.x		%fp0,%fp0		# capture exceptions & round
	bra		t_catch2

Rem_is_0:
#..R = 2^(-j)X - Q Y = Y, thus R = 0 and quotient = 2^j (Q+1)
	addq.l		&1,%d3
	cmp.l		%d0,&8			# D0 is j 
	bge.b		Q_Big

	lsl.l		%d0,%d3
	bra.b		Set_R_0

Q_Big:
	clr.l		%d3

Set_R_0:
	fmov.s		&0x00000000,%fp0
	clr.b		Sc_Flag(%a6)
	bra.w		Fix_Sign

Tie_Case:
#..Check parity of Q
	mov.l		%d3,%d6
	and.l		&0x00000001,%d6
	tst.l		%d6
	beq.w		Fix_Sign		# Q is even

#..Q is odd, Q := Q + 1, signX := -signX
	addq.l		&1,%d3
	mov.w		SignX(%a6),%d6
	eor.l		&0x00008000,%d6
	mov.w		%d6,SignX(%a6)
	bra.w		Fix_Sign

qnan:	long		0x7fff0000, 0xffffffff, 0xffffffff

#########################################################################
# XDEF ****************************************************************	#
#	t_dz(): Handle DZ exception during transcendental emulation.	#
#	        Sets N bit according to sign of source operand.		#
#	t_dz2(): Handle DZ exception during transcendental emulation.	#
#		 Sets N bit always.					#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to source operand					#
# 									#
# OUTPUT **************************************************************	#
#	fp0 = default result						#
#									#
# ALGORITHM ***********************************************************	#
#	- Store properly signed INF into fp0.				#
#	- Set FPSR exception status dz bit, ccode inf bit, and 		#
#	  accrued dz bit.						#
#									#
#########################################################################

	global		t_dz
t_dz:
	tst.b		SRC_EX(%a0) 		# no; is src negative?
	bmi.b		t_dz2			# yes

dz_pinf:
	fmov.s		&0x7f800000,%fp0	# return +INF in fp0
	ori.l		&dzinf_mask,USER_FPSR(%a6) # set I/DZ/ADZ
	rts

	global		t_dz2
t_dz2:
	fmov.s		&0xff800000,%fp0	# return -INF in fp0
	ori.l		&dzinf_mask+neg_mask,USER_FPSR(%a6) # set N/I/DZ/ADZ
	rts

#################################################################
# OPERR exception:						#
#	- set FPSR exception status operr bit, condition code 	#
#	  nan bit; Store default NAN into fp0			#
#################################################################
	global		t_operr
t_operr:
	ori.l		&opnan_mask,USER_FPSR(%a6) # set NaN/OPERR/AIOP
	fmovm.x		qnan(%pc),&0x80		# return default NAN in fp0
	rts

#################################################################
# Extended DENORM:						#
# 	- For all functions that have a denormalized input and	#
#	  that f(x)=x, this is the entry point.			#
#	- we only return the EXOP here if either underflow or	#
#	  inexact is enabled.					#
#################################################################

# Entry point for scale w/ extended denorm. The function does
# NOT set INEX2/AUNFL/AINEX.
	global		t_resdnrm
t_resdnrm:
	ori.l		&unfl_mask,USER_FPSR(%a6) # set UNFL
	bra.b		xdnrm_con

	global		t_extdnrm
t_extdnrm:
	ori.l		&unfinx_mask,USER_FPSR(%a6) # set UNFL/INEX2/AUNFL/AINEX

xdnrm_con:
	mov.l		%a0,%a1			# make copy of src ptr
	mov.l		%d0,%d1			# make copy of rnd prec,mode
	andi.b		&0xc0,%d1		# extended precision?
	bne.b		xdnrm_sd		# no

# result precision is extended.
	tst.b		LOCAL_EX(%a0)		# is denorm negative?
	bpl.b		xdnrm_exit		# no

	bset		&neg_bit,FPSR_CC(%a6)	# yes; set 'N' ccode bit
	bra.b		xdnrm_exit

# result precision is single or double
xdnrm_sd:
	mov.l		%a1,-(%sp)
	tst.b		LOCAL_EX(%a0)		# is denorm pos or neg?
	smi.b		%d1			# set d0 accodingly
	bsr.l		unf_sub
	mov.l		(%sp)+,%a1
xdnrm_exit:
	fmovm.x		(%a0),&0x80		# return default result in fp0

	mov.b		FPCR_ENABLE(%a6),%d0
	andi.b		&0x0a,%d0		# is UNFL or INEX enabled?
	bne.b		xdnrm_ena		# yes
	rts

################
# unfl enabled #
################
# we have a DENORM that needs to be converted into an EXOP.
# so, normalize the mantissa, add 0x6000 to the new exponent,
# and return the result in fp1.
xdnrm_ena:
	mov.w		LOCAL_EX(%a1),FP_SCR0_EX(%a6)
	mov.l		LOCAL_HI(%a1),FP_SCR0_HI(%a6)
	mov.l		LOCAL_LO(%a1),FP_SCR0_LO(%a6)

	lea		FP_SCR0(%a6),%a0
	bsr.l		norm			# normalize mantissa
	addi.l		&0x6000,%d0		# add extra bias
	andi.w		&0x8000,FP_SCR0_EX(%a6)	# keep old sign
	or.w		%d0,FP_SCR0_EX(%a6)	# insert new exponent

	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	rts

#################################################################
# UNFL exception:						#
# 	- This routine is for cases where even an EXOP isn't	#
#  	  large enough to hold the range of this result.	#
#	  In such a case, the EXOP equals zero.			#
#  	- Return the default result to the proper precision 	#
#	  with the sign of this result being the same as that	#
#	  of the src operand.					#
# 	- t_unfl2() is provided to force the result sign to 	#
#	  positive which is the desired result for fetox().	#
#################################################################
	global		t_unfl
t_unfl:
	ori.l		&unfinx_mask,USER_FPSR(%a6) # set UNFL/INEX2/AUNFL/AINEX

	tst.b		(%a0)			# is result pos or neg?
	smi.b		%d1			# set d1 accordingly
	bsr.l		unf_sub			# calc default unfl result
	fmovm.x		(%a0),&0x80		# return default result in fp0

	fmov.s		&0x00000000,%fp1	# return EXOP in fp1
	rts

# t_unfl2 ALWAYS tells unf_sub to create a positive result
	global		t_unfl2
t_unfl2:
	ori.l		&unfinx_mask,USER_FPSR(%a6) # set UNFL/INEX2/AUNFL/AINEX

	sf.b		%d1			# set d0 to represent positive
	bsr.l		unf_sub			# calc default unfl result
	fmovm.x		(%a0),&0x80		# return default result in fp0

	fmov.s		&0x0000000,%fp1		# return EXOP in fp1
	rts

#################################################################
# OVFL exception:						#
# 	- This routine is for cases where even an EXOP isn't	#
#  	  large enough to hold the range of this result.	#
# 	- Return the default result to the proper precision 	#
#	  with the sign of this result being the same as that 	#
#	  of the src operand.					#
# 	- t_ovfl2() is provided to force the result sign to 	#
#	  positive which is the desired result for fcosh().	#
# 	- t_ovfl_sc() is provided for scale() which only sets 	#
#	  the inexact bits if the number is inexact for the 	#
#	  precision indicated.					#
#################################################################

	global		t_ovfl_sc
t_ovfl_sc:
	ori.l		&ovfl_inx_mask,USER_FPSR(%a6) # set OVFL/AOVFL/AINEX

	mov.b		%d0,%d1			# fetch rnd mode/prec
	andi.b		&0xc0,%d1		# extract rnd prec
	beq.b		ovfl_work		# prec is extended

	tst.b		LOCAL_HI(%a0)		# is dst a DENORM?
	bmi.b		ovfl_sc_norm		# no

# dst op is a DENORM. we have to normalize the mantissa to see if the
# result would be inexact for the given precision. make a copy of the
# dst so we don't screw up the version passed to us.
	mov.w		LOCAL_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		LOCAL_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		LOCAL_LO(%a0),FP_SCR0_LO(%a6)
	lea		FP_SCR0(%a6),%a0	# pass ptr to FP_SCR0
	movm.l		&0xc080,-(%sp)		# save d0-d1/a0
	bsr.l		norm			# normalize mantissa
	movm.l		(%sp)+,&0x0103		# restore d0-d1/a0

ovfl_sc_norm:
	cmpi.b		%d1,&0x40		# is prec dbl?
	bne.b		ovfl_sc_dbl		# no; sgl
ovfl_sc_sgl:
	tst.l		LOCAL_LO(%a0)		# is lo lw of sgl set?
	bne.b		ovfl_sc_inx		# yes
	tst.b		3+LOCAL_HI(%a0)		# is lo byte of hi lw set?
	bne.b		ovfl_sc_inx		# yes
	bra.b		ovfl_work		# don't set INEX2
ovfl_sc_dbl:
	mov.l		LOCAL_LO(%a0),%d1	# are any of lo 11 bits of
	andi.l		&0x7ff,%d1		# dbl mantissa set?
	beq.b		ovfl_work		# no; don't set INEX2
ovfl_sc_inx:
	ori.l		&inex2_mask,USER_FPSR(%a6) # set INEX2
	bra.b		ovfl_work		# continue

	global		t_ovfl
t_ovfl:
	ori.l		&ovfinx_mask,USER_FPSR(%a6) # set OVFL/INEX2/AOVFL/AINEX

ovfl_work:
	tst.b		LOCAL_EX(%a0)		# what is the sign?
	smi.b		%d1			# set d1 accordingly
	bsr.l		ovf_res			# calc default ovfl result
	mov.b		%d0,FPSR_CC(%a6)	# insert new ccodes
	fmovm.x		(%a0),&0x80		# return default result in fp0

	fmov.s		&0x00000000,%fp1	# return EXOP in fp1
	rts

# t_ovfl2 ALWAYS tells ovf_res to create a positive result
	global		t_ovfl2
t_ovfl2:
	ori.l		&ovfinx_mask,USER_FPSR(%a6) # set OVFL/INEX2/AOVFL/AINEX

	sf.b		%d1			# clear sign flag for positive
	bsr.l		ovf_res			# calc default ovfl result
	mov.b		%d0,FPSR_CC(%a6)	# insert new ccodes
	fmovm.x		(%a0),&0x80		# return default result in fp0

	fmov.s		&0x00000000,%fp1	# return EXOP in fp1
	rts

#################################################################
# t_catch(): 							#
#	- the last operation of a transcendental emulation	#
# 	  routine may have caused an underflow or overflow. 	#
# 	  we find out if this occurred by doing an fsave and 	#
#	  checking the exception bit. if one did occur, then we	#
#	  jump to fgen_except() which creates the default	#
#	  result and EXOP for us.				#
#################################################################
	global		t_catch
t_catch:

	fsave		-(%sp)
	tst.b		0x2(%sp)
	bmi.b		catch
	add.l		&0xc,%sp

#################################################################
# INEX2 exception:						#
#	- The inex2 and ainex bits are set.			#
#################################################################
	global		t_inx2
t_inx2:
	fblt.w		t_minx2
	fbeq.w		inx2_zero

	global		t_pinx2
t_pinx2:
	ori.w		&inx2a_mask,2+USER_FPSR(%a6) # set INEX2/AINEX
	rts

	global		t_minx2
t_minx2:
	ori.l		&inx2a_mask+neg_mask,USER_FPSR(%a6) # set N/INEX2/AINEX
	rts

inx2_zero:
	mov.b		&z_bmask,FPSR_CC(%a6)
	ori.w		&inx2a_mask,2+USER_FPSR(%a6) # set INEX2/AINEX
	rts

# an underflow or overflow exception occurred.
# we must set INEX/AINEX since the fmul/fdiv/fmov emulation may not!
catch:
	ori.w		&inx2a_mask,FPSR_EXCEPT(%a6)
catch2:
	bsr.l		fgen_except
	add.l		&0xc,%sp
	rts

	global		t_catch2
t_catch2:

	fsave		-(%sp)

	tst.b		0x2(%sp)
	bmi.b		catch2
	add.l		&0xc,%sp

	fmov.l		%fpsr,%d0
	or.l		%d0,USER_FPSR(%a6)

	rts

#########################################################################

#########################################################################
# unf_res(): underflow default result calculation for transcendentals	#
#									#
# INPUT:								#
# 	d0   : rnd mode,precision					#
# 	d1.b : sign bit of result ('11111111 = (-) ; '00000000 = (+))	#
# OUTPUT:								#
#	a0   : points to result (in instruction memory)			#
#########################################################################
unf_sub:
	ori.l		&unfinx_mask,USER_FPSR(%a6)

	andi.w		&0x10,%d1		# keep sign bit in 4th spot

	lsr.b		&0x4,%d0		# shift rnd prec,mode to lo bits
	andi.b		&0xf,%d0		# strip hi rnd mode bit
	or.b		%d1,%d0			# concat {sgn,mode,prec}

	mov.l		%d0,%d1			# make a copy
	lsl.b		&0x1,%d1		# mult index 2 by 2

	mov.b		(tbl_unf_cc.b,%pc,%d0.w*1),FPSR_CC(%a6) # insert ccode bits
	lea		(tbl_unf_result.b,%pc,%d1.w*8),%a0 # grab result ptr
	rts

tbl_unf_cc:
	byte		0x4, 0x4, 0x4, 0x0
	byte		0x4, 0x4, 0x4, 0x0
	byte		0x4, 0x4, 0x4, 0x0
	byte		0x0, 0x0, 0x0, 0x0
	byte		0x8+0x4, 0x8+0x4, 0x8, 0x8+0x4
	byte		0x8+0x4, 0x8+0x4, 0x8, 0x8+0x4
	byte		0x8+0x4, 0x8+0x4, 0x8, 0x8+0x4

tbl_unf_result:
	long		0x00000000, 0x00000000, 0x00000000, 0x0 # ZERO;ext
	long		0x00000000, 0x00000000, 0x00000000, 0x0 # ZERO;ext
	long		0x00000000, 0x00000000, 0x00000000, 0x0 # ZERO;ext
	long		0x00000000, 0x00000000, 0x00000001, 0x0 # MIN; ext

	long		0x3f810000, 0x00000000, 0x00000000, 0x0 # ZERO;sgl
	long		0x3f810000, 0x00000000, 0x00000000, 0x0 # ZERO;sgl
	long		0x3f810000, 0x00000000, 0x00000000, 0x0 # ZERO;sgl
	long		0x3f810000, 0x00000100, 0x00000000, 0x0 # MIN; sgl

	long		0x3c010000, 0x00000000, 0x00000000, 0x0 # ZERO;dbl
	long		0x3c010000, 0x00000000, 0x00000000, 0x0 # ZER0;dbl
	long		0x3c010000, 0x00000000, 0x00000000, 0x0 # ZERO;dbl
	long		0x3c010000, 0x00000000, 0x00000800, 0x0 # MIN; dbl

	long		0x0,0x0,0x0,0x0
	long		0x0,0x0,0x0,0x0
	long		0x0,0x0,0x0,0x0
	long		0x0,0x0,0x0,0x0
	
	long		0x80000000, 0x00000000, 0x00000000, 0x0 # ZERO;ext
	long		0x80000000, 0x00000000, 0x00000000, 0x0 # ZERO;ext
	long		0x80000000, 0x00000000, 0x00000001, 0x0 # MIN; ext
	long		0x80000000, 0x00000000, 0x00000000, 0x0 # ZERO;ext

	long		0xbf810000, 0x00000000, 0x00000000, 0x0 # ZERO;sgl
	long		0xbf810000, 0x00000000, 0x00000000, 0x0 # ZERO;sgl
	long		0xbf810000, 0x00000100, 0x00000000, 0x0 # MIN; sgl
	long		0xbf810000, 0x00000000, 0x00000000, 0x0 # ZERO;sgl

	long		0xbc010000, 0x00000000, 0x00000000, 0x0 # ZERO;dbl
	long		0xbc010000, 0x00000000, 0x00000000, 0x0 # ZERO;dbl
	long		0xbc010000, 0x00000000, 0x00000800, 0x0 # MIN; dbl
	long		0xbc010000, 0x00000000, 0x00000000, 0x0 # ZERO;dbl

############################################################

#########################################################################
# src_zero(): Return signed zero according to sign of src operand.	#
#########################################################################
	global		src_zero
src_zero:
	tst.b		SRC_EX(%a0)		# get sign of src operand
	bmi.b		ld_mzero		# if neg, load neg zero

#
# ld_pzero(): return a positive zero.
#
	global		ld_pzero
ld_pzero:
	fmov.s		&0x00000000,%fp0	# load +0
	mov.b		&z_bmask,FPSR_CC(%a6)	# set 'Z' ccode bit
	rts

# ld_mzero(): return a negative zero.
	global		ld_mzero
ld_mzero:
	fmov.s		&0x80000000,%fp0	# load -0
	mov.b		&neg_bmask+z_bmask,FPSR_CC(%a6) # set 'N','Z' ccode bits
	rts

#########################################################################
# dst_zero(): Return signed zero according to sign of dst operand.	#
#########################################################################
	global		dst_zero
dst_zero:
	tst.b		DST_EX(%a1) 		# get sign of dst operand
	bmi.b		ld_mzero		# if neg, load neg zero
	bra.b		ld_pzero		# load positive zero

#########################################################################
# src_inf(): Return signed inf according to sign of src operand.	#
#########################################################################
	global		src_inf
src_inf:
	tst.b		SRC_EX(%a0) 		# get sign of src operand
	bmi.b		ld_minf			# if negative branch

#
# ld_pinf(): return a positive infinity.
#
	global		ld_pinf
ld_pinf:
	fmov.s		&0x7f800000,%fp0	# load +INF
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set 'INF' ccode bit
	rts

#
# ld_minf():return a negative infinity.
#
	global		ld_minf
ld_minf:
	fmov.s		&0xff800000,%fp0	# load -INF
	mov.b		&neg_bmask+inf_bmask,FPSR_CC(%a6) # set 'N','I' ccode bits
	rts

#########################################################################
# dst_inf(): Return signed inf according to sign of dst operand.	#
#########################################################################
	global		dst_inf
dst_inf:
	tst.b		DST_EX(%a1) 		# get sign of dst operand
	bmi.b		ld_minf			# if negative branch
	bra.b		ld_pinf

	global		szr_inf
#################################################################
# szr_inf(): Return +ZERO for a negative src operand or		#
#	            +INF for a positive src operand.		#
#	     Routine used for fetox, ftwotox, and ftentox.	#
#################################################################
szr_inf:
	tst.b		SRC_EX(%a0)		# check sign of source
	bmi.b		ld_pzero
	bra.b		ld_pinf

#########################################################################
# sopr_inf(): Return +INF for a positive src operand or			#
#	      jump to operand error routine for a negative src operand.	#
#	      Routine used for flogn, flognp1, flog10, and flog2.	#
#########################################################################
	global		sopr_inf
sopr_inf:
	tst.b		SRC_EX(%a0)		# check sign of source
	bmi.w		t_operr
	bra.b		ld_pinf

#################################################################
# setoxm1i(): Return minus one for a negative src operand or	#
#	      positive infinity for a positive src operand.	#
#	      Routine used for fetoxm1.				#
#################################################################
	global		setoxm1i
setoxm1i:
	tst.b		SRC_EX(%a0)		# check sign of source
	bmi.b		ld_mone
	bra.b		ld_pinf

#########################################################################
# src_one(): Return signed one according to sign of src operand.	#
#########################################################################
	global		src_one
src_one:
	tst.b		SRC_EX(%a0) 		# check sign of source
	bmi.b		ld_mone

#
# ld_pone(): return positive one.
#
	global		ld_pone
ld_pone:
	fmov.s		&0x3f800000,%fp0	# load +1
	clr.b		FPSR_CC(%a6)
	rts

#
# ld_mone(): return negative one.
#
	global		ld_mone
ld_mone:
	fmov.s		&0xbf800000,%fp0	# load -1
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
	rts

ppiby2:	long		0x3fff0000, 0xc90fdaa2, 0x2168c235
mpiby2:	long		0xbfff0000, 0xc90fdaa2, 0x2168c235

#################################################################
# spi_2(): Return signed PI/2 according to sign of src operand.	#
#################################################################
	global		spi_2
spi_2:
	tst.b		SRC_EX(%a0) 		# check sign of source
	bmi.b		ld_mpi2

#
# ld_ppi2(): return positive PI/2.
#
	global		ld_ppi2
ld_ppi2:
	fmov.l		%d0,%fpcr
	fmov.x		ppiby2(%pc),%fp0	# load +pi/2
	bra.w		t_pinx2			# set INEX2

#
# ld_mpi2(): return negative PI/2.
#
	global		ld_mpi2
ld_mpi2:
	fmov.l		%d0,%fpcr
	fmov.x		mpiby2(%pc),%fp0	# load -pi/2
	bra.w		t_minx2			# set INEX2

####################################################
# The following routines give support for fsincos. #
####################################################

#
# ssincosz(): When the src operand is ZERO, store a one in the
# 	      cosine register and return a ZERO in fp0 w/ the same sign
#	      as the src operand.
#
	global		ssincosz
ssincosz:
	fmov.s		&0x3f800000,%fp1
	tst.b		SRC_EX(%a0)		# test sign
	bpl.b		sincoszp
	fmov.s		&0x80000000,%fp0	# return sin result in fp0
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6)
	bra.b		sto_cos			# store cosine result
sincoszp:
	fmov.s		&0x00000000,%fp0	# return sin result in fp0
	mov.b		&z_bmask,FPSR_CC(%a6)
	bra.b		sto_cos			# store cosine result

#
# ssincosi(): When the src operand is INF, store a QNAN in the cosine
#	      register and jump to the operand error routine for negative
#	      src operands.
#
	global		ssincosi
ssincosi:
	fmov.x		qnan(%pc),%fp1		# load NAN
	bsr.l		sto_cos			# store cosine result
	bra.w		t_operr

#
# ssincosqnan(): When the src operand is a QNAN, store the QNAN in the cosine
# 		 register and branch to the src QNAN routine.
#
	global		ssincosqnan
ssincosqnan:
	fmov.x		LOCAL_EX(%a0),%fp1
	bsr.l		sto_cos
	bra.w		src_qnan

#
# ssincossnan(): When the src operand is an SNAN, store the SNAN w/ the SNAN bit set
#		 in the cosine register and branch to the src SNAN routine.
#
	global		ssincossnan
ssincossnan:
	fmov.x		LOCAL_EX(%a0),%fp1
	bsr.l		sto_cos
	bra.w		src_snan

########################################################################

#########################################################################
# sto_cos(): store fp1 to the fpreg designated by the CMDREG dst field.	#
#	     fp1 holds the result of the cosine portion of ssincos().	#
#	     the value in fp1 will not take any exceptions when moved.	#
# INPUT:								#
#	fp1 : fp value to store						#
# MODIFIED:								#
#	d0								#
#########################################################################
	global		sto_cos
sto_cos:
	mov.b		1+EXC_CMDREG(%a6),%d0
	andi.w		&0x7,%d0
	mov.w		(tbl_sto_cos.b,%pc,%d0.w*2),%d0
	jmp		(tbl_sto_cos.b,%pc,%d0.w*1)

tbl_sto_cos:
	short		sto_cos_0 - tbl_sto_cos
	short		sto_cos_1 - tbl_sto_cos
	short		sto_cos_2 - tbl_sto_cos
	short		sto_cos_3 - tbl_sto_cos
	short		sto_cos_4 - tbl_sto_cos
	short		sto_cos_5 - tbl_sto_cos
	short		sto_cos_6 - tbl_sto_cos
	short		sto_cos_7 - tbl_sto_cos

sto_cos_0:
	fmovm.x		&0x40,EXC_FP0(%a6)
	rts
sto_cos_1:
	fmovm.x		&0x40,EXC_FP1(%a6)
	rts
sto_cos_2:
	fmov.x 		%fp1,%fp2
	rts
sto_cos_3:
	fmov.x		%fp1,%fp3
	rts
sto_cos_4:
	fmov.x		%fp1,%fp4
	rts
sto_cos_5:
	fmov.x		%fp1,%fp5
	rts
sto_cos_6:
	fmov.x		%fp1,%fp6
	rts
sto_cos_7:
	fmov.x		%fp1,%fp7
	rts

##################################################################
	global		smod_sdnrm
	global		smod_snorm
smod_sdnrm:
smod_snorm:
	mov.b		DTAG(%a6),%d1
	beq.l		smod
	cmpi.b		%d1,&ZERO
	beq.w		smod_zro
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		smod
	cmpi.b		%d1,&SNAN
	beq.l		dst_snan
	bra.l		dst_qnan

	global		smod_szero
smod_szero:
	mov.b		DTAG(%a6),%d1
	beq.l		t_operr
	cmpi.b		%d1,&ZERO
	beq.l		t_operr
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		t_operr
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	bra.l		dst_snan

	global		smod_sinf
smod_sinf:
	mov.b		DTAG(%a6),%d1
	beq.l		smod_fpn
	cmpi.b		%d1,&ZERO
	beq.l		smod_zro
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		smod_fpn
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	bra.l		dst_snan

smod_zro:
srem_zro:
	mov.b		SRC_EX(%a0),%d1		# get src sign
	mov.b		DST_EX(%a1),%d0		# get dst sign
	eor.b		%d0,%d1			# get qbyte sign
	andi.b		&0x80,%d1
	mov.b		%d1,FPSR_QBYTE(%a6)
	tst.b		%d0
	bpl.w		ld_pzero
	bra.w		ld_mzero

smod_fpn:
srem_fpn:
	clr.b		FPSR_QBYTE(%a6)
	mov.l		%d0,-(%sp)
	mov.b		SRC_EX(%a0),%d1		# get src sign
	mov.b		DST_EX(%a1),%d0		# get dst sign
	eor.b		%d0,%d1			# get qbyte sign
	andi.b		&0x80,%d1
	mov.b		%d1,FPSR_QBYTE(%a6)
	cmpi.b		DTAG(%a6),&DENORM
	bne.b		smod_nrm
	lea		DST(%a1),%a0
	mov.l		(%sp)+,%d0
	bra		t_resdnrm
smod_nrm:
	fmov.l		(%sp)+,%fpcr
	fmov.x		DST(%a1),%fp0
	tst.b		DST_EX(%a1)
	bmi.b		smod_nrm_neg
	rts

smod_nrm_neg:
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode
	rts

#########################################################################
	global		srem_snorm
	global		srem_sdnrm
srem_sdnrm:
srem_snorm:
	mov.b		DTAG(%a6),%d1
	beq.l		srem
	cmpi.b		%d1,&ZERO
	beq.w		srem_zro
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		srem
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	bra.l		dst_snan

	global		srem_szero
srem_szero:
	mov.b		DTAG(%a6),%d1
	beq.l		t_operr
	cmpi.b		%d1,&ZERO
	beq.l		t_operr
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		t_operr
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	bra.l		dst_snan

	global		srem_sinf
srem_sinf:
	mov.b		DTAG(%a6),%d1
	beq.w		srem_fpn
	cmpi.b		%d1,&ZERO
	beq.w		srem_zro
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		srem_fpn
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	bra.l		dst_snan

#########################################################################
	global		sscale_snorm
	global		sscale_sdnrm
sscale_snorm:
sscale_sdnrm:
	mov.b		DTAG(%a6),%d1
	beq.l		sscale
	cmpi.b		%d1,&ZERO
	beq.l		dst_zero
	cmpi.b		%d1,&INF
	beq.l		dst_inf
	cmpi.b		%d1,&DENORM
	beq.l		sscale
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	bra.l		dst_snan

	global		sscale_szero
sscale_szero:
	mov.b		DTAG(%a6),%d1
	beq.l		sscale
	cmpi.b		%d1,&ZERO
	beq.l		dst_zero
	cmpi.b		%d1,&INF
	beq.l		dst_inf
	cmpi.b		%d1,&DENORM
	beq.l		sscale
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	bra.l		dst_snan

	global		sscale_sinf
sscale_sinf:
	mov.b		DTAG(%a6),%d1
	beq.l		t_operr
	cmpi.b		%d1,&QNAN
	beq.l		dst_qnan
	cmpi.b		%d1,&SNAN
	beq.l		dst_snan
	bra.l		t_operr

########################################################################

#
# sop_sqnan(): The src op for frem/fmod/fscale was a QNAN.
#
	global		sop_sqnan
sop_sqnan:
	mov.b		DTAG(%a6),%d1
	cmpi.b		%d1,&QNAN
	beq.b		dst_qnan
	cmpi.b		%d1,&SNAN
	beq.b		dst_snan
	bra.b		src_qnan

#
# sop_ssnan(): The src op for frem/fmod/fscale was an SNAN.
#
	global		sop_ssnan
sop_ssnan:
	mov.b		DTAG(%a6),%d1
	cmpi.b		%d1,&QNAN
	beq.b		dst_qnan_src_snan
	cmpi.b		%d1,&SNAN
	beq.b		dst_snan
	bra.b		src_snan

dst_qnan_src_snan:
	ori.l		&snaniop_mask,USER_FPSR(%a6) # set NAN/SNAN/AIOP
	bra.b		dst_qnan

#
# dst_qnan(): Return the dst SNAN w/ the SNAN bit set.
#
	global		dst_snan
dst_snan:
	fmov.x		DST(%a1),%fp0		# the fmove sets the SNAN bit
	fmov.l		%fpsr,%d0		# catch resulting status
	or.l		%d0,USER_FPSR(%a6)	# store status
	rts

#
# dst_qnan(): Return the dst QNAN.
#
	global		dst_qnan
dst_qnan:
	fmov.x		DST(%a1),%fp0		# return the non-signalling nan
	tst.b		DST_EX(%a1)		# set ccodes according to QNAN sign
	bmi.b		dst_qnan_m
dst_qnan_p:
	mov.b		&nan_bmask,FPSR_CC(%a6)
	rts
dst_qnan_m:
	mov.b		&neg_bmask+nan_bmask,FPSR_CC(%a6)
	rts

#
# src_snan(): Return the src SNAN w/ the SNAN bit set.
#
	global		src_snan
src_snan:
	fmov.x		SRC(%a0),%fp0		# the fmove sets the SNAN bit
	fmov.l		%fpsr,%d0		# catch resulting status
	or.l		%d0,USER_FPSR(%a6)	# store status
	rts

#
# src_qnan(): Return the src QNAN.
#
	global		src_qnan
src_qnan:
	fmov.x		SRC(%a0),%fp0		# return the non-signalling nan
	tst.b		SRC_EX(%a0)		# set ccodes according to QNAN sign
	bmi.b		dst_qnan_m
src_qnan_p:
	mov.b		&nan_bmask,FPSR_CC(%a6)
	rts
src_qnan_m:
	mov.b		&neg_bmask+nan_bmask,FPSR_CC(%a6)
	rts

#
# fkern2.s:
#	These entry points are used by the exception handler
# routines where an instruction is selected by an index into
# a large jump table corresponding to a given instruction which 
# has been decoded. Flow continues here where we now decode 
# further accoding to the source operand type.
#

	global		fsinh
fsinh:
	mov.b		STAG(%a6),%d1
	beq.l		ssinh
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		src_inf
	cmpi.b		%d1,&DENORM
	beq.l		ssinhd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		flognp1
flognp1:
	mov.b		STAG(%a6),%d1
	beq.l		slognp1
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		sopr_inf
	cmpi.b		%d1,&DENORM
	beq.l		slognp1d
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fetoxm1
fetoxm1:
	mov.b		STAG(%a6),%d1
	beq.l		setoxm1
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		setoxm1i
	cmpi.b		%d1,&DENORM
	beq.l		setoxm1d
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		ftanh
ftanh:
	mov.b		STAG(%a6),%d1
	beq.l		stanh
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		src_one
	cmpi.b		%d1,&DENORM
	beq.l		stanhd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fatan
fatan:
	mov.b		STAG(%a6),%d1
	beq.l		satan
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		spi_2
	cmpi.b		%d1,&DENORM
	beq.l		satand
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fasin
fasin:
	mov.b		STAG(%a6),%d1
	beq.l		sasin
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		sasind
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fatanh
fatanh:
	mov.b		STAG(%a6),%d1
	beq.l		satanh
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		satanhd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fsine
fsine:
	mov.b		STAG(%a6),%d1
	beq.l		ssin
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		ssind
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		ftan
ftan:
	mov.b		STAG(%a6),%d1
	beq.l		stan
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		stand
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fetox
fetox:
	mov.b		STAG(%a6),%d1
	beq.l		setox
	cmpi.b		%d1,&ZERO
	beq.l		ld_pone
	cmpi.b		%d1,&INF
	beq.l		szr_inf
	cmpi.b		%d1,&DENORM
	beq.l		setoxd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		ftwotox
ftwotox:
	mov.b		STAG(%a6),%d1
	beq.l		stwotox
	cmpi.b		%d1,&ZERO
	beq.l		ld_pone
	cmpi.b		%d1,&INF
	beq.l		szr_inf
	cmpi.b		%d1,&DENORM
	beq.l		stwotoxd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		ftentox
ftentox:
	mov.b		STAG(%a6),%d1
	beq.l		stentox
	cmpi.b		%d1,&ZERO
	beq.l		ld_pone
	cmpi.b		%d1,&INF
	beq.l		szr_inf
	cmpi.b		%d1,&DENORM
	beq.l		stentoxd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		flogn
flogn:
	mov.b		STAG(%a6),%d1
	beq.l		slogn
	cmpi.b		%d1,&ZERO
	beq.l		t_dz2
	cmpi.b		%d1,&INF
	beq.l		sopr_inf
	cmpi.b		%d1,&DENORM
	beq.l		slognd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		flog10
flog10:
	mov.b		STAG(%a6),%d1
	beq.l		slog10
	cmpi.b		%d1,&ZERO
	beq.l		t_dz2
	cmpi.b		%d1,&INF
	beq.l		sopr_inf
	cmpi.b		%d1,&DENORM
	beq.l		slog10d
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		flog2
flog2:
	mov.b		STAG(%a6),%d1
	beq.l		slog2
	cmpi.b		%d1,&ZERO
	beq.l		t_dz2
	cmpi.b		%d1,&INF
	beq.l		sopr_inf
	cmpi.b		%d1,&DENORM
	beq.l		slog2d
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fcosh
fcosh:
	mov.b		STAG(%a6),%d1
	beq.l		scosh
	cmpi.b		%d1,&ZERO
	beq.l		ld_pone
	cmpi.b		%d1,&INF
	beq.l		ld_pinf
	cmpi.b		%d1,&DENORM
	beq.l		scoshd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		facos
facos:
	mov.b		STAG(%a6),%d1
	beq.l		sacos
	cmpi.b		%d1,&ZERO
	beq.l		ld_ppi2
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		sacosd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fcos
fcos:
	mov.b		STAG(%a6),%d1
	beq.l		scos
	cmpi.b		%d1,&ZERO
	beq.l		ld_pone
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		scosd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fgetexp
fgetexp:
	mov.b		STAG(%a6),%d1
	beq.l		sgetexp
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		sgetexpd
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fgetman
fgetman:
	mov.b		STAG(%a6),%d1
	beq.l		sgetman
	cmpi.b		%d1,&ZERO
	beq.l		src_zero
	cmpi.b		%d1,&INF
	beq.l		t_operr
	cmpi.b		%d1,&DENORM
	beq.l		sgetmand
	cmpi.b		%d1,&QNAN
	beq.l		src_qnan
	bra.l		src_snan

	global		fsincos
fsincos:
	mov.b		STAG(%a6),%d1
	beq.l		ssincos
	cmpi.b		%d1,&ZERO
	beq.l		ssincosz
	cmpi.b		%d1,&INF
	beq.l		ssincosi
	cmpi.b		%d1,&DENORM
	beq.l		ssincosd
	cmpi.b		%d1,&QNAN
	beq.l		ssincosqnan
	bra.l		ssincossnan

	global		fmod
fmod:
	mov.b		STAG(%a6),%d1
	beq.l		smod_snorm
	cmpi.b		%d1,&ZERO
	beq.l		smod_szero
	cmpi.b		%d1,&INF
	beq.l		smod_sinf
	cmpi.b		%d1,&DENORM
	beq.l		smod_sdnrm
	cmpi.b		%d1,&QNAN
	beq.l		sop_sqnan
	bra.l		sop_ssnan

	global		frem
frem:
	mov.b		STAG(%a6),%d1
	beq.l		srem_snorm
	cmpi.b		%d1,&ZERO
	beq.l		srem_szero
	cmpi.b		%d1,&INF
	beq.l		srem_sinf
	cmpi.b		%d1,&DENORM
	beq.l		srem_sdnrm
	cmpi.b		%d1,&QNAN
	beq.l		sop_sqnan
	bra.l		sop_ssnan

	global		fscale
fscale:
	mov.b		STAG(%a6),%d1
	beq.l		sscale_snorm
	cmpi.b		%d1,&ZERO
	beq.l		sscale_szero
	cmpi.b		%d1,&INF
	beq.l		sscale_sinf
	cmpi.b		%d1,&DENORM
	beq.l		sscale_sdnrm
	cmpi.b		%d1,&QNAN
	beq.l		sop_sqnan
	bra.l		sop_ssnan

#########################################################################
# XDEF ****************************************************************	#
# 	fgen_except(): catch an exception during transcendental 	#
#		       emulation					#
#									#
# XREF ****************************************************************	#
#	fmul() - emulate a multiply instruction				# 
#	fadd() - emulate an add instruction				#
#	fin() - emulate an fmove instruction				#
#									#
# INPUT ***************************************************************	#
#	fp0 = destination operand					#
#	d0  = type of instruction that took exception			#
#	fsave frame = source operand					#
# 									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP							#
#									#
# ALGORITHM ***********************************************************	#
# 	An exception occurred on the last instruction of the 		#
# transcendental emulation. hopefully, this won't be happening much 	#
# because it will be VERY slow.						#
# 	The only exceptions capable of passing through here are		#
# Overflow, Underflow, and Unsupported Data Type.			#
#									#
#########################################################################

	global		fgen_except
fgen_except:
	cmpi.b		0x3(%sp),&0x7		# is exception UNSUPP?
	beq.b		fge_unsupp		# yes

	mov.b		&NORM,STAG(%a6)

fge_cont:
	mov.b		&NORM,DTAG(%a6)

# ok, I have a problem with putting the dst op at FP_DST. the emulation
# routines aren't supposed to alter the operands but we've just squashed
# FP_DST here...

# 8/17/93 - this turns out to be more of a "cleanliness" standpoint
# then a potential bug. to begin with, only the dyadic functions
# frem,fmod, and fscale would get the dst trashed here. But, for
# the 060SP, the FP_DST is never used again anyways.
	fmovm.x		&0x80,FP_DST(%a6)	# dst op is in fp0

	lea		0x4(%sp),%a0		# pass: ptr to src op
	lea		FP_DST(%a6),%a1		# pass: ptr to dst op

	cmpi.b		%d1,&FMOV_OP
	beq.b		fge_fin			# it was an "fmov"
	cmpi.b		%d1,&FADD_OP
	beq.b		fge_fadd		# it was an "fadd"
fge_fmul:
	bsr.l		fmul
	rts
fge_fadd:
	bsr.l		fadd
	rts
fge_fin:
	bsr.l		fin
	rts

fge_unsupp:
	mov.b		&DENORM,STAG(%a6)
	bra.b		fge_cont

#
# This table holds the offsets of the emulation routines for each individual
# math operation relative to the address of this table. Included are
# routines like fadd/fmul/fabs as well as the transcendentals.
# The location within the table is determined by the extension bits of the
# operation longword.
#

	swbeg		&109
tbl_unsupp:
	long		fin	 	- tbl_unsupp	# 00: fmove
	long		fint	 	- tbl_unsupp	# 01: fint
	long		fsinh	 	- tbl_unsupp	# 02: fsinh
	long		fintrz	 	- tbl_unsupp	# 03: fintrz
	long		fsqrt	 	- tbl_unsupp	# 04: fsqrt
	long		tbl_unsupp	- tbl_unsupp
	long		flognp1		- tbl_unsupp	# 06: flognp1
	long		tbl_unsupp	- tbl_unsupp
	long		fetoxm1		- tbl_unsupp	# 08: fetoxm1
	long		ftanh		- tbl_unsupp	# 09: ftanh
	long		fatan		- tbl_unsupp	# 0a: fatan
	long		tbl_unsupp	- tbl_unsupp
	long		fasin		- tbl_unsupp	# 0c: fasin
	long		fatanh		- tbl_unsupp	# 0d: fatanh
	long		fsine		- tbl_unsupp	# 0e: fsin
	long		ftan		- tbl_unsupp	# 0f: ftan
	long		fetox		- tbl_unsupp	# 10: fetox
	long		ftwotox		- tbl_unsupp	# 11: ftwotox
	long		ftentox		- tbl_unsupp	# 12: ftentox
	long		tbl_unsupp	- tbl_unsupp
	long		flogn		- tbl_unsupp	# 14: flogn
	long		flog10		- tbl_unsupp	# 15: flog10
	long		flog2		- tbl_unsupp	# 16: flog2
	long		tbl_unsupp	- tbl_unsupp
	long		fabs		- tbl_unsupp 	# 18: fabs
	long		fcosh		- tbl_unsupp	# 19: fcosh
	long		fneg		- tbl_unsupp 	# 1a: fneg
	long		tbl_unsupp	- tbl_unsupp
	long		facos		- tbl_unsupp	# 1c: facos
	long		fcos		- tbl_unsupp	# 1d: fcos
	long		fgetexp		- tbl_unsupp	# 1e: fgetexp
	long		fgetman		- tbl_unsupp	# 1f: fgetman
	long		fdiv		- tbl_unsupp 	# 20: fdiv
	long		fmod		- tbl_unsupp	# 21: fmod
	long		fadd		- tbl_unsupp 	# 22: fadd
	long		fmul		- tbl_unsupp 	# 23: fmul
	long		fsgldiv		- tbl_unsupp 	# 24: fsgldiv
	long		frem		- tbl_unsupp	# 25: frem
	long		fscale		- tbl_unsupp	# 26: fscale
	long		fsglmul		- tbl_unsupp 	# 27: fsglmul
	long		fsub		- tbl_unsupp 	# 28: fsub
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		fsincos		- tbl_unsupp	# 30: fsincos
	long		fsincos		- tbl_unsupp	# 31: fsincos
	long		fsincos		- tbl_unsupp	# 32: fsincos
	long		fsincos		- tbl_unsupp	# 33: fsincos
	long		fsincos		- tbl_unsupp	# 34: fsincos
	long		fsincos		- tbl_unsupp	# 35: fsincos
	long		fsincos		- tbl_unsupp	# 36: fsincos
	long		fsincos		- tbl_unsupp	# 37: fsincos
	long		fcmp		- tbl_unsupp 	# 38: fcmp
	long		tbl_unsupp	- tbl_unsupp
	long		ftst		- tbl_unsupp 	# 3a: ftst
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		fsin		- tbl_unsupp 	# 40: fsmove
	long		fssqrt		- tbl_unsupp 	# 41: fssqrt
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		fdin		- tbl_unsupp	# 44: fdmove
	long		fdsqrt		- tbl_unsupp 	# 45: fdsqrt
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		fsabs		- tbl_unsupp 	# 58: fsabs
	long		tbl_unsupp	- tbl_unsupp
	long		fsneg		- tbl_unsupp 	# 5a: fsneg
	long		tbl_unsupp	- tbl_unsupp
	long		fdabs		- tbl_unsupp	# 5c: fdabs
	long		tbl_unsupp	- tbl_unsupp
	long		fdneg		- tbl_unsupp 	# 5e: fdneg
	long		tbl_unsupp	- tbl_unsupp
	long		fsdiv		- tbl_unsupp	# 60: fsdiv
	long		tbl_unsupp	- tbl_unsupp
	long		fsadd		- tbl_unsupp	# 62: fsadd
	long		fsmul		- tbl_unsupp	# 63: fsmul
	long		fddiv		- tbl_unsupp 	# 64: fddiv
	long		tbl_unsupp	- tbl_unsupp
	long		fdadd		- tbl_unsupp	# 66: fdadd
	long		fdmul		- tbl_unsupp 	# 67: fdmul
	long		fssub		- tbl_unsupp	# 68: fssub
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		tbl_unsupp	- tbl_unsupp
	long		fdsub		- tbl_unsupp 	# 6c: fdsub

#########################################################################
# XDEF ****************************************************************	#
# 	fmul(): emulates the fmul instruction				#
#	fsmul(): emulates the fsmul instruction				#
#	fdmul(): emulates the fdmul instruction				#
#									#
# XREF ****************************************************************	#
#	scale_to_zero_src() - scale src exponent to zero		#
#	scale_to_zero_dst() - scale dst exponent to zero		#
#	unf_res() - return default underflow result			#
#	ovf_res() - return default overflow result			#
# 	res_qnan() - return QNAN result					#
# 	res_snan() - return SNAN result					#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	a1 = pointer to extended precision destination operand		#
#	d0  rnd prec,mode						#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
#	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms/denorms into ext/sgl/dbl precision.				#
#	For norms/denorms, scale the exponents such that a multiply	#
# instruction won't cause an exception. Use the regular fmul to		#
# compute a result. Check if the regular operands would have taken	#
# an exception. If so, return the default overflow/underflow result	#
# and return the EXOP if exceptions are enabled. Else, scale the 	#
# result operand to the proper exponent.				#
#									#
#########################################################################

	align 		0x10
tbl_fmul_ovfl:
	long		0x3fff - 0x7ffe		# ext_max
	long		0x3fff - 0x407e		# sgl_max
	long		0x3fff - 0x43fe		# dbl_max
tbl_fmul_unfl:
	long		0x3fff + 0x0001		# ext_unfl
	long		0x3fff - 0x3f80		# sgl_unfl
	long		0x3fff - 0x3c00		# dbl_unfl

	global		fsmul
fsmul:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl prec
	bra.b		fmul

	global		fdmul
fdmul:
	andi.b		&0x30,%d0
	ori.b		&d_mode*0x10,%d0	# insert dbl prec

	global		fmul
fmul:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info

	clr.w		%d1
	mov.b		DTAG(%a6),%d1
	lsl.b		&0x3,%d1
	or.b		STAG(%a6),%d1		# combine src tags
	bne.w		fmul_not_norm		# optimize on non-norm input

fmul_norm:
	mov.w		DST_EX(%a1),FP_SCR1_EX(%a6)
	mov.l		DST_HI(%a1),FP_SCR1_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	bsr.l		scale_to_zero_src	# scale src exponent
	mov.l		%d0,-(%sp)		# save scale factor 1

	bsr.l		scale_to_zero_dst	# scale dst exponent

	add.l		%d0,(%sp)		# SCALE_FACTOR = scale1 + scale2

	mov.w		2+L_SCR3(%a6),%d1	# fetch precision
	lsr.b		&0x6,%d1		# shift to lo bits
	mov.l		(%sp)+,%d0		# load S.F.
	cmp.l		%d0,(tbl_fmul_ovfl.w,%pc,%d1.w*4) # would result ovfl?
	beq.w		fmul_may_ovfl		# result may rnd to overflow
	blt.w		fmul_ovfl		# result will overflow

	cmp.l		%d0,(tbl_fmul_unfl.w,%pc,%d1.w*4) # would result unfl?
	beq.w		fmul_may_unfl		# result may rnd to no unfl
	bgt.w		fmul_unfl		# result will underflow

#
# NORMAL:
# - the result of the multiply operation will neither overflow nor underflow.
# - do the multiply to the proper precision and rounding mode. 
# - scale the result exponent using the scale factor. if both operands were
# normalized then we really don't need to go through this scaling. but for now,
# this will do.
#
fmul_normal:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst operand

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmul.x		FP_SCR0(%a6),%fp0	# execute multiply	

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fmul_normal_exit:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# load {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts

#
# OVERFLOW:
# - the result of the multiply operation is an overflow.
# - do the multiply to the proper precision and rounding mode in order to
# set the inexact bits.
# - calculate the default result and return it in fp0.
# - if overflow or inexact is enabled, we need a multiply result rounded to
# extended precision. if the original operation was extended, then we have this
# result. if the original operation was single or double, we have to do another
# multiply using extended precision and the correct rounding mode. the result
# of this operation then has its exponent scaled by -0x6000 to create the
# exceptional operand.
#
fmul_ovfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst operand

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmul.x		FP_SCR0(%a6),%fp0	# execute multiply	

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

# save setting this until now because this is where fmul_may_ovfl may jump in
fmul_ovfl_tst:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fmul_ovfl_ena		# yes

# calculate the default result
fmul_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass rnd prec,mode
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

#
# OVFL is enabled; Create EXOP:
# - if precision is extended, then we have the EXOP. simply bias the exponent
# with an extra -0x6000. if the precision is single or double, we need to
# calculate a result rounded to extended precision.
#
fmul_ovfl_ena:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# test the rnd prec
	bne.b		fmul_ovfl_ena_sd	# it's sgl or dbl

fmul_ovfl_ena_cont:
	fmovm.x		&0x80,FP_SCR0(%a6)	# move result to stack

	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.w		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	subi.l		&0x6000,%d1		# subtract bias
	andi.w		&0x7fff,%d1		# clear sign bit
	andi.w		&0x8000,%d2		# keep old sign
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.b		fmul_ovfl_dis

fmul_ovfl_ena_sd:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst operand

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# keep rnd mode only
	fmov.l		%d1,%fpcr		# set FPCR

	fmul.x		FP_SCR0(%a6),%fp0	# execute multiply

	fmov.l		&0x0,%fpcr		# clear FPCR
	bra.b		fmul_ovfl_ena_cont

#
# may OVERFLOW:
# - the result of the multiply operation MAY overflow.
# - do the multiply to the proper precision and rounding mode in order to
# set the inexact bits.
# - calculate the default result and return it in fp0.
#
fmul_may_ovfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmul.x		FP_SCR0(%a6),%fp0	# execute multiply
	
	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x2		# is |result| >= 2.b?
	fbge.w		fmul_ovfl_tst		# yes; overflow has occurred
	
# no, it didn't overflow; we have correct result
	bra.w		fmul_normal_exit

#
# UNDERFLOW:
# - the result of the multiply operation is an underflow.
# - do the multiply to the proper precision and rounding mode in order to
# set the inexact bits.
# - calculate the default result and return it in fp0.
# - if overflow or inexact is enabled, we need a multiply result rounded to
# extended precision. if the original operation was extended, then we have this
# result. if the original operation was single or double, we have to do another
# multiply using extended precision and the correct rounding mode. the result
# of this operation then has its exponent scaled by -0x6000 to create the
# exceptional operand.
#
fmul_unfl:	
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

# for fun, let's use only extended precision, round to zero. then, let
# the unf_res() routine figure out all the rest.
# will we get the correct answer.
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst operand

	fmov.l		&rz_mode*0x10,%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmul.x		FP_SCR0(%a6),%fp0	# execute multiply

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fmul_unfl_ena		# yes

fmul_unfl_dis:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result

	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# unf_res2 may have set 'Z'
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts

#
# UNFL is enabled. 
#
fmul_unfl_ena:
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# is precision extended?
	bne.b		fmul_unfl_ena_sd	# no, sgl or dbl

# if the rnd mode is anything but RZ, then we have to re-do the above
# multiplication becuase we used RZ for all.
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

fmul_unfl_ena_cont:
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmul.x		FP_SCR0(%a6),%fp1	# execute multiply	

	fmov.l		&0x0,%fpcr		# clear FPCR

	fmovm.x		&0x40,FP_SCR0(%a6)	# save result to stack
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	addi.l		&0x6000,%d1		# add bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.w		fmul_unfl_dis

fmul_unfl_ena_sd:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# use only rnd mode
	fmov.l		%d1,%fpcr		# set FPCR

	bra.b		fmul_unfl_ena_cont

# MAY UNDERFLOW:
# -use the correct rounding mode and precision. this code favors operations
# that do not underflow.
fmul_may_unfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst operand

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmul.x		FP_SCR0(%a6),%fp0	# execute multiply	

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x2		# is |result| > 2.b?
	fbgt.w		fmul_normal_exit	# no; no underflow occurred
	fblt.w		fmul_unfl		# yes; underflow occurred

#
# we still don't know if underflow occurred. result is ~ equal to 2. but,
# we don't know if the result was an underflow that rounded up to a 2 or
# a normalized number that rounded down to a 2. so, redo the entire operation
# using RZ as the rounding mode to see what the pre-rounded result is.
# this case should be relatively rare.
#
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst operand

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# keep rnd prec
	ori.b		&rz_mode*0x10,%d1	# insert RZ
	
	fmov.l		%d1,%fpcr		# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmul.x		FP_SCR0(%a6),%fp1	# execute multiply	

	fmov.l		&0x0,%fpcr		# clear FPCR
	fabs.x		%fp1			# make absolute value
	fcmp.b		%fp1,&0x2		# is |result| < 2.b?
	fbge.w		fmul_normal_exit	# no; no underflow occurred
	bra.w		fmul_unfl		# yes, underflow occurred

################################################################################

#
# Multiply: inputs are not both normalized; what are they?
#
fmul_not_norm:
	mov.w		(tbl_fmul_op.b,%pc,%d1.w*2),%d1
	jmp		(tbl_fmul_op.b,%pc,%d1.w)

	swbeg		&48
tbl_fmul_op:
	short		fmul_norm	- tbl_fmul_op # NORM x NORM
	short		fmul_zero	- tbl_fmul_op # NORM x ZERO
	short		fmul_inf_src	- tbl_fmul_op # NORM x INF
	short		fmul_res_qnan	- tbl_fmul_op # NORM x QNAN
	short		fmul_norm	- tbl_fmul_op # NORM x DENORM
	short		fmul_res_snan	- tbl_fmul_op # NORM x SNAN
	short		tbl_fmul_op	- tbl_fmul_op #
	short		tbl_fmul_op	- tbl_fmul_op #

	short		fmul_zero	- tbl_fmul_op # ZERO x NORM
	short		fmul_zero	- tbl_fmul_op # ZERO x ZERO
	short		fmul_res_operr	- tbl_fmul_op # ZERO x INF
	short		fmul_res_qnan	- tbl_fmul_op # ZERO x QNAN
	short		fmul_zero	- tbl_fmul_op # ZERO x DENORM
	short		fmul_res_snan	- tbl_fmul_op # ZERO x SNAN
	short		tbl_fmul_op	- tbl_fmul_op #
	short		tbl_fmul_op	- tbl_fmul_op #

	short		fmul_inf_dst	- tbl_fmul_op # INF x NORM
	short		fmul_res_operr	- tbl_fmul_op # INF x ZERO
	short		fmul_inf_dst	- tbl_fmul_op # INF x INF
	short		fmul_res_qnan	- tbl_fmul_op # INF x QNAN
	short		fmul_inf_dst	- tbl_fmul_op # INF x DENORM
	short		fmul_res_snan	- tbl_fmul_op # INF x SNAN
	short		tbl_fmul_op	- tbl_fmul_op #
	short		tbl_fmul_op	- tbl_fmul_op #

	short		fmul_res_qnan	- tbl_fmul_op # QNAN x NORM
	short		fmul_res_qnan	- tbl_fmul_op # QNAN x ZERO
	short		fmul_res_qnan	- tbl_fmul_op # QNAN x INF
	short		fmul_res_qnan	- tbl_fmul_op # QNAN x QNAN
	short		fmul_res_qnan	- tbl_fmul_op # QNAN x DENORM
	short		fmul_res_snan	- tbl_fmul_op # QNAN x SNAN
	short		tbl_fmul_op	- tbl_fmul_op #
	short		tbl_fmul_op	- tbl_fmul_op #

	short		fmul_norm	- tbl_fmul_op # NORM x NORM
	short		fmul_zero	- tbl_fmul_op # NORM x ZERO
	short		fmul_inf_src	- tbl_fmul_op # NORM x INF
	short		fmul_res_qnan	- tbl_fmul_op # NORM x QNAN
	short		fmul_norm	- tbl_fmul_op # NORM x DENORM
	short		fmul_res_snan	- tbl_fmul_op # NORM x SNAN
	short		tbl_fmul_op	- tbl_fmul_op #
	short		tbl_fmul_op	- tbl_fmul_op #

	short		fmul_res_snan	- tbl_fmul_op # SNAN x NORM
	short		fmul_res_snan	- tbl_fmul_op # SNAN x ZERO
	short		fmul_res_snan	- tbl_fmul_op # SNAN x INF
	short		fmul_res_snan	- tbl_fmul_op # SNAN x QNAN
	short		fmul_res_snan	- tbl_fmul_op # SNAN x DENORM
	short		fmul_res_snan	- tbl_fmul_op # SNAN x SNAN
	short		tbl_fmul_op	- tbl_fmul_op #
	short		tbl_fmul_op	- tbl_fmul_op #

fmul_res_operr:
	bra.l		res_operr
fmul_res_snan:
	bra.l		res_snan
fmul_res_qnan:
	bra.l		res_qnan

#
# Multiply: (Zero x Zero) || (Zero x norm) || (Zero x denorm)
#
	global		fmul_zero		# global for fsglmul
fmul_zero:
	mov.b		SRC_EX(%a0),%d0		# exclusive or the signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d0,%d1
	bpl.b		fmul_zero_p		# result ZERO is pos.
fmul_zero_n:
	fmov.s		&0x80000000,%fp0	# load -ZERO
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6) # set Z/N
	rts
fmul_zero_p:
	fmov.s		&0x00000000,%fp0	# load +ZERO
	mov.b		&z_bmask,FPSR_CC(%a6)	# set Z
	rts

#
# Multiply: (inf x inf) || (inf x norm) || (inf x denorm)
#
# Note: The j-bit for an infinity is a don't-care. However, to be
# strictly compatible w/ the 68881/882, we make sure to return an
# INF w/ the j-bit set if the input INF j-bit was set. Destination
# INFs take priority.
#
	global		fmul_inf_dst		# global for fsglmul
fmul_inf_dst:
	fmovm.x		DST(%a1),&0x80		# return INF result in fp0
	mov.b		SRC_EX(%a0),%d0		# exclusive or the signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d0,%d1
	bpl.b		fmul_inf_dst_p		# result INF is pos.
fmul_inf_dst_n:
	fabs.x		%fp0			# clear result sign
	fneg.x		%fp0			# set result sign
	mov.b		&inf_bmask+neg_bmask,FPSR_CC(%a6) # set INF/N
	rts
fmul_inf_dst_p:
	fabs.x		%fp0			# clear result sign
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set INF
	rts

	global		fmul_inf_src		# global for fsglmul
fmul_inf_src:
	fmovm.x		SRC(%a0),&0x80		# return INF result in fp0
	mov.b		SRC_EX(%a0),%d0		# exclusive or the signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d0,%d1
	bpl.b		fmul_inf_dst_p		# result INF is pos.
	bra.b		fmul_inf_dst_n

#########################################################################
# XDEF ****************************************************************	#
#	fin(): emulates the fmove instruction				#
#	fsin(): emulates the fsmove instruction				#
#	fdin(): emulates the fdmove instruction				#
#									#
# XREF ****************************************************************	#
#	norm() - normalize mantissa for EXOP on denorm			#
#	scale_to_zero_src() - scale src exponent to zero		#
#	ovf_res() - return default overflow result			#
# 	unf_res() - return default underflow result			#
#	res_qnan_1op() - return QNAN result				#
#	res_snan_1op() - return SNAN result				#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	d0 = round prec/mode						#
# 									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
# 	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms into extended, single, and double precision.			#
# 	Norms can be emulated w/ a regular fmove instruction. For	#
# sgl/dbl, must scale exponent and perform an "fmove". Check to see	#
# if the result would have overflowed/underflowed. If so, use unf_res()	#
# or ovf_res() to return the default result. Also return EXOP if	#
# exception is enabled. If no exception, return the default result.	#
#	Unnorms don't pass through here.				#
#									#
#########################################################################

	global		fsin
fsin:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl precision
	bra.b		fin

	global		fdin
fdin:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl precision

	global		fin
fin:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info

	mov.b		STAG(%a6),%d1		# fetch src optype tag
	bne.w		fin_not_norm		# optimize on non-norm input
		
#
# FP MOVE IN: NORMs and DENORMs ONLY!
#
fin_norm:
	andi.b		&0xc0,%d0		# is precision extended?
	bne.w		fin_not_ext		# no, so go handle dbl or sgl

#
# precision selected is extended. so...we cannot get an underflow
# or overflow because of rounding to the correct precision. so...
# skip the scaling and unscaling...
#
	tst.b		SRC_EX(%a0)		# is the operand negative?
	bpl.b		fin_norm_done		# no
	bset		&neg_bit,FPSR_CC(%a6)	# yes, so set 'N' ccode bit
fin_norm_done:
	fmovm.x		SRC(%a0),&0x80		# return result in fp0
	rts

#
# for an extended precision DENORM, the UNFL exception bit is set
# the accrued bit is NOT set in this instance(no inexactness!)
#
fin_denorm:
	andi.b		&0xc0,%d0		# is precision extended?
	bne.w		fin_not_ext		# no, so go handle dbl or sgl

	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit
	tst.b		SRC_EX(%a0)		# is the operand negative?
	bpl.b		fin_denorm_done		# no
	bset		&neg_bit,FPSR_CC(%a6)	# yes, so set 'N' ccode bit
fin_denorm_done:
	fmovm.x		SRC(%a0),&0x80		# return result in fp0
	btst		&unfl_bit,FPCR_ENABLE(%a6) # is UNFL enabled?
	bne.b		fin_denorm_unfl_ena	# yes
	rts

#
# the input is an extended DENORM and underflow is enabled in the FPCR.
# normalize the mantissa and add the bias of 0x6000 to the resulting negative
# exponent and insert back into the operand.
#
fin_denorm_unfl_ena:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	lea		FP_SCR0(%a6),%a0	# pass: ptr to operand
	bsr.l		norm			# normalize result
	neg.w		%d0			# new exponent = -(shft val)
	addi.w		&0x6000,%d0		# add new bias to exponent
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch old sign,exp
	andi.w		&0x8000,%d1		# keep old sign
	andi.w		&0x7fff,%d0		# clear sign position
	or.w		%d1,%d0			# concat new exo,old sign
	mov.w		%d0,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	rts

#
# operand is to be rounded to single or double precision
#	
fin_not_ext:
	cmpi.b		%d0,&s_mode*0x10 	# separate sgl/dbl prec
	bne.b		fin_dbl

#
# operand is to be rounded to single precision
#
fin_sgl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3f80	# will move in underflow?
	bge.w		fin_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x407e	# will move in overflow?
	beq.w		fin_sd_may_ovfl		# maybe; go check
	blt.w		fin_sd_ovfl		# yes; go handle overflow

#
# operand will NOT overflow or underflow when moved into the fp reg file
#
fin_sd_normal:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fmov.x		FP_SCR0(%a6),%fp0	# perform move

	fmov.l		%fpsr,%d1		# save FPSR
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fin_sd_normal_exit:
	mov.l		%d2,-(%sp)		# save d2
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result
	mov.w		FP_SCR0_EX(%a6),%d1	# load {sgn,exp}
	mov.w		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	andi.w		&0x8000,%d2		# keep old sign
	or.w		%d1,%d2			# concat old sign,new exponent
	mov.w		%d2,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

#
# operand is to be rounded to double precision
#
fin_dbl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3c00	# will move in underflow?
	bge.w		fin_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x43fe	# will move in overflow?
	beq.w		fin_sd_may_ovfl		# maybe; go check
	blt.w		fin_sd_ovfl		# yes; go handle overflow
	bra.w		fin_sd_normal		# no; ho handle normalized op

#
# operand WILL underflow when moved in to the fp register file
#
fin_sd_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	tst.b		FP_SCR0_EX(%a6)		# is operand negative?
	bpl.b		fin_sd_unfl_tst
	bset		&neg_bit,FPSR_CC(%a6)	# set 'N' ccode bit

# if underflow or inexact is enabled, then go calculate the EXOP first.
fin_sd_unfl_tst:
	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fin_sd_unfl_ena		# yes

fin_sd_unfl_dis:
	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# unf_res may have set 'Z'
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts	

#
# operand will underflow AND underflow or inexact is enabled. 
# therefore, we must return the result rounded to extended precision.
#
fin_sd_unfl_ena:
	mov.l		FP_SCR0_HI(%a6),FP_SCR1_HI(%a6)
	mov.l		FP_SCR0_LO(%a6),FP_SCR1_LO(%a6)
	mov.w		FP_SCR0_EX(%a6),%d1	# load current exponent

	mov.l		%d2,-(%sp)		# save d2
	mov.w		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# subtract scale factor
	andi.w		&0x8000,%d2		# extract old sign
	addi.l		&0x6000,%d1		# add new bias
	andi.w		&0x7fff,%d1
	or.w		%d1,%d2			# concat old sign,new exp
	mov.w		%d2,FP_SCR1_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR1(%a6),&0x40	# return EXOP in fp1
	mov.l		(%sp)+,%d2		# restore d2
	bra.b		fin_sd_unfl_dis

#
# operand WILL overflow.
#
fin_sd_ovfl:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fmov.x		FP_SCR0(%a6),%fp0	# perform move

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# save FPSR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fin_sd_ovfl_tst:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fin_sd_ovfl_ena		# yes

#
# OVFL is not enabled; therefore, we must create the default result by
# calling ovf_res().
#
fin_sd_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass: prec,mode
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

#
# OVFL is enabled.
# the INEX2 bit has already been updated by the round to the correct precision.
# now, round to extended(and don't alter the FPSR).
#
fin_sd_ovfl_ena:
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	sub.l		&0x6000,%d1		# subtract bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.b		fin_sd_ovfl_dis

#
# the move in MAY overflow. so...
#
fin_sd_may_ovfl:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fmov.x		FP_SCR0(%a6),%fp0	# perform the move

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x2		# is |result| >= 2.b?
	fbge.w		fin_sd_ovfl_tst		# yes; overflow has occurred

# no, it didn't overflow; we have correct result
	bra.w		fin_sd_normal_exit

##########################################################################

#
# operand is not a NORM: check its optype and branch accordingly
#
fin_not_norm:
	cmpi.b		%d1,&DENORM		# weed out DENORM
	beq.w		fin_denorm
	cmpi.b		%d1,&SNAN		# weed out SNANs
	beq.l		res_snan_1op
	cmpi.b		%d1,&QNAN		# weed out QNANs
	beq.l		res_qnan_1op

#
# do the fmove in; at this point, only possible ops are ZERO and INF.
# use fmov to determine ccodes.
# prec:mode should be zero at this point but it won't affect answer anyways.
#
	fmov.x		SRC(%a0),%fp0		# do fmove in
	fmov.l		%fpsr,%d0		# no exceptions possible
	rol.l		&0x8,%d0		# put ccodes in lo byte
	mov.b		%d0,FPSR_CC(%a6)	# insert correct ccodes
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	fdiv(): emulates the fdiv instruction				#
#	fsdiv(): emulates the fsdiv instruction				#
#	fddiv(): emulates the fddiv instruction				#
#									#
# XREF ****************************************************************	#
#	scale_to_zero_src() - scale src exponent to zero		#
#	scale_to_zero_dst() - scale dst exponent to zero		#
#	unf_res() - return default underflow result			#
#	ovf_res() - return default overflow result			#
# 	res_qnan() - return QNAN result					#
# 	res_snan() - return SNAN result					#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	a1 = pointer to extended precision destination operand		#
#	d0  rnd prec,mode						#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
#	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms/denorms into ext/sgl/dbl precision.				#
#	For norms/denorms, scale the exponents such that a divide	#
# instruction won't cause an exception. Use the regular fdiv to		#
# compute a result. Check if the regular operands would have taken	#
# an exception. If so, return the default overflow/underflow result	#
# and return the EXOP if exceptions are enabled. Else, scale the 	#
# result operand to the proper exponent.				#
#									#
#########################################################################

	align		0x10
tbl_fdiv_unfl:
	long		0x3fff - 0x0000		# ext_unfl
	long		0x3fff - 0x3f81		# sgl_unfl
	long		0x3fff - 0x3c01		# dbl_unfl

tbl_fdiv_ovfl:
	long		0x3fff - 0x7ffe		# ext overflow exponent
	long		0x3fff - 0x407e		# sgl overflow exponent
	long		0x3fff - 0x43fe		# dbl overflow exponent

	global		fsdiv
fsdiv:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl prec
	bra.b		fdiv

	global		fddiv
fddiv:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl prec

	global		fdiv
fdiv:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info

	clr.w		%d1
	mov.b		DTAG(%a6),%d1
	lsl.b		&0x3,%d1
	or.b		STAG(%a6),%d1		# combine src tags

	bne.w		fdiv_not_norm		# optimize on non-norm input
		
#
# DIVIDE: NORMs and DENORMs ONLY!
#
fdiv_norm:
	mov.w		DST_EX(%a1),FP_SCR1_EX(%a6)
	mov.l		DST_HI(%a1),FP_SCR1_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	bsr.l		scale_to_zero_src	# scale src exponent
	mov.l		%d0,-(%sp)		# save scale factor 1

	bsr.l		scale_to_zero_dst	# scale dst exponent

	neg.l		(%sp)			# SCALE FACTOR = scale1 - scale2
	add.l		%d0,(%sp)

	mov.w		2+L_SCR3(%a6),%d1	# fetch precision
	lsr.b		&0x6,%d1		# shift to lo bits
	mov.l		(%sp)+,%d0		# load S.F.
	cmp.l		%d0,(tbl_fdiv_ovfl.b,%pc,%d1.w*4) # will result overflow?
	ble.w		fdiv_may_ovfl		# result will overflow

	cmp.l		%d0,(tbl_fdiv_unfl.w,%pc,%d1.w*4) # will result underflow?
	beq.w		fdiv_may_unfl		# maybe
	bgt.w		fdiv_unfl		# yes; go handle underflow

fdiv_normal:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# save FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fdiv.x		FP_SCR0(%a6),%fp0	# perform divide

	fmov.l		%fpsr,%d1		# save FPSR
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fdiv_normal_exit:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store result on stack
	mov.l		%d2,-(%sp)		# store d2
	mov.w		FP_SCR0_EX(%a6),%d1	# load {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

tbl_fdiv_ovfl2:
	long		0x7fff
	long		0x407f
	long		0x43ff

fdiv_no_ovfl:
	mov.l		(%sp)+,%d0		# restore scale factor
	bra.b		fdiv_normal_exit
	
fdiv_may_ovfl:
	mov.l		%d0,-(%sp)		# save scale factor

	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# set FPSR

	fdiv.x		FP_SCR0(%a6),%fp0	# execute divide

	fmov.l		%fpsr,%d0
	fmov.l		&0x0,%fpcr

	or.l		%d0,USER_FPSR(%a6)	# save INEX,N

	fmovm.x		&0x01,-(%sp)		# save result to stack
	mov.w		(%sp),%d0		# fetch new exponent
	add.l		&0xc,%sp		# clear result from stack
	andi.l		&0x7fff,%d0		# strip sign
	sub.l		(%sp),%d0		# add scale factor
	cmp.l		%d0,(tbl_fdiv_ovfl2.b,%pc,%d1.w*4)
	blt.b		fdiv_no_ovfl
	mov.l		(%sp)+,%d0

fdiv_ovfl_tst:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fdiv_ovfl_ena		# yes

fdiv_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6) 	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass prec:rnd
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

fdiv_ovfl_ena:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# is precision extended?
	bne.b		fdiv_ovfl_ena_sd	# no, do sgl or dbl

fdiv_ovfl_ena_cont:
	fmovm.x		&0x80,FP_SCR0(%a6)	# move result to stack

	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.w		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	subi.l		&0x6000,%d1		# subtract bias
	andi.w		&0x7fff,%d1		# clear sign bit
	andi.w		&0x8000,%d2		# keep old sign
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.b		fdiv_ovfl_dis

fdiv_ovfl_ena_sd:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst operand

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# keep rnd mode
	fmov.l		%d1,%fpcr		# set FPCR

	fdiv.x		FP_SCR0(%a6),%fp0	# execute divide

	fmov.l		&0x0,%fpcr		# clear FPCR
	bra.b		fdiv_ovfl_ena_cont

fdiv_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		&rz_mode*0x10,%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fdiv.x		FP_SCR0(%a6),%fp0	# execute divide

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fdiv_unfl_ena		# yes

fdiv_unfl_dis:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result

	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# 'Z' may have been set
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts

#
# UNFL is enabled. 
#
fdiv_unfl_ena:
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# is precision extended?
	bne.b		fdiv_unfl_ena_sd	# no, sgl or dbl

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

fdiv_unfl_ena_cont:
	fmov.l		&0x0,%fpsr		# clear FPSR

	fdiv.x		FP_SCR0(%a6),%fp1	# execute divide

	fmov.l		&0x0,%fpcr		# clear FPCR

	fmovm.x		&0x40,FP_SCR0(%a6)	# save result to stack
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factoer
	addi.l		&0x6000,%d1		# add bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exp
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.w		fdiv_unfl_dis

fdiv_unfl_ena_sd:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# use only rnd mode
	fmov.l		%d1,%fpcr		# set FPCR

	bra.b		fdiv_unfl_ena_cont

#
# the divide operation MAY underflow:
#
fdiv_may_unfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fdiv.x		FP_SCR0(%a6),%fp0	# execute divide

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x1		# is |result| > 1.b?
	fbgt.w		fdiv_normal_exit	# no; no underflow occurred
	fblt.w		fdiv_unfl		# yes; underflow occurred

#
# we still don't know if underflow occurred. result is ~ equal to 1. but,
# we don't know if the result was an underflow that rounded up to a 1
# or a normalized number that rounded down to a 1. so, redo the entire 
# operation using RZ as the rounding mode to see what the pre-rounded 
# result is. this case should be relatively rare.
#
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op into fp1

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# keep rnd prec
	ori.b		&rz_mode*0x10,%d1	# insert RZ

	fmov.l		%d1,%fpcr		# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fdiv.x		FP_SCR0(%a6),%fp1	# execute divide

	fmov.l		&0x0,%fpcr		# clear FPCR
	fabs.x		%fp1			# make absolute value
	fcmp.b		%fp1,&0x1		# is |result| < 1.b?
	fbge.w		fdiv_normal_exit	# no; no underflow occurred
	bra.w		fdiv_unfl		# yes; underflow occurred

############################################################################

#
# Divide: inputs are not both normalized; what are they?
#
fdiv_not_norm:
	mov.w		(tbl_fdiv_op.b,%pc,%d1.w*2),%d1
	jmp		(tbl_fdiv_op.b,%pc,%d1.w*1)

	swbeg		&48
tbl_fdiv_op:
	short		fdiv_norm	- tbl_fdiv_op # NORM / NORM
	short		fdiv_inf_load	- tbl_fdiv_op # NORM / ZERO
	short		fdiv_zero_load	- tbl_fdiv_op # NORM / INF
	short		fdiv_res_qnan	- tbl_fdiv_op # NORM / QNAN
	short		fdiv_norm	- tbl_fdiv_op # NORM / DENORM
	short		fdiv_res_snan	- tbl_fdiv_op # NORM / SNAN
	short		tbl_fdiv_op	- tbl_fdiv_op #
	short		tbl_fdiv_op	- tbl_fdiv_op #

	short		fdiv_zero_load	- tbl_fdiv_op # ZERO / NORM
	short		fdiv_res_operr	- tbl_fdiv_op # ZERO / ZERO
	short		fdiv_zero_load	- tbl_fdiv_op # ZERO / INF
	short		fdiv_res_qnan	- tbl_fdiv_op # ZERO / QNAN
	short		fdiv_zero_load	- tbl_fdiv_op # ZERO / DENORM
	short		fdiv_res_snan	- tbl_fdiv_op # ZERO / SNAN
	short		tbl_fdiv_op	- tbl_fdiv_op #
	short		tbl_fdiv_op	- tbl_fdiv_op #

	short		fdiv_inf_dst	- tbl_fdiv_op # INF / NORM
	short		fdiv_inf_dst	- tbl_fdiv_op # INF / ZERO
	short		fdiv_res_operr	- tbl_fdiv_op # INF / INF
	short		fdiv_res_qnan	- tbl_fdiv_op # INF / QNAN
	short		fdiv_inf_dst	- tbl_fdiv_op # INF / DENORM
	short		fdiv_res_snan	- tbl_fdiv_op # INF / SNAN
	short		tbl_fdiv_op	- tbl_fdiv_op #
	short		tbl_fdiv_op	- tbl_fdiv_op #

	short		fdiv_res_qnan	- tbl_fdiv_op # QNAN / NORM
	short		fdiv_res_qnan	- tbl_fdiv_op # QNAN / ZERO
	short		fdiv_res_qnan	- tbl_fdiv_op # QNAN / INF
	short		fdiv_res_qnan	- tbl_fdiv_op # QNAN / QNAN
	short		fdiv_res_qnan	- tbl_fdiv_op # QNAN / DENORM
	short		fdiv_res_snan	- tbl_fdiv_op # QNAN / SNAN
	short		tbl_fdiv_op	- tbl_fdiv_op #
	short		tbl_fdiv_op	- tbl_fdiv_op #

	short		fdiv_norm	- tbl_fdiv_op # DENORM / NORM
	short		fdiv_inf_load	- tbl_fdiv_op # DENORM / ZERO
	short		fdiv_zero_load	- tbl_fdiv_op # DENORM / INF
	short		fdiv_res_qnan	- tbl_fdiv_op # DENORM / QNAN
	short		fdiv_norm	- tbl_fdiv_op # DENORM / DENORM
	short		fdiv_res_snan	- tbl_fdiv_op # DENORM / SNAN
	short		tbl_fdiv_op	- tbl_fdiv_op #
	short		tbl_fdiv_op	- tbl_fdiv_op #

	short		fdiv_res_snan	- tbl_fdiv_op # SNAN / NORM
	short		fdiv_res_snan	- tbl_fdiv_op # SNAN / ZERO
	short		fdiv_res_snan	- tbl_fdiv_op # SNAN / INF
	short		fdiv_res_snan	- tbl_fdiv_op # SNAN / QNAN
	short		fdiv_res_snan	- tbl_fdiv_op # SNAN / DENORM
	short		fdiv_res_snan	- tbl_fdiv_op # SNAN / SNAN
	short		tbl_fdiv_op	- tbl_fdiv_op #
	short		tbl_fdiv_op	- tbl_fdiv_op #

fdiv_res_qnan:
	bra.l		res_qnan
fdiv_res_snan:
	bra.l		res_snan
fdiv_res_operr:
	bra.l		res_operr

	global		fdiv_zero_load		# global for fsgldiv
fdiv_zero_load:
	mov.b		SRC_EX(%a0),%d0		# result sign is exclusive
	mov.b		DST_EX(%a1),%d1		# or of input signs.
	eor.b		%d0,%d1
	bpl.b		fdiv_zero_load_p	# result is positive
	fmov.s		&0x80000000,%fp0	# load a -ZERO
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6)	# set Z/N
	rts
fdiv_zero_load_p:
	fmov.s		&0x00000000,%fp0	# load a +ZERO
	mov.b		&z_bmask,FPSR_CC(%a6)	# set Z
	rts

#
# The destination was In Range and the source was a ZERO. The result,
# therefore, is an INF w/ the proper sign.
# So, determine the sign and return a new INF (w/ the j-bit cleared).
#
	global		fdiv_inf_load		# global for fsgldiv
fdiv_inf_load:
	ori.w		&dz_mask+adz_mask,2+USER_FPSR(%a6) # no; set DZ/ADZ
	mov.b		SRC_EX(%a0),%d0		# load both signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d0,%d1
	bpl.b		fdiv_inf_load_p		# result is positive
	fmov.s		&0xff800000,%fp0	# make result -INF
	mov.b		&inf_bmask+neg_bmask,FPSR_CC(%a6) # set INF/N
	rts
fdiv_inf_load_p:
	fmov.s		&0x7f800000,%fp0	# make result +INF
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set INF
	rts

#
# The destination was an INF w/ an In Range or ZERO source, the result is 
# an INF w/ the proper sign. 
# The 68881/882 returns the destination INF w/ the new sign(if the j-bit of the
# dst INF is set, then then j-bit of the result INF is also set).
#
	global		fdiv_inf_dst		# global for fsgldiv
fdiv_inf_dst:
	mov.b		DST_EX(%a1),%d0		# load both signs
	mov.b		SRC_EX(%a0),%d1
	eor.b		%d0,%d1
	bpl.b		fdiv_inf_dst_p		# result is positive

	fmovm.x		DST(%a1),&0x80		# return result in fp0
	fabs.x		%fp0			# clear sign bit
	fneg.x		%fp0			# set sign bit
	mov.b		&inf_bmask+neg_bmask,FPSR_CC(%a6) # set INF/NEG
	rts

fdiv_inf_dst_p:
	fmovm.x		DST(%a1),&0x80		# return result in fp0
	fabs.x		%fp0			# return positive INF
	mov.b		&inf_bmask,FPSR_CC(%a6) # set INF
	rts

#########################################################################
# XDEF ****************************************************************	#
#	fneg(): emulates the fneg instruction				#
#	fsneg(): emulates the fsneg instruction				#
#	fdneg(): emulates the fdneg instruction				#
#									#
# XREF ****************************************************************	#
# 	norm() - normalize a denorm to provide EXOP			#
#	scale_to_zero_src() - scale sgl/dbl source exponent		#
#	ovf_res() - return default overflow result			#
#	unf_res() - return default underflow result			#
# 	res_qnan_1op() - return QNAN result				#
#	res_snan_1op() - return SNAN result				#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	d0 = rnd prec,mode						#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
#	Handle NANs, zeroes, and infinities as special cases. Separate	#
# norms/denorms into ext/sgl/dbl precisions. Extended precision can be	#
# emulated by simply setting sign bit. Sgl/dbl operands must be scaled	#
# and an actual fneg performed to see if overflow/underflow would have	#
# occurred. If so, return default underflow/overflow result. Else,	#
# scale the result exponent and return result. FPSR gets set based on	#
# the result value.							#
#									#
#########################################################################

	global		fsneg
fsneg:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl precision
	bra.b		fneg

	global		fdneg
fdneg:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl prec

	global		fneg
fneg:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info
	mov.b		STAG(%a6),%d1
	bne.w		fneg_not_norm		# optimize on non-norm input
		
#
# NEGATE SIGN : norms and denorms ONLY!
#
fneg_norm:
	andi.b		&0xc0,%d0		# is precision extended?
	bne.w		fneg_not_ext		# no; go handle sgl or dbl

#
# precision selected is extended. so...we can not get an underflow
# or overflow because of rounding to the correct precision. so...
# skip the scaling and unscaling...
#
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	mov.w		SRC_EX(%a0),%d0
	eori.w		&0x8000,%d0		# negate sign
	bpl.b		fneg_norm_load		# sign is positive
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
fneg_norm_load:
	mov.w		%d0,FP_SCR0_EX(%a6)
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

#
# for an extended precision DENORM, the UNFL exception bit is set
# the accrued bit is NOT set in this instance(no inexactness!)
#
fneg_denorm:
	andi.b		&0xc0,%d0		# is precision extended?
	bne.b		fneg_not_ext		# no; go handle sgl or dbl

	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	mov.w		SRC_EX(%a0),%d0
	eori.w		&0x8000,%d0		# negate sign
	bpl.b		fneg_denorm_done	# no
	mov.b		&neg_bmask,FPSR_CC(%a6)	# yes, set 'N' ccode bit
fneg_denorm_done:
	mov.w		%d0,FP_SCR0_EX(%a6)
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0

	btst		&unfl_bit,FPCR_ENABLE(%a6) # is UNFL enabled?
	bne.b		fneg_ext_unfl_ena	# yes
	rts

#
# the input is an extended DENORM and underflow is enabled in the FPCR.
# normalize the mantissa and add the bias of 0x6000 to the resulting negative
# exponent and insert back into the operand.
#
fneg_ext_unfl_ena:
	lea		FP_SCR0(%a6),%a0	# pass: ptr to operand
	bsr.l		norm			# normalize result
	neg.w		%d0			# new exponent = -(shft val)
	addi.w		&0x6000,%d0		# add new bias to exponent
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch old sign,exp
	andi.w		&0x8000,%d1	 	# keep old sign
	andi.w		&0x7fff,%d0		# clear sign position
	or.w		%d1,%d0			# concat old sign, new exponent
	mov.w		%d0,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	rts

#
# operand is either single or double
#
fneg_not_ext:
	cmpi.b		%d0,&s_mode*0x10	# separate sgl/dbl prec
	bne.b		fneg_dbl

#
# operand is to be rounded to single precision
#
fneg_sgl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3f80	# will move in underflow?
	bge.w		fneg_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x407e	# will move in overflow?
	beq.w		fneg_sd_may_ovfl	# maybe; go check
	blt.w		fneg_sd_ovfl		# yes; go handle overflow

#
# operand will NOT overflow or underflow when moved in to the fp reg file
#
fneg_sd_normal:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fneg.x		FP_SCR0(%a6),%fp0	# perform negation

	fmov.l		%fpsr,%d1		# save FPSR
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fneg_sd_normal_exit:
	mov.l		%d2,-(%sp)		# save d2
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result
	mov.w		FP_SCR0_EX(%a6),%d1	# load sgn,exp
	mov.w		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	andi.w		&0x8000,%d2		# keep old sign
	or.w		%d1,%d2			# concat old sign,new exp
	mov.w		%d2,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

#
# operand is to be rounded to double precision
#
fneg_dbl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3c00	# will move in underflow?
	bge.b		fneg_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x43fe	# will move in overflow?
	beq.w		fneg_sd_may_ovfl	# maybe; go check
	blt.w		fneg_sd_ovfl		# yes; go handle overflow
	bra.w		fneg_sd_normal		# no; ho handle normalized op

#
# operand WILL underflow when moved in to the fp register file
#
fneg_sd_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	eori.b		&0x80,FP_SCR0_EX(%a6)	# negate sign	
	bpl.b		fneg_sd_unfl_tst
	bset		&neg_bit,FPSR_CC(%a6)	# set 'N' ccode bit

# if underflow or inexact is enabled, go calculate EXOP first.
fneg_sd_unfl_tst:
	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fneg_sd_unfl_ena	# yes

fneg_sd_unfl_dis:
	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# unf_res may have set 'Z'
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts	

#
# operand will underflow AND underflow is enabled. 
# therefore, we must return the result rounded to extended precision.
#
fneg_sd_unfl_ena:
	mov.l		FP_SCR0_HI(%a6),FP_SCR1_HI(%a6)
	mov.l		FP_SCR0_LO(%a6),FP_SCR1_LO(%a6)
	mov.w		FP_SCR0_EX(%a6),%d1	# load current exponent

	mov.l		%d2,-(%sp)		# save d2
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# subtract scale factor
	addi.l		&0x6000,%d1		# add new bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat new sign,new exp
	mov.w		%d1,FP_SCR1_EX(%a6)	# insert new exp
	fmovm.x		FP_SCR1(%a6),&0x40	# return EXOP in fp1
	mov.l		(%sp)+,%d2		# restore d2
	bra.b		fneg_sd_unfl_dis

#
# operand WILL overflow.
#
fneg_sd_ovfl:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fneg.x		FP_SCR0(%a6),%fp0	# perform negation

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# save FPSR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fneg_sd_ovfl_tst:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fneg_sd_ovfl_ena	# yes

#
# OVFL is not enabled; therefore, we must create the default result by
# calling ovf_res().
#
fneg_sd_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass: prec,mode
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

#
# OVFL is enabled.
# the INEX2 bit has already been updated by the round to the correct precision.
# now, round to extended(and don't alter the FPSR).
#
fneg_sd_ovfl_ena:
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	subi.l		&0x6000,%d1		# subtract bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat sign,exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	mov.l		(%sp)+,%d2		# restore d2
	bra.b		fneg_sd_ovfl_dis

#
# the move in MAY underflow. so...
#
fneg_sd_may_ovfl:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fneg.x		FP_SCR0(%a6),%fp0	# perform negation

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x2		# is |result| >= 2.b?
	fbge.w		fneg_sd_ovfl_tst	# yes; overflow has occurred

# no, it didn't overflow; we have correct result
	bra.w		fneg_sd_normal_exit

##########################################################################

#
# input is not normalized; what is it?
#
fneg_not_norm:
	cmpi.b		%d1,&DENORM		# weed out DENORM
	beq.w		fneg_denorm
	cmpi.b		%d1,&SNAN		# weed out SNAN
	beq.l		res_snan_1op
	cmpi.b		%d1,&QNAN		# weed out QNAN
	beq.l		res_qnan_1op

#
# do the fneg; at this point, only possible ops are ZERO and INF.
# use fneg to determine ccodes.
# prec:mode should be zero at this point but it won't affect answer anyways.
#
	fneg.x		SRC_EX(%a0),%fp0	# do fneg
	fmov.l		%fpsr,%d0
	rol.l		&0x8,%d0		# put ccodes in lo byte
	mov.b		%d0,FPSR_CC(%a6)	# insert correct ccodes
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	ftst(): emulates the ftest instruction				#
#									#
# XREF ****************************************************************	#
# 	res{s,q}nan_1op() - set NAN result for monadic instruction	#
#									#
# INPUT ***************************************************************	#
# 	a0 = pointer to extended precision source operand		#
#									#
# OUTPUT **************************************************************	#
#	none								#
#									#
# ALGORITHM ***********************************************************	#
# 	Check the source operand tag (STAG) and set the FPCR according	#
# to the operand type and sign.						#
#									#
#########################################################################

	global		ftst
ftst:
	mov.b		STAG(%a6),%d1
	bne.b		ftst_not_norm		# optimize on non-norm input
		
#
# Norm:
#
ftst_norm:
	tst.b		SRC_EX(%a0)		# is operand negative?
	bmi.b		ftst_norm_m		# yes
	rts
ftst_norm_m:
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
	rts

#
# input is not normalized; what is it?
#
ftst_not_norm:
	cmpi.b		%d1,&ZERO		# weed out ZERO
	beq.b		ftst_zero
	cmpi.b		%d1,&INF		# weed out INF
	beq.b		ftst_inf
	cmpi.b		%d1,&SNAN		# weed out SNAN
	beq.l		res_snan_1op
	cmpi.b		%d1,&QNAN		# weed out QNAN
	beq.l		res_qnan_1op

#
# Denorm:
#
ftst_denorm:
	tst.b		SRC_EX(%a0)		# is operand negative?
	bmi.b		ftst_denorm_m		# yes
	rts
ftst_denorm_m:
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
	rts

#
# Infinity:
#
ftst_inf:
	tst.b		SRC_EX(%a0)		# is operand negative?
	bmi.b		ftst_inf_m		# yes
ftst_inf_p:
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set 'I' ccode bit
	rts
ftst_inf_m:
	mov.b		&inf_bmask+neg_bmask,FPSR_CC(%a6) # set 'I','N' ccode bits
	rts
	
#
# Zero:
#
ftst_zero:
	tst.b		SRC_EX(%a0)		# is operand negative?
	bmi.b		ftst_zero_m		# yes
ftst_zero_p:
	mov.b		&z_bmask,FPSR_CC(%a6)	# set 'N' ccode bit
	rts
ftst_zero_m:
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6)	# set 'Z','N' ccode bits
	rts

#########################################################################
# XDEF ****************************************************************	#
#	fint(): emulates the fint instruction				#
#									#
# XREF ****************************************************************	#
#	res_{s,q}nan_1op() - set NAN result for monadic operation	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	d0 = round precision/mode					#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#									#
# ALGORITHM ***********************************************************	#
# 	Separate according to operand type. Unnorms don't pass through 	#
# here. For norms, load the rounding mode/prec, execute a "fint", then 	#
# store the resulting FPSR bits.					#
# 	For denorms, force the j-bit to a one and do the same as for	#
# norms. Denorms are so low that the answer will either be a zero or a 	#
# one.									#
# 	For zeroes/infs/NANs, return the same while setting the FPSR	#
# as appropriate.							#
#									#
#########################################################################

	global		fint
fint:
	mov.b		STAG(%a6),%d1
	bne.b		fint_not_norm		# optimize on non-norm input
		
#
# Norm:
#
fint_norm:
	andi.b		&0x30,%d0		# set prec = ext

	fmov.l		%d0,%fpcr		# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fint.x 		SRC(%a0),%fp0		# execute fint

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d0		# save FPSR
	or.l		%d0,USER_FPSR(%a6)	# set exception bits

	rts

#
# input is not normalized; what is it?
#
fint_not_norm:
	cmpi.b		%d1,&ZERO		# weed out ZERO
	beq.b		fint_zero
	cmpi.b		%d1,&INF		# weed out INF
	beq.b		fint_inf
	cmpi.b		%d1,&DENORM		# weed out DENORM
	beq.b		fint_denorm
	cmpi.b		%d1,&SNAN		# weed out SNAN
	beq.l		res_snan_1op
	bra.l		res_qnan_1op		# weed out QNAN

#
# Denorm:
#
# for DENORMs, the result will be either (+/-)ZERO or (+/-)1.
# also, the INEX2 and AINEX exception bits will be set.
# so, we could either set these manually or force the DENORM
# to a very small NORM and ship it to the NORM routine.
# I do the latter.
#
fint_denorm:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6) # copy sign, zero exp
	mov.b		&0x80,FP_SCR0_HI(%a6)	# force DENORM ==> small NORM
	lea		FP_SCR0(%a6),%a0
	bra.b		fint_norm

#
# Zero:
#
fint_zero:
	tst.b		SRC_EX(%a0)		# is ZERO negative?
	bmi.b		fint_zero_m		# yes
fint_zero_p:
	fmov.s		&0x00000000,%fp0	# return +ZERO in fp0
	mov.b		&z_bmask,FPSR_CC(%a6)	# set 'Z' ccode bit
	rts
fint_zero_m:
	fmov.s		&0x80000000,%fp0	# return -ZERO in fp0
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6) # set 'Z','N' ccode bits
	rts

#
# Infinity:
#
fint_inf:
	fmovm.x		SRC(%a0),&0x80		# return result in fp0
	tst.b		SRC_EX(%a0)		# is INF negative?
	bmi.b		fint_inf_m		# yes
fint_inf_p:
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set 'I' ccode bit
	rts
fint_inf_m:
	mov.b		&inf_bmask+neg_bmask,FPSR_CC(%a6) # set 'N','I' ccode bits
	rts

#########################################################################
# XDEF ****************************************************************	#
#	fintrz(): emulates the fintrz instruction			#
#									#
# XREF ****************************************************************	#
#	res_{s,q}nan_1op() - set NAN result for monadic operation	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	d0 = round precision/mode					#
#									#
# OUTPUT **************************************************************	#
# 	fp0 = result							#
#									#
# ALGORITHM ***********************************************************	#
#	Separate according to operand type. Unnorms don't pass through	#
# here. For norms, load the rounding mode/prec, execute a "fintrz", 	#
# then store the resulting FPSR bits.					#
# 	For denorms, force the j-bit to a one and do the same as for	#
# norms. Denorms are so low that the answer will either be a zero or a	#
# one.									#
# 	For zeroes/infs/NANs, return the same while setting the FPSR	#
# as appropriate.							#
#									#
#########################################################################

	global		fintrz
fintrz:
	mov.b		STAG(%a6),%d1
	bne.b		fintrz_not_norm		# optimize on non-norm input
		
#
# Norm:
#
fintrz_norm:
	fmov.l		&0x0,%fpsr		# clear FPSR

	fintrz.x	SRC(%a0),%fp0		# execute fintrz

	fmov.l		%fpsr,%d0		# save FPSR
	or.l		%d0,USER_FPSR(%a6)	# set exception bits

	rts

#
# input is not normalized; what is it?
#
fintrz_not_norm:
	cmpi.b		%d1,&ZERO		# weed out ZERO
	beq.b		fintrz_zero
	cmpi.b		%d1,&INF		# weed out INF
	beq.b		fintrz_inf
	cmpi.b		%d1,&DENORM		# weed out DENORM
	beq.b		fintrz_denorm
	cmpi.b		%d1,&SNAN		# weed out SNAN
	beq.l		res_snan_1op
	bra.l		res_qnan_1op		# weed out QNAN

#
# Denorm:
#
# for DENORMs, the result will be (+/-)ZERO.
# also, the INEX2 and AINEX exception bits will be set.
# so, we could either set these manually or force the DENORM
# to a very small NORM and ship it to the NORM routine.
# I do the latter.
#
fintrz_denorm:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6) # copy sign, zero exp
	mov.b		&0x80,FP_SCR0_HI(%a6)	# force DENORM ==> small NORM
	lea		FP_SCR0(%a6),%a0
	bra.b		fintrz_norm

#
# Zero:
#
fintrz_zero:
	tst.b		SRC_EX(%a0)		# is ZERO negative?
	bmi.b		fintrz_zero_m		# yes
fintrz_zero_p:
	fmov.s		&0x00000000,%fp0	# return +ZERO in fp0
	mov.b		&z_bmask,FPSR_CC(%a6)	# set 'Z' ccode bit
	rts
fintrz_zero_m:
	fmov.s		&0x80000000,%fp0	# return -ZERO in fp0
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6) # set 'Z','N' ccode bits
	rts

#
# Infinity:
#
fintrz_inf:
	fmovm.x		SRC(%a0),&0x80		# return result in fp0
	tst.b		SRC_EX(%a0)		# is INF negative?
	bmi.b		fintrz_inf_m		# yes
fintrz_inf_p:
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set 'I' ccode bit
	rts
fintrz_inf_m:
	mov.b		&inf_bmask+neg_bmask,FPSR_CC(%a6) # set 'N','I' ccode bits
	rts

#########################################################################
# XDEF ****************************************************************	#
#	fabs():  emulates the fabs instruction				#
#	fsabs(): emulates the fsabs instruction				#
#	fdabs(): emulates the fdabs instruction				#
#									#
# XREF **************************************************************** #
#	norm() - normalize denorm mantissa to provide EXOP		#
#	scale_to_zero_src() - make exponent. = 0; get scale factor	#
#	unf_res() - calculate underflow result				#
#	ovf_res() - calculate overflow result				#
#	res_{s,q}nan_1op() - set NAN result for monadic operation	#
#									#
# INPUT *************************************************************** #
#	a0 = pointer to extended precision source operand		#
#	d0 = rnd precision/mode						#
#									#
# OUTPUT ************************************************************** #
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
#	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms into extended, single, and double precision. 			#
# 	Simply clear sign for extended precision norm. Ext prec denorm	#
# gets an EXOP created for it since it's an underflow.			#
#	Double and single precision can overflow and underflow. First,	#
# scale the operand such that the exponent is zero. Perform an "fabs"	#
# using the correct rnd mode/prec. Check to see if the original 	#
# exponent would take an exception. If so, use unf_res() or ovf_res()	#
# to calculate the default result. Also, create the EXOP for the	#
# exceptional case. If no exception should occur, insert the correct 	#
# result exponent and return.						#
# 	Unnorms don't pass through here.				#
#									#
#########################################################################

	global		fsabs
fsabs:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl precision
	bra.b		fabs

	global		fdabs
fdabs:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl precision

	global		fabs
fabs:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info
	mov.b		STAG(%a6),%d1
	bne.w		fabs_not_norm		# optimize on non-norm input
		
#
# ABSOLUTE VALUE: norms and denorms ONLY!
#
fabs_norm:
	andi.b		&0xc0,%d0		# is precision extended?
	bne.b		fabs_not_ext		# no; go handle sgl or dbl

#
# precision selected is extended. so...we can not get an underflow
# or overflow because of rounding to the correct precision. so...
# skip the scaling and unscaling...
#
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	mov.w		SRC_EX(%a0),%d1
	bclr		&15,%d1			# force absolute value
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert exponent
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

#
# for an extended precision DENORM, the UNFL exception bit is set
# the accrued bit is NOT set in this instance(no inexactness!)
#
fabs_denorm:
	andi.b		&0xc0,%d0		# is precision extended?
	bne.b		fabs_not_ext		# no

	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	mov.w		SRC_EX(%a0),%d0
	bclr		&15,%d0			# clear sign
	mov.w		%d0,FP_SCR0_EX(%a6)	# insert exponent

	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0

	btst		&unfl_bit,FPCR_ENABLE(%a6) # is UNFL enabled?
	bne.b		fabs_ext_unfl_ena
	rts

#
# the input is an extended DENORM and underflow is enabled in the FPCR.
# normalize the mantissa and add the bias of 0x6000 to the resulting negative
# exponent and insert back into the operand.
#
fabs_ext_unfl_ena:
	lea		FP_SCR0(%a6),%a0	# pass: ptr to operand
	bsr.l		norm			# normalize result
	neg.w		%d0			# new exponent = -(shft val)
	addi.w		&0x6000,%d0		# add new bias to exponent
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch old sign,exp
	andi.w		&0x8000,%d1		# keep old sign
	andi.w		&0x7fff,%d0		# clear sign position
	or.w		%d1,%d0			# concat old sign, new exponent
	mov.w		%d0,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	rts

#
# operand is either single or double
#
fabs_not_ext:
	cmpi.b		%d0,&s_mode*0x10	# separate sgl/dbl prec
	bne.b		fabs_dbl

#
# operand is to be rounded to single precision
#
fabs_sgl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3f80	# will move in underflow?
	bge.w		fabs_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x407e	# will move in overflow?
	beq.w		fabs_sd_may_ovfl	# maybe; go check
	blt.w		fabs_sd_ovfl		# yes; go handle overflow

#
# operand will NOT overflow or underflow when moved in to the fp reg file
#
fabs_sd_normal:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fabs.x		FP_SCR0(%a6),%fp0	# perform absolute

	fmov.l		%fpsr,%d1		# save FPSR
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fabs_sd_normal_exit:
	mov.l		%d2,-(%sp)		# save d2
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result
	mov.w		FP_SCR0_EX(%a6),%d1	# load sgn,exp
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	andi.w		&0x8000,%d2		# keep old sign
	or.w		%d1,%d2			# concat old sign,new exp
	mov.w		%d2,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

#
# operand is to be rounded to double precision
#
fabs_dbl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3c00	# will move in underflow?
	bge.b		fabs_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x43fe	# will move in overflow?
	beq.w		fabs_sd_may_ovfl	# maybe; go check
	blt.w		fabs_sd_ovfl		# yes; go handle overflow
	bra.w		fabs_sd_normal		# no; ho handle normalized op

#
# operand WILL underflow when moved in to the fp register file
#
fabs_sd_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	bclr		&0x7,FP_SCR0_EX(%a6)	# force absolute value

# if underflow or inexact is enabled, go calculate EXOP first.
	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fabs_sd_unfl_ena	# yes

fabs_sd_unfl_dis:
	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set possible 'Z' ccode
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts	

#
# operand will underflow AND underflow is enabled. 
# therefore, we must return the result rounded to extended precision.
#
fabs_sd_unfl_ena:
	mov.l		FP_SCR0_HI(%a6),FP_SCR1_HI(%a6)
	mov.l		FP_SCR0_LO(%a6),FP_SCR1_LO(%a6)
	mov.w		FP_SCR0_EX(%a6),%d1	# load current exponent

	mov.l		%d2,-(%sp)		# save d2
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# subtract scale factor
	addi.l		&0x6000,%d1		# add new bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat new sign,new exp
	mov.w		%d1,FP_SCR1_EX(%a6)	# insert new exp
	fmovm.x		FP_SCR1(%a6),&0x40	# return EXOP in fp1
	mov.l		(%sp)+,%d2		# restore d2
	bra.b		fabs_sd_unfl_dis

#
# operand WILL overflow.
#
fabs_sd_ovfl:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fabs.x		FP_SCR0(%a6),%fp0	# perform absolute

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# save FPSR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fabs_sd_ovfl_tst:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fabs_sd_ovfl_ena	# yes

#
# OVFL is not enabled; therefore, we must create the default result by
# calling ovf_res().
#
fabs_sd_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass: prec,mode
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

#
# OVFL is enabled.
# the INEX2 bit has already been updated by the round to the correct precision.
# now, round to extended(and don't alter the FPSR).
#
fabs_sd_ovfl_ena:
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	subi.l		&0x6000,%d1		# subtract bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat sign,exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	mov.l		(%sp)+,%d2		# restore d2
	bra.b		fabs_sd_ovfl_dis

#
# the move in MAY underflow. so...
#
fabs_sd_may_ovfl:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fabs.x		FP_SCR0(%a6),%fp0	# perform absolute

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x2		# is |result| >= 2.b?
	fbge.w		fabs_sd_ovfl_tst	# yes; overflow has occurred

# no, it didn't overflow; we have correct result
	bra.w		fabs_sd_normal_exit

##########################################################################

#
# input is not normalized; what is it?
#
fabs_not_norm:
	cmpi.b		%d1,&DENORM		# weed out DENORM
	beq.w		fabs_denorm
	cmpi.b		%d1,&SNAN		# weed out SNAN
	beq.l		res_snan_1op
	cmpi.b		%d1,&QNAN		# weed out QNAN
	beq.l		res_qnan_1op

	fabs.x		SRC(%a0),%fp0		# force absolute value

	cmpi.b		%d1,&INF		# weed out INF
	beq.b		fabs_inf
fabs_zero:
	mov.b		&z_bmask,FPSR_CC(%a6)	# set 'Z' ccode bit
	rts
fabs_inf:
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set 'I' ccode bit
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	fcmp(): fp compare op routine					#
#									#
# XREF ****************************************************************	#
# 	res_qnan() - return QNAN result					#
#	res_snan() - return SNAN result					#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	a1 = pointer to extended precision destination operand		#
#	d0 = round prec/mode						#
#									#
# OUTPUT ************************************************************** #
#	None								#
#									#
# ALGORITHM ***********************************************************	#
# 	Handle NANs and denorms as special cases. For everything else,	#
# just use the actual fcmp instruction to produce the correct condition	#
# codes.								#
#									#
#########################################################################

	global		fcmp
fcmp:
	clr.w		%d1
	mov.b		DTAG(%a6),%d1
	lsl.b		&0x3,%d1
	or.b		STAG(%a6),%d1
	bne.b		fcmp_not_norm		# optimize on non-norm input
		
#
# COMPARE FP OPs : NORMs, ZEROs, INFs, and "corrected" DENORMs
#
fcmp_norm:
	fmovm.x		DST(%a1),&0x80		# load dst op

	fcmp.x 		%fp0,SRC(%a0)		# do compare

	fmov.l		%fpsr,%d0		# save FPSR
	rol.l		&0x8,%d0		# extract ccode bits
	mov.b		%d0,FPSR_CC(%a6)	# set ccode bits(no exc bits are set)

	rts

#
# fcmp: inputs are not both normalized; what are they?
#
fcmp_not_norm:
	mov.w		(tbl_fcmp_op.b,%pc,%d1.w*2),%d1
	jmp		(tbl_fcmp_op.b,%pc,%d1.w*1)

	swbeg		&48
tbl_fcmp_op:
	short		fcmp_norm	- tbl_fcmp_op # NORM - NORM
	short		fcmp_norm	- tbl_fcmp_op # NORM - ZERO
	short		fcmp_norm	- tbl_fcmp_op # NORM - INF
	short		fcmp_res_qnan	- tbl_fcmp_op # NORM - QNAN
	short		fcmp_nrm_dnrm 	- tbl_fcmp_op # NORM - DENORM
	short		fcmp_res_snan	- tbl_fcmp_op # NORM - SNAN
	short		tbl_fcmp_op	- tbl_fcmp_op #
	short		tbl_fcmp_op	- tbl_fcmp_op #

	short		fcmp_norm	- tbl_fcmp_op # ZERO - NORM
	short		fcmp_norm	- tbl_fcmp_op # ZERO - ZERO
	short		fcmp_norm	- tbl_fcmp_op # ZERO - INF
	short		fcmp_res_qnan	- tbl_fcmp_op # ZERO - QNAN
	short		fcmp_dnrm_s	- tbl_fcmp_op # ZERO - DENORM
	short		fcmp_res_snan	- tbl_fcmp_op # ZERO - SNAN
	short		tbl_fcmp_op	- tbl_fcmp_op #
	short		tbl_fcmp_op	- tbl_fcmp_op #

	short		fcmp_norm	- tbl_fcmp_op # INF - NORM
	short		fcmp_norm	- tbl_fcmp_op # INF - ZERO
	short		fcmp_norm	- tbl_fcmp_op # INF - INF
	short		fcmp_res_qnan	- tbl_fcmp_op # INF - QNAN
	short		fcmp_dnrm_s	- tbl_fcmp_op # INF - DENORM
	short		fcmp_res_snan	- tbl_fcmp_op # INF - SNAN
	short		tbl_fcmp_op	- tbl_fcmp_op #
	short		tbl_fcmp_op	- tbl_fcmp_op #

	short		fcmp_res_qnan	- tbl_fcmp_op # QNAN - NORM
	short		fcmp_res_qnan	- tbl_fcmp_op # QNAN - ZERO
	short		fcmp_res_qnan	- tbl_fcmp_op # QNAN - INF
	short		fcmp_res_qnan	- tbl_fcmp_op # QNAN - QNAN
	short		fcmp_res_qnan	- tbl_fcmp_op # QNAN - DENORM
	short		fcmp_res_snan	- tbl_fcmp_op # QNAN - SNAN
	short		tbl_fcmp_op	- tbl_fcmp_op #
	short		tbl_fcmp_op	- tbl_fcmp_op #

	short		fcmp_dnrm_nrm	- tbl_fcmp_op # DENORM - NORM
	short		fcmp_dnrm_d	- tbl_fcmp_op # DENORM - ZERO
	short		fcmp_dnrm_d	- tbl_fcmp_op # DENORM - INF
	short		fcmp_res_qnan	- tbl_fcmp_op # DENORM - QNAN
	short		fcmp_dnrm_sd	- tbl_fcmp_op # DENORM - DENORM
	short		fcmp_res_snan	- tbl_fcmp_op # DENORM - SNAN
	short		tbl_fcmp_op	- tbl_fcmp_op #
	short		tbl_fcmp_op	- tbl_fcmp_op #

	short		fcmp_res_snan	- tbl_fcmp_op # SNAN - NORM
	short		fcmp_res_snan	- tbl_fcmp_op # SNAN - ZERO
	short		fcmp_res_snan	- tbl_fcmp_op # SNAN - INF
	short		fcmp_res_snan	- tbl_fcmp_op # SNAN - QNAN
	short		fcmp_res_snan	- tbl_fcmp_op # SNAN - DENORM
	short		fcmp_res_snan	- tbl_fcmp_op # SNAN - SNAN
	short		tbl_fcmp_op	- tbl_fcmp_op #
	short		tbl_fcmp_op	- tbl_fcmp_op #

# unlike all other functions for QNAN and SNAN, fcmp does NOT set the
# 'N' bit for a negative QNAN or SNAN input so we must squelch it here.
fcmp_res_qnan:
	bsr.l		res_qnan
	andi.b		&0xf7,FPSR_CC(%a6)
	rts
fcmp_res_snan:
	bsr.l		res_snan
	andi.b		&0xf7,FPSR_CC(%a6)
	rts

#
# DENORMs are a little more difficult. 
# If you have a 2 DENORMs, then you can just force the j-bit to a one 
# and use the fcmp_norm routine.
# If you have a DENORM and an INF or ZERO, just force the DENORM's j-bit to a one
# and use the fcmp_norm routine.
# If you have a DENORM and a NORM with opposite signs, then use fcmp_norm, also.
# But with a DENORM and a NORM of the same sign, the neg bit is set if the
# (1) signs are (+) and the DENORM is the dst or
# (2) signs are (-) and the DENORM is the src
#

fcmp_dnrm_s:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),%d0
	bset		&31,%d0			# DENORM src; make into small norm
	mov.l		%d0,FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	lea		FP_SCR0(%a6),%a0
	bra.w		fcmp_norm

fcmp_dnrm_d:
	mov.l		DST_EX(%a1),FP_SCR0_EX(%a6)
	mov.l		DST_HI(%a1),%d0
	bset		&31,%d0			# DENORM src; make into small norm
	mov.l		%d0,FP_SCR0_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR0_LO(%a6)
	lea		FP_SCR0(%a6),%a1
	bra.w		fcmp_norm

fcmp_dnrm_sd:
	mov.w		DST_EX(%a1),FP_SCR1_EX(%a6)
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		DST_HI(%a1),%d0
	bset		&31,%d0			# DENORM dst; make into small norm
	mov.l		%d0,FP_SCR1_HI(%a6)
	mov.l		SRC_HI(%a0),%d0
	bset		&31,%d0			# DENORM dst; make into small norm
	mov.l		%d0,FP_SCR0_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	lea		FP_SCR1(%a6),%a1
	lea		FP_SCR0(%a6),%a0
	bra.w		fcmp_norm	

fcmp_nrm_dnrm:
	mov.b		SRC_EX(%a0),%d0		# determine if like signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d0,%d1
	bmi.w		fcmp_dnrm_s

# signs are the same, so must determine the answer ourselves.
	tst.b		%d0			# is src op negative?
	bmi.b		fcmp_nrm_dnrm_m		# yes
	rts
fcmp_nrm_dnrm_m:
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'Z' ccode bit
	rts

fcmp_dnrm_nrm:
	mov.b		SRC_EX(%a0),%d0		# determine if like signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d0,%d1
	bmi.w		fcmp_dnrm_d

# signs are the same, so must determine the answer ourselves.
	tst.b		%d0			# is src op negative?
	bpl.b		fcmp_dnrm_nrm_m		# no
	rts
fcmp_dnrm_nrm_m:
	mov.b		&neg_bmask,FPSR_CC(%a6)	# set 'Z' ccode bit
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	fsglmul(): emulates the fsglmul instruction			#
#									#
# XREF ****************************************************************	#
#	scale_to_zero_src() - scale src exponent to zero		#
#	scale_to_zero_dst() - scale dst exponent to zero		#
#	unf_res4() - return default underflow result for sglop		#
#	ovf_res() - return default overflow result			#
# 	res_qnan() - return QNAN result					#
# 	res_snan() - return SNAN result					#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	a1 = pointer to extended precision destination operand		#
#	d0  rnd prec,mode						#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
#	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms/denorms into ext/sgl/dbl precision.				#
#	For norms/denorms, scale the exponents such that a multiply	#
# instruction won't cause an exception. Use the regular fsglmul to	#
# compute a result. Check if the regular operands would have taken	#
# an exception. If so, return the default overflow/underflow result	#
# and return the EXOP if exceptions are enabled. Else, scale the 	#
# result operand to the proper exponent.				#
#									#
#########################################################################

	global		fsglmul
fsglmul:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info

	clr.w		%d1
	mov.b		DTAG(%a6),%d1
	lsl.b		&0x3,%d1
	or.b		STAG(%a6),%d1

	bne.w		fsglmul_not_norm	# optimize on non-norm input

fsglmul_norm:
	mov.w		DST_EX(%a1),FP_SCR1_EX(%a6)
	mov.l		DST_HI(%a1),FP_SCR1_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	bsr.l		scale_to_zero_src	# scale exponent
	mov.l		%d0,-(%sp)		# save scale factor 1

	bsr.l		scale_to_zero_dst	# scale dst exponent

	add.l		(%sp)+,%d0		# SCALE_FACTOR = scale1 + scale2

	cmpi.l		%d0,&0x3fff-0x7ffe 	# would result ovfl?
	beq.w		fsglmul_may_ovfl	# result may rnd to overflow
	blt.w		fsglmul_ovfl		# result will overflow

	cmpi.l		%d0,&0x3fff+0x0001 	# would result unfl?
	beq.w		fsglmul_may_unfl	# result may rnd to no unfl
	bgt.w		fsglmul_unfl		# result will underflow

fsglmul_normal:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsglmul.x	FP_SCR0(%a6),%fp0	# execute sgl multiply

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fsglmul_normal_exit:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# load {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

fsglmul_ovfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsglmul.x	FP_SCR0(%a6),%fp0	# execute sgl multiply

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fsglmul_ovfl_tst:

# save setting this until now because this is where fsglmul_may_ovfl may jump in
	or.l		&ovfl_inx_mask, USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fsglmul_ovfl_ena	# yes

fsglmul_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass prec:rnd
	andi.b		&0x30,%d0		# force prec = ext
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

fsglmul_ovfl_ena:
	fmovm.x		&0x80,FP_SCR0(%a6)	# move result to stack

	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	subi.l		&0x6000,%d1		# subtract bias
	andi.w		&0x7fff,%d1
	andi.w		&0x8000,%d2		# keep old sign
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.b		fsglmul_ovfl_dis

fsglmul_may_ovfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsglmul.x	FP_SCR0(%a6),%fp0	# execute sgl multiply
	
	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x2		# is |result| >= 2.b?
	fbge.w		fsglmul_ovfl_tst	# yes; overflow has occurred
	
# no, it didn't overflow; we have correct result
	bra.w		fsglmul_normal_exit

fsglmul_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		&rz_mode*0x10,%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsglmul.x	FP_SCR0(%a6),%fp0	# execute sgl multiply

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fsglmul_unfl_ena	# yes

fsglmul_unfl_dis:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result

	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res4		# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# 'Z' bit may have been set
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts

#
# UNFL is enabled. 
#
fsglmul_unfl_ena:
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsglmul.x	FP_SCR0(%a6),%fp1	# execute sgl multiply	

	fmov.l		&0x0,%fpcr		# clear FPCR

	fmovm.x		&0x40,FP_SCR0(%a6)	# save result to stack
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	addi.l		&0x6000,%d1		# add bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.w		fsglmul_unfl_dis

fsglmul_may_unfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsglmul.x	FP_SCR0(%a6),%fp0	# execute sgl multiply	

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x2		# is |result| > 2.b?
	fbgt.w		fsglmul_normal_exit	# no; no underflow occurred
	fblt.w		fsglmul_unfl		# yes; underflow occurred

#
# we still don't know if underflow occurred. result is ~ equal to 2. but,
# we don't know if the result was an underflow that rounded up to a 2 or
# a normalized number that rounded down to a 2. so, redo the entire operation
# using RZ as the rounding mode to see what the pre-rounded result is.
# this case should be relatively rare.
#
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op into fp1

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# keep rnd prec
	ori.b		&rz_mode*0x10,%d1	# insert RZ
	
	fmov.l		%d1,%fpcr		# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsglmul.x	FP_SCR0(%a6),%fp1	# execute sgl multiply	

	fmov.l		&0x0,%fpcr		# clear FPCR
	fabs.x		%fp1			# make absolute value
	fcmp.b		%fp1,&0x2		# is |result| < 2.b?
	fbge.w		fsglmul_normal_exit	# no; no underflow occurred
	bra.w		fsglmul_unfl		# yes, underflow occurred

##############################################################################

#
# Single Precision Multiply: inputs are not both normalized; what are they?
#
fsglmul_not_norm:
	mov.w		(tbl_fsglmul_op.b,%pc,%d1.w*2),%d1
	jmp		(tbl_fsglmul_op.b,%pc,%d1.w*1)

	swbeg		&48
tbl_fsglmul_op:
	short		fsglmul_norm		- tbl_fsglmul_op # NORM x NORM
	short		fsglmul_zero		- tbl_fsglmul_op # NORM x ZERO
	short		fsglmul_inf_src		- tbl_fsglmul_op # NORM x INF
	short		fsglmul_res_qnan	- tbl_fsglmul_op # NORM x QNAN
	short		fsglmul_norm		- tbl_fsglmul_op # NORM x DENORM
	short		fsglmul_res_snan	- tbl_fsglmul_op # NORM x SNAN
	short		tbl_fsglmul_op		- tbl_fsglmul_op #
	short		tbl_fsglmul_op		- tbl_fsglmul_op #

	short		fsglmul_zero		- tbl_fsglmul_op # ZERO x NORM
	short		fsglmul_zero		- tbl_fsglmul_op # ZERO x ZERO
	short		fsglmul_res_operr	- tbl_fsglmul_op # ZERO x INF
	short		fsglmul_res_qnan	- tbl_fsglmul_op # ZERO x QNAN
	short		fsglmul_zero		- tbl_fsglmul_op # ZERO x DENORM
	short		fsglmul_res_snan	- tbl_fsglmul_op # ZERO x SNAN
	short		tbl_fsglmul_op		- tbl_fsglmul_op #
	short		tbl_fsglmul_op		- tbl_fsglmul_op #

	short		fsglmul_inf_dst		- tbl_fsglmul_op # INF x NORM
	short		fsglmul_res_operr	- tbl_fsglmul_op # INF x ZERO
	short		fsglmul_inf_dst		- tbl_fsglmul_op # INF x INF
	short		fsglmul_res_qnan	- tbl_fsglmul_op # INF x QNAN
	short		fsglmul_inf_dst		- tbl_fsglmul_op # INF x DENORM
	short		fsglmul_res_snan	- tbl_fsglmul_op # INF x SNAN
	short		tbl_fsglmul_op		- tbl_fsglmul_op #
	short		tbl_fsglmul_op		- tbl_fsglmul_op #

	short		fsglmul_res_qnan	- tbl_fsglmul_op # QNAN x NORM
	short		fsglmul_res_qnan	- tbl_fsglmul_op # QNAN x ZERO
	short		fsglmul_res_qnan	- tbl_fsglmul_op # QNAN x INF
	short		fsglmul_res_qnan	- tbl_fsglmul_op # QNAN x QNAN
	short		fsglmul_res_qnan	- tbl_fsglmul_op # QNAN x DENORM
	short		fsglmul_res_snan	- tbl_fsglmul_op # QNAN x SNAN
	short		tbl_fsglmul_op		- tbl_fsglmul_op #
	short		tbl_fsglmul_op		- tbl_fsglmul_op #

	short		fsglmul_norm		- tbl_fsglmul_op # NORM x NORM
	short		fsglmul_zero		- tbl_fsglmul_op # NORM x ZERO
	short		fsglmul_inf_src		- tbl_fsglmul_op # NORM x INF
	short		fsglmul_res_qnan	- tbl_fsglmul_op # NORM x QNAN
	short		fsglmul_norm		- tbl_fsglmul_op # NORM x DENORM
	short		fsglmul_res_snan	- tbl_fsglmul_op # NORM x SNAN
	short		tbl_fsglmul_op		- tbl_fsglmul_op #
	short		tbl_fsglmul_op		- tbl_fsglmul_op #

	short		fsglmul_res_snan	- tbl_fsglmul_op # SNAN x NORM
	short		fsglmul_res_snan	- tbl_fsglmul_op # SNAN x ZERO
	short		fsglmul_res_snan	- tbl_fsglmul_op # SNAN x INF
	short		fsglmul_res_snan	- tbl_fsglmul_op # SNAN x QNAN
	short		fsglmul_res_snan	- tbl_fsglmul_op # SNAN x DENORM
	short		fsglmul_res_snan	- tbl_fsglmul_op # SNAN x SNAN
	short		tbl_fsglmul_op		- tbl_fsglmul_op #
	short		tbl_fsglmul_op		- tbl_fsglmul_op #

fsglmul_res_operr:
	bra.l		res_operr
fsglmul_res_snan:
	bra.l		res_snan
fsglmul_res_qnan:
	bra.l		res_qnan
fsglmul_zero:
	bra.l		fmul_zero
fsglmul_inf_src:
	bra.l		fmul_inf_src
fsglmul_inf_dst:
	bra.l		fmul_inf_dst

#########################################################################
# XDEF ****************************************************************	#
# 	fsgldiv(): emulates the fsgldiv instruction			#
#									#
# XREF ****************************************************************	#
#	scale_to_zero_src() - scale src exponent to zero		#
#	scale_to_zero_dst() - scale dst exponent to zero		#
#	unf_res4() - return default underflow result for sglop		#
#	ovf_res() - return default overflow result			#
# 	res_qnan() - return QNAN result					#
# 	res_snan() - return SNAN result					#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	a1 = pointer to extended precision destination operand		#
#	d0  rnd prec,mode						#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
#	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms/denorms into ext/sgl/dbl precision.				#
#	For norms/denorms, scale the exponents such that a divide	#
# instruction won't cause an exception. Use the regular fsgldiv to	#
# compute a result. Check if the regular operands would have taken	#
# an exception. If so, return the default overflow/underflow result	#
# and return the EXOP if exceptions are enabled. Else, scale the 	#
# result operand to the proper exponent.				#
#									#
#########################################################################

	global		fsgldiv
fsgldiv:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info

	clr.w		%d1
	mov.b		DTAG(%a6),%d1
	lsl.b		&0x3,%d1
	or.b		STAG(%a6),%d1		# combine src tags

	bne.w		fsgldiv_not_norm	# optimize on non-norm input
		
#
# DIVIDE: NORMs and DENORMs ONLY!
#
fsgldiv_norm:
	mov.w		DST_EX(%a1),FP_SCR1_EX(%a6)
	mov.l		DST_HI(%a1),FP_SCR1_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	bsr.l		scale_to_zero_src	# calculate scale factor 1
	mov.l		%d0,-(%sp)		# save scale factor 1

	bsr.l		scale_to_zero_dst	# calculate scale factor 2

	neg.l		(%sp)			# S.F. = scale1 - scale2
	add.l		%d0,(%sp)

	mov.w		2+L_SCR3(%a6),%d1	# fetch precision,mode
	lsr.b		&0x6,%d1
	mov.l		(%sp)+,%d0
	cmpi.l		%d0,&0x3fff-0x7ffe
	ble.w		fsgldiv_may_ovfl

	cmpi.l		%d0,&0x3fff-0x0000 	# will result underflow?
	beq.w		fsgldiv_may_unfl	# maybe
	bgt.w		fsgldiv_unfl		# yes; go handle underflow

fsgldiv_normal:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# save FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsgldiv.x	FP_SCR0(%a6),%fp0	# perform sgl divide

	fmov.l		%fpsr,%d1		# save FPSR
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fsgldiv_normal_exit:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store result on stack
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# load {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

fsgldiv_may_ovfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# set FPSR

	fsgldiv.x	FP_SCR0(%a6),%fp0	# execute divide

	fmov.l		%fpsr,%d1
	fmov.l		&0x0,%fpcr

	or.l		%d1,USER_FPSR(%a6)	# save INEX,N

	fmovm.x		&0x01,-(%sp)		# save result to stack
	mov.w		(%sp),%d1		# fetch new exponent
	add.l		&0xc,%sp		# clear result
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	cmp.l		%d1,&0x7fff		# did divide overflow?
	blt.b		fsgldiv_normal_exit

fsgldiv_ovfl_tst:
	or.w		&ovfl_inx_mask,2+USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fsgldiv_ovfl_ena	# yes

fsgldiv_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6) 	# is result negative
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass prec:rnd
	andi.b		&0x30,%d0		# kill precision
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

fsgldiv_ovfl_ena:
	fmovm.x		&0x80,FP_SCR0(%a6)	# move result to stack

	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	subi.l		&0x6000,%d1		# subtract new bias
	andi.w		&0x7fff,%d1		# clear ms bit
	or.w		%d2,%d1			# concat old sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.b		fsgldiv_ovfl_dis

fsgldiv_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		&rz_mode*0x10,%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsgldiv.x	FP_SCR0(%a6),%fp0	# execute sgl divide

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fsgldiv_unfl_ena	# yes

fsgldiv_unfl_dis:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result

	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res4		# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# 'Z' bit may have been set
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts

#
# UNFL is enabled. 
#
fsgldiv_unfl_ena:
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsgldiv.x	FP_SCR0(%a6),%fp1	# execute sgl divide

	fmov.l		&0x0,%fpcr		# clear FPCR

	fmovm.x		&0x40,FP_SCR0(%a6)	# save result to stack
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	addi.l		&0x6000,%d1		# add bias
	andi.w		&0x7fff,%d1		# clear top bit
	or.w		%d2,%d1			# concat old sign, new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.b		fsgldiv_unfl_dis

#
# the divide operation MAY underflow:
#
fsgldiv_may_unfl:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsgldiv.x	FP_SCR0(%a6),%fp0	# execute sgl divide

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fabs.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x1		# is |result| > 1.b?
	fbgt.w		fsgldiv_normal_exit	# no; no underflow occurred
	fblt.w		fsgldiv_unfl		# yes; underflow occurred

#
# we still don't know if underflow occurred. result is ~ equal to 1. but,
# we don't know if the result was an underflow that rounded up to a 1
# or a normalized number that rounded down to a 1. so, redo the entire 
# operation using RZ as the rounding mode to see what the pre-rounded 
# result is. this case should be relatively rare.
#
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op into %fp1

	clr.l		%d1			# clear scratch register
	ori.b		&rz_mode*0x10,%d1	# force RZ rnd mode

	fmov.l		%d1,%fpcr		# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsgldiv.x	FP_SCR0(%a6),%fp1	# execute sgl divide

	fmov.l		&0x0,%fpcr		# clear FPCR
	fabs.x		%fp1			# make absolute value
	fcmp.b		%fp1,&0x1		# is |result| < 1.b?
	fbge.w		fsgldiv_normal_exit	# no; no underflow occurred
	bra.w		fsgldiv_unfl		# yes; underflow occurred

############################################################################

#
# Divide: inputs are not both normalized; what are they?
#
fsgldiv_not_norm:
	mov.w		(tbl_fsgldiv_op.b,%pc,%d1.w*2),%d1
	jmp		(tbl_fsgldiv_op.b,%pc,%d1.w*1)

	swbeg		&48
tbl_fsgldiv_op:
	short		fsgldiv_norm		- tbl_fsgldiv_op # NORM / NORM
	short		fsgldiv_inf_load	- tbl_fsgldiv_op # NORM / ZERO
	short		fsgldiv_zero_load	- tbl_fsgldiv_op # NORM / INF
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # NORM / QNAN
	short		fsgldiv_norm		- tbl_fsgldiv_op # NORM / DENORM
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # NORM / SNAN
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #

	short		fsgldiv_zero_load	- tbl_fsgldiv_op # ZERO / NORM
	short		fsgldiv_res_operr	- tbl_fsgldiv_op # ZERO / ZERO
	short		fsgldiv_zero_load	- tbl_fsgldiv_op # ZERO / INF
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # ZERO / QNAN
	short		fsgldiv_zero_load	- tbl_fsgldiv_op # ZERO / DENORM
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # ZERO / SNAN
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #

	short		fsgldiv_inf_dst		- tbl_fsgldiv_op # INF / NORM
	short		fsgldiv_inf_dst		- tbl_fsgldiv_op # INF / ZERO
	short		fsgldiv_res_operr	- tbl_fsgldiv_op # INF / INF
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # INF / QNAN
	short		fsgldiv_inf_dst		- tbl_fsgldiv_op # INF / DENORM
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # INF / SNAN
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #

	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # QNAN / NORM
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # QNAN / ZERO
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # QNAN / INF
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # QNAN / QNAN
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # QNAN / DENORM
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # QNAN / SNAN
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #

	short		fsgldiv_norm		- tbl_fsgldiv_op # DENORM / NORM
	short		fsgldiv_inf_load	- tbl_fsgldiv_op # DENORM / ZERO
	short		fsgldiv_zero_load	- tbl_fsgldiv_op # DENORM / INF
	short		fsgldiv_res_qnan	- tbl_fsgldiv_op # DENORM / QNAN
	short		fsgldiv_norm		- tbl_fsgldiv_op # DENORM / DENORM
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # DENORM / SNAN
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #

	short		fsgldiv_res_snan	- tbl_fsgldiv_op # SNAN / NORM
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # SNAN / ZERO
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # SNAN / INF
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # SNAN / QNAN
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # SNAN / DENORM
	short		fsgldiv_res_snan	- tbl_fsgldiv_op # SNAN / SNAN
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #
	short		tbl_fsgldiv_op		- tbl_fsgldiv_op #

fsgldiv_res_qnan:
	bra.l		res_qnan
fsgldiv_res_snan:
	bra.l		res_snan
fsgldiv_res_operr:
	bra.l		res_operr
fsgldiv_inf_load:
	bra.l		fdiv_inf_load
fsgldiv_zero_load:
	bra.l		fdiv_zero_load
fsgldiv_inf_dst:
	bra.l		fdiv_inf_dst

#########################################################################
# XDEF ****************************************************************	#
#	fadd(): emulates the fadd instruction				#
#	fsadd(): emulates the fadd instruction				#
#	fdadd(): emulates the fdadd instruction				#
#									#
# XREF ****************************************************************	#
# 	addsub_scaler2() - scale the operands so they won't take exc	#
#	ovf_res() - return default overflow result			#
#	unf_res() - return default underflow result			#
#	res_qnan() - set QNAN result					#
# 	res_snan() - set SNAN result					#
#	res_operr() - set OPERR result					#
#	scale_to_zero_src() - set src operand exponent equal to zero	#
#	scale_to_zero_dst() - set dst operand exponent equal to zero	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
# 	a1 = pointer to extended precision destination operand		#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
# 	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms into extended, single, and double precision.			#
#	Do addition after scaling exponents such that exception won't	#
# occur. Then, check result exponent to see if exception would have	#
# occurred. If so, return default result and maybe EXOP. Else, insert	#
# the correct result exponent and return. Set FPSR bits as appropriate.	#
#									#
#########################################################################

	global		fsadd
fsadd:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl prec
	bra.b		fadd

	global		fdadd
fdadd:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl prec

	global		fadd
fadd:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info

	clr.w		%d1
	mov.b		DTAG(%a6),%d1
	lsl.b		&0x3,%d1
	or.b		STAG(%a6),%d1		# combine src tags

	bne.w		fadd_not_norm		# optimize on non-norm input

#
# ADD: norms and denorms
#
fadd_norm:
	bsr.l		addsub_scaler2		# scale exponents

fadd_zero_entry:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fadd.x		FP_SCR0(%a6),%fp0	# execute add

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# fetch INEX2,N,Z

	or.l		%d1,USER_FPSR(%a6)	# save exc and ccode bits

	fbeq.w		fadd_zero_exit		# if result is zero, end now

	mov.l		%d2,-(%sp)		# save d2

	fmovm.x		&0x01,-(%sp)		# save result to stack

	mov.w		2+L_SCR3(%a6),%d1
	lsr.b		&0x6,%d1

	mov.w		(%sp),%d2		# fetch new sign, exp
	andi.l		&0x7fff,%d2		# strip sign
	sub.l		%d0,%d2			# add scale factor

	cmp.l		%d2,(tbl_fadd_ovfl.b,%pc,%d1.w*4) # is it an overflow?
	bge.b		fadd_ovfl		# yes

	cmp.l		%d2,(tbl_fadd_unfl.b,%pc,%d1.w*4) # is it an underflow?
	blt.w		fadd_unfl		# yes
	beq.w		fadd_may_unfl		# maybe; go find out

fadd_normal:
	mov.w		(%sp),%d1
	andi.w		&0x8000,%d1		# keep sign
	or.w		%d2,%d1			# concat sign,new exp
	mov.w		%d1,(%sp)		# insert new exponent

	fmovm.x		(%sp)+,&0x80		# return result in fp0

	mov.l		(%sp)+,%d2		# restore d2
	rts

fadd_zero_exit:
#	fmov.s		&0x00000000,%fp0	# return zero in fp0
	rts

tbl_fadd_ovfl:
	long		0x7fff			# ext ovfl
	long		0x407f			# sgl ovfl
	long		0x43ff			# dbl ovfl

tbl_fadd_unfl:
	long	        0x0000			# ext unfl
	long		0x3f81			# sgl unfl
	long		0x3c01			# dbl unfl

fadd_ovfl:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fadd_ovfl_ena		# yes

	add.l		&0xc,%sp
fadd_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass prec:rnd
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	mov.l		(%sp)+,%d2		# restore d2
	rts

fadd_ovfl_ena:
	mov.b		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# is precision extended?
	bne.b		fadd_ovfl_ena_sd	# no; prec = sgl or dbl

fadd_ovfl_ena_cont:
	mov.w		(%sp),%d1
	andi.w		&0x8000,%d1		# keep sign
	subi.l		&0x6000,%d2		# add extra bias
	andi.w		&0x7fff,%d2
	or.w		%d2,%d1			# concat sign,new exp
	mov.w		%d1,(%sp)		# insert new exponent

	fmovm.x		(%sp)+,&0x40		# return EXOP in fp1
	bra.b		fadd_ovfl_dis

fadd_ovfl_ena_sd:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# keep rnd mode
	fmov.l		%d1,%fpcr		# set FPCR

	fadd.x		FP_SCR0(%a6),%fp0	# execute add

	fmov.l		&0x0,%fpcr		# clear FPCR

	add.l		&0xc,%sp
	fmovm.x		&0x01,-(%sp)
	bra.b		fadd_ovfl_ena_cont

fadd_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	add.l		&0xc,%sp

	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		&rz_mode*0x10,%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fadd.x		FP_SCR0(%a6),%fp0	# execute add

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# save status

	or.l		%d1,USER_FPSR(%a6)	# save INEX,N

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fadd_unfl_ena		# yes

fadd_unfl_dis:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result

	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# 'Z' bit may have been set
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	mov.l		(%sp)+,%d2		# restore d2
	rts

fadd_unfl_ena:
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# is precision extended?
	bne.b		fadd_unfl_ena_sd	# no; sgl or dbl

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

fadd_unfl_ena_cont:
	fmov.l		&0x0,%fpsr		# clear FPSR

	fadd.x		FP_SCR0(%a6),%fp1	# execute multiply

	fmov.l		&0x0,%fpcr		# clear FPCR

	fmovm.x		&0x40,FP_SCR0(%a6)	# save result to stack
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	addi.l		&0x6000,%d1		# add new bias
	andi.w		&0x7fff,%d1		# clear top bit
	or.w		%d2,%d1			# concat sign,new exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.w		fadd_unfl_dis

fadd_unfl_ena_sd:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# use only rnd mode
	fmov.l		%d1,%fpcr		# set FPCR

	bra.b		fadd_unfl_ena_cont

#
# result is equal to the smallest normalized number in the selected precision
# if the precision is extended, this result could not have come from an 
# underflow that rounded up.
#
fadd_may_unfl:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1
	beq.w		fadd_normal		# yes; no underflow occurred

	mov.l		0x4(%sp),%d1		# extract hi(man)
	cmpi.l		%d1,&0x80000000		# is hi(man) = 0x80000000?
	bne.w		fadd_normal		# no; no underflow occurred

	tst.l		0x8(%sp)		# is lo(man) = 0x0?
	bne.w		fadd_normal		# no; no underflow occurred

	btst		&inex2_bit,FPSR_EXCEPT(%a6) # is INEX2 set?
	beq.w		fadd_normal		# no; no underflow occurred

#
# ok, so now the result has a exponent equal to the smallest normalized
# exponent for the selected precision. also, the mantissa is equal to
# 0x8000000000000000 and this mantissa is the result of rounding non-zero
# g,r,s. 
# now, we must determine whether the pre-rounded result was an underflow
# rounded "up" or a normalized number rounded "down".
# so, we do this be re-executing the add using RZ as the rounding mode and
# seeing if the new result is smaller or equal to the current result.
#
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op into fp1

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# keep rnd prec
	ori.b		&rz_mode*0x10,%d1	# insert rnd mode
	fmov.l		%d1,%fpcr		# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fadd.x		FP_SCR0(%a6),%fp1	# execute add

	fmov.l		&0x0,%fpcr		# clear FPCR

	fabs.x		%fp0			# compare absolute values
	fabs.x		%fp1
	fcmp.x		%fp0,%fp1		# is first result > second?

	fbgt.w		fadd_unfl		# yes; it's an underflow
	bra.w		fadd_normal		# no; it's not an underflow

##########################################################################

#
# Add: inputs are not both normalized; what are they?
#
fadd_not_norm:
	mov.w		(tbl_fadd_op.b,%pc,%d1.w*2),%d1
	jmp		(tbl_fadd_op.b,%pc,%d1.w*1)

	swbeg		&48
tbl_fadd_op:
	short		fadd_norm	- tbl_fadd_op # NORM + NORM
	short		fadd_zero_src	- tbl_fadd_op # NORM + ZERO
	short		fadd_inf_src	- tbl_fadd_op # NORM + INF
	short		fadd_res_qnan	- tbl_fadd_op # NORM + QNAN
	short		fadd_norm	- tbl_fadd_op # NORM + DENORM
	short		fadd_res_snan	- tbl_fadd_op # NORM + SNAN
	short		tbl_fadd_op	- tbl_fadd_op #
	short		tbl_fadd_op	- tbl_fadd_op #

	short		fadd_zero_dst	- tbl_fadd_op # ZERO + NORM
	short		fadd_zero_2	- tbl_fadd_op # ZERO + ZERO
	short		fadd_inf_src	- tbl_fadd_op # ZERO + INF
	short		fadd_res_qnan	- tbl_fadd_op # NORM + QNAN
	short		fadd_zero_dst	- tbl_fadd_op # ZERO + DENORM
	short		fadd_res_snan	- tbl_fadd_op # NORM + SNAN
	short		tbl_fadd_op	- tbl_fadd_op #
	short		tbl_fadd_op	- tbl_fadd_op #

	short		fadd_inf_dst	- tbl_fadd_op # INF + NORM
	short		fadd_inf_dst	- tbl_fadd_op # INF + ZERO
	short		fadd_inf_2	- tbl_fadd_op # INF + INF
	short		fadd_res_qnan	- tbl_fadd_op # NORM + QNAN
	short		fadd_inf_dst	- tbl_fadd_op # INF + DENORM
	short		fadd_res_snan	- tbl_fadd_op # NORM + SNAN
	short		tbl_fadd_op	- tbl_fadd_op #
	short		tbl_fadd_op	- tbl_fadd_op #

	short		fadd_res_qnan	- tbl_fadd_op # QNAN + NORM
	short		fadd_res_qnan	- tbl_fadd_op # QNAN + ZERO
	short		fadd_res_qnan	- tbl_fadd_op # QNAN + INF
	short		fadd_res_qnan	- tbl_fadd_op # QNAN + QNAN
	short		fadd_res_qnan	- tbl_fadd_op # QNAN + DENORM
	short		fadd_res_snan	- tbl_fadd_op # QNAN + SNAN
	short		tbl_fadd_op	- tbl_fadd_op #
	short		tbl_fadd_op	- tbl_fadd_op #

	short		fadd_norm	- tbl_fadd_op # DENORM + NORM
	short		fadd_zero_src	- tbl_fadd_op # DENORM + ZERO
	short		fadd_inf_src	- tbl_fadd_op # DENORM + INF
	short		fadd_res_qnan	- tbl_fadd_op # NORM + QNAN
	short		fadd_norm	- tbl_fadd_op # DENORM + DENORM
	short		fadd_res_snan	- tbl_fadd_op # NORM + SNAN
	short		tbl_fadd_op	- tbl_fadd_op #
	short		tbl_fadd_op	- tbl_fadd_op #

	short		fadd_res_snan	- tbl_fadd_op # SNAN + NORM
	short		fadd_res_snan	- tbl_fadd_op # SNAN + ZERO
	short		fadd_res_snan	- tbl_fadd_op # SNAN + INF
	short		fadd_res_snan	- tbl_fadd_op # SNAN + QNAN
	short		fadd_res_snan	- tbl_fadd_op # SNAN + DENORM
	short		fadd_res_snan	- tbl_fadd_op # SNAN + SNAN
	short		tbl_fadd_op	- tbl_fadd_op #
	short		tbl_fadd_op	- tbl_fadd_op #

fadd_res_qnan:
	bra.l		res_qnan
fadd_res_snan:
	bra.l		res_snan

#
# both operands are ZEROes
#
fadd_zero_2:
	mov.b		SRC_EX(%a0),%d0		# are the signs opposite
	mov.b		DST_EX(%a1),%d1
	eor.b		%d0,%d1
	bmi.w		fadd_zero_2_chk_rm	# weed out (-ZERO)+(+ZERO)

# the signs are the same. so determine whether they are positive or negative
# and return the appropriately signed zero.
	tst.b		%d0			# are ZEROes positive or negative?
	bmi.b		fadd_zero_rm		# negative
	fmov.s		&0x00000000,%fp0	# return +ZERO
	mov.b		&z_bmask,FPSR_CC(%a6)	# set Z
	rts
	
#
# the ZEROes have opposite signs:
# - therefore, we return +ZERO if the rounding modes are RN,RZ, or RP.
# - -ZERO is returned in the case of RM.
#
fadd_zero_2_chk_rm:
	mov.b		3+L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# extract rnd mode
	cmpi.b		%d1,&rm_mode*0x10	# is rnd mode == RM?
	beq.b		fadd_zero_rm		# yes
	fmov.s		&0x00000000,%fp0	# return +ZERO
	mov.b		&z_bmask,FPSR_CC(%a6)	# set Z
	rts

fadd_zero_rm:
	fmov.s		&0x80000000,%fp0	# return -ZERO
	mov.b		&neg_bmask+z_bmask,FPSR_CC(%a6) # set NEG/Z
	rts

#
# one operand is a ZERO and the other is a DENORM or NORM. scale
# the DENORM or NORM and jump to the regular fadd routine.
#
fadd_zero_dst:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# scale the operand
	clr.w		FP_SCR1_EX(%a6)
	clr.l		FP_SCR1_HI(%a6)
	clr.l		FP_SCR1_LO(%a6)
	bra.w		fadd_zero_entry		# go execute fadd

fadd_zero_src:
	mov.w		DST_EX(%a1),FP_SCR1_EX(%a6)
	mov.l		DST_HI(%a1),FP_SCR1_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)
	bsr.l		scale_to_zero_dst	# scale the operand
	clr.w		FP_SCR0_EX(%a6)
	clr.l		FP_SCR0_HI(%a6)
	clr.l		FP_SCR0_LO(%a6)
	bra.w		fadd_zero_entry		# go execute fadd

#
# both operands are INFs. an OPERR will result if the INFs have
# different signs. else, an INF of the same sign is returned
#
fadd_inf_2:
	mov.b		SRC_EX(%a0),%d0		# exclusive or the signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d1,%d0
	bmi.l		res_operr		# weed out (-INF)+(+INF)

# ok, so it's not an OPERR. but, we do have to remember to return the 
# src INF since that's where the 881/882 gets the j-bit from...

#
# operands are INF and one of {ZERO, INF, DENORM, NORM}
#
fadd_inf_src:
	fmovm.x		SRC(%a0),&0x80		# return src INF
	tst.b		SRC_EX(%a0)		# is INF positive?
	bpl.b		fadd_inf_done		# yes; we're done
	mov.b		&neg_bmask+inf_bmask,FPSR_CC(%a6) # set INF/NEG
	rts

#
# operands are INF and one of {ZERO, INF, DENORM, NORM}
#
fadd_inf_dst:
	fmovm.x		DST(%a1),&0x80		# return dst INF
	tst.b		DST_EX(%a1)		# is INF positive?
	bpl.b		fadd_inf_done		# yes; we're done
	mov.b		&neg_bmask+inf_bmask,FPSR_CC(%a6) # set INF/NEG
	rts

fadd_inf_done:
	mov.b		&inf_bmask,FPSR_CC(%a6) # set INF
	rts

#########################################################################
# XDEF ****************************************************************	#
#	fsub(): emulates the fsub instruction				#
#	fssub(): emulates the fssub instruction				#
#	fdsub(): emulates the fdsub instruction				#
#									#
# XREF ****************************************************************	#
# 	addsub_scaler2() - scale the operands so they won't take exc	#
#	ovf_res() - return default overflow result			#
#	unf_res() - return default underflow result			#
#	res_qnan() - set QNAN result					#
# 	res_snan() - set SNAN result					#
#	res_operr() - set OPERR result					#
#	scale_to_zero_src() - set src operand exponent equal to zero	#
#	scale_to_zero_dst() - set dst operand exponent equal to zero	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
# 	a1 = pointer to extended precision destination operand		#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
# 	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms into extended, single, and double precision.			#
#	Do subtraction after scaling exponents such that exception won't#
# occur. Then, check result exponent to see if exception would have	#
# occurred. If so, return default result and maybe EXOP. Else, insert	#
# the correct result exponent and return. Set FPSR bits as appropriate.	#
#									#
#########################################################################

	global		fssub
fssub:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl prec
	bra.b		fsub

	global		fdsub
fdsub:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl prec

	global		fsub
fsub:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info

	clr.w		%d1
	mov.b		DTAG(%a6),%d1
	lsl.b		&0x3,%d1
	or.b		STAG(%a6),%d1		# combine src tags

	bne.w		fsub_not_norm		# optimize on non-norm input

#
# SUB: norms and denorms
#
fsub_norm:
	bsr.l		addsub_scaler2		# scale exponents

fsub_zero_entry:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fsub.x		FP_SCR0(%a6),%fp0	# execute subtract

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# fetch INEX2, N, Z

	or.l		%d1,USER_FPSR(%a6)	# save exc and ccode bits

	fbeq.w		fsub_zero_exit		# if result zero, end now

	mov.l		%d2,-(%sp)		# save d2

	fmovm.x		&0x01,-(%sp)		# save result to stack

	mov.w		2+L_SCR3(%a6),%d1
	lsr.b		&0x6,%d1

	mov.w		(%sp),%d2		# fetch new exponent
	andi.l		&0x7fff,%d2		# strip sign
	sub.l		%d0,%d2			# add scale factor

	cmp.l		%d2,(tbl_fsub_ovfl.b,%pc,%d1.w*4) # is it an overflow?
	bge.b		fsub_ovfl		# yes

	cmp.l		%d2,(tbl_fsub_unfl.b,%pc,%d1.w*4) # is it an underflow?
	blt.w		fsub_unfl		# yes
	beq.w		fsub_may_unfl		# maybe; go find out

fsub_normal:
	mov.w		(%sp),%d1
	andi.w		&0x8000,%d1		# keep sign
	or.w		%d2,%d1			# insert new exponent
	mov.w		%d1,(%sp)		# insert new exponent

	fmovm.x		(%sp)+,&0x80		# return result in fp0

	mov.l		(%sp)+,%d2		# restore d2
	rts

fsub_zero_exit:
#	fmov.s		&0x00000000,%fp0	# return zero in fp0
	rts

tbl_fsub_ovfl:
	long		0x7fff			# ext ovfl
	long		0x407f			# sgl ovfl
	long		0x43ff			# dbl ovfl

tbl_fsub_unfl:
	long	        0x0000			# ext unfl
	long		0x3f81			# sgl unfl
	long		0x3c01			# dbl unfl

fsub_ovfl:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fsub_ovfl_ena		# yes

	add.l		&0xc,%sp
fsub_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass prec:rnd
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	mov.l		(%sp)+,%d2		# restore d2
	rts

fsub_ovfl_ena:
	mov.b		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# is precision extended?
	bne.b		fsub_ovfl_ena_sd	# no

fsub_ovfl_ena_cont:
	mov.w		(%sp),%d1		# fetch {sgn,exp}
	andi.w		&0x8000,%d1		# keep sign
	subi.l		&0x6000,%d2		# subtract new bias
	andi.w		&0x7fff,%d2		# clear top bit
	or.w		%d2,%d1			# concat sign,exp
	mov.w		%d1,(%sp)		# insert new exponent

	fmovm.x		(%sp)+,&0x40		# return EXOP in fp1
	bra.b		fsub_ovfl_dis

fsub_ovfl_ena_sd:
	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# clear rnd prec
	fmov.l		%d1,%fpcr		# set FPCR

	fsub.x		FP_SCR0(%a6),%fp0	# execute subtract

	fmov.l		&0x0,%fpcr		# clear FPCR

	add.l		&0xc,%sp
	fmovm.x		&0x01,-(%sp)
	bra.b		fsub_ovfl_ena_cont

fsub_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	add.l		&0xc,%sp

	fmovm.x		FP_SCR1(%a6),&0x80	# load dst op
	
	fmov.l		&rz_mode*0x10,%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsub.x		FP_SCR0(%a6),%fp0	# execute subtract

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# save status

	or.l		%d1,USER_FPSR(%a6)

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fsub_unfl_ena		# yes

fsub_unfl_dis:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result

	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# 'Z' may have been set
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	mov.l		(%sp)+,%d2		# restore d2
	rts

fsub_unfl_ena:
	fmovm.x		FP_SCR1(%a6),&0x40

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# is precision extended?
	bne.b		fsub_unfl_ena_sd	# no

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

fsub_unfl_ena_cont:
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsub.x		FP_SCR0(%a6),%fp1	# execute subtract

	fmov.l		&0x0,%fpcr		# clear FPCR

	fmovm.x		&0x40,FP_SCR0(%a6)	# store result to stack
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	addi.l		&0x6000,%d1		# subtract new bias
	andi.w		&0x7fff,%d1		# clear top bit
	or.w		%d2,%d1			# concat sgn,exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	bra.w		fsub_unfl_dis

fsub_unfl_ena_sd:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# clear rnd prec
	fmov.l		%d1,%fpcr		# set FPCR

	bra.b		fsub_unfl_ena_cont

#
# result is equal to the smallest normalized number in the selected precision
# if the precision is extended, this result could not have come from an 
# underflow that rounded up.
#
fsub_may_unfl:
	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# fetch rnd prec
	beq.w		fsub_normal		# yes; no underflow occurred

	mov.l		0x4(%sp),%d1
	cmpi.l		%d1,&0x80000000		# is hi(man) = 0x80000000?
	bne.w		fsub_normal		# no; no underflow occurred

	tst.l		0x8(%sp)		# is lo(man) = 0x0?
	bne.w		fsub_normal		# no; no underflow occurred

	btst		&inex2_bit,FPSR_EXCEPT(%a6) # is INEX2 set?
	beq.w		fsub_normal		# no; no underflow occurred

#
# ok, so now the result has a exponent equal to the smallest normalized
# exponent for the selected precision. also, the mantissa is equal to
# 0x8000000000000000 and this mantissa is the result of rounding non-zero
# g,r,s. 
# now, we must determine whether the pre-rounded result was an underflow
# rounded "up" or a normalized number rounded "down".
# so, we do this be re-executing the add using RZ as the rounding mode and
# seeing if the new result is smaller or equal to the current result.
#
	fmovm.x		FP_SCR1(%a6),&0x40	# load dst op into fp1

	mov.l		L_SCR3(%a6),%d1
	andi.b		&0xc0,%d1		# keep rnd prec
	ori.b		&rz_mode*0x10,%d1	# insert rnd mode
	fmov.l		%d1,%fpcr		# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsub.x		FP_SCR0(%a6),%fp1	# execute subtract

	fmov.l		&0x0,%fpcr		# clear FPCR

	fabs.x		%fp0			# compare absolute values
	fabs.x		%fp1
	fcmp.x		%fp0,%fp1		# is first result > second?

	fbgt.w		fsub_unfl		# yes; it's an underflow
	bra.w		fsub_normal		# no; it's not an underflow

##########################################################################

#
# Sub: inputs are not both normalized; what are they?
#
fsub_not_norm:
	mov.w		(tbl_fsub_op.b,%pc,%d1.w*2),%d1
	jmp		(tbl_fsub_op.b,%pc,%d1.w*1)

	swbeg		&48
tbl_fsub_op:
	short		fsub_norm	- tbl_fsub_op # NORM - NORM
	short		fsub_zero_src	- tbl_fsub_op # NORM - ZERO
	short		fsub_inf_src	- tbl_fsub_op # NORM - INF
	short		fsub_res_qnan	- tbl_fsub_op # NORM - QNAN
	short		fsub_norm	- tbl_fsub_op # NORM - DENORM
	short		fsub_res_snan	- tbl_fsub_op # NORM - SNAN
	short		tbl_fsub_op	- tbl_fsub_op #
	short		tbl_fsub_op	- tbl_fsub_op #

	short		fsub_zero_dst	- tbl_fsub_op # ZERO - NORM
	short		fsub_zero_2	- tbl_fsub_op # ZERO - ZERO
	short		fsub_inf_src	- tbl_fsub_op # ZERO - INF
	short		fsub_res_qnan	- tbl_fsub_op # NORM - QNAN
	short		fsub_zero_dst	- tbl_fsub_op # ZERO - DENORM
	short		fsub_res_snan	- tbl_fsub_op # NORM - SNAN
	short		tbl_fsub_op	- tbl_fsub_op #
	short		tbl_fsub_op	- tbl_fsub_op #

	short		fsub_inf_dst	- tbl_fsub_op # INF - NORM
	short		fsub_inf_dst	- tbl_fsub_op # INF - ZERO
	short		fsub_inf_2	- tbl_fsub_op # INF - INF
	short		fsub_res_qnan	- tbl_fsub_op # NORM - QNAN
	short		fsub_inf_dst	- tbl_fsub_op # INF - DENORM
	short		fsub_res_snan	- tbl_fsub_op # NORM - SNAN
	short		tbl_fsub_op	- tbl_fsub_op #
	short		tbl_fsub_op	- tbl_fsub_op #

	short		fsub_res_qnan	- tbl_fsub_op # QNAN - NORM
	short		fsub_res_qnan	- tbl_fsub_op # QNAN - ZERO
	short		fsub_res_qnan	- tbl_fsub_op # QNAN - INF
	short		fsub_res_qnan	- tbl_fsub_op # QNAN - QNAN
	short		fsub_res_qnan	- tbl_fsub_op # QNAN - DENORM
	short		fsub_res_snan	- tbl_fsub_op # QNAN - SNAN
	short		tbl_fsub_op	- tbl_fsub_op #
	short		tbl_fsub_op	- tbl_fsub_op #

	short		fsub_norm	- tbl_fsub_op # DENORM - NORM
	short		fsub_zero_src	- tbl_fsub_op # DENORM - ZERO
	short		fsub_inf_src	- tbl_fsub_op # DENORM - INF
	short		fsub_res_qnan	- tbl_fsub_op # NORM - QNAN
	short		fsub_norm	- tbl_fsub_op # DENORM - DENORM
	short		fsub_res_snan	- tbl_fsub_op # NORM - SNAN
	short		tbl_fsub_op	- tbl_fsub_op #
	short		tbl_fsub_op	- tbl_fsub_op #

	short		fsub_res_snan	- tbl_fsub_op # SNAN - NORM
	short		fsub_res_snan	- tbl_fsub_op # SNAN - ZERO
	short		fsub_res_snan	- tbl_fsub_op # SNAN - INF
	short		fsub_res_snan	- tbl_fsub_op # SNAN - QNAN
	short		fsub_res_snan	- tbl_fsub_op # SNAN - DENORM
	short		fsub_res_snan	- tbl_fsub_op # SNAN - SNAN
	short		tbl_fsub_op	- tbl_fsub_op #
	short		tbl_fsub_op	- tbl_fsub_op #

fsub_res_qnan:
	bra.l		res_qnan
fsub_res_snan:
	bra.l		res_snan

#
# both operands are ZEROes
#
fsub_zero_2:
	mov.b		SRC_EX(%a0),%d0
	mov.b		DST_EX(%a1),%d1
	eor.b		%d1,%d0
	bpl.b		fsub_zero_2_chk_rm

# the signs are opposite, so, return a ZERO w/ the sign of the dst ZERO
	tst.b		%d0			# is dst negative?
	bmi.b		fsub_zero_2_rm		# yes
	fmov.s		&0x00000000,%fp0	# no; return +ZERO
	mov.b		&z_bmask,FPSR_CC(%a6)	# set Z
	rts

#
# the ZEROes have the same signs:
# - therefore, we return +ZERO if the rounding mode is RN,RZ, or RP
# - -ZERO is returned in the case of RM.
#
fsub_zero_2_chk_rm:
	mov.b		3+L_SCR3(%a6),%d1
	andi.b		&0x30,%d1		# extract rnd mode
	cmpi.b		%d1,&rm_mode*0x10	# is rnd mode = RM?
	beq.b		fsub_zero_2_rm		# yes
	fmov.s		&0x00000000,%fp0	# no; return +ZERO
	mov.b		&z_bmask,FPSR_CC(%a6)	# set Z
	rts

fsub_zero_2_rm:
	fmov.s		&0x80000000,%fp0	# return -ZERO
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6)	# set Z/NEG
	rts

#
# one operand is a ZERO and the other is a DENORM or a NORM.
# scale the DENORM or NORM and jump to the regular fsub routine.
#
fsub_zero_dst:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	bsr.l		scale_to_zero_src	# scale the operand
	clr.w		FP_SCR1_EX(%a6)
	clr.l		FP_SCR1_HI(%a6)
	clr.l		FP_SCR1_LO(%a6)
	bra.w		fsub_zero_entry		# go execute fsub

fsub_zero_src:
	mov.w		DST_EX(%a1),FP_SCR1_EX(%a6)
	mov.l		DST_HI(%a1),FP_SCR1_HI(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)
	bsr.l		scale_to_zero_dst	# scale the operand
	clr.w		FP_SCR0_EX(%a6)
	clr.l		FP_SCR0_HI(%a6)
	clr.l		FP_SCR0_LO(%a6)
	bra.w		fsub_zero_entry		# go execute fsub

#
# both operands are INFs. an OPERR will result if the INFs have the
# same signs. else, 
#
fsub_inf_2:
	mov.b		SRC_EX(%a0),%d0		# exclusive or the signs
	mov.b		DST_EX(%a1),%d1
	eor.b		%d1,%d0
	bpl.l		res_operr		# weed out (-INF)+(+INF)

# ok, so it's not an OPERR. but we do have to remember to return
# the src INF since that's where the 881/882 gets the j-bit.

fsub_inf_src:
	fmovm.x		SRC(%a0),&0x80		# return src INF
	fneg.x		%fp0			# invert sign
	fbge.w		fsub_inf_done		# sign is now positive
	mov.b		&neg_bmask+inf_bmask,FPSR_CC(%a6) # set INF/NEG	
	rts

fsub_inf_dst:
	fmovm.x		DST(%a1),&0x80		# return dst INF
	tst.b		DST_EX(%a1)		# is INF negative?
	bpl.b		fsub_inf_done		# no
	mov.b		&neg_bmask+inf_bmask,FPSR_CC(%a6) # set INF/NEG
	rts

fsub_inf_done:
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set INF
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	fsqrt(): emulates the fsqrt instruction				#
#	fssqrt(): emulates the fssqrt instruction			#
#	fdsqrt(): emulates the fdsqrt instruction			#
#									#
# XREF ****************************************************************	#
#	scale_sqrt() - scale the source operand				#
#	unf_res() - return default underflow result			#
#	ovf_res() - return default overflow result			#
# 	res_qnan_1op() - return QNAN result				#
# 	res_snan_1op() - return SNAN result				#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	d0  rnd prec,mode						#
#									#
# OUTPUT **************************************************************	#
#	fp0 = result							#
#	fp1 = EXOP (if exception occurred)				#
#									#
# ALGORITHM ***********************************************************	#
#	Handle NANs, infinities, and zeroes as special cases. Divide	#
# norms/denorms into ext/sgl/dbl precision.				#
#	For norms/denorms, scale the exponents such that a sqrt		#
# instruction won't cause an exception. Use the regular fsqrt to	#
# compute a result. Check if the regular operands would have taken	#
# an exception. If so, return the default overflow/underflow result	#
# and return the EXOP if exceptions are enabled. Else, scale the 	#
# result operand to the proper exponent.				#
#									#
#########################################################################

	global		fssqrt
fssqrt:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl precision
	bra.b		fsqrt

	global		fdsqrt
fdsqrt:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl precision

	global		fsqrt
fsqrt:
	mov.l		%d0,L_SCR3(%a6)		# store rnd info
	clr.w		%d1
	mov.b		STAG(%a6),%d1
	bne.w		fsqrt_not_norm		# optimize on non-norm input
		
#
# SQUARE ROOT: norms and denorms ONLY!
#
fsqrt_norm:
	tst.b		SRC_EX(%a0)		# is operand negative?
	bmi.l		res_operr		# yes

	andi.b		&0xc0,%d0		# is precision extended?
	bne.b		fsqrt_not_ext		# no; go handle sgl or dbl

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsqrt.x		(%a0),%fp0		# execute square root

	fmov.l		%fpsr,%d1
	or.l		%d1,USER_FPSR(%a6)	# set N,INEX

	rts

fsqrt_denorm:
	tst.b		SRC_EX(%a0)		# is operand negative?
	bmi.l		res_operr		# yes

	andi.b		&0xc0,%d0		# is precision extended?
	bne.b		fsqrt_not_ext		# no; go handle sgl or dbl

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	bsr.l		scale_sqrt		# calculate scale factor

	bra.w		fsqrt_sd_normal

#
# operand is either single or double
#
fsqrt_not_ext:
	cmpi.b		%d0,&s_mode*0x10	# separate sgl/dbl prec
	bne.w		fsqrt_dbl

#
# operand is to be rounded to single precision
#
fsqrt_sgl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	bsr.l		scale_sqrt		# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3f81	# will move in underflow?
	beq.w		fsqrt_sd_may_unfl
	bgt.w		fsqrt_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x407f	# will move in overflow?
	beq.w		fsqrt_sd_may_ovfl	# maybe; go check
	blt.w		fsqrt_sd_ovfl		# yes; go handle overflow

#
# operand will NOT overflow or underflow when moved in to the fp reg file
#
fsqrt_sd_normal:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fsqrt.x		FP_SCR0(%a6),%fp0	# perform absolute

	fmov.l		%fpsr,%d1		# save FPSR
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fsqrt_sd_normal_exit:
	mov.l		%d2,-(%sp)		# save d2
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result
	mov.w		FP_SCR0_EX(%a6),%d1	# load sgn,exp
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	sub.l		%d0,%d1			# add scale factor
	andi.w		&0x8000,%d2		# keep old sign
	or.w		%d1,%d2			# concat old sign,new exp
	mov.w		%d2,FP_SCR0_EX(%a6)	# insert new exponent
	mov.l		(%sp)+,%d2		# restore d2
	fmovm.x		FP_SCR0(%a6),&0x80	# return result in fp0
	rts

#
# operand is to be rounded to double precision
#
fsqrt_dbl:
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	bsr.l		scale_sqrt		# calculate scale factor

	cmpi.l		%d0,&0x3fff-0x3c01	# will move in underflow?
	beq.w		fsqrt_sd_may_unfl
	bgt.b		fsqrt_sd_unfl		# yes; go handle underflow
	cmpi.l		%d0,&0x3fff-0x43ff	# will move in overflow?
	beq.w		fsqrt_sd_may_ovfl	# maybe; go check
	blt.w		fsqrt_sd_ovfl		# yes; go handle overflow
	bra.w		fsqrt_sd_normal		# no; ho handle normalized op

# we're on the line here and the distinguising characteristic is whether
# the exponent is 3fff or 3ffe. if it's 3ffe, then it's a safe number
# elsewise fall through to underflow.
fsqrt_sd_may_unfl:
	btst		&0x0,1+FP_SCR0_EX(%a6)	# is exponent 0x3fff?
	bne.w		fsqrt_sd_normal		# yes, so no underflow

#
# operand WILL underflow when moved in to the fp register file
#
fsqrt_sd_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set unfl exc bit

	fmov.l		&rz_mode*0x10,%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fsqrt.x 	FP_SCR0(%a6),%fp0	# execute square root

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

# if underflow or inexact is enabled, go calculate EXOP first.
	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0b,%d1		# is UNFL or INEX enabled?
	bne.b		fsqrt_sd_unfl_ena	# yes

fsqrt_sd_unfl_dis:
	fmovm.x		&0x80,FP_SCR0(%a6)	# store out result

	lea		FP_SCR0(%a6),%a0	# pass: result addr
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set possible 'Z' ccode
	fmovm.x		FP_SCR0(%a6),&0x80	# return default result in fp0
	rts	

#
# operand will underflow AND underflow is enabled. 
# therefore, we must return the result rounded to extended precision.
#
fsqrt_sd_unfl_ena:
	mov.l		FP_SCR0_HI(%a6),FP_SCR1_HI(%a6)
	mov.l		FP_SCR0_LO(%a6),FP_SCR1_LO(%a6)
	mov.w		FP_SCR0_EX(%a6),%d1	# load current exponent

	mov.l		%d2,-(%sp)		# save d2
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# subtract scale factor
	addi.l		&0x6000,%d1		# add new bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat new sign,new exp
	mov.w		%d1,FP_SCR1_EX(%a6)	# insert new exp
	fmovm.x		FP_SCR1(%a6),&0x40	# return EXOP in fp1
	mov.l		(%sp)+,%d2		# restore d2
	bra.b		fsqrt_sd_unfl_dis

#
# operand WILL overflow.
#
fsqrt_sd_ovfl:
	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fsqrt.x		FP_SCR0(%a6),%fp0	# perform square root

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# save FPSR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

fsqrt_sd_ovfl_tst:
	or.l		&ovfl_inx_mask,USER_FPSR(%a6) # set ovfl/aovfl/ainex

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x13,%d1		# is OVFL or INEX enabled?
	bne.b		fsqrt_sd_ovfl_ena	# yes

#
# OVFL is not enabled; therefore, we must create the default result by
# calling ovf_res().
#
fsqrt_sd_ovfl_dis:
	btst		&neg_bit,FPSR_CC(%a6)	# is result negative?
	sne		%d1			# set sign param accordingly
	mov.l		L_SCR3(%a6),%d0		# pass: prec,mode
	bsr.l		ovf_res			# calculate default result
	or.b		%d0,FPSR_CC(%a6)	# set INF,N if applicable
	fmovm.x		(%a0),&0x80		# return default result in fp0
	rts

#
# OVFL is enabled.
# the INEX2 bit has already been updated by the round to the correct precision.
# now, round to extended(and don't alter the FPSR).
#
fsqrt_sd_ovfl_ena:
	mov.l		%d2,-(%sp)		# save d2
	mov.w		FP_SCR0_EX(%a6),%d1	# fetch {sgn,exp}
	mov.l		%d1,%d2			# make a copy
	andi.l		&0x7fff,%d1		# strip sign
	andi.w		&0x8000,%d2		# keep old sign
	sub.l		%d0,%d1			# add scale factor
	subi.l		&0x6000,%d1		# subtract bias
	andi.w		&0x7fff,%d1
	or.w		%d2,%d1			# concat sign,exp
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	mov.l		(%sp)+,%d2		# restore d2
	bra.b		fsqrt_sd_ovfl_dis

#
# the move in MAY underflow. so...
#
fsqrt_sd_may_ovfl:
	btst		&0x0,1+FP_SCR0_EX(%a6)	# is exponent 0x3fff?
	bne.w		fsqrt_sd_ovfl		# yes, so overflow

	fmov.l		&0x0,%fpsr		# clear FPSR
	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fsqrt.x		FP_SCR0(%a6),%fp0	# perform absolute

	fmov.l		%fpsr,%d1		# save status
	fmov.l		&0x0,%fpcr		# clear FPCR

	or.l		%d1,USER_FPSR(%a6)	# save INEX2,N

	fmov.x		%fp0,%fp1		# make a copy of result
	fcmp.b		%fp1,&0x1		# is |result| >= 1.b?
	fbge.w		fsqrt_sd_ovfl_tst	# yes; overflow has occurred

# no, it didn't overflow; we have correct result
	bra.w		fsqrt_sd_normal_exit

##########################################################################

#
# input is not normalized; what is it?
#
fsqrt_not_norm:
	cmpi.b		%d1,&DENORM		# weed out DENORM
	beq.w		fsqrt_denorm
	cmpi.b		%d1,&ZERO		# weed out ZERO
	beq.b		fsqrt_zero
	cmpi.b		%d1,&INF		# weed out INF
	beq.b		fsqrt_inf
	cmpi.b		%d1,&SNAN		# weed out SNAN
	beq.l		res_snan_1op
	bra.l		res_qnan_1op

#
# 	fsqrt(+0) = +0
# 	fsqrt(-0) = -0
#	fsqrt(+INF) = +INF
# 	fsqrt(-INF) = OPERR
#
fsqrt_zero:
	tst.b		SRC_EX(%a0)		# is ZERO positive or negative?
	bmi.b		fsqrt_zero_m		# negative
fsqrt_zero_p:	
	fmov.s		&0x00000000,%fp0	# return +ZERO
	mov.b		&z_bmask,FPSR_CC(%a6)	# set 'Z' ccode bit
	rts
fsqrt_zero_m:
	fmov.s		&0x80000000,%fp0	# return -ZERO
	mov.b		&z_bmask+neg_bmask,FPSR_CC(%a6)	# set 'Z','N' ccode bits
	rts

fsqrt_inf:
	tst.b		SRC_EX(%a0)		# is INF positive or negative?
	bmi.l		res_operr		# negative
fsqrt_inf_p:
	fmovm.x		SRC(%a0),&0x80		# return +INF in fp0
	mov.b		&inf_bmask,FPSR_CC(%a6)	# set 'I' ccode bit
	rts

##########################################################################

#########################################################################
# XDEF ****************************************************************	#
#	addsub_scaler2(): scale inputs to fadd/fsub such that no	#
#			  OVFL/UNFL exceptions will result		#
#									#
# XREF ****************************************************************	#
#	norm() - normalize mantissa after adjusting exponent		#
#									#
# INPUT ***************************************************************	#
#	FP_SRC(a6) = fp op1(src)					#
#	FP_DST(a6) = fp op2(dst)					#
# 									#
# OUTPUT **************************************************************	#
#	FP_SRC(a6) = fp op1 scaled(src)					#
#	FP_DST(a6) = fp op2 scaled(dst)					#
#	d0         = scale amount					#
#									#
# ALGORITHM ***********************************************************	#
# 	If the DST exponent is > the SRC exponent, set the DST exponent	#
# equal to 0x3fff and scale the SRC exponent by the value that the	#
# DST exponent was scaled by. If the SRC exponent is greater or equal,	#
# do the opposite. Return this scale factor in d0.			#
#	If the two exponents differ by > the number of mantissa bits	#
# plus two, then set the smallest exponent to a very small value as a	#
# quick shortcut.							#
#									#
#########################################################################

	global		addsub_scaler2
addsub_scaler2:
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		DST_HI(%a1),FP_SCR1_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	mov.l		DST_LO(%a1),FP_SCR1_LO(%a6)
	mov.w		SRC_EX(%a0),%d0
	mov.w		DST_EX(%a1),%d1
	mov.w		%d0,FP_SCR0_EX(%a6)
	mov.w		%d1,FP_SCR1_EX(%a6)

	andi.w		&0x7fff,%d0
	andi.w		&0x7fff,%d1
	mov.w		%d0,L_SCR1(%a6)		# store src exponent
	mov.w		%d1,2+L_SCR1(%a6)	# store dst exponent

	cmp.w		%d0, %d1		# is src exp >= dst exp?
	bge.l		src_exp_ge2

# dst exp is >  src exp; scale dst to exp = 0x3fff
dst_exp_gt2:
	bsr.l		scale_to_zero_dst
	mov.l		%d0,-(%sp)		# save scale factor

	cmpi.b		STAG(%a6),&DENORM	# is dst denormalized?
	bne.b		cmpexp12

	lea		FP_SCR0(%a6),%a0
	bsr.l		norm			# normalize the denorm; result is new exp
	neg.w		%d0			# new exp = -(shft val)
	mov.w		%d0,L_SCR1(%a6)		# inset new exp

cmpexp12:
	mov.w		2+L_SCR1(%a6),%d0
	subi.w		&mantissalen+2,%d0	# subtract mantissalen+2 from larger exp

	cmp.w		%d0,L_SCR1(%a6)		# is difference >= len(mantissa)+2?
	bge.b		quick_scale12

	mov.w		L_SCR1(%a6),%d0
	add.w		0x2(%sp),%d0		# scale src exponent by scale factor
	mov.w		FP_SCR0_EX(%a6),%d1
	and.w		&0x8000,%d1
	or.w		%d1,%d0			# concat {sgn,new exp}
	mov.w		%d0,FP_SCR0_EX(%a6)	# insert new dst exponent

	mov.l		(%sp)+,%d0		# return SCALE factor
	rts

quick_scale12:
	andi.w		&0x8000,FP_SCR0_EX(%a6)	# zero src exponent
	bset		&0x0,1+FP_SCR0_EX(%a6)	# set exp = 1

	mov.l		(%sp)+,%d0		# return SCALE factor	
	rts

# src exp is >= dst exp; scale src to exp = 0x3fff
src_exp_ge2:
	bsr.l		scale_to_zero_src
	mov.l		%d0,-(%sp)		# save scale factor

	cmpi.b		DTAG(%a6),&DENORM	# is dst denormalized?
	bne.b		cmpexp22
	lea		FP_SCR1(%a6),%a0
	bsr.l		norm			# normalize the denorm; result is new exp
	neg.w		%d0			# new exp = -(shft val)
	mov.w		%d0,2+L_SCR1(%a6)	# inset new exp

cmpexp22:
	mov.w		L_SCR1(%a6),%d0
	subi.w		&mantissalen+2,%d0	# subtract mantissalen+2 from larger exp

	cmp.w		%d0,2+L_SCR1(%a6)	# is difference >= len(mantissa)+2?
	bge.b		quick_scale22

	mov.w		2+L_SCR1(%a6),%d0
	add.w		0x2(%sp),%d0		# scale dst exponent by scale factor
	mov.w		FP_SCR1_EX(%a6),%d1
	andi.w		&0x8000,%d1
	or.w		%d1,%d0			# concat {sgn,new exp}
	mov.w		%d0,FP_SCR1_EX(%a6)	# insert new dst exponent

	mov.l		(%sp)+,%d0		# return SCALE factor
	rts

quick_scale22:
	andi.w		&0x8000,FP_SCR1_EX(%a6)	# zero dst exponent
	bset		&0x0,1+FP_SCR1_EX(%a6)	# set exp = 1

	mov.l		(%sp)+,%d0		# return SCALE factor	
	rts

##########################################################################

#########################################################################
# XDEF ****************************************************************	#
#	scale_to_zero_src(): scale the exponent of extended precision	#
#			     value at FP_SCR0(a6).			#
#									#
# XREF ****************************************************************	#
#	norm() - normalize the mantissa if the operand was a DENORM	#
#									#
# INPUT ***************************************************************	#
#	FP_SCR0(a6) = extended precision operand to be scaled		#
# 									#
# OUTPUT **************************************************************	#
#	FP_SCR0(a6) = scaled extended precision operand			#
#	d0	    = scale value					#
#									#
# ALGORITHM ***********************************************************	#
# 	Set the exponent of the input operand to 0x3fff. Save the value	#
# of the difference between the original and new exponent. Then, 	#
# normalize the operand if it was a DENORM. Add this normalization	#
# value to the previous value. Return the result.			#
#									#
#########################################################################

	global		scale_to_zero_src
scale_to_zero_src:
	mov.w		FP_SCR0_EX(%a6),%d1	# extract operand's {sgn,exp}
	mov.w		%d1,%d0			# make a copy

	andi.l		&0x7fff,%d1		# extract operand's exponent

	andi.w		&0x8000,%d0		# extract operand's sgn
	or.w		&0x3fff,%d0		# insert new operand's exponent(=0)

	mov.w		%d0,FP_SCR0_EX(%a6)	# insert biased exponent

	cmpi.b		STAG(%a6),&DENORM	# is operand normalized?
	beq.b		stzs_denorm		# normalize the DENORM

stzs_norm:
	mov.l		&0x3fff,%d0
	sub.l		%d1,%d0			# scale = BIAS + (-exp)

	rts

stzs_denorm:
	lea		FP_SCR0(%a6),%a0	# pass ptr to src op
	bsr.l		norm			# normalize denorm
	neg.l		%d0			# new exponent = -(shft val)
	mov.l		%d0,%d1			# prepare for op_norm call
	bra.b		stzs_norm		# finish scaling

###

#########################################################################
# XDEF ****************************************************************	#
#	scale_sqrt(): scale the input operand exponent so a subsequent	#
#		      fsqrt operation won't take an exception.		#
#									#
# XREF ****************************************************************	#
#	norm() - normalize the mantissa if the operand was a DENORM	#
#									#
# INPUT ***************************************************************	#
#	FP_SCR0(a6) = extended precision operand to be scaled		#
# 									#
# OUTPUT **************************************************************	#
#	FP_SCR0(a6) = scaled extended precision operand			#
#	d0	    = scale value					#
#									#
# ALGORITHM ***********************************************************	#
#	If the input operand is a DENORM, normalize it.			#
# 	If the exponent of the input operand is even, set the exponent	#
# to 0x3ffe and return a scale factor of "(exp-0x3ffe)/2". If the 	#
# exponent of the input operand is off, set the exponent to ox3fff and	#
# return a scale factor of "(exp-0x3fff)/2". 				#
#									#
#########################################################################

	global		scale_sqrt
scale_sqrt:
	cmpi.b		STAG(%a6),&DENORM	# is operand normalized?
	beq.b		ss_denorm		# normalize the DENORM

	mov.w		FP_SCR0_EX(%a6),%d1	# extract operand's {sgn,exp}
	andi.l		&0x7fff,%d1		# extract operand's exponent

	andi.w		&0x8000,FP_SCR0_EX(%a6)	# extract operand's sgn

	btst		&0x0,%d1		# is exp even or odd?
	beq.b		ss_norm_even

	ori.w		&0x3fff,FP_SCR0_EX(%a6)	# insert new operand's exponent(=0)

	mov.l		&0x3fff,%d0
	sub.l		%d1,%d0			# scale = BIAS + (-exp)
	asr.l		&0x1,%d0		# divide scale factor by 2
	rts

ss_norm_even:
	ori.w		&0x3ffe,FP_SCR0_EX(%a6)	# insert new operand's exponent(=0)

	mov.l		&0x3ffe,%d0
	sub.l		%d1,%d0			# scale = BIAS + (-exp)
	asr.l		&0x1,%d0		# divide scale factor by 2
	rts

ss_denorm:
	lea		FP_SCR0(%a6),%a0	# pass ptr to src op
	bsr.l		norm			# normalize denorm

	btst		&0x0,%d0		# is exp even or odd?
	beq.b		ss_denorm_even

	ori.w		&0x3fff,FP_SCR0_EX(%a6)	# insert new operand's exponent(=0)

	add.l		&0x3fff,%d0
	asr.l		&0x1,%d0		# divide scale factor by 2
	rts

ss_denorm_even:
	ori.w		&0x3ffe,FP_SCR0_EX(%a6)	# insert new operand's exponent(=0)

	add.l		&0x3ffe,%d0
	asr.l		&0x1,%d0		# divide scale factor by 2
	rts

###

#########################################################################
# XDEF ****************************************************************	#
#	scale_to_zero_dst(): scale the exponent of extended precision	#
#			     value at FP_SCR1(a6).			#
#									#
# XREF ****************************************************************	#
#	norm() - normalize the mantissa if the operand was a DENORM	#
#									#
# INPUT ***************************************************************	#
#	FP_SCR1(a6) = extended precision operand to be scaled		#
# 									#
# OUTPUT **************************************************************	#
#	FP_SCR1(a6) = scaled extended precision operand			#
#	d0	    = scale value					#
#									#
# ALGORITHM ***********************************************************	#
# 	Set the exponent of the input operand to 0x3fff. Save the value	#
# of the difference between the original and new exponent. Then, 	#
# normalize the operand if it was a DENORM. Add this normalization	#
# value to the previous value. Return the result.			#
#									#
#########################################################################

	global		scale_to_zero_dst
scale_to_zero_dst:
	mov.w		FP_SCR1_EX(%a6),%d1	# extract operand's {sgn,exp}
	mov.w		%d1,%d0			# make a copy

	andi.l		&0x7fff,%d1		# extract operand's exponent

	andi.w		&0x8000,%d0		# extract operand's sgn
	or.w		&0x3fff,%d0		# insert new operand's exponent(=0)

	mov.w		%d0,FP_SCR1_EX(%a6)	# insert biased exponent

	cmpi.b		DTAG(%a6),&DENORM	# is operand normalized?
	beq.b		stzd_denorm		# normalize the DENORM

stzd_norm:
	mov.l		&0x3fff,%d0
	sub.l		%d1,%d0			# scale = BIAS + (-exp)
	rts

stzd_denorm:
	lea		FP_SCR1(%a6),%a0	# pass ptr to dst op
	bsr.l		norm			# normalize denorm
	neg.l		%d0			# new exponent = -(shft val)
	mov.l		%d0,%d1			# prepare for op_norm call
	bra.b		stzd_norm		# finish scaling

##########################################################################

#########################################################################
# XDEF ****************************************************************	#
#	res_qnan(): return default result w/ QNAN operand for dyadic	#
#	res_snan(): return default result w/ SNAN operand for dyadic	#
#	res_qnan_1op(): return dflt result w/ QNAN operand for monadic	#
#	res_snan_1op(): return dflt result w/ SNAN operand for monadic	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	FP_SRC(a6) = pointer to extended precision src operand		#
#	FP_DST(a6) = pointer to extended precision dst operand		#
# 									#
# OUTPUT **************************************************************	#
#	fp0 = default result						#
#									#
# ALGORITHM ***********************************************************	#
# 	If either operand (but not both operands) of an operation is a	#
# nonsignalling NAN, then that NAN is returned as the result. If both	#
# operands are nonsignalling NANs, then the destination operand 	#
# nonsignalling NAN is returned as the result.				#
# 	If either operand to an operation is a signalling NAN (SNAN),	#
# then, the SNAN bit is set in the FPSR EXC byte. If the SNAN trap	#
# enable bit is set in the FPCR, then the trap is taken and the 	#
# destination is not modified. If the SNAN trap enable bit is not set,	#
# then the SNAN is converted to a nonsignalling NAN (by setting the 	#
# SNAN bit in the operand to one), and the operation continues as 	#
# described in the preceding paragraph, for nonsignalling NANs.		#
#	Make sure the appropriate FPSR bits are set before exiting.	#
#									#
#########################################################################

	global		res_qnan
	global		res_snan
res_qnan:
res_snan:
	cmp.b		DTAG(%a6), &SNAN	# is the dst an SNAN?
	beq.b		dst_snan2
	cmp.b		DTAG(%a6), &QNAN	# is the dst a  QNAN?
	beq.b		dst_qnan2
src_nan:
	cmp.b		STAG(%a6), &QNAN
	beq.b		src_qnan2
	global		res_snan_1op
res_snan_1op:
src_snan2:
	bset		&0x6, FP_SRC_HI(%a6)	# set SNAN bit
	or.l		&nan_mask+aiop_mask+snan_mask, USER_FPSR(%a6)
	lea		FP_SRC(%a6), %a0
	bra.b		nan_comp
	global		res_qnan_1op
res_qnan_1op:
src_qnan2:
	or.l		&nan_mask, USER_FPSR(%a6)
	lea		FP_SRC(%a6), %a0
	bra.b		nan_comp
dst_snan2:
	or.l		&nan_mask+aiop_mask+snan_mask, USER_FPSR(%a6)
	bset		&0x6, FP_DST_HI(%a6)	# set SNAN bit
	lea		FP_DST(%a6), %a0
	bra.b		nan_comp
dst_qnan2:
	lea		FP_DST(%a6), %a0
	cmp.b		STAG(%a6), &SNAN
	bne		nan_done
	or.l		&aiop_mask+snan_mask, USER_FPSR(%a6)	
nan_done:
	or.l		&nan_mask, USER_FPSR(%a6)
nan_comp:
	btst		&0x7, FTEMP_EX(%a0)	# is NAN neg?
	beq.b		nan_not_neg
	or.l		&neg_mask, USER_FPSR(%a6)
nan_not_neg:
	fmovm.x		(%a0), &0x80
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	res_operr(): return default result during operand error		#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	None								#
# 									#
# OUTPUT **************************************************************	#
#	fp0 = default operand error result				#
#									#
# ALGORITHM ***********************************************************	#
#	An nonsignalling NAN is returned as the default result when	#
# an operand error occurs for the following cases:			#
#									#
# 	Multiply: (Infinity x Zero)					#
# 	Divide  : (Zero / Zero) || (Infinity / Infinity)		#
#									#
#########################################################################

	global		res_operr
res_operr:
	or.l		&nan_mask+operr_mask+aiop_mask, USER_FPSR(%a6)
	fmovm.x		nan_return(%pc), &0x80
	rts

nan_return:	
	long		0x7fff0000, 0xffffffff, 0xffffffff

#########################################################################
# fdbcc(): routine to emulate the fdbcc instruction			#
#									#
# XDEF **************************************************************** #
#	_fdbcc()							#
#									#
# XREF **************************************************************** #
#	fetch_dreg() - fetch Dn value					#
#	store_dreg_l() - store updated Dn value				#
#									#
# INPUT ***************************************************************	#
#	d0 = displacement						#
#									#
# OUTPUT ************************************************************** #
#	none								#
#									#
# ALGORITHM ***********************************************************	#
#	This routine checks which conditional predicate is specified by	#
# the stacked fdbcc instruction opcode and then branches to a routine	#
# for that predicate. The corresponding fbcc instruction is then used	#
# to see whether the condition (specified by the stacked FPSR) is true	#
# or false.								#
#	If a BSUN exception should be indicated, the BSUN and ABSUN	#
# bits are set in the stacked FPSR. If the BSUN exception is enabled,	#
# the fbsun_flg is set in the SPCOND_FLG location on the stack. If an 	#
# enabled BSUN should not be flagged and the predicate is true, then	#
# Dn is fetched and decremented by one. If Dn is not equal to -1, add	#
# the displacement value to the stacked PC so that when an "rte" is	#
# finally executed, the branch occurs.					#
#									#
#########################################################################
	global		_fdbcc
_fdbcc:
	mov.l		%d0,L_SCR1(%a6)		# save displacement

	mov.w		EXC_CMDREG(%a6),%d0	# fetch predicate

	clr.l		%d1			# clear scratch reg
	mov.b		FPSR_CC(%a6),%d1	# fetch fp ccodes
	ror.l		&0x8,%d1		# rotate to top byte
	fmov.l		%d1,%fpsr		# insert into FPSR

	mov.w		(tbl_fdbcc.b,%pc,%d0.w*2),%d1 # load table 
	jmp		(tbl_fdbcc.b,%pc,%d1.w) # jump to fdbcc routine

tbl_fdbcc:
	short		fdbcc_f		-	tbl_fdbcc	# 00
	short		fdbcc_eq	-	tbl_fdbcc	# 01
	short		fdbcc_ogt	-	tbl_fdbcc	# 02
	short		fdbcc_oge	-	tbl_fdbcc	# 03
	short		fdbcc_olt	-	tbl_fdbcc	# 04
	short		fdbcc_ole	-	tbl_fdbcc	# 05
	short		fdbcc_ogl	-	tbl_fdbcc	# 06
	short		fdbcc_or	-	tbl_fdbcc	# 07
	short		fdbcc_un	-	tbl_fdbcc	# 08
	short		fdbcc_ueq	-	tbl_fdbcc	# 09
	short		fdbcc_ugt	-	tbl_fdbcc	# 10
	short		fdbcc_uge	-	tbl_fdbcc	# 11
	short		fdbcc_ult	-	tbl_fdbcc	# 12
	short		fdbcc_ule	-	tbl_fdbcc	# 13
	short		fdbcc_neq	-	tbl_fdbcc	# 14
	short		fdbcc_t		-	tbl_fdbcc	# 15
	short		fdbcc_sf	-	tbl_fdbcc	# 16
	short		fdbcc_seq	-	tbl_fdbcc	# 17
	short		fdbcc_gt	-	tbl_fdbcc	# 18
	short		fdbcc_ge	-	tbl_fdbcc	# 19
	short		fdbcc_lt	-	tbl_fdbcc	# 20
	short		fdbcc_le	-	tbl_fdbcc	# 21
	short		fdbcc_gl	-	tbl_fdbcc	# 22
	short		fdbcc_gle	-	tbl_fdbcc	# 23
	short		fdbcc_ngle	-	tbl_fdbcc	# 24
	short		fdbcc_ngl	-	tbl_fdbcc	# 25
	short		fdbcc_nle	-	tbl_fdbcc	# 26
	short		fdbcc_nlt	-	tbl_fdbcc	# 27
	short		fdbcc_nge	-	tbl_fdbcc	# 28
	short		fdbcc_ngt	-	tbl_fdbcc	# 29
	short		fdbcc_sneq	-	tbl_fdbcc	# 30
	short		fdbcc_st	-	tbl_fdbcc	# 31

#########################################################################
#									#
# IEEE Nonaware tests							#
#									#
# For the IEEE nonaware tests, only the false branch changes the 	#
# counter. However, the true branch may set bsun so we check to see	#
# if the NAN bit is set, in which case BSUN and AIOP will be set.	#
#									#
# The cases EQ and NE are shared by the Aware and Nonaware groups	#
# and are incapable of setting the BSUN exception bit.			#
#									#
# Typically, only one of the two possible branch directions could	#
# have the NAN bit set.							#
# (This is assuming the mutual exclusiveness of FPSR cc bit groupings	#
#  is preserved.)							#
#									#
#########################################################################

#
# equal:
#
#	Z
#
fdbcc_eq:
	fbeq.w		fdbcc_eq_yes		# equal?
fdbcc_eq_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_eq_yes:
	rts

#
# not equal:
#	_
#	Z
#
fdbcc_neq:
	fbneq.w		fdbcc_neq_yes		# not equal?
fdbcc_neq_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_neq_yes:
	rts

#
# greater than:
#	_______
#	NANvZvN
#
fdbcc_gt:
	fbgt.w		fdbcc_gt_yes		# greater than?
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fdbcc_false		# no;go handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_gt_yes:
	rts					# do nothing

#
# not greater than:
#
#	NANvZvN	
#
fdbcc_ngt:
	fbngt.w		fdbcc_ngt_yes		# not greater than?
fdbcc_ngt_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ngt_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		fdbcc_ngt_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
fdbcc_ngt_done:
	rts					# no; do nothing

#
# greater than or equal:
#	   _____
#	Zv(NANvN)
#
fdbcc_ge:
	fbge.w		fdbcc_ge_yes		# greater than or equal?
fdbcc_ge_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fdbcc_false		# no;go handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ge_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		fdbcc_ge_yes_done	# no;go do nothing
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
fdbcc_ge_yes_done:
	rts					# do nothing

#
# not (greater than or equal):
#	       _
#	NANv(N^Z)
#
fdbcc_nge:
	fbnge.w		fdbcc_nge_yes		# not (greater than or equal)?
fdbcc_nge_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_nge_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		fdbcc_nge_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
fdbcc_nge_done:
	rts					# no; do nothing

#
# less than:
#	   _____
#	N^(NANvZ)
#
fdbcc_lt:
	fblt.w		fdbcc_lt_yes		# less than?
fdbcc_lt_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fdbcc_false		# no; go handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_lt_yes:
	rts					# do nothing

#
# not less than:
#	       _
#	NANv(ZvN)
#
fdbcc_nlt:
	fbnlt.w		fdbcc_nlt_yes		# not less than?
fdbcc_nlt_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_nlt_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		fdbcc_nlt_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
fdbcc_nlt_done:
	rts					# no; do nothing

#
# less than or equal:
#	     ___
#	Zv(N^NAN)
#
fdbcc_le:
	fble.w		fdbcc_le_yes		# less than or equal?
fdbcc_le_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fdbcc_false		# no; go handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_le_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		fdbcc_le_yes_done	# no; go do nothing
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception	
fdbcc_le_yes_done:
	rts					# do nothing

#
# not (less than or equal):
#	     ___
#	NANv(NvZ)
#
fdbcc_nle:
	fbnle.w		fdbcc_nle_yes		# not (less than or equal)?
fdbcc_nle_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_nle_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fdbcc_nle_done		# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
fdbcc_nle_done:
	rts					# no; do nothing

#
# greater or less than:
#	_____
#	NANvZ
#
fdbcc_gl:
	fbgl.w		fdbcc_gl_yes		# greater or less than?
fdbcc_gl_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fdbcc_false		# no; handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_gl_yes:
	rts					# do nothing

#
# not (greater or less than):
#
#	NANvZ
#
fdbcc_ngl:
	fbngl.w		fdbcc_ngl_yes		# not (greater or less than)?
fdbcc_ngl_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ngl_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		fdbcc_ngl_done		# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
fdbcc_ngl_done:
	rts					# no; do nothing

#
# greater, less, or equal:
#	___
#	NAN
#
fdbcc_gle:
	fbgle.w		fdbcc_gle_yes		# greater, less, or equal?
fdbcc_gle_no:
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_gle_yes:
	rts					# do nothing

#
# not (greater, less, or equal):
#
#	NAN
#
fdbcc_ngle:
	fbngle.w	fdbcc_ngle_yes		# not (greater, less, or equal)?
fdbcc_ngle_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ngle_yes:
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
	rts					# no; do nothing

#########################################################################
#									#
# Miscellaneous tests							#
#									#
# For the IEEE miscellaneous tests, all but fdbf and fdbt can set bsun. #
#									#
#########################################################################

#
# false:
#
#	False
#
fdbcc_f:					# no bsun possible
	bra.w		fdbcc_false		# go handle counter

#
# true:
#
#	True
#
fdbcc_t:					# no bsun possible
	rts					# do nothing

#
# signalling false:
#
#	False
#
fdbcc_sf:
	btst		&nan_bit, FPSR_CC(%a6) 	# is NAN set?
	beq.w		fdbcc_false		# no;go handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
	bra.w		fdbcc_false		# go handle counter

#
# signalling true:
#
#	True
#
fdbcc_st:
	btst		&nan_bit, FPSR_CC(%a6) 	# is NAN set?
	beq.b		fdbcc_st_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
fdbcc_st_done:
	rts

#
# signalling equal:
#
#	Z
#
fdbcc_seq:
	fbseq.w		fdbcc_seq_yes		# signalling equal?
fdbcc_seq_no:
	btst		&nan_bit, FPSR_CC(%a6) 	# is NAN set?
	beq.w		fdbcc_false		# no;go handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
	bra.w		fdbcc_false		# go handle counter
fdbcc_seq_yes:
	btst		&nan_bit, FPSR_CC(%a6) 	# is NAN set?
	beq.b		fdbcc_seq_yes_done	# no;go do nothing
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
fdbcc_seq_yes_done:
	rts					# yes; do nothing

#
# signalling not equal:
#	_
#	Z
#
fdbcc_sneq:
	fbsneq.w	fdbcc_sneq_yes		# signalling not equal?
fdbcc_sneq_no:
	btst		&nan_bit, FPSR_CC(%a6) 	# is NAN set?
	beq.w		fdbcc_false		# no;go handle counter
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
	bra.w		fdbcc_false		# go handle counter
fdbcc_sneq_yes:
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		fdbcc_sneq_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # is BSUN enabled?
	bne.w		fdbcc_bsun		# yes; we have an exception
fdbcc_sneq_done:
	rts

#########################################################################
#									#
# IEEE Aware tests							#
#									#
# For the IEEE aware tests, action is only taken if the result is false.#
# Therefore, the opposite branch type is used to jump to the decrement	#
# routine. 								#
# The BSUN exception will not be set for any of these tests.		#
#									#
#########################################################################

#
# ordered greater than:
#	_______
#	NANvZvN
#
fdbcc_ogt:
	fbogt.w		fdbcc_ogt_yes		# ordered greater than?
fdbcc_ogt_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ogt_yes:
	rts					# yes; do nothing

#
# unordered or less or equal:
#	_______
#	NANvZvN
#
fdbcc_ule:
	fbule.w		fdbcc_ule_yes		# unordered or less or equal?
fdbcc_ule_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ule_yes:
	rts					# yes; do nothing

#
# ordered greater than or equal:
#	   _____
#	Zv(NANvN)
#
fdbcc_oge:
	fboge.w		fdbcc_oge_yes		# ordered greater than or equal?
fdbcc_oge_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_oge_yes:
	rts					# yes; do nothing

#
# unordered or less than:
#	       _
#	NANv(N^Z)
#
fdbcc_ult:
	fbult.w		fdbcc_ult_yes		# unordered or less than?
fdbcc_ult_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ult_yes:
	rts					# yes; do nothing

#
# ordered less than:
#	   _____
#	N^(NANvZ)
#
fdbcc_olt:
	fbolt.w		fdbcc_olt_yes		# ordered less than?
fdbcc_olt_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_olt_yes:
	rts					# yes; do nothing

#
# unordered or greater or equal:
#
#	NANvZvN
#
fdbcc_uge:
	fbuge.w		fdbcc_uge_yes		# unordered or greater than?
fdbcc_uge_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_uge_yes:
	rts					# yes; do nothing

#
# ordered less than or equal:
#	     ___
#	Zv(N^NAN)
#
fdbcc_ole:
	fbole.w		fdbcc_ole_yes		# ordered greater or less than?
fdbcc_ole_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ole_yes:
	rts					# yes; do nothing

#
# unordered or greater than:
#	     ___
#	NANv(NvZ)
#
fdbcc_ugt:
	fbugt.w		fdbcc_ugt_yes		# unordered or greater than?
fdbcc_ugt_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ugt_yes:
	rts					# yes; do nothing

#
# ordered greater or less than:
#	_____
#	NANvZ
#
fdbcc_ogl:
	fbogl.w		fdbcc_ogl_yes		# ordered greater or less than?
fdbcc_ogl_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ogl_yes:
	rts					# yes; do nothing

#
# unordered or equal:
#
#	NANvZ
#
fdbcc_ueq:
	fbueq.w		fdbcc_ueq_yes		# unordered or equal?
fdbcc_ueq_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_ueq_yes:
	rts					# yes; do nothing

#
# ordered:
#	___
#	NAN
#
fdbcc_or:
	fbor.w		fdbcc_or_yes		# ordered?
fdbcc_or_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_or_yes:
	rts					# yes; do nothing

#
# unordered:
#
#	NAN
#
fdbcc_un:
	fbun.w		fdbcc_un_yes		# unordered?
fdbcc_un_no:
	bra.w		fdbcc_false		# no; go handle counter
fdbcc_un_yes:
	rts					# yes; do nothing

#######################################################################

#
# the bsun exception bit was not set.
#
# (1) subtract 1 from the count register
# (2) if (cr == -1) then
#	pc = pc of next instruction
#     else
#	pc += sign_ext(16-bit displacement)
#
fdbcc_false:
	mov.b		1+EXC_OPWORD(%a6), %d1	# fetch lo opword 
	andi.w		&0x7, %d1		# extract count register

	bsr.l		fetch_dreg		# fetch count value
# make sure that d0 isn't corrupted between calls...

	subq.w		&0x1, %d0		# Dn - 1 -> Dn

	bsr.l		store_dreg_l		# store new count value

	cmpi.w		%d0, &-0x1		# is (Dn == -1)?
	bne.b		fdbcc_false_cont	# no; 
	rts

fdbcc_false_cont:
	mov.l		L_SCR1(%a6),%d0		# fetch displacement
	add.l		USER_FPIAR(%a6),%d0	# add instruction PC
	addq.l		&0x4,%d0		# add instruction length
	mov.l		%d0,EXC_PC(%a6)		# set new PC
	rts

# the emulation routine set bsun and BSUN was enabled. have to
# fix stack and jump to the bsun handler.
# let the caller of this routine shift the stack frame up to
# eliminate the effective address field.
fdbcc_bsun:
	mov.b		&fbsun_flg,SPCOND_FLG(%a6)
	rts

#########################################################################
# ftrapcc(): routine to emulate the ftrapcc instruction			#
#									#
# XDEF ****************************************************************	#
#	_ftrapcc()							#
#									#
# XREF ****************************************************************	#
#	none								#
#									#
# INPUT *************************************************************** #
#	none								#
#									#
# OUTPUT ************************************************************** #
#	none								#
#									#
# ALGORITHM *********************************************************** #
#	This routine checks which conditional predicate is specified by	#
# the stacked ftrapcc instruction opcode and then branches to a routine	#
# for that predicate. The corresponding fbcc instruction is then used	#
# to see whether the condition (specified by the stacked FPSR) is true	#
# or false.								#
#	If a BSUN exception should be indicated, the BSUN and ABSUN	#
# bits are set in the stacked FPSR. If the BSUN exception is enabled,	#
# the fbsun_flg is set in the SPCOND_FLG location on the stack. If an 	#
# enabled BSUN should not be flagged and the predicate is true, then	#
# the ftrapcc_flg is set in the SPCOND_FLG location. These special	#
# flags indicate to the calling routine to emulate the exceptional	#
# condition.								#
#									#
#########################################################################

	global		_ftrapcc
_ftrapcc:
	mov.w		EXC_CMDREG(%a6),%d0	# fetch predicate

	clr.l		%d1			# clear scratch reg
	mov.b		FPSR_CC(%a6),%d1	# fetch fp ccodes
	ror.l		&0x8,%d1		# rotate to top byte
	fmov.l		%d1,%fpsr		# insert into FPSR

	mov.w		(tbl_ftrapcc.b,%pc,%d0.w*2), %d1 # load table 
	jmp		(tbl_ftrapcc.b,%pc,%d1.w) # jump to ftrapcc routine

tbl_ftrapcc:
	short		ftrapcc_f	-	tbl_ftrapcc	# 00
	short		ftrapcc_eq	-	tbl_ftrapcc	# 01
	short		ftrapcc_ogt	-	tbl_ftrapcc	# 02
	short		ftrapcc_oge	-	tbl_ftrapcc	# 03
	short		ftrapcc_olt	-	tbl_ftrapcc	# 04
	short		ftrapcc_ole	-	tbl_ftrapcc	# 05
	short		ftrapcc_ogl	-	tbl_ftrapcc	# 06
	short		ftrapcc_or	-	tbl_ftrapcc	# 07
	short		ftrapcc_un	-	tbl_ftrapcc	# 08
	short		ftrapcc_ueq	-	tbl_ftrapcc	# 09
	short		ftrapcc_ugt	-	tbl_ftrapcc	# 10
	short		ftrapcc_uge	-	tbl_ftrapcc	# 11
	short		ftrapcc_ult	-	tbl_ftrapcc	# 12
	short		ftrapcc_ule	-	tbl_ftrapcc	# 13
	short		ftrapcc_neq	-	tbl_ftrapcc	# 14
	short		ftrapcc_t	-	tbl_ftrapcc	# 15
	short		ftrapcc_sf	-	tbl_ftrapcc	# 16
	short		ftrapcc_seq	-	tbl_ftrapcc	# 17
	short		ftrapcc_gt	-	tbl_ftrapcc	# 18
	short		ftrapcc_ge	-	tbl_ftrapcc	# 19
	short		ftrapcc_lt	-	tbl_ftrapcc	# 20
	short		ftrapcc_le	-	tbl_ftrapcc	# 21
	short		ftrapcc_gl	-	tbl_ftrapcc	# 22
	short		ftrapcc_gle	-	tbl_ftrapcc	# 23
	short		ftrapcc_ngle	-	tbl_ftrapcc	# 24
	short		ftrapcc_ngl	-	tbl_ftrapcc	# 25
	short		ftrapcc_nle	-	tbl_ftrapcc	# 26
	short		ftrapcc_nlt	-	tbl_ftrapcc	# 27
	short		ftrapcc_nge	-	tbl_ftrapcc	# 28
	short		ftrapcc_ngt	-	tbl_ftrapcc	# 29
	short		ftrapcc_sneq	-	tbl_ftrapcc	# 30
	short		ftrapcc_st	-	tbl_ftrapcc	# 31

#########################################################################
#									#
# IEEE Nonaware tests							#
#									#
# For the IEEE nonaware tests, we set the result based on the		#
# floating point condition codes. In addition, we check to see		#
# if the NAN bit is set, in which case BSUN and AIOP will be set.	#
#									#
# The cases EQ and NE are shared by the Aware and Nonaware groups	#
# and are incapable of setting the BSUN exception bit.			#
#									#
# Typically, only one of the two possible branch directions could	#
# have the NAN bit set.							#
#									#
#########################################################################

#
# equal:
#
#	Z
#
ftrapcc_eq:
	fbeq.w		ftrapcc_trap		# equal?
ftrapcc_eq_no:
	rts					# do nothing

#
# not equal:
#	_
#	Z
#
ftrapcc_neq:
	fbneq.w		ftrapcc_trap		# not equal?
ftrapcc_neq_no:
	rts					# do nothing

#
# greater than:
#	_______
#	NANvZvN
#
ftrapcc_gt:
	fbgt.w		ftrapcc_trap		# greater than?
ftrapcc_gt_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		ftrapcc_gt_done		# no
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_gt_done:
	rts					# no; do nothing

#
# not greater than:
#
#	NANvZvN	
#
ftrapcc_ngt:
	fbngt.w		ftrapcc_ngt_yes		# not greater than?
ftrapcc_ngt_no:
	rts					# do nothing
ftrapcc_ngt_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# greater than or equal:
#	   _____
#	Zv(NANvN)
#
ftrapcc_ge:
	fbge.w		ftrapcc_ge_yes		# greater than or equal?
ftrapcc_ge_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		ftrapcc_ge_done		# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_ge_done:
	rts					# no; do nothing
ftrapcc_ge_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# not (greater than or equal):
#	       _
#	NANv(N^Z)
#
ftrapcc_nge:
	fbnge.w		ftrapcc_nge_yes		# not (greater than or equal)?
ftrapcc_nge_no:
	rts					# do nothing
ftrapcc_nge_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# less than:
#	   _____
#	N^(NANvZ)
#
ftrapcc_lt:
	fblt.w		ftrapcc_trap		# less than?
ftrapcc_lt_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		ftrapcc_lt_done		# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_lt_done:
	rts					# no; do nothing

#
# not less than:
#	       _
#	NANv(ZvN)
#
ftrapcc_nlt:
	fbnlt.w		ftrapcc_nlt_yes		# not less than?
ftrapcc_nlt_no:
	rts					# do nothing
ftrapcc_nlt_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# less than or equal:
#	     ___
#	Zv(N^NAN)
#
ftrapcc_le:
	fble.w		ftrapcc_le_yes		# less than or equal?
ftrapcc_le_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		ftrapcc_le_done		# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_le_done:
	rts					# no; do nothing
ftrapcc_le_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# not (less than or equal):
#	     ___
#	NANv(NvZ)
#
ftrapcc_nle:
	fbnle.w		ftrapcc_nle_yes		# not (less than or equal)?
ftrapcc_nle_no:
	rts					# do nothing
ftrapcc_nle_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# greater or less than:
#	_____
#	NANvZ
#
ftrapcc_gl:
	fbgl.w		ftrapcc_trap		# greater or less than?
ftrapcc_gl_no:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.b		ftrapcc_gl_done		# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_gl_done:
	rts					# no; do nothing

#
# not (greater or less than):
#
#	NANvZ
#
ftrapcc_ngl:
	fbngl.w		ftrapcc_ngl_yes		# not (greater or less than)?
ftrapcc_ngl_no:
	rts					# do nothing
ftrapcc_ngl_yes:
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# greater, less, or equal:
#	___
#	NAN
#
ftrapcc_gle:
	fbgle.w		ftrapcc_trap		# greater, less, or equal?
ftrapcc_gle_no:
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	rts					# no; do nothing

#
# not (greater, less, or equal):
#
#	NAN
#
ftrapcc_ngle:
	fbngle.w	ftrapcc_ngle_yes	# not (greater, less, or equal)?
ftrapcc_ngle_no:
	rts					# do nothing
ftrapcc_ngle_yes:
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#########################################################################
#									#
# Miscellaneous tests							#
#									#
# For the IEEE aware tests, we only have to set the result based on the	#
# floating point condition codes. The BSUN exception will not be	#
# set for any of these tests.						#
#									#
#########################################################################

#
# false:
#
#	False
#
ftrapcc_f:
	rts					# do nothing

#
# true:
#
#	True
#
ftrapcc_t:
	bra.w		ftrapcc_trap		# go take trap

#
# signalling false:
#
#	False
#
ftrapcc_sf:
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.b		ftrapcc_sf_done		# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_sf_done:
	rts					# no; do nothing

#
# signalling true:
#
#	True
#
ftrapcc_st:
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# signalling equal:
#
#	Z
#
ftrapcc_seq:
	fbseq.w		ftrapcc_seq_yes		# signalling equal?
ftrapcc_seq_no:
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		ftrapcc_seq_done	# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_seq_done:
	rts					# no; do nothing
ftrapcc_seq_yes:
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#
# signalling not equal:
#	_
#	Z
#
ftrapcc_sneq:
	fbsneq.w	ftrapcc_sneq_yes	# signalling equal?
ftrapcc_sneq_no:
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		ftrapcc_sneq_no_done	# no; go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
ftrapcc_sneq_no_done:
	rts					# do nothing
ftrapcc_sneq_yes:
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		ftrapcc_trap		# no; go take trap
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	btst		&bsun_bit, FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		ftrapcc_bsun		# yes
	bra.w		ftrapcc_trap		# no; go take trap

#########################################################################
#									#
# IEEE Aware tests							#
#									#
# For the IEEE aware tests, we only have to set the result based on the	#
# floating point condition codes. The BSUN exception will not be	#
# set for any of these tests.						#
#									#
#########################################################################

#
# ordered greater than:
#	_______
#	NANvZvN
#
ftrapcc_ogt:
	fbogt.w		ftrapcc_trap		# ordered greater than?
ftrapcc_ogt_no:
	rts					# do nothing

#
# unordered or less or equal:
#	_______
#	NANvZvN
#
ftrapcc_ule:
	fbule.w		ftrapcc_trap		# unordered or less or equal?
ftrapcc_ule_no:
	rts					# do nothing

#
# ordered greater than or equal:
#	   _____
#	Zv(NANvN)
#
ftrapcc_oge:
	fboge.w		ftrapcc_trap		# ordered greater than or equal?
ftrapcc_oge_no:
	rts					# do nothing

#
# unordered or less than:
#	       _
#	NANv(N^Z)
#
ftrapcc_ult:
	fbult.w		ftrapcc_trap		# unordered or less than?
ftrapcc_ult_no:
	rts					# do nothing

#
# ordered less than:
#	   _____
#	N^(NANvZ)
#
ftrapcc_olt:
	fbolt.w		ftrapcc_trap		# ordered less than?
ftrapcc_olt_no:
	rts					# do nothing

#
# unordered or greater or equal:
#
#	NANvZvN
#
ftrapcc_uge:
	fbuge.w		ftrapcc_trap		# unordered or greater than?
ftrapcc_uge_no:
	rts					# do nothing

#
# ordered less than or equal:
#	     ___
#	Zv(N^NAN)
#
ftrapcc_ole:
	fbole.w		ftrapcc_trap		# ordered greater or less than?
ftrapcc_ole_no:
	rts					# do nothing

#
# unordered or greater than:
#	     ___
#	NANv(NvZ)
#
ftrapcc_ugt:
	fbugt.w		ftrapcc_trap		# unordered or greater than?
ftrapcc_ugt_no:
	rts					# do nothing

#
# ordered greater or less than:
#	_____
#	NANvZ
#
ftrapcc_ogl:
	fbogl.w		ftrapcc_trap		# ordered greater or less than?
ftrapcc_ogl_no:
	rts					# do nothing

#
# unordered or equal:
#
#	NANvZ
#
ftrapcc_ueq:
	fbueq.w		ftrapcc_trap		# unordered or equal?
ftrapcc_ueq_no:
	rts					# do nothing

#
# ordered:
#	___
#	NAN
#
ftrapcc_or:
	fbor.w		ftrapcc_trap		# ordered?
ftrapcc_or_no:
	rts					# do nothing

#
# unordered:
#
#	NAN
#
ftrapcc_un:
	fbun.w		ftrapcc_trap		# unordered?
ftrapcc_un_no:
	rts					# do nothing

#######################################################################

# the bsun exception bit was not set.
# we will need to jump to the ftrapcc vector. the stack frame
# is the same size as that of the fp unimp instruction. the
# only difference is that the <ea> field should hold the PC
# of the ftrapcc instruction and the vector offset field
# should denote the ftrapcc trap.
ftrapcc_trap:
	mov.b		&ftrapcc_flg,SPCOND_FLG(%a6)
	rts

# the emulation routine set bsun and BSUN was enabled. have to
# fix stack and jump to the bsun handler.
# let the caller of this routine shift the stack frame up to
# eliminate the effective address field.
ftrapcc_bsun:
	mov.b		&fbsun_flg,SPCOND_FLG(%a6)
	rts

#########################################################################
# fscc(): routine to emulate the fscc instruction			#
#									#
# XDEF **************************************************************** #
#	_fscc()								#
#									#
# XREF **************************************************************** #
#	store_dreg_b() - store result to data register file		#
#	dec_areg() - decrement an areg for -(an) mode			#
#	inc_areg() - increment an areg for (an)+ mode			#
#	_dmem_write_byte() - store result to memory			#
#									#
# INPUT ***************************************************************	#
#	none								#
#									#
# OUTPUT ************************************************************** #
#	none								#
#									#
# ALGORITHM ***********************************************************	#
#	This routine checks which conditional predicate is specified by	#
# the stacked fscc instruction opcode and then branches to a routine	#
# for that predicate. The corresponding fbcc instruction is then used	#
# to see whether the condition (specified by the stacked FPSR) is true	#
# or false.								#
#	If a BSUN exception should be indicated, the BSUN and ABSUN	#
# bits are set in the stacked FPSR. If the BSUN exception is enabled,	#
# the fbsun_flg is set in the SPCOND_FLG location on the stack. If an 	#
# enabled BSUN should not be flagged and the predicate is true, then	#
# the result is stored to the data register file or memory		#
#									#
#########################################################################

	global		_fscc
_fscc:
	mov.w		EXC_CMDREG(%a6),%d0	# fetch predicate

	clr.l		%d1			# clear scratch reg
	mov.b		FPSR_CC(%a6),%d1	# fetch fp ccodes
	ror.l		&0x8,%d1		# rotate to top byte
	fmov.l		%d1,%fpsr		# insert into FPSR

	mov.w		(tbl_fscc.b,%pc,%d0.w*2),%d1 # load table 
	jmp		(tbl_fscc.b,%pc,%d1.w) 	# jump to fscc routine

tbl_fscc:
	short		fscc_f		-	tbl_fscc	# 00
	short		fscc_eq		-	tbl_fscc	# 01
	short		fscc_ogt	-	tbl_fscc	# 02
	short		fscc_oge	-	tbl_fscc	# 03
	short		fscc_olt	-	tbl_fscc	# 04
	short		fscc_ole	-	tbl_fscc	# 05
	short		fscc_ogl	-	tbl_fscc	# 06
	short		fscc_or		-	tbl_fscc	# 07
	short		fscc_un		-	tbl_fscc	# 08
	short		fscc_ueq	-	tbl_fscc	# 09
	short		fscc_ugt	-	tbl_fscc	# 10
	short		fscc_uge	-	tbl_fscc	# 11
	short		fscc_ult	-	tbl_fscc	# 12
	short		fscc_ule	-	tbl_fscc	# 13
	short		fscc_neq	-	tbl_fscc	# 14
	short		fscc_t		-	tbl_fscc	# 15
	short		fscc_sf		-	tbl_fscc	# 16
	short		fscc_seq	-	tbl_fscc	# 17
	short		fscc_gt		-	tbl_fscc	# 18
	short		fscc_ge		-	tbl_fscc	# 19
	short		fscc_lt		-	tbl_fscc	# 20
	short		fscc_le		-	tbl_fscc	# 21
	short		fscc_gl		-	tbl_fscc	# 22
	short		fscc_gle	-	tbl_fscc	# 23
	short		fscc_ngle	-	tbl_fscc	# 24
	short		fscc_ngl	-	tbl_fscc	# 25
	short		fscc_nle	-	tbl_fscc	# 26
	short		fscc_nlt	-	tbl_fscc	# 27
	short		fscc_nge	-	tbl_fscc	# 28
	short		fscc_ngt	-	tbl_fscc	# 29
	short		fscc_sneq	-	tbl_fscc	# 30
	short		fscc_st		-	tbl_fscc	# 31

#########################################################################
#									#
# IEEE Nonaware tests							#
#									#
# For the IEEE nonaware tests, we set the result based on the		#
# floating point condition codes. In addition, we check to see		#
# if the NAN bit is set, in which case BSUN and AIOP will be set.	#
#									#
# The cases EQ and NE are shared by the Aware and Nonaware groups	#
# and are incapable of setting the BSUN exception bit.			#
#									#
# Typically, only one of the two possible branch directions could	#
# have the NAN bit set.							#
#									#
#########################################################################

#
# equal:
#
#	Z
#
fscc_eq:
	fbeq.w		fscc_eq_yes		# equal?
fscc_eq_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_eq_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# not equal:
#	_
#	Z
#
fscc_neq:
	fbneq.w		fscc_neq_yes		# not equal?
fscc_neq_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_neq_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# greater than:
#	_______
#	NANvZvN
#
fscc_gt:
	fbgt.w		fscc_gt_yes		# greater than?
fscc_gt_no:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_gt_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# not greater than:
#
#	NANvZvN	
#
fscc_ngt:
	fbngt.w		fscc_ngt_yes		# not greater than?
fscc_ngt_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ngt_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# greater than or equal:
#	   _____
#	Zv(NANvN)
#
fscc_ge:
	fbge.w		fscc_ge_yes		# greater than or equal?
fscc_ge_no:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_ge_yes:
	st		%d0			# set true	
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# not (greater than or equal):
#	       _
#	NANv(N^Z)
#
fscc_nge:
	fbnge.w		fscc_nge_yes		# not (greater than or equal)?
fscc_nge_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_nge_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# less than:
#	   _____
#	N^(NANvZ)
#
fscc_lt:
	fblt.w		fscc_lt_yes		# less than?
fscc_lt_no:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_lt_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# not less than:
#	       _
#	NANv(ZvN)
#
fscc_nlt:
	fbnlt.w		fscc_nlt_yes		# not less than?
fscc_nlt_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_nlt_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# less than or equal:
#	     ___
#	Zv(N^NAN)
#
fscc_le:
	fble.w		fscc_le_yes		# less than or equal?
fscc_le_no:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_le_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# not (less than or equal):
#	     ___
#	NANv(NvZ)
#
fscc_nle:
	fbnle.w		fscc_nle_yes		# not (less than or equal)?
fscc_nle_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_nle_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# greater or less than:
#	_____
#	NANvZ
#
fscc_gl:
	fbgl.w		fscc_gl_yes		# greater or less than?
fscc_gl_no:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_gl_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# not (greater or less than):
#
#	NANvZ
#
fscc_ngl:
	fbngl.w		fscc_ngl_yes		# not (greater or less than)?
fscc_ngl_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ngl_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6)	# is NAN set in cc?
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# greater, less, or equal:
#	___
#	NAN
#
fscc_gle:
	fbgle.w		fscc_gle_yes		# greater, less, or equal?
fscc_gle_no:
	clr.b		%d0			# set false
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_gle_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# not (greater, less, or equal):
#
#	NAN
#
fscc_ngle:
	fbngle.w		fscc_ngle_yes	# not (greater, less, or equal)?
fscc_ngle_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ngle_yes:
	st		%d0			# set true
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#########################################################################
#									#
# Miscellaneous tests							#
#									#
# For the IEEE aware tests, we only have to set the result based on the	#
# floating point condition codes. The BSUN exception will not be	#
# set for any of these tests.						#
#									#
#########################################################################

#
# false:
#
#	False
#
fscc_f:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish

#
# true:
#
#	True
#
fscc_t:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# signalling false:
#
#	False
#
fscc_sf:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# signalling true:
#
#	True
#
fscc_st:
	st		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# signalling equal:
#
#	Z
#
fscc_seq:
	fbseq.w		fscc_seq_yes		# signalling equal?
fscc_seq_no:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_seq_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#
# signalling not equal:
#	_
#	Z
#
fscc_sneq:
	fbsneq.w	fscc_sneq_yes		# signalling equal?
fscc_sneq_no:
	clr.b		%d0			# set false
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish
fscc_sneq_yes:
	st		%d0			# set true
	btst		&nan_bit, FPSR_CC(%a6) 	# set BSUN exc bit
	beq.w		fscc_done		# no;go finish
	ori.l		&bsun_mask+aiop_mask, USER_FPSR(%a6) # set BSUN exc bit
	bra.w		fscc_chk_bsun		# go finish

#########################################################################
#									#
# IEEE Aware tests							#
#									#
# For the IEEE aware tests, we only have to set the result based on the	#
# floating point condition codes. The BSUN exception will not be	#
# set for any of these tests.						#
#									#
#########################################################################

#
# ordered greater than:
#	_______
#	NANvZvN
#
fscc_ogt:
	fbogt.w		fscc_ogt_yes		# ordered greater than?
fscc_ogt_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ogt_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# unordered or less or equal:
#	_______
#	NANvZvN
#
fscc_ule:
	fbule.w		fscc_ule_yes		# unordered or less or equal?
fscc_ule_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ule_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# ordered greater than or equal:
#	   _____
#	Zv(NANvN)
#
fscc_oge:
	fboge.w		fscc_oge_yes		# ordered greater than or equal?
fscc_oge_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_oge_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# unordered or less than:
#	       _
#	NANv(N^Z)
#
fscc_ult:
	fbult.w		fscc_ult_yes		# unordered or less than?
fscc_ult_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ult_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# ordered less than:
#	   _____
#	N^(NANvZ)
#
fscc_olt:
	fbolt.w		fscc_olt_yes		# ordered less than?
fscc_olt_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_olt_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# unordered or greater or equal:
#
#	NANvZvN
#
fscc_uge:
	fbuge.w		fscc_uge_yes		# unordered or greater than?
fscc_uge_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_uge_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# ordered less than or equal:
#	     ___
#	Zv(N^NAN)
#
fscc_ole:
	fbole.w		fscc_ole_yes		# ordered greater or less than?
fscc_ole_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ole_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# unordered or greater than:
#	     ___
#	NANv(NvZ)
#
fscc_ugt:
	fbugt.w		fscc_ugt_yes		# unordered or greater than?
fscc_ugt_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ugt_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# ordered greater or less than:
#	_____
#	NANvZ
#
fscc_ogl:
	fbogl.w		fscc_ogl_yes		# ordered greater or less than?
fscc_ogl_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ogl_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# unordered or equal:
#
#	NANvZ
#
fscc_ueq:
	fbueq.w		fscc_ueq_yes		# unordered or equal?
fscc_ueq_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_ueq_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# ordered:
#	___
#	NAN
#
fscc_or:
	fbor.w		fscc_or_yes		# ordered?
fscc_or_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_or_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#
# unordered:
#
#	NAN
#
fscc_un:
	fbun.w		fscc_un_yes		# unordered?
fscc_un_no:
	clr.b		%d0			# set false
	bra.w		fscc_done		# go finish
fscc_un_yes:
	st		%d0			# set true
	bra.w		fscc_done		# go finish

#######################################################################

#
# the bsun exception bit was set. now, check to see is BSUN 
# is enabled. if so, don't store result and correct stack frame
# for a bsun exception.
#
fscc_chk_bsun:
	btst		&bsun_bit,FPCR_ENABLE(%a6) # was BSUN set?
	bne.w		fscc_bsun

#
# the bsun exception bit was not set.
# the result has been selected.
# now, check to see if the result is to be stored in the data register
# file or in memory.
#
fscc_done:
	mov.l		%d0,%a0			# save result for a moment

	mov.b		1+EXC_OPWORD(%a6),%d1	# fetch lo opword 
	mov.l		%d1,%d0			# make a copy
	andi.b		&0x38,%d1		# extract src mode

	bne.b		fscc_mem_op		# it's a memory operation

	mov.l		%d0,%d1
	andi.w		&0x7,%d1		# pass index in d1
	mov.l		%a0,%d0			# pass result in d0
	bsr.l		store_dreg_b		# save result in regfile
	rts

#
# the stacked <ea> is correct with the exception of:
# 	-> Dn : <ea> is garbage
#
# if the addressing mode is post-increment or pre-decrement,
# then the address registers have not been updated.
#
fscc_mem_op:
	cmpi.b		%d1,&0x18		# is <ea> (An)+ ?
	beq.b		fscc_mem_inc		# yes
	cmpi.b		%d1,&0x20		# is <ea> -(An) ?
	beq.b		fscc_mem_dec		# yes

	mov.l		%a0,%d0			# pass result in d0
	mov.l		EXC_EA(%a6),%a0		# fetch <ea>
	bsr.l		_dmem_write_byte	# write result byte	

	tst.l		%d1			# did dstore fail?
	bne.w		fscc_err		# yes

	rts

# addresing mode is post-increment. write the result byte. if the write
# fails then don't update the address register. if write passes then
# call inc_areg() to update the address register.
fscc_mem_inc:
	mov.l		%a0,%d0			# pass result in d0
	mov.l		EXC_EA(%a6),%a0		# fetch <ea>
	bsr.l		_dmem_write_byte	# write result byte

	tst.l		%d1			# did dstore fail?
	bne.w		fscc_err		# yes

	mov.b		0x1+EXC_OPWORD(%a6),%d1	# fetch opword
	andi.w		&0x7,%d1		# pass index in d1
	movq.l		&0x1,%d0		# pass amt to inc by
	bsr.l		inc_areg		# increment address register

	rts

# addressing mode is pre-decrement. write the result byte. if the write
# fails then don't update the address register. if the write passes then
# call dec_areg() to update the address register.
fscc_mem_dec:
	mov.l		%a0,%d0			# pass result in d0
	mov.l		EXC_EA(%a6),%a0		# fetch <ea>
	bsr.l		_dmem_write_byte	# write result byte

	tst.l		%d1			# did dstore fail?
	bne.w		fscc_err		# yes

	mov.b		0x1+EXC_OPWORD(%a6),%d1	# fetch opword
	andi.w		&0x7,%d1		# pass index in d1
	movq.l		&0x1,%d0		# pass amt to dec by
	bsr.l		dec_areg		# decrement address register

	rts

# the emulation routine set bsun and BSUN was enabled. have to
# fix stack and jump to the bsun handler.
# let the caller of this routine shift the stack frame up to
# eliminate the effective address field.
fscc_bsun:
	mov.b		&fbsun_flg,SPCOND_FLG(%a6)
	rts

# the byte write to memory has failed. pass the failing effective address
# and a FSLW to funimp_dacc().
fscc_err:
	mov.w		&0x00a1,EXC_VOFF(%a6)
	bra.l		facc_finish

#########################################################################
# XDEF ****************************************************************	#
#	fmovm_dynamic(): emulate "fmovm" dynamic instruction		#
#									#
# XREF ****************************************************************	#
#	fetch_dreg() - fetch data register				#
#	{i,d,}mem_read() - fetch data from memory			#
#	_mem_write() - write data to memory				#
#	iea_iacc() - instruction memory access error occurred		#
#	iea_dacc() - data memory access error occurred			#
#	restore() - restore An index regs if access error occurred	#
#									#
# INPUT ***************************************************************	#
#	None								#
# 									#
# OUTPUT **************************************************************	#
#	If instr is "fmovm Dn,-(A7)" from supervisor mode,		#
#		d0 = size of dump					#
#		d1 = Dn							#
#	Else if instruction access error,				#
#		d0 = FSLW						#
#	Else if data access error,					#
#		d0 = FSLW						#
#		a0 = address of fault					#
#	Else								#
#		none.							#
#									#
# ALGORITHM ***********************************************************	#
#	The effective address must be calculated since this is entered	#
# from an "Unimplemented Effective Address" exception handler. So, we	#
# have our own fcalc_ea() routine here. If an access error is flagged	#
# by a _{i,d,}mem_read() call, we must exit through the special		#
# handler.								#
#	The data register is determined and its value loaded to get the	#
# string of FP registers affected. This value is used as an index into	#
# a lookup table such that we can determine the number of bytes		#
# involved. 								#
#	If the instruction is "fmovm.x <ea>,Dn", a _mem_read() is used	#
# to read in all FP values. Again, _mem_read() may fail and require a	#
# special exit. 							#
#	If the instruction is "fmovm.x DN,<ea>", a _mem_write() is used	#
# to write all FP values. _mem_write() may also fail.			#
# 	If the instruction is "fmovm.x DN,-(a7)" from supervisor mode,	#
# then we return the size of the dump and the string to the caller	#
# so that the move can occur outside of this routine. This special	#
# case is required so that moves to the system stack are handled	#
# correctly.								#
#									#
# DYNAMIC:								#
# 	fmovm.x	dn, <ea>						#
# 	fmovm.x	<ea>, dn						#
#									#
#	      <WORD 1>		      <WORD2>				#
#	1111 0010 00 |<ea>|	11@& 1000 0$$$ 0000			#
#					  				#
#	& = (0): predecrement addressing mode				#
#	    (1): postincrement or control addressing mode		#
#	@ = (0): move listed regs from memory to the FPU		#
#	    (1): move listed regs from the FPU to memory		#
#	$$$    : index of data register holding reg select mask		#
#									#
# NOTES:								#
#	If the data register holds a zero, then the			#
#	instruction is a nop.						#
#									#
#########################################################################

	global		fmovm_dynamic
fmovm_dynamic:

# extract the data register in which the bit string resides...
	mov.b		1+EXC_EXTWORD(%a6),%d1	# fetch extword
	andi.w		&0x70,%d1		# extract reg bits
	lsr.b		&0x4,%d1		# shift into lo bits

# fetch the bit string into d0...
	bsr.l		fetch_dreg		# fetch reg string

	andi.l		&0x000000ff,%d0		# keep only lo byte

	mov.l		%d0,-(%sp)		# save strg
	mov.b		(tbl_fmovm_size.w,%pc,%d0),%d0
	mov.l		%d0,-(%sp)		# save size
	bsr.l		fmovm_calc_ea		# calculate <ea>
	mov.l		(%sp)+,%d0		# restore size
	mov.l		(%sp)+,%d1		# restore strg

# if the bit string is a zero, then the operation is a no-op
# but, make sure that we've calculated ea and advanced the opword pointer
	beq.w		fmovm_data_done

# separate move ins from move outs...
	btst		&0x5,EXC_EXTWORD(%a6)	# is it a move in or out?
	beq.w		fmovm_data_in		# it's a move out

#############
# MOVE OUT: #
#############
fmovm_data_out:
	btst		&0x4,EXC_EXTWORD(%a6)	# control or predecrement?
	bne.w		fmovm_out_ctrl		# control

############################
fmovm_out_predec:
# for predecrement mode, the bit string is the opposite of both control
# operations and postincrement mode. (bit7 = FP7 ... bit0 = FP0)
# here, we convert it to be just like the others...
	mov.b		(tbl_fmovm_convert.w,%pc,%d1.w*1),%d1

	btst		&0x5,EXC_SR(%a6)	# user or supervisor mode?
	beq.b		fmovm_out_ctrl		# user

fmovm_out_predec_s:
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg # is <ea> mode -(a7)?
	bne.b		fmovm_out_ctrl

# the operation was unfortunately an: fmovm.x dn,-(sp)
# called from supervisor mode.
# we're also passing "size" and "strg" back to the calling routine
	rts

############################
fmovm_out_ctrl:
	mov.l		%a0,%a1			# move <ea> to a1

	sub.l		%d0,%sp			# subtract size of dump
	lea		(%sp),%a0

	tst.b		%d1			# should FP0 be moved?
	bpl.b		fmovm_out_ctrl_fp1	# no

	mov.l		0x0+EXC_FP0(%a6),(%a0)+	# yes
	mov.l		0x4+EXC_FP0(%a6),(%a0)+
	mov.l		0x8+EXC_FP0(%a6),(%a0)+

fmovm_out_ctrl_fp1:
	lsl.b		&0x1,%d1		# should FP1 be moved?
	bpl.b		fmovm_out_ctrl_fp2	# no

	mov.l		0x0+EXC_FP1(%a6),(%a0)+	# yes
	mov.l		0x4+EXC_FP1(%a6),(%a0)+
	mov.l		0x8+EXC_FP1(%a6),(%a0)+

fmovm_out_ctrl_fp2:
	lsl.b		&0x1,%d1		# should FP2 be moved?
	bpl.b		fmovm_out_ctrl_fp3	# no

	fmovm.x		&0x20,(%a0)		# yes
	add.l		&0xc,%a0

fmovm_out_ctrl_fp3:
	lsl.b		&0x1,%d1		# should FP3 be moved?
	bpl.b		fmovm_out_ctrl_fp4	# no

	fmovm.x		&0x10,(%a0)		# yes
	add.l		&0xc,%a0

fmovm_out_ctrl_fp4:
	lsl.b		&0x1,%d1		# should FP4 be moved?
	bpl.b		fmovm_out_ctrl_fp5	# no

	fmovm.x		&0x08,(%a0)		# yes
	add.l		&0xc,%a0

fmovm_out_ctrl_fp5:
	lsl.b		&0x1,%d1		# should FP5 be moved?
	bpl.b		fmovm_out_ctrl_fp6	# no

	fmovm.x		&0x04,(%a0)		# yes
	add.l		&0xc,%a0

fmovm_out_ctrl_fp6:
	lsl.b		&0x1,%d1		# should FP6 be moved?
	bpl.b		fmovm_out_ctrl_fp7	# no

	fmovm.x		&0x02,(%a0)		# yes
	add.l		&0xc,%a0

fmovm_out_ctrl_fp7:
	lsl.b		&0x1,%d1		# should FP7 be moved?
	bpl.b		fmovm_out_ctrl_done	# no

	fmovm.x		&0x01,(%a0)		# yes
	add.l		&0xc,%a0

fmovm_out_ctrl_done:
	mov.l		%a1,L_SCR1(%a6)

	lea		(%sp),%a0		# pass: supervisor src
	mov.l		%d0,-(%sp)		# save size
	bsr.l		_dmem_write		# copy data to user mem

	mov.l		(%sp)+,%d0
	add.l		%d0,%sp			# clear fpreg data from stack

	tst.l		%d1			# did dstore err?
	bne.w		fmovm_out_err		# yes

	rts

############
# MOVE IN: #
############
fmovm_data_in:
	mov.l		%a0,L_SCR1(%a6)

	sub.l		%d0,%sp			# make room for fpregs
	lea		(%sp),%a1

	mov.l		%d1,-(%sp)		# save bit string for later
	mov.l		%d0,-(%sp)		# save # of bytes

	bsr.l		_dmem_read		# copy data from user mem

	mov.l		(%sp)+,%d0		# retrieve # of bytes

	tst.l		%d1			# did dfetch fail?
	bne.w		fmovm_in_err		# yes

	mov.l		(%sp)+,%d1		# load bit string

	lea		(%sp),%a0		# addr of stack

	tst.b		%d1			# should FP0 be moved?
	bpl.b		fmovm_data_in_fp1	# no

	mov.l		(%a0)+,0x0+EXC_FP0(%a6)	# yes
	mov.l		(%a0)+,0x4+EXC_FP0(%a6)
	mov.l		(%a0)+,0x8+EXC_FP0(%a6)

fmovm_data_in_fp1:
	lsl.b		&0x1,%d1		# should FP1 be moved?
	bpl.b		fmovm_data_in_fp2	# no

	mov.l		(%a0)+,0x0+EXC_FP1(%a6)	# yes
	mov.l		(%a0)+,0x4+EXC_FP1(%a6)
	mov.l		(%a0)+,0x8+EXC_FP1(%a6)

fmovm_data_in_fp2:
	lsl.b		&0x1,%d1		# should FP2 be moved?
	bpl.b		fmovm_data_in_fp3	# no

	fmovm.x		(%a0)+,&0x20		# yes

fmovm_data_in_fp3:
	lsl.b		&0x1,%d1		# should FP3 be moved?
	bpl.b		fmovm_data_in_fp4	# no

	fmovm.x		(%a0)+,&0x10		# yes

fmovm_data_in_fp4:
	lsl.b		&0x1,%d1		# should FP4 be moved?
	bpl.b		fmovm_data_in_fp5	# no

	fmovm.x		(%a0)+,&0x08		# yes

fmovm_data_in_fp5:
	lsl.b		&0x1,%d1		# should FP5 be moved?
	bpl.b		fmovm_data_in_fp6	# no

	fmovm.x		(%a0)+,&0x04		# yes

fmovm_data_in_fp6:
	lsl.b		&0x1,%d1		# should FP6 be moved?
	bpl.b		fmovm_data_in_fp7	# no

	fmovm.x		(%a0)+,&0x02		# yes

fmovm_data_in_fp7:
	lsl.b		&0x1,%d1		# should FP7 be moved?
	bpl.b		fmovm_data_in_done	# no

	fmovm.x		(%a0)+,&0x01		# yes

fmovm_data_in_done:
	add.l		%d0,%sp			# remove fpregs from stack
	rts

#####################################

fmovm_data_done:
	rts

##############################################################################

#
# table indexed by the operation's bit string that gives the number
# of bytes that will be moved.
#
# number of bytes = (# of 1's in bit string) * 12(bytes/fpreg)
#
tbl_fmovm_size:
	byte	0x00,0x0c,0x0c,0x18,0x0c,0x18,0x18,0x24
	byte	0x0c,0x18,0x18,0x24,0x18,0x24,0x24,0x30
	byte	0x0c,0x18,0x18,0x24,0x18,0x24,0x24,0x30
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x0c,0x18,0x18,0x24,0x18,0x24,0x24,0x30
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x0c,0x18,0x18,0x24,0x18,0x24,0x24,0x30
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x30,0x3c,0x3c,0x48,0x3c,0x48,0x48,0x54
	byte	0x0c,0x18,0x18,0x24,0x18,0x24,0x24,0x30
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x30,0x3c,0x3c,0x48,0x3c,0x48,0x48,0x54
	byte	0x18,0x24,0x24,0x30,0x24,0x30,0x30,0x3c
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x30,0x3c,0x3c,0x48,0x3c,0x48,0x48,0x54
	byte	0x24,0x30,0x30,0x3c,0x30,0x3c,0x3c,0x48
	byte	0x30,0x3c,0x3c,0x48,0x3c,0x48,0x48,0x54
	byte	0x30,0x3c,0x3c,0x48,0x3c,0x48,0x48,0x54
	byte	0x3c,0x48,0x48,0x54,0x48,0x54,0x54,0x60	

#
# table to convert a pre-decrement bit string into a post-increment
# or control bit string.
# ex: 	0x00	==>	0x00
#	0x01	==>	0x80
#	0x02	==>	0x40
#		.
#		.
#	0xfd	==>	0xbf
#	0xfe	==>	0x7f
#	0xff	==>	0xff
#
tbl_fmovm_convert:
	byte	0x00,0x80,0x40,0xc0,0x20,0xa0,0x60,0xe0
	byte	0x10,0x90,0x50,0xd0,0x30,0xb0,0x70,0xf0
	byte	0x08,0x88,0x48,0xc8,0x28,0xa8,0x68,0xe8
	byte	0x18,0x98,0x58,0xd8,0x38,0xb8,0x78,0xf8
	byte	0x04,0x84,0x44,0xc4,0x24,0xa4,0x64,0xe4
	byte	0x14,0x94,0x54,0xd4,0x34,0xb4,0x74,0xf4
	byte	0x0c,0x8c,0x4c,0xcc,0x2c,0xac,0x6c,0xec
	byte	0x1c,0x9c,0x5c,0xdc,0x3c,0xbc,0x7c,0xfc
	byte	0x02,0x82,0x42,0xc2,0x22,0xa2,0x62,0xe2
	byte	0x12,0x92,0x52,0xd2,0x32,0xb2,0x72,0xf2
	byte	0x0a,0x8a,0x4a,0xca,0x2a,0xaa,0x6a,0xea
	byte	0x1a,0x9a,0x5a,0xda,0x3a,0xba,0x7a,0xfa
	byte	0x06,0x86,0x46,0xc6,0x26,0xa6,0x66,0xe6
	byte	0x16,0x96,0x56,0xd6,0x36,0xb6,0x76,0xf6
	byte	0x0e,0x8e,0x4e,0xce,0x2e,0xae,0x6e,0xee
	byte	0x1e,0x9e,0x5e,0xde,0x3e,0xbe,0x7e,0xfe
	byte	0x01,0x81,0x41,0xc1,0x21,0xa1,0x61,0xe1
	byte	0x11,0x91,0x51,0xd1,0x31,0xb1,0x71,0xf1
	byte	0x09,0x89,0x49,0xc9,0x29,0xa9,0x69,0xe9
	byte	0x19,0x99,0x59,0xd9,0x39,0xb9,0x79,0xf9
	byte	0x05,0x85,0x45,0xc5,0x25,0xa5,0x65,0xe5
	byte	0x15,0x95,0x55,0xd5,0x35,0xb5,0x75,0xf5
	byte	0x0d,0x8d,0x4d,0xcd,0x2d,0xad,0x6d,0xed
	byte	0x1d,0x9d,0x5d,0xdd,0x3d,0xbd,0x7d,0xfd
	byte	0x03,0x83,0x43,0xc3,0x23,0xa3,0x63,0xe3
	byte	0x13,0x93,0x53,0xd3,0x33,0xb3,0x73,0xf3
	byte	0x0b,0x8b,0x4b,0xcb,0x2b,0xab,0x6b,0xeb
	byte	0x1b,0x9b,0x5b,0xdb,0x3b,0xbb,0x7b,0xfb
	byte	0x07,0x87,0x47,0xc7,0x27,0xa7,0x67,0xe7
	byte	0x17,0x97,0x57,0xd7,0x37,0xb7,0x77,0xf7
	byte	0x0f,0x8f,0x4f,0xcf,0x2f,0xaf,0x6f,0xef
	byte	0x1f,0x9f,0x5f,0xdf,0x3f,0xbf,0x7f,0xff

	global		fmovm_calc_ea
###############################################
# _fmovm_calc_ea: calculate effective address #
###############################################
fmovm_calc_ea:
	mov.l		%d0,%a0			# move # bytes to a0

# currently, MODE and REG are taken from the EXC_OPWORD. this could be
# easily changed if they were inputs passed in registers.
	mov.w		EXC_OPWORD(%a6),%d0	# fetch opcode word
	mov.w		%d0,%d1			# make a copy

	andi.w		&0x3f,%d0		# extract mode field
	andi.l		&0x7,%d1		# extract reg  field

# jump to the corresponding function for each {MODE,REG} pair.
	mov.w		(tbl_fea_mode.b,%pc,%d0.w*2),%d0 # fetch jmp distance
	jmp		(tbl_fea_mode.b,%pc,%d0.w*1) # jmp to correct ea mode

	swbeg		&64
tbl_fea_mode:
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode

	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode
	short		tbl_fea_mode	-	tbl_fea_mode

	short		faddr_ind_a0	- 	tbl_fea_mode
	short		faddr_ind_a1	- 	tbl_fea_mode
	short		faddr_ind_a2	- 	tbl_fea_mode
	short		faddr_ind_a3 	- 	tbl_fea_mode
	short		faddr_ind_a4 	- 	tbl_fea_mode
	short		faddr_ind_a5 	- 	tbl_fea_mode
	short		faddr_ind_a6 	- 	tbl_fea_mode
	short		faddr_ind_a7 	- 	tbl_fea_mode

	short		faddr_ind_p_a0	- 	tbl_fea_mode
	short		faddr_ind_p_a1 	- 	tbl_fea_mode
	short		faddr_ind_p_a2 	- 	tbl_fea_mode
	short		faddr_ind_p_a3 	- 	tbl_fea_mode
	short		faddr_ind_p_a4 	- 	tbl_fea_mode
	short		faddr_ind_p_a5 	- 	tbl_fea_mode
	short		faddr_ind_p_a6 	- 	tbl_fea_mode
	short		faddr_ind_p_a7 	- 	tbl_fea_mode

	short		faddr_ind_m_a0 	- 	tbl_fea_mode
	short		faddr_ind_m_a1 	- 	tbl_fea_mode
	short		faddr_ind_m_a2 	- 	tbl_fea_mode
	short		faddr_ind_m_a3 	- 	tbl_fea_mode
	short		faddr_ind_m_a4 	- 	tbl_fea_mode
	short		faddr_ind_m_a5 	- 	tbl_fea_mode
	short		faddr_ind_m_a6 	- 	tbl_fea_mode
	short		faddr_ind_m_a7 	- 	tbl_fea_mode

	short		faddr_ind_disp_a0	- 	tbl_fea_mode
	short		faddr_ind_disp_a1 	- 	tbl_fea_mode
	short		faddr_ind_disp_a2 	- 	tbl_fea_mode
	short		faddr_ind_disp_a3 	- 	tbl_fea_mode
	short		faddr_ind_disp_a4 	- 	tbl_fea_mode
	short		faddr_ind_disp_a5 	- 	tbl_fea_mode
	short		faddr_ind_disp_a6 	- 	tbl_fea_mode
	short		faddr_ind_disp_a7	-	tbl_fea_mode

	short		faddr_ind_ext 	- 	tbl_fea_mode
	short		faddr_ind_ext 	- 	tbl_fea_mode
	short		faddr_ind_ext 	- 	tbl_fea_mode
	short		faddr_ind_ext 	- 	tbl_fea_mode
	short		faddr_ind_ext 	- 	tbl_fea_mode
	short		faddr_ind_ext 	- 	tbl_fea_mode
	short		faddr_ind_ext 	- 	tbl_fea_mode
	short		faddr_ind_ext 	- 	tbl_fea_mode

	short		fabs_short	- 	tbl_fea_mode
	short		fabs_long	- 	tbl_fea_mode
	short		fpc_ind		- 	tbl_fea_mode
	short		fpc_ind_ext	- 	tbl_fea_mode
	short		tbl_fea_mode	- 	tbl_fea_mode
	short		tbl_fea_mode	- 	tbl_fea_mode
	short		tbl_fea_mode	- 	tbl_fea_mode
	short		tbl_fea_mode	- 	tbl_fea_mode

###################################
# Address register indirect: (An) #
###################################
faddr_ind_a0:
	mov.l		EXC_DREGS+0x8(%a6),%a0	# Get current a0
	rts

faddr_ind_a1:
	mov.l		EXC_DREGS+0xc(%a6),%a0	# Get current a1
	rts

faddr_ind_a2:
	mov.l		%a2,%a0			# Get current a2
	rts

faddr_ind_a3:
	mov.l		%a3,%a0			# Get current a3
	rts

faddr_ind_a4:
	mov.l		%a4,%a0			# Get current a4
	rts

faddr_ind_a5:
	mov.l		%a5,%a0			# Get current a5
	rts

faddr_ind_a6:
	mov.l		(%a6),%a0		# Get current a6
	rts

faddr_ind_a7:
	mov.l		EXC_A7(%a6),%a0		# Get current a7
	rts

#####################################################
# Address register indirect w/ postincrement: (An)+ #
#####################################################
faddr_ind_p_a0:
	mov.l		EXC_DREGS+0x8(%a6),%d0	# Get current a0
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,EXC_DREGS+0x8(%a6)	# Save incr value
	mov.l		%d0,%a0
	rts

faddr_ind_p_a1:
	mov.l		EXC_DREGS+0xc(%a6),%d0	# Get current a1
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,EXC_DREGS+0xc(%a6)	# Save incr value
	mov.l		%d0,%a0
	rts

faddr_ind_p_a2:
	mov.l		%a2,%d0			# Get current a2
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,%a2			# Save incr value
	mov.l		%d0,%a0
	rts

faddr_ind_p_a3:
	mov.l		%a3,%d0			# Get current a3
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,%a3			# Save incr value
	mov.l		%d0,%a0
	rts

faddr_ind_p_a4:
	mov.l		%a4,%d0			# Get current a4
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,%a4			# Save incr value
	mov.l		%d0,%a0
	rts

faddr_ind_p_a5:
	mov.l		%a5,%d0			# Get current a5
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,%a5			# Save incr value
	mov.l		%d0,%a0
	rts

faddr_ind_p_a6:
	mov.l		(%a6),%d0		# Get current a6
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,(%a6)		# Save incr value
	mov.l		%d0,%a0
	rts

faddr_ind_p_a7:
	mov.b		&mia7_flg,SPCOND_FLG(%a6) # set "special case" flag

	mov.l		EXC_A7(%a6),%d0		# Get current a7
	mov.l		%d0,%d1
	add.l		%a0,%d1			# Increment
	mov.l		%d1,EXC_A7(%a6)		# Save incr value
	mov.l		%d0,%a0
	rts

####################################################
# Address register indirect w/ predecrement: -(An) #
####################################################
faddr_ind_m_a0:
	mov.l		EXC_DREGS+0x8(%a6),%d0	# Get current a0
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,EXC_DREGS+0x8(%a6)	# Save decr value
	mov.l		%d0,%a0
	rts

faddr_ind_m_a1:
	mov.l		EXC_DREGS+0xc(%a6),%d0	# Get current a1
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,EXC_DREGS+0xc(%a6)	# Save decr value
	mov.l		%d0,%a0
	rts

faddr_ind_m_a2:
	mov.l		%a2,%d0			# Get current a2
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,%a2			# Save decr value
	mov.l		%d0,%a0
	rts

faddr_ind_m_a3:
	mov.l		%a3,%d0			# Get current a3
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,%a3			# Save decr value
	mov.l		%d0,%a0
	rts

faddr_ind_m_a4:
	mov.l		%a4,%d0			# Get current a4
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,%a4			# Save decr value
	mov.l		%d0,%a0
	rts

faddr_ind_m_a5:
	mov.l		%a5,%d0			# Get current a5
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,%a5			# Save decr value
	mov.l		%d0,%a0
	rts

faddr_ind_m_a6:
	mov.l		(%a6),%d0		# Get current a6
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,(%a6)		# Save decr value
	mov.l		%d0,%a0
	rts

faddr_ind_m_a7:
	mov.b		&mda7_flg,SPCOND_FLG(%a6) # set "special case" flag

	mov.l		EXC_A7(%a6),%d0		# Get current a7
	sub.l		%a0,%d0			# Decrement
	mov.l		%d0,EXC_A7(%a6)		# Save decr value
	mov.l		%d0,%a0
	rts

########################################################
# Address register indirect w/ displacement: (d16, An) #
########################################################
faddr_ind_disp_a0:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		EXC_DREGS+0x8(%a6),%a0	# a0 + d16
	rts

faddr_ind_disp_a1:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		EXC_DREGS+0xc(%a6),%a0	# a1 + d16
	rts

faddr_ind_disp_a2:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		%a2,%a0			# a2 + d16
	rts

faddr_ind_disp_a3:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		%a3,%a0			# a3 + d16
	rts

faddr_ind_disp_a4:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		%a4,%a0			# a4 + d16
	rts

faddr_ind_disp_a5:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		%a5,%a0			# a5 + d16
	rts

faddr_ind_disp_a6:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		(%a6),%a0		# a6 + d16
	rts

faddr_ind_disp_a7:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		EXC_A7(%a6),%a0		# a7 + d16
	rts

########################################################################
# Address register indirect w/ index(8-bit displacement): (d8, An, Xn) #
#    "       "         "    w/   "  (base displacement): (bd, An, Xn)  #
# Memory indirect postindexed: ([bd, An], Xn, od)		       #
# Memory indirect preindexed: ([bd, An, Xn], od)		       #
########################################################################
faddr_ind_ext:
	addq.l		&0x8,%d1
	bsr.l		fetch_dreg		# fetch base areg
	mov.l		%d0,-(%sp)

	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word		# fetch extword in d0

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		(%sp)+,%a0

	btst		&0x8,%d0
	bne.w		fcalc_mem_ind
	
	mov.l		%d0,L_SCR1(%a6)		# hold opword

	mov.l		%d0,%d1
	rol.w		&0x4,%d1
	andi.w		&0xf,%d1		# extract index regno

# count on fetch_dreg() not to alter a0...
	bsr.l		fetch_dreg		# fetch index

	mov.l		%d2,-(%sp)		# save d2
	mov.l		L_SCR1(%a6),%d2		# fetch opword

	btst		&0xb,%d2		# is it word or long?
	bne.b		faii8_long
	ext.l		%d0			# sign extend word index
faii8_long:
	mov.l		%d2,%d1
	rol.w		&0x7,%d1
	andi.l		&0x3,%d1		# extract scale value

	lsl.l		%d1,%d0			# shift index by scale

	extb.l		%d2			# sign extend displacement
	add.l		%d2,%d0			# index + disp
	add.l		%d0,%a0			# An + (index + disp)

	mov.l		(%sp)+,%d2		# restore old d2
	rts

###########################
# Absolute short: (XXX).W #
###########################
fabs_short:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word		# fetch short address

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# return <ea> in a0
	rts

##########################
# Absolute long: (XXX).L #
##########################
fabs_long:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch long address

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,%a0			# return <ea> in a0
	rts

#######################################################
# Program counter indirect w/ displacement: (d16, PC) #
#######################################################
fpc_ind:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word		# fetch word displacement

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.w		%d0,%a0			# sign extend displacement

	add.l		EXC_EXTWPTR(%a6),%a0	# pc + d16

# _imem_read_word() increased the extwptr by 2. need to adjust here.
	subq.l		&0x2,%a0		# adjust <ea>
	rts

##########################################################
# PC indirect w/ index(8-bit displacement): (d8, PC, An) #
# "     "     w/   "  (base displacement): (bd, PC, An)  #
# PC memory indirect postindexed: ([bd, PC], Xn, od)     #
# PC memory indirect preindexed: ([bd, PC, Xn], od)      #
##########################################################
fpc_ind_ext:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word		# fetch ext word

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		EXC_EXTWPTR(%a6),%a0	# put base in a0
	subq.l		&0x2,%a0		# adjust base

	btst		&0x8,%d0		# is disp only 8 bits?
	bne.w		fcalc_mem_ind		# calc memory indirect
	
	mov.l		%d0,L_SCR1(%a6)		# store opword

	mov.l		%d0,%d1			# make extword copy
	rol.w		&0x4,%d1		# rotate reg num into place
	andi.w		&0xf,%d1		# extract register number

# count on fetch_dreg() not to alter a0...
	bsr.l		fetch_dreg		# fetch index

	mov.l		%d2,-(%sp)		# save d2
	mov.l		L_SCR1(%a6),%d2		# fetch opword

	btst		&0xb,%d2		# is index word or long?
	bne.b		fpii8_long		# long
	ext.l		%d0			# sign extend word index
fpii8_long:
	mov.l		%d2,%d1
	rol.w		&0x7,%d1		# rotate scale value into place
	andi.l		&0x3,%d1		# extract scale value

	lsl.l		%d1,%d0			# shift index by scale

	extb.l		%d2			# sign extend displacement
	add.l		%d2,%d0			# disp + index
	add.l		%d0,%a0			# An + (index + disp)

	mov.l		(%sp)+,%d2		# restore temp register
	rts

# d2 = index
# d3 = base
# d4 = od
# d5 = extword
fcalc_mem_ind:
	btst		&0x6,%d0		# is the index suppressed?
	beq.b		fcalc_index

	movm.l		&0x3c00,-(%sp)		# save d2-d5

	mov.l		%d0,%d5			# put extword in d5
	mov.l		%a0,%d3			# put base in d3

	clr.l		%d2			# yes, so index = 0
	bra.b		fbase_supp_ck

# index:
fcalc_index:
	mov.l		%d0,L_SCR1(%a6)		# save d0 (opword)
	bfextu		%d0{&16:&4},%d1		# fetch dreg index
	bsr.l		fetch_dreg

	movm.l		&0x3c00,-(%sp)		# save d2-d5
	mov.l		%d0,%d2			# put index in d2
	mov.l		L_SCR1(%a6),%d5
	mov.l		%a0,%d3

	btst		&0xb,%d5		# is index word or long?
	bne.b		fno_ext
	ext.l		%d2

fno_ext:
	bfextu		%d5{&21:&2},%d0
	lsl.l		%d0,%d2

# base address (passed as parameter in d3):
# we clear the value here if it should actually be suppressed.
fbase_supp_ck:
	btst		&0x7,%d5		# is the bd suppressed?
	beq.b		fno_base_sup
	clr.l		%d3

# base displacement:
fno_base_sup:
	bfextu		%d5{&26:&2},%d0		# get bd size
#	beq.l		fmovm_error		# if (size == 0) it's reserved

	cmpi.b	 	%d0,&0x2
	blt.b		fno_bd
	beq.b		fget_word_bd

	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long

	tst.l		%d1			# did ifetch fail?
	bne.l		fcea_iacc		# yes

	bra.b		fchk_ind

fget_word_bd:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		fcea_iacc		# yes

	ext.l		%d0			# sign extend bd
	
fchk_ind:
	add.l		%d0,%d3			# base += bd

# outer displacement:
fno_bd:
	bfextu		%d5{&30:&2},%d0		# is od suppressed?
	beq.w		faii_bd

	cmpi.b	 	%d0,&0x2
	blt.b		fnull_od
	beq.b		fword_od
	
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long

	tst.l		%d1			# did ifetch fail?
	bne.l		fcea_iacc		# yes

	bra.b 		fadd_them

fword_od:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x2,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_word

	tst.l		%d1			# did ifetch fail?
	bne.l		fcea_iacc		# yes

	ext.l		%d0			# sign extend od
	bra.b		fadd_them

fnull_od:
	clr.l		%d0

fadd_them:
	mov.l		%d0,%d4

	btst		&0x2,%d5		# pre or post indexing?
	beq.b		fpre_indexed

	mov.l		%d3,%a0
	bsr.l		_dmem_read_long

	tst.l		%d1			# did dfetch fail?
	bne.w		fcea_err		# yes

	add.l		%d2,%d0			# <ea> += index
	add.l		%d4,%d0			# <ea> += od
	bra.b		fdone_ea

fpre_indexed:
	add.l		%d2,%d3			# preindexing
	mov.l		%d3,%a0
	bsr.l		_dmem_read_long

	tst.l		%d1			# did dfetch fail?
	bne.w		fcea_err		# yes

	add.l		%d4,%d0			# ea += od
	bra.b		fdone_ea

faii_bd:
	add.l		%d2,%d3			# ea = (base + bd) + index
	mov.l		%d3,%d0
fdone_ea:
	mov.l		%d0,%a0

	movm.l		(%sp)+,&0x003c		# restore d2-d5
	rts

#########################################################
fcea_err:	
	mov.l		%d3,%a0

	movm.l		(%sp)+,&0x003c		# restore d2-d5
	mov.w		&0x0101,%d0
	bra.l		iea_dacc

fcea_iacc:
	movm.l		(%sp)+,&0x003c		# restore d2-d5
	bra.l		iea_iacc
	
fmovm_out_err:
	bsr.l		restore
	mov.w		&0x00e1,%d0
	bra.b		fmovm_err

fmovm_in_err:
	bsr.l		restore
	mov.w		&0x0161,%d0

fmovm_err:
	mov.l		L_SCR1(%a6),%a0
	bra.l		iea_dacc

#########################################################################
# XDEF ****************************************************************	#
# 	fmovm_ctrl(): emulate fmovm.l of control registers instr	#
#									#
# XREF ****************************************************************	#
#	_imem_read_long() - read longword from memory			#
#	iea_iacc() - _imem_read_long() failed; error recovery		#
#									#
# INPUT ***************************************************************	#
#	None								#
# 									#
# OUTPUT **************************************************************	#
#	If _imem_read_long() doesn't fail:				#
#		USER_FPCR(a6)  = new FPCR value				#
#		USER_FPSR(a6)  = new FPSR value				#
#		USER_FPIAR(a6) = new FPIAR value			#
#									#
# ALGORITHM ***********************************************************	#
# 	Decode the instruction type by looking at the extension word 	#
# in order to see how many control registers to fetch from memory.	#
# Fetch them using _imem_read_long(). If this fetch fails, exit through	#
# the special access error exit handler iea_iacc().			#
#									#
# Instruction word decoding:						#
#									#
# 	fmovem.l #<data>, {FPIAR&|FPCR&|FPSR}				#
#									#
#		WORD1			WORD2				#
#	1111 0010 00 111100	100$ $$00 0000 0000			#
#									#
#	$$$ (100): FPCR							#
#	    (010): FPSR							#
#	    (001): FPIAR						#
#	    (000): FPIAR						#
#									#
#########################################################################

	global		fmovm_ctrl
fmovm_ctrl:
	mov.b		EXC_EXTWORD(%a6),%d0	# fetch reg select bits
	cmpi.b		%d0,&0x9c		# fpcr & fpsr & fpiar ?
	beq.w		fctrl_in_7		# yes
	cmpi.b		%d0,&0x98		# fpcr & fpsr ?
	beq.w		fctrl_in_6		# yes
	cmpi.b		%d0,&0x94		# fpcr & fpiar ?
	beq.b		fctrl_in_5		# yes
	
# fmovem.l #<data>, fpsr/fpiar
fctrl_in_3:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPSR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPSR(%a6)	# store new FPSR to stack
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPIAR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPIAR(%a6)	# store new FPIAR to stack
	rts

# fmovem.l #<data>, fpcr/fpiar
fctrl_in_5:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPCR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPCR(%a6)	# store new FPCR to stack
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPIAR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPIAR(%a6)	# store new FPIAR to stack
	rts

# fmovem.l #<data>, fpcr/fpsr
fctrl_in_6:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPCR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPCR(%a6)	# store new FPCR to mem
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPSR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPSR(%a6)	# store new FPSR to mem
	rts

# fmovem.l #<data>, fpcr/fpsr/fpiar
fctrl_in_7:
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPCR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPCR(%a6)	# store new FPCR to mem
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPSR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPSR(%a6)	# store new FPSR to mem
	mov.l		EXC_EXTWPTR(%a6),%a0	# fetch instruction addr
	addq.l		&0x4,EXC_EXTWPTR(%a6)	# incr instruction ptr
	bsr.l		_imem_read_long		# fetch FPIAR from mem

	tst.l		%d1			# did ifetch fail?
	bne.l		iea_iacc		# yes

	mov.l		%d0,USER_FPIAR(%a6)	# store new FPIAR to mem
	rts

#########################################################################
# XDEF ****************************************************************	#
#	_dcalc_ea(): calc correct <ea> from <ea> stacked on exception	#
#									#
# XREF ****************************************************************	#
#	inc_areg() - increment an address register			#
#	dec_areg() - decrement an address register			#
#									#
# INPUT ***************************************************************	#
#	d0 = number of bytes to adjust <ea> by				#
# 									#
# OUTPUT **************************************************************	#
#	None								#
#									#
# ALGORITHM ***********************************************************	#
# "Dummy" CALCulate Effective Address:					#
# 	The stacked <ea> for FP unimplemented instructions and opclass	#
#	two packed instructions is correct with the exception of...	#
#									#
#	1) -(An)   : The register is not updated regardless of size.	#
#		     Also, for extended precision and packed, the 	#
#		     stacked <ea> value is 8 bytes too big		#
#	2) (An)+   : The register is not updated.			#
#	3) #<data> : The upper longword of the immediate operand is 	#
#		     stacked b,w,l and s sizes are completely stacked. 	#
#		     d,x, and p are not.				#
#									#
#########################################################################

	global		_dcalc_ea
_dcalc_ea:
	mov.l		%d0, %a0		# move # bytes to %a0

	mov.b		1+EXC_OPWORD(%a6), %d0	# fetch opcode word
	mov.l		%d0, %d1		# make a copy

	andi.w		&0x38, %d0		# extract mode field
	andi.l		&0x7, %d1		# extract reg  field

	cmpi.b		%d0,&0x18		# is mode (An)+ ?
	beq.b		dcea_pi			# yes

	cmpi.b		%d0,&0x20		# is mode -(An) ?
	beq.b		dcea_pd			# yes

	or.w		%d1,%d0			# concat mode,reg
	cmpi.b		%d0,&0x3c		# is mode #<data>?

	beq.b		dcea_imm		# yes

	mov.l		EXC_EA(%a6),%a0		# return <ea>
	rts

# need to set immediate data flag here since we'll need to do
# an imem_read to fetch this later.
dcea_imm:
	mov.b		&immed_flg,SPCOND_FLG(%a6)
	lea		([USER_FPIAR,%a6],0x4),%a0 # no; return <ea>
	rts

# here, the <ea> is stacked correctly. however, we must update the 
# address register...	
dcea_pi:
	mov.l		%a0,%d0			# pass amt to inc by
	bsr.l		inc_areg		# inc addr register

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	rts

# the <ea> is stacked correctly for all but extended and packed which 
# the <ea>s are 8 bytes too large.
# it would make no sense to have a pre-decrement to a7 in supervisor
# mode so we don't even worry about this tricky case here : )
dcea_pd:
	mov.l		%a0,%d0			# pass amt to dec by
	bsr.l		dec_areg		# dec addr register

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct

	cmpi.b		%d0,&0xc		# is opsize ext or packed?
	beq.b		dcea_pd2		# yes
	rts
dcea_pd2:
	sub.l		&0x8,%a0		# correct <ea>
	mov.l		%a0,EXC_EA(%a6)		# put correct <ea> on stack
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	_calc_ea_fout(): calculate correct stacked <ea> for extended	#
#			 and packed data opclass 3 operations.		#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	None								#
# 									#
# OUTPUT **************************************************************	#
#	a0 = return correct effective address				#
#									#
# ALGORITHM ***********************************************************	#
#	For opclass 3 extended and packed data operations, the <ea>	#
# stacked for the exception is incorrect for -(an) and (an)+ addressing	#
# modes. Also, while we're at it, the index register itself must get 	#
# updated.								#
# 	So, for -(an), we must subtract 8 off of the stacked <ea> value	#
# and return that value as the correct <ea> and store that value in An.	#
# For (an)+, the stacked <ea> is correct but we must adjust An by +12.	#
#									#
#########################################################################

# This calc_ea is currently used to retrieve the correct <ea> 
# for fmove outs of type extended and packed.
	global		_calc_ea_fout
_calc_ea_fout:
	mov.b		1+EXC_OPWORD(%a6),%d0	# fetch opcode word
	mov.l		%d0,%d1			# make a copy

	andi.w		&0x38,%d0		# extract mode field
	andi.l		&0x7,%d1		# extract reg  field

	cmpi.b		%d0,&0x18		# is mode (An)+ ?
	beq.b		ceaf_pi			# yes

	cmpi.b		%d0,&0x20		# is mode -(An) ?
	beq.w		ceaf_pd			# yes

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	rts

# (An)+ : extended and packed fmove out
#	: stacked <ea> is correct
#	: "An" not updated 
ceaf_pi:
	mov.w		(tbl_ceaf_pi.b,%pc,%d1.w*2),%d1
	mov.l		EXC_EA(%a6),%a0
	jmp		(tbl_ceaf_pi.b,%pc,%d1.w*1)

	swbeg		&0x8
tbl_ceaf_pi:
	short		ceaf_pi0 - tbl_ceaf_pi
	short		ceaf_pi1 - tbl_ceaf_pi
	short		ceaf_pi2 - tbl_ceaf_pi
	short		ceaf_pi3 - tbl_ceaf_pi
	short		ceaf_pi4 - tbl_ceaf_pi
	short		ceaf_pi5 - tbl_ceaf_pi
	short		ceaf_pi6 - tbl_ceaf_pi
	short		ceaf_pi7 - tbl_ceaf_pi

ceaf_pi0:
	addi.l		&0xc,EXC_DREGS+0x8(%a6)
	rts
ceaf_pi1:
	addi.l		&0xc,EXC_DREGS+0xc(%a6)
	rts
ceaf_pi2:
	add.l		&0xc,%a2
	rts
ceaf_pi3:
	add.l		&0xc,%a3
	rts
ceaf_pi4:
	add.l		&0xc,%a4
	rts
ceaf_pi5:
	add.l		&0xc,%a5
	rts
ceaf_pi6:
	addi.l		&0xc,EXC_A6(%a6)
	rts
ceaf_pi7:
	mov.b		&mia7_flg,SPCOND_FLG(%a6)
	addi.l		&0xc,EXC_A7(%a6)
	rts

# -(An) : extended and packed fmove out
#	: stacked <ea> = actual <ea> + 8
#	: "An" not updated
ceaf_pd:
	mov.w		(tbl_ceaf_pd.b,%pc,%d1.w*2),%d1
	mov.l		EXC_EA(%a6),%a0
	sub.l		&0x8,%a0
	sub.l		&0x8,EXC_EA(%a6)
	jmp		(tbl_ceaf_pd.b,%pc,%d1.w*1)

	swbeg		&0x8
tbl_ceaf_pd:
	short		ceaf_pd0 - tbl_ceaf_pd
	short		ceaf_pd1 - tbl_ceaf_pd
	short		ceaf_pd2 - tbl_ceaf_pd
	short		ceaf_pd3 - tbl_ceaf_pd
	short		ceaf_pd4 - tbl_ceaf_pd
	short		ceaf_pd5 - tbl_ceaf_pd
	short		ceaf_pd6 - tbl_ceaf_pd
	short		ceaf_pd7 - tbl_ceaf_pd

ceaf_pd0:
	mov.l		%a0,EXC_DREGS+0x8(%a6)
	rts
ceaf_pd1:
	mov.l		%a0,EXC_DREGS+0xc(%a6)
	rts
ceaf_pd2:
	mov.l		%a0,%a2
	rts
ceaf_pd3:
	mov.l		%a0,%a3
	rts
ceaf_pd4:
	mov.l		%a0,%a4
	rts
ceaf_pd5:
	mov.l		%a0,%a5
	rts
ceaf_pd6:
	mov.l		%a0,EXC_A6(%a6)
	rts
ceaf_pd7:
	mov.l		%a0,EXC_A7(%a6)
	mov.b		&mda7_flg,SPCOND_FLG(%a6)
	rts

#########################################################################
# XDEF ****************************************************************	#
#	_load_fop(): load operand for unimplemented FP exception	#
#									#
# XREF ****************************************************************	#
#	set_tag_x() - determine ext prec optype tag			#
#	set_tag_s() - determine sgl prec optype tag			#
#	set_tag_d() - determine dbl prec optype tag			#
#	unnorm_fix() - convert normalized number to denorm or zero	#
#	norm() - normalize a denormalized number			#
#	get_packed() - fetch a packed operand from memory		#
#	_dcalc_ea() - calculate <ea>, fixing An in process		#
#									#
#	_imem_read_{word,long}() - read from instruction memory		#
#	_dmem_read() - read from data memory				#
#	_dmem_read_{byte,word,long}() - read from data memory		#
#									#
#	facc_in_{b,w,l,d,x}() - mem read failed; special exit point	#
#									#
# INPUT ***************************************************************	#
#	None								#
# 									#
# OUTPUT **************************************************************	#
#	If memory access doesn't fail:					#
#		FP_SRC(a6) = source operand in extended precision	#
# 		FP_DST(a6) = destination operand in extended precision	#
#									#
# ALGORITHM ***********************************************************	#
# 	This is called from the Unimplemented FP exception handler in	#
# order to load the source and maybe destination operand into		#
# FP_SRC(a6) and FP_DST(a6). If the instruction was opclass zero, load	#
# the source and destination from the FP register file. Set the optype	#
# tags for both if dyadic, one for monadic. If a number is an UNNORM,	#
# convert it to a DENORM or a ZERO.					#
# 	If the instruction is opclass two (memory->reg), then fetch	#
# the destination from the register file and the source operand from 	#
# memory. Tag and fix both as above w/ opclass zero instructions.	#
# 	If the source operand is byte,word,long, or single, it may be	#
# in the data register file. If it's actually out in memory, use one of	#
# the mem_read() routines to fetch it. If the mem_read() access returns	#
# a failing value, exit through the special facc_in() routine which	#
# will create an access error exception frame from the current exception #
# frame.								#
# 	Immediate data and regular data accesses are separated because 	#
# if an immediate data access fails, the resulting fault status		#
# longword stacked for the access error exception must have the 	#
# instruction bit set.							#
#									#
#########################################################################

	global		_load_fop
_load_fop:

#  15     13 12 10  9 7  6       0
# /        \ /   \ /  \ /         \
# ---------------------------------
# | opclass | RX  | RY | EXTENSION |  (2nd word of general FP instruction)
# ---------------------------------
#

#	bfextu		EXC_CMDREG(%a6){&0:&3}, %d0 # extract opclass
#	cmpi.b		%d0, &0x2		# which class is it? ('000,'010,'011)
#	beq.w		op010			# handle <ea> -> fpn
#	bgt.w		op011			# handle fpn -> <ea>

# we're not using op011 for now...
	btst		&0x6,EXC_CMDREG(%a6)
	bne.b		op010

############################
# OPCLASS '000: reg -> reg #
############################
op000:
	mov.b		1+EXC_CMDREG(%a6),%d0	# fetch extension word lo
	btst		&0x5,%d0		# testing extension bits
	beq.b		op000_src		# (bit 5 == 0) => monadic
	btst		&0x4,%d0		# (bit 5 == 1)
	beq.b		op000_dst		# (bit 4 == 0) => dyadic
	and.w		&0x007f,%d0		# extract extension bits {6:0}
	cmpi.w		%d0,&0x0038		# is it an fcmp (dyadic) ?
	bne.b		op000_src		# it's an fcmp

op000_dst:
	bfextu		EXC_CMDREG(%a6){&6:&3}, %d0 # extract dst field
	bsr.l		load_fpn2		# fetch dst fpreg into FP_DST

	bsr.l		set_tag_x		# get dst optype tag

	cmpi.b		%d0, &UNNORM		# is dst fpreg an UNNORM?
	beq.b		op000_dst_unnorm	# yes
op000_dst_cont:
	mov.b 		%d0, DTAG(%a6)		# store the dst optype tag

op000_src:
	bfextu		EXC_CMDREG(%a6){&3:&3}, %d0 # extract src field
	bsr.l		load_fpn1		# fetch src fpreg into FP_SRC

	bsr.l		set_tag_x		# get src optype tag

	cmpi.b		%d0, &UNNORM		# is src fpreg an UNNORM?
	beq.b		op000_src_unnorm	# yes
op000_src_cont:
	mov.b		%d0, STAG(%a6)		# store the src optype tag
	rts

op000_dst_unnorm:
	bsr.l		unnorm_fix		# fix the dst UNNORM
	bra.b		op000_dst_cont
op000_src_unnorm:
	bsr.l		unnorm_fix		# fix the src UNNORM
	bra.b		op000_src_cont

#############################
# OPCLASS '010: <ea> -> reg #
#############################
op010:
	mov.w		EXC_CMDREG(%a6),%d0	# fetch extension word
	btst		&0x5,%d0		# testing extension bits
	beq.b		op010_src		# (bit 5 == 0) => monadic
	btst		&0x4,%d0		# (bit 5 == 1)
	beq.b		op010_dst		# (bit 4 == 0) => dyadic
	and.w		&0x007f,%d0		# extract extension bits {6:0}
	cmpi.w		%d0,&0x0038		# is it an fcmp (dyadic) ?
	bne.b		op010_src		# it's an fcmp

op010_dst:
	bfextu		EXC_CMDREG(%a6){&6:&3}, %d0 # extract dst field
	bsr.l		load_fpn2		# fetch dst fpreg ptr

	bsr.l		set_tag_x		# get dst type tag

	cmpi.b		%d0, &UNNORM		# is dst fpreg an UNNORM?
	beq.b		op010_dst_unnorm	# yes
op010_dst_cont:
	mov.b		%d0, DTAG(%a6)		# store the dst optype tag

op010_src:
	bfextu		EXC_CMDREG(%a6){&3:&3}, %d0 # extract src type field

	bfextu		EXC_OPWORD(%a6){&10:&3}, %d1 # extract <ea> mode field
	bne.w		fetch_from_mem		# src op is in memory

op010_dreg:
	clr.b		STAG(%a6)		# either NORM or ZERO
	bfextu		EXC_OPWORD(%a6){&13:&3}, %d1 # extract src reg field

	mov.w		(tbl_op010_dreg.b,%pc,%d0.w*2), %d0 # jmp based on optype
	jmp		(tbl_op010_dreg.b,%pc,%d0.w*1) # fetch src from dreg

op010_dst_unnorm:
	bsr.l		unnorm_fix		# fix the dst UNNORM
	bra.b		op010_dst_cont

	swbeg		&0x8
tbl_op010_dreg:
	short		opd_long	- tbl_op010_dreg
	short		opd_sgl 	- tbl_op010_dreg
	short		tbl_op010_dreg	- tbl_op010_dreg
	short		tbl_op010_dreg	- tbl_op010_dreg
	short		opd_word	- tbl_op010_dreg
	short		tbl_op010_dreg	- tbl_op010_dreg
	short		opd_byte	- tbl_op010_dreg
	short		tbl_op010_dreg	- tbl_op010_dreg

#
# LONG: can be either NORM or ZERO...
#
opd_long:
	bsr.l		fetch_dreg		# fetch long in d0
	fmov.l		%d0, %fp0 		# load a long
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC
	fbeq.w		opd_long_zero		# long is a ZERO
	rts
opd_long_zero:
	mov.b		&ZERO, STAG(%a6)	# set ZERO optype flag
	rts

#
# WORD: can be either NORM or ZERO...
#
opd_word:
	bsr.l		fetch_dreg		# fetch word in d0
	fmov.w		%d0, %fp0 		# load a word
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC
	fbeq.w		opd_word_zero		# WORD is a ZERO
	rts
opd_word_zero:
	mov.b		&ZERO, STAG(%a6)	# set ZERO optype flag
	rts

#
# BYTE: can be either NORM or ZERO...
#
opd_byte:
	bsr.l		fetch_dreg		# fetch word in d0
	fmov.b		%d0, %fp0 		# load a byte
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC
	fbeq.w		opd_byte_zero		# byte is a ZERO
	rts
opd_byte_zero:
	mov.b		&ZERO, STAG(%a6)	# set ZERO optype flag
	rts

#
# SGL: can be either NORM, DENORM, ZERO, INF, QNAN or SNAN but not UNNORM
#
# separate SNANs and DENORMs so they can be loaded w/ special care.
# all others can simply be moved "in" using fmove.
#
opd_sgl:
	bsr.l		fetch_dreg		# fetch sgl in d0
	mov.l		%d0,L_SCR1(%a6)

	lea		L_SCR1(%a6), %a0 	# pass: ptr to the sgl
	bsr.l		set_tag_s		# determine sgl type
	mov.b		%d0, STAG(%a6)		# save the src tag

	cmpi.b		%d0, &SNAN		# is it an SNAN?
	beq.w		get_sgl_snan		# yes

	cmpi.b		%d0, &DENORM		# is it a DENORM?
	beq.w		get_sgl_denorm		# yes

	fmov.s		(%a0), %fp0		# no, so can load it regular
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC
	rts

##############################################################################

#########################################################################
# fetch_from_mem():							#
# - src is out in memory. must:						#
#	(1) calc ea - must read AFTER you know the src type since	#
#		      if the ea is -() or ()+, need to know # of bytes.	#
#	(2) read it in from either user or supervisor space		#
#	(3) if (b || w || l) then simply read in			#
#	    if (s || d || x) then check for SNAN,UNNORM,DENORM		#
#	    if (packed) then punt for now				#
# INPUT:								#
#	%d0 : src type field						#
#########################################################################
fetch_from_mem:
	clr.b		STAG(%a6)		# either NORM or ZERO

	mov.w		(tbl_fp_type.b,%pc,%d0.w*2), %d0 # index by src type field
	jmp		(tbl_fp_type.b,%pc,%d0.w*1)

	swbeg		&0x8
tbl_fp_type:
	short		load_long	- tbl_fp_type
	short		load_sgl	- tbl_fp_type
	short		load_ext	- tbl_fp_type
	short		load_packed	- tbl_fp_type
	short		load_word	- tbl_fp_type
	short		load_dbl	- tbl_fp_type
	short		load_byte	- tbl_fp_type
	short		tbl_fp_type	- tbl_fp_type

#########################################
# load a LONG into %fp0:		#
# 	-number can't fault		#
#	(1) calc ea			#
#	(2) read 4 bytes into L_SCR1	#
#	(3) fmov.l into %fp0		#
#########################################
load_long:
	movq.l		&0x4, %d0		# pass: 4 (bytes)
	bsr.l		_dcalc_ea		# calc <ea>; <ea> in %a0

	cmpi.b		SPCOND_FLG(%a6),&immed_flg
	beq.b		load_long_immed

	bsr.l		_dmem_read_long		# fetch src operand from memory

	tst.l		%d1			# did dfetch fail?
	bne.l		facc_in_l		# yes

load_long_cont:
	fmov.l		%d0, %fp0		# read into %fp0;convert to xprec
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC

	fbeq.w		load_long_zero		# src op is a ZERO
	rts
load_long_zero:
	mov.b		&ZERO, STAG(%a6)	# set optype tag to ZERO
	rts

load_long_immed:
	bsr.l		_imem_read_long		# fetch src operand immed data

	tst.l		%d1			# did ifetch fail?
	bne.l		funimp_iacc		# yes
	bra.b		load_long_cont

#########################################
# load a WORD into %fp0:		#
# 	-number can't fault		#
#	(1) calc ea			#
#	(2) read 2 bytes into L_SCR1	#
#	(3) fmov.w into %fp0		#
#########################################
load_word:
	movq.l		&0x2, %d0		# pass: 2 (bytes)
	bsr.l		_dcalc_ea		# calc <ea>; <ea> in %a0

	cmpi.b		SPCOND_FLG(%a6),&immed_flg
	beq.b		load_word_immed

	bsr.l		_dmem_read_word		# fetch src operand from memory

	tst.l		%d1			# did dfetch fail?
	bne.l		facc_in_w		# yes

load_word_cont:
	fmov.w		%d0, %fp0		# read into %fp0;convert to xprec
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC

	fbeq.w		load_word_zero		# src op is a ZERO
	rts
load_word_zero:
	mov.b		&ZERO, STAG(%a6)	# set optype tag to ZERO
	rts

load_word_immed:
	bsr.l		_imem_read_word		# fetch src operand immed data

	tst.l		%d1			# did ifetch fail?
	bne.l		funimp_iacc		# yes
	bra.b		load_word_cont

#########################################
# load a BYTE into %fp0:		#
# 	-number can't fault		#
#	(1) calc ea			#
#	(2) read 1 byte into L_SCR1	#
#	(3) fmov.b into %fp0		#
#########################################
load_byte:
	movq.l		&0x1, %d0		# pass: 1 (byte)
	bsr.l		_dcalc_ea		# calc <ea>; <ea> in %a0

	cmpi.b		SPCOND_FLG(%a6),&immed_flg
	beq.b		load_byte_immed

	bsr.l		_dmem_read_byte		# fetch src operand from memory

	tst.l		%d1			# did dfetch fail?
	bne.l		facc_in_b		# yes

load_byte_cont:
	fmov.b		%d0, %fp0		# read into %fp0;convert to xprec
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC

	fbeq.w		load_byte_zero		# src op is a ZERO
	rts
load_byte_zero:
	mov.b		&ZERO, STAG(%a6)	# set optype tag to ZERO
	rts

load_byte_immed:
	bsr.l		_imem_read_word		# fetch src operand immed data

	tst.l		%d1			# did ifetch fail?
	bne.l		funimp_iacc		# yes
	bra.b		load_byte_cont

#########################################
# load a SGL into %fp0:			#
# 	-number can't fault		#
#	(1) calc ea			#
#	(2) read 4 bytes into L_SCR1	#
#	(3) fmov.s into %fp0		#
#########################################
load_sgl:
	movq.l		&0x4, %d0		# pass: 4 (bytes)
	bsr.l		_dcalc_ea		# calc <ea>; <ea> in %a0

	cmpi.b		SPCOND_FLG(%a6),&immed_flg
	beq.b		load_sgl_immed

	bsr.l		_dmem_read_long		# fetch src operand from memory
	mov.l		%d0, L_SCR1(%a6)	# store src op on stack

	tst.l		%d1			# did dfetch fail?
	bne.l		facc_in_l		# yes

load_sgl_cont:
	lea		L_SCR1(%a6), %a0	# pass: ptr to sgl src op
	bsr.l		set_tag_s		# determine src type tag
	mov.b		%d0, STAG(%a6)		# save src optype tag on stack

	cmpi.b		%d0, &DENORM		# is it a sgl DENORM?
	beq.w		get_sgl_denorm		# yes

	cmpi.b		%d0, &SNAN		# is it a sgl SNAN?
	beq.w		get_sgl_snan		# yes

	fmov.s		L_SCR1(%a6), %fp0	# read into %fp0;convert to xprec
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC
	rts

load_sgl_immed:
	bsr.l		_imem_read_long		# fetch src operand immed data

	tst.l		%d1			# did ifetch fail?
	bne.l		funimp_iacc		# yes
	bra.b		load_sgl_cont

# must convert sgl denorm format to an Xprec denorm fmt suitable for 
# normalization...
# %a0 : points to sgl denorm
get_sgl_denorm:
	clr.w		FP_SRC_EX(%a6)
	bfextu		(%a0){&9:&23}, %d0	# fetch sgl hi(_mantissa)
	lsl.l		&0x8, %d0
	mov.l		%d0, FP_SRC_HI(%a6)	# set ext hi(_mantissa)
	clr.l		FP_SRC_LO(%a6)		# set ext lo(_mantissa)

	clr.w		FP_SRC_EX(%a6)
	btst		&0x7, (%a0)		# is sgn bit set?
	beq.b		sgl_dnrm_norm
	bset		&0x7, FP_SRC_EX(%a6)	# set sgn of xprec value

sgl_dnrm_norm:
	lea		FP_SRC(%a6), %a0
	bsr.l		norm			# normalize number
	mov.w		&0x3f81, %d1		# xprec exp = 0x3f81
	sub.w		%d0, %d1		# exp = 0x3f81 - shft amt.
	or.w		%d1, FP_SRC_EX(%a6)	# {sgn,exp}

	mov.b		&NORM, STAG(%a6)	# fix src type tag
	rts

# convert sgl to ext SNAN
# %a0 : points to sgl SNAN
get_sgl_snan:
	mov.w		&0x7fff, FP_SRC_EX(%a6) # set exp of SNAN
	bfextu		(%a0){&9:&23}, %d0
	lsl.l		&0x8, %d0		# extract and insert hi(man)
	mov.l		%d0, FP_SRC_HI(%a6)
	clr.l		FP_SRC_LO(%a6)

	btst		&0x7, (%a0)		# see if sign of SNAN is set
	beq.b		no_sgl_snan_sgn
	bset		&0x7, FP_SRC_EX(%a6)
no_sgl_snan_sgn:
	rts

#########################################
# load a DBL into %fp0:			#
# 	-number can't fault		#
#	(1) calc ea			#
#	(2) read 8 bytes into L_SCR(1,2)#
#	(3) fmov.d into %fp0		#
#########################################
load_dbl:
	movq.l		&0x8, %d0		# pass: 8 (bytes)
	bsr.l		_dcalc_ea		# calc <ea>; <ea> in %a0

	cmpi.b		SPCOND_FLG(%a6),&immed_flg
	beq.b		load_dbl_immed

	lea		L_SCR1(%a6), %a1	# pass: ptr to input dbl tmp space
	movq.l		&0x8, %d0		# pass: # bytes to read
	bsr.l		_dmem_read		# fetch src operand from memory

	tst.l		%d1			# did dfetch fail?
	bne.l		facc_in_d		# yes

load_dbl_cont:
	lea		L_SCR1(%a6), %a0	# pass: ptr to input dbl
	bsr.l		set_tag_d		# determine src type tag
	mov.b		%d0, STAG(%a6)		# set src optype tag

	cmpi.b		%d0, &DENORM		# is it a dbl DENORM?
	beq.w		get_dbl_denorm		# yes

	cmpi.b		%d0, &SNAN		# is it a dbl SNAN?
	beq.w		get_dbl_snan		# yes

	fmov.d		L_SCR1(%a6), %fp0	# read into %fp0;convert to xprec
	fmovm.x		&0x80, FP_SRC(%a6)	# return src op in FP_SRC
	rts

load_dbl_immed:
	lea		L_SCR1(%a6), %a1	# pass: ptr to input dbl tmp space
	movq.l		&0x8, %d0		# pass: # bytes to read
	bsr.l		_imem_read		# fetch src operand from memory

	tst.l		%d1			# did ifetch fail?
	bne.l		funimp_iacc		# yes
	bra.b		load_dbl_cont

# must convert dbl denorm format to an Xprec denorm fmt suitable for 
# normalization...
# %a0 : loc. of dbl denorm
get_dbl_denorm:
	clr.w		FP_SRC_EX(%a6)
	bfextu		(%a0){&12:&31}, %d0	# fetch hi(_mantissa)
	mov.l		%d0, FP_SRC_HI(%a6)
	bfextu		4(%a0){&11:&21}, %d0	# fetch lo(_mantissa)
	mov.l		&0xb, %d1
	lsl.l		%d1, %d0
	mov.l		%d0, FP_SRC_LO(%a6)

	btst		&0x7, (%a0)		# is sgn bit set?
	beq.b		dbl_dnrm_norm
	bset		&0x7, FP_SRC_EX(%a6)	# set sgn of xprec value

dbl_dnrm_norm:
	lea		FP_SRC(%a6), %a0
	bsr.l		norm			# normalize number
	mov.w		&0x3c01, %d1		# xprec exp = 0x3c01
	sub.w		%d0, %d1		# exp = 0x3c01 - shft amt.
	or.w		%d1, FP_SRC_EX(%a6)	# {sgn,exp}

	mov.b		&NORM, STAG(%a6)	# fix src type tag
	rts

# convert dbl to ext SNAN
# %a0 : points to dbl SNAN
get_dbl_snan:
	mov.w		&0x7fff, FP_SRC_EX(%a6) # set exp of SNAN

	bfextu		(%a0){&12:&31}, %d0	# fetch hi(_mantissa)
	mov.l		%d0, FP_SRC_HI(%a6)
	bfextu		4(%a0){&11:&21}, %d0	# fetch lo(_mantissa)
	mov.l		&0xb, %d1
	lsl.l		%d1, %d0
	mov.l		%d0, FP_SRC_LO(%a6)

	btst		&0x7, (%a0)		# see if sign of SNAN is set
	beq.b		no_dbl_snan_sgn
	bset		&0x7, FP_SRC_EX(%a6)
no_dbl_snan_sgn:
	rts

#################################################
# load a Xprec into %fp0:			#
# 	-number can't fault			#
#	(1) calc ea				#
#	(2) read 12 bytes into L_SCR(1,2)	#
#	(3) fmov.x into %fp0			#
#################################################
load_ext:
	mov.l		&0xc, %d0		# pass: 12 (bytes)
	bsr.l		_dcalc_ea		# calc <ea>

	lea		FP_SRC(%a6), %a1	# pass: ptr to input ext tmp space
	mov.l		&0xc, %d0		# pass: # of bytes to read
	bsr.l		_dmem_read		# fetch src operand from memory

	tst.l		%d1			# did dfetch fail?
	bne.l		facc_in_x		# yes

	lea		FP_SRC(%a6), %a0	# pass: ptr to src op
	bsr.l		set_tag_x		# determine src type tag

	cmpi.b		%d0, &UNNORM		# is the src op an UNNORM?
	beq.b		load_ext_unnorm		# yes

	mov.b		%d0, STAG(%a6)		# store the src optype tag
	rts

load_ext_unnorm:
	bsr.l		unnorm_fix		# fix the src UNNORM
	mov.b		%d0, STAG(%a6)		# store the src optype tag
	rts

#################################################
# load a packed into %fp0:			#
# 	-number can't fault			#
#	(1) calc ea				#
#	(2) read 12 bytes into L_SCR(1,2,3)	#
#	(3) fmov.x into %fp0			#
#################################################
load_packed:
	bsr.l		get_packed

	lea		FP_SRC(%a6),%a0		# pass ptr to src op
	bsr.l		set_tag_x		# determine src type tag
	cmpi.b		%d0,&UNNORM		# is the src op an UNNORM ZERO?
	beq.b		load_packed_unnorm	# yes

	mov.b		%d0,STAG(%a6)		# store the src optype tag
	rts

load_packed_unnorm:
	bsr.l		unnorm_fix		# fix the UNNORM ZERO
	mov.b		%d0,STAG(%a6)		# store the src optype tag
	rts	

#########################################################################
# XDEF ****************************************************************	#
# 	fout(): move from fp register to memory or data register	#
#									#
# XREF ****************************************************************	#
#	_round() - needed to create EXOP for sgl/dbl precision		#
#	norm() - needed to create EXOP for extended precision		#
#	ovf_res() - create default overflow result for sgl/dbl precision#
#	unf_res() - create default underflow result for sgl/dbl prec.	#
#	dst_dbl() - create rounded dbl precision result.		#
#	dst_sgl() - create rounded sgl precision result.		#
#	fetch_dreg() - fetch dynamic k-factor reg for packed.		#
#	bindec() - convert FP binary number to packed number.		#
#	_mem_write() - write data to memory.				#
#	_mem_write2() - write data to memory unless supv mode -(a7) exc.#
#	_dmem_write_{byte,word,long}() - write data to memory.		#
#	store_dreg_{b,w,l}() - store data to data register file.	#
#	facc_out_{b,w,l,d,x}() - data access error occurred.		#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision source operand		#
#	d0 = round prec,mode						#
# 									#
# OUTPUT **************************************************************	#
#	fp0 : intermediate underflow or overflow result if		#
#	      OVFL/UNFL occurred for a sgl or dbl operand		#
#									#
# ALGORITHM ***********************************************************	#
#	This routine is accessed by many handlers that need to do an	#
# opclass three move of an operand out to memory.			#
#	Decode an fmove out (opclass 3) instruction to determine if	#
# it's b,w,l,s,d,x, or p in size. b,w,l can be stored to either a data	#
# register or memory. The algorithm uses a standard "fmove" to create	#
# the rounded result. Also, since exceptions are disabled, this also	#
# create the correct OPERR default result if appropriate.		#
#	For sgl or dbl precision, overflow or underflow can occur. If	#
# either occurs and is enabled, the EXOP.				#
#	For extended precision, the stacked <ea> must be fixed along	#
# w/ the address index register as appropriate w/ _calc_ea_fout(). If	#
# the source is a denorm and if underflow is enabled, an EXOP must be	#
# created.								#
# 	For packed, the k-factor must be fetched from the instruction	#
# word or a data register. The <ea> must be fixed as w/ extended 	#
# precision. Then, bindec() is called to create the appropriate 	#
# packed result.							#
#	If at any time an access error is flagged by one of the move-	#
# to-memory routines, then a special exit must be made so that the	#
# access error can be handled properly.					#
#									#
#########################################################################

	global		fout
fout:
	bfextu		EXC_CMDREG(%a6){&3:&3},%d1 # extract dst fmt
	mov.w		(tbl_fout.b,%pc,%d1.w*2),%a1 # use as index
	jmp		(tbl_fout.b,%pc,%a1)	# jump to routine

	swbeg		&0x8
tbl_fout:
	short		fout_long	-	tbl_fout
	short		fout_sgl	-	tbl_fout
	short		fout_ext	-	tbl_fout
	short		fout_pack	-	tbl_fout
	short		fout_word	-	tbl_fout
	short		fout_dbl	-	tbl_fout
	short		fout_byte	-	tbl_fout
	short		fout_pack	-	tbl_fout

#################################################################
# fmove.b out ###################################################
#################################################################

# Only "Unimplemented Data Type" exceptions enter here. The operand
# is either a DENORM or a NORM.
fout_byte:
	tst.b		STAG(%a6)		# is operand normalized?
	bne.b		fout_byte_denorm	# no

	fmovm.x		SRC(%a0),&0x80		# load value

fout_byte_norm:
	fmov.l		%d0,%fpcr		# insert rnd prec,mode

	fmov.b		%fp0,%d0		# exec move out w/ correct rnd mode

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# fetch FPSR
	or.w		%d1,2+USER_FPSR(%a6)	# save new exc,accrued bits

	mov.b		1+EXC_OPWORD(%a6),%d1	# extract dst mode
	andi.b		&0x38,%d1		# is mode == 0? (Dreg dst)
	beq.b		fout_byte_dn		# must save to integer regfile

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	bsr.l		_dmem_write_byte	# write byte

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_b		# yes

	rts

fout_byte_dn:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract Dn
	andi.w		&0x7,%d1
	bsr.l		store_dreg_b
	rts

fout_byte_denorm:
	mov.l		SRC_EX(%a0),%d1
	andi.l		&0x80000000,%d1		# keep DENORM sign
	ori.l		&0x00800000,%d1		# make smallest sgl
	fmov.s		%d1,%fp0
	bra.b		fout_byte_norm

#################################################################
# fmove.w out ###################################################
#################################################################

# Only "Unimplemented Data Type" exceptions enter here. The operand
# is either a DENORM or a NORM.
fout_word:
	tst.b		STAG(%a6)		# is operand normalized?
	bne.b		fout_word_denorm	# no

	fmovm.x		SRC(%a0),&0x80		# load value

fout_word_norm:
	fmov.l		%d0,%fpcr		# insert rnd prec:mode

	fmov.w		%fp0,%d0		# exec move out w/ correct rnd mode

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# fetch FPSR
	or.w		%d1,2+USER_FPSR(%a6)	# save new exc,accrued bits

	mov.b		1+EXC_OPWORD(%a6),%d1	# extract dst mode
	andi.b		&0x38,%d1		# is mode == 0? (Dreg dst)
	beq.b		fout_word_dn		# must save to integer regfile

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	bsr.l		_dmem_write_word	# write word

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_w		# yes

	rts

fout_word_dn:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract Dn
	andi.w		&0x7,%d1
	bsr.l		store_dreg_w
	rts

fout_word_denorm:
	mov.l		SRC_EX(%a0),%d1
	andi.l		&0x80000000,%d1		# keep DENORM sign
	ori.l		&0x00800000,%d1		# make smallest sgl
	fmov.s		%d1,%fp0
	bra.b		fout_word_norm
	
#################################################################
# fmove.l out ###################################################
#################################################################

# Only "Unimplemented Data Type" exceptions enter here. The operand
# is either a DENORM or a NORM.
fout_long:
	tst.b		STAG(%a6)		# is operand normalized?
	bne.b		fout_long_denorm	# no

	fmovm.x		SRC(%a0),&0x80		# load value

fout_long_norm:
	fmov.l		%d0,%fpcr		# insert rnd prec:mode

	fmov.l		%fp0,%d0		# exec move out w/ correct rnd mode

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# fetch FPSR
	or.w		%d1,2+USER_FPSR(%a6)	# save new exc,accrued bits

fout_long_write:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract dst mode
	andi.b		&0x38,%d1		# is mode == 0? (Dreg dst)
	beq.b		fout_long_dn		# must save to integer regfile

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	bsr.l		_dmem_write_long	# write long

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_l		# yes

	rts

fout_long_dn:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract Dn
	andi.w		&0x7,%d1
	bsr.l		store_dreg_l
	rts

fout_long_denorm:
	mov.l		SRC_EX(%a0),%d1
	andi.l		&0x80000000,%d1		# keep DENORM sign
	ori.l		&0x00800000,%d1		# make smallest sgl
	fmov.s		%d1,%fp0
	bra.b		fout_long_norm

#################################################################
# fmove.x out ###################################################
#################################################################

# Only "Unimplemented Data Type" exceptions enter here. The operand
# is either a DENORM or a NORM.
# The DENORM causes an Underflow exception.
fout_ext:

# we copy the extended precision result to FP_SCR0 so that the reserved
# 16-bit field gets zeroed. we do this since we promise not to disturb
# what's at SRC(a0).
	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	clr.w		2+FP_SCR0_EX(%a6)	# clear reserved field
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	fmovm.x		SRC(%a0),&0x80		# return result

	bsr.l		_calc_ea_fout		# fix stacked <ea>

	mov.l		%a0,%a1			# pass: dst addr
	lea		FP_SCR0(%a6),%a0	# pass: src addr
	mov.l		&0xc,%d0		# pass: opsize is 12 bytes

# we must not yet write the extended precision data to the stack
# in the pre-decrement case from supervisor mode or else we'll corrupt 
# the stack frame. so, leave it in FP_SRC for now and deal with it later...
	cmpi.b		SPCOND_FLG(%a6),&mda7_flg
	beq.b		fout_ext_a7

	bsr.l		_dmem_write		# write ext prec number to memory

	tst.l		%d1			# did dstore fail?
	bne.w		fout_ext_err		# yes

	tst.b		STAG(%a6)		# is operand normalized?
	bne.b		fout_ext_denorm		# no
	rts

# the number is a DENORM. must set the underflow exception bit
fout_ext_denorm:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set underflow exc bit

	mov.b		FPCR_ENABLE(%a6),%d0
	andi.b		&0x0a,%d0		# is UNFL or INEX enabled?
	bne.b		fout_ext_exc		# yes
	rts

# we don't want to do the write if the exception occurred in supervisor mode
# so _mem_write2() handles this for us.
fout_ext_a7:
	bsr.l		_mem_write2		# write ext prec number to memory

	tst.l		%d1			# did dstore fail?
	bne.w		fout_ext_err		# yes

	tst.b		STAG(%a6)		# is operand normalized?
	bne.b		fout_ext_denorm		# no
	rts

fout_ext_exc:
	lea		FP_SCR0(%a6),%a0
	bsr.l		norm			# normalize the mantissa
	neg.w		%d0			# new exp = -(shft amt)
	andi.w		&0x7fff,%d0
	andi.w		&0x8000,FP_SCR0_EX(%a6)	# keep only old sign
	or.w		%d0,FP_SCR0_EX(%a6)	# insert new exponent
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	rts

fout_ext_err:
	mov.l		EXC_A6(%a6),(%a6)	# fix stacked a6
	bra.l		facc_out_x

#########################################################################
# fmove.s out ###########################################################
#########################################################################
fout_sgl:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&s_mode*0x10,%d0	# insert sgl prec
	mov.l		%d0,L_SCR3(%a6)		# save rnd prec,mode on stack

#
# operand is a normalized number. first, we check to see if the move out
# would cause either an underflow or overflow. these cases are handled
# separately. otherwise, set the FPCR to the proper rounding mode and
# execute the move.
#
	mov.w		SRC_EX(%a0),%d0		# extract exponent
	andi.w		&0x7fff,%d0		# strip sign

	cmpi.w		%d0,&SGL_HI		# will operand overflow?
	bgt.w		fout_sgl_ovfl		# yes; go handle OVFL
	beq.w		fout_sgl_may_ovfl	# maybe; go handle possible OVFL
	cmpi.w		%d0,&SGL_LO		# will operand underflow?
	blt.w		fout_sgl_unfl		# yes; go handle underflow

#
# NORMs(in range) can be stored out by a simple "fmov.s"
# Unnormalized inputs can come through this point.
#
fout_sgl_exg:
	fmovm.x		SRC(%a0),&0x80		# fetch fop from stack

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmov.s		%fp0,%d0		# store does convert and round

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d1		# save FPSR

	or.w		%d1,2+USER_FPSR(%a6) 	# set possible inex2/ainex

fout_sgl_exg_write:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract dst mode
	andi.b		&0x38,%d1		# is mode == 0? (Dreg dst)
	beq.b		fout_sgl_exg_write_dn	# must save to integer regfile

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	bsr.l		_dmem_write_long	# write long

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_l		# yes

	rts

fout_sgl_exg_write_dn:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract Dn
	andi.w		&0x7,%d1
	bsr.l		store_dreg_l
	rts

#
# here, we know that the operand would UNFL if moved out to single prec,
# so, denorm and round and then use generic store single routine to
# write the value to memory.
#
fout_sgl_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set UNFL

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	mov.l		%a0,-(%sp)

	clr.l		%d0			# pass: S.F. = 0

	cmpi.b		STAG(%a6),&DENORM	# fetch src optype tag
	bne.b		fout_sgl_unfl_cont	# let DENORMs fall through

	lea		FP_SCR0(%a6),%a0
	bsr.l		norm			# normalize the DENORM
	
fout_sgl_unfl_cont:
	lea		FP_SCR0(%a6),%a0	# pass: ptr to operand
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calc default underflow result

	lea		FP_SCR0(%a6),%a0	# pass: ptr to fop
	bsr.l		dst_sgl			# convert to single prec

	mov.b		1+EXC_OPWORD(%a6),%d1	# extract dst mode
	andi.b		&0x38,%d1		# is mode == 0? (Dreg dst)
	beq.b		fout_sgl_unfl_dn	# must save to integer regfile

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	bsr.l		_dmem_write_long	# write long

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_l		# yes

	bra.b		fout_sgl_unfl_chkexc

fout_sgl_unfl_dn:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract Dn
	andi.w		&0x7,%d1
	bsr.l		store_dreg_l

fout_sgl_unfl_chkexc:
	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0a,%d1		# is UNFL or INEX enabled?
	bne.w		fout_sd_exc_unfl	# yes
	addq.l		&0x4,%sp
	rts

#
# it's definitely an overflow so call ovf_res to get the correct answer
#
fout_sgl_ovfl:
	tst.b		3+SRC_HI(%a0)		# is result inexact?
	bne.b		fout_sgl_ovfl_inex2
	tst.l		SRC_LO(%a0)		# is result inexact?
	bne.b		fout_sgl_ovfl_inex2
	ori.w		&ovfl_inx_mask,2+USER_FPSR(%a6) # set ovfl/aovfl/ainex
	bra.b		fout_sgl_ovfl_cont
fout_sgl_ovfl_inex2:
	ori.w		&ovfinx_mask,2+USER_FPSR(%a6) # set ovfl/aovfl/ainex/inex2

fout_sgl_ovfl_cont:
	mov.l		%a0,-(%sp)

# call ovf_res() w/ sgl prec and the correct rnd mode to create the default
# overflow result. DON'T save the returned ccodes from ovf_res() since
# fmove out doesn't alter them. 
	tst.b		SRC_EX(%a0)		# is operand negative?
	smi		%d1			# set if so
	mov.l		L_SCR3(%a6),%d0		# pass: sgl prec,rnd mode
	bsr.l		ovf_res			# calc OVFL result
	fmovm.x		(%a0),&0x80		# load default overflow result
	fmov.s		%fp0,%d0		# store to single

	mov.b		1+EXC_OPWORD(%a6),%d1	# extract dst mode
	andi.b		&0x38,%d1		# is mode == 0? (Dreg dst)
	beq.b		fout_sgl_ovfl_dn	# must save to integer regfile

	mov.l		EXC_EA(%a6),%a0		# stacked <ea> is correct
	bsr.l		_dmem_write_long	# write long

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_l		# yes

	bra.b		fout_sgl_ovfl_chkexc

fout_sgl_ovfl_dn:
	mov.b		1+EXC_OPWORD(%a6),%d1	# extract Dn
	andi.w		&0x7,%d1
	bsr.l		store_dreg_l

fout_sgl_ovfl_chkexc:
	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0a,%d1		# is UNFL or INEX enabled?
	bne.w		fout_sd_exc_ovfl	# yes
	addq.l		&0x4,%sp
	rts

#
# move out MAY overflow:
# (1) force the exp to 0x3fff
# (2) do a move w/ appropriate rnd mode
# (3) if exp still equals zero, then insert original exponent
#	for the correct result.
#     if exp now equals one, then it overflowed so call ovf_res.
#
fout_sgl_may_ovfl:
	mov.w		SRC_EX(%a0),%d1		# fetch current sign
	andi.w		&0x8000,%d1		# keep it,clear exp
	ori.w		&0x3fff,%d1		# insert exp = 0
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert scaled exp
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6) # copy hi(man)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6) # copy lo(man)

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fmov.x		FP_SCR0(%a6),%fp0	# force fop to be rounded
	fmov.l		&0x0,%fpcr		# clear FPCR

	fabs.x		%fp0			# need absolute value
	fcmp.b		%fp0,&0x2		# did exponent increase?
	fblt.w		fout_sgl_exg		# no; go finish NORM	
	bra.w		fout_sgl_ovfl		# yes; go handle overflow

################

fout_sd_exc_unfl:
	mov.l		(%sp)+,%a0

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

	cmpi.b		STAG(%a6),&DENORM	# was src a DENORM?
	bne.b		fout_sd_exc_cont	# no

	lea		FP_SCR0(%a6),%a0
	bsr.l		norm
	neg.l		%d0
	andi.w		&0x7fff,%d0
	bfins		%d0,FP_SCR0_EX(%a6){&1:&15}
	bra.b		fout_sd_exc_cont

fout_sd_exc:
fout_sd_exc_ovfl:
	mov.l		(%sp)+,%a0		# restore a0

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)

fout_sd_exc_cont:
	bclr		&0x7,FP_SCR0_EX(%a6)	# clear sign bit
	sne.b		2+FP_SCR0_EX(%a6)	# set internal sign bit
	lea		FP_SCR0(%a6),%a0	# pass: ptr to DENORM

	mov.b		3+L_SCR3(%a6),%d1
	lsr.b		&0x4,%d1
	andi.w		&0x0c,%d1
	swap		%d1
	mov.b		3+L_SCR3(%a6),%d1
	lsr.b		&0x4,%d1
	andi.w		&0x03,%d1
	clr.l		%d0			# pass: zero g,r,s
	bsr.l		_round			# round the DENORM

	tst.b		2+FP_SCR0_EX(%a6)	# is EXOP negative?
	beq.b		fout_sd_exc_done	# no
	bset		&0x7,FP_SCR0_EX(%a6)	# yes

fout_sd_exc_done:
	fmovm.x		FP_SCR0(%a6),&0x40	# return EXOP in fp1
	rts

#################################################################
# fmove.d out ###################################################
#################################################################
fout_dbl:
	andi.b		&0x30,%d0		# clear rnd prec
	ori.b		&d_mode*0x10,%d0	# insert dbl prec
	mov.l		%d0,L_SCR3(%a6)		# save rnd prec,mode on stack

#
# operand is a normalized number. first, we check to see if the move out
# would cause either an underflow or overflow. these cases are handled
# separately. otherwise, set the FPCR to the proper rounding mode and
# execute the move.
#
	mov.w		SRC_EX(%a0),%d0		# extract exponent
	andi.w		&0x7fff,%d0		# strip sign

	cmpi.w		%d0,&DBL_HI		# will operand overflow?
	bgt.w		fout_dbl_ovfl		# yes; go handle OVFL
	beq.w		fout_dbl_may_ovfl	# maybe; go handle possible OVFL
	cmpi.w		%d0,&DBL_LO		# will operand underflow?
	blt.w		fout_dbl_unfl		# yes; go handle underflow

#
# NORMs(in range) can be stored out by a simple "fmov.d"
# Unnormalized inputs can come through this point.
#
fout_dbl_exg:
	fmovm.x		SRC(%a0),&0x80		# fetch fop from stack

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR
	fmov.l		&0x0,%fpsr		# clear FPSR

	fmov.d		%fp0,L_SCR1(%a6)	# store does convert and round

	fmov.l		&0x0,%fpcr		# clear FPCR
	fmov.l		%fpsr,%d0		# save FPSR

	or.w		%d0,2+USER_FPSR(%a6) 	# set possible inex2/ainex

	mov.l		EXC_EA(%a6),%a1		# pass: dst addr
	lea		L_SCR1(%a6),%a0		# pass: src addr
	movq.l		&0x8,%d0		# pass: opsize is 8 bytes
	bsr.l		_dmem_write		# store dbl fop to memory

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_d		# yes

	rts					# no; so we're finished	

#
# here, we know that the operand would UNFL if moved out to double prec,
# so, denorm and round and then use generic store double routine to
# write the value to memory.
#
fout_dbl_unfl:
	bset		&unfl_bit,FPSR_EXCEPT(%a6) # set UNFL

	mov.w		SRC_EX(%a0),FP_SCR0_EX(%a6)
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6)
	mov.l		%a0,-(%sp)

	clr.l		%d0			# pass: S.F. = 0

	cmpi.b		STAG(%a6),&DENORM	# fetch src optype tag
	bne.b		fout_dbl_unfl_cont	# let DENORMs fall through

	lea		FP_SCR0(%a6),%a0
	bsr.l		norm			# normalize the DENORM
	
fout_dbl_unfl_cont:
	lea		FP_SCR0(%a6),%a0	# pass: ptr to operand
	mov.l		L_SCR3(%a6),%d1		# pass: rnd prec,mode
	bsr.l		unf_res			# calc default underflow result

	lea		FP_SCR0(%a6),%a0	# pass: ptr to fop
	bsr.l		dst_dbl			# convert to single prec
	mov.l		%d0,L_SCR1(%a6)
	mov.l		%d1,L_SCR2(%a6)

	mov.l		EXC_EA(%a6),%a1		# pass: dst addr
	lea		L_SCR1(%a6),%a0		# pass: src addr
	movq.l		&0x8,%d0		# pass: opsize is 8 bytes
	bsr.l		_dmem_write		# store dbl fop to memory

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_d		# yes

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0a,%d1		# is UNFL or INEX enabled?
	bne.w		fout_sd_exc_unfl	# yes
	addq.l		&0x4,%sp
	rts

#
# it's definitely an overflow so call ovf_res to get the correct answer
#
fout_dbl_ovfl:
	mov.w		2+SRC_LO(%a0),%d0
	andi.w		&0x7ff,%d0
	bne.b		fout_dbl_ovfl_inex2

	ori.w		&ovfl_inx_mask,2+USER_FPSR(%a6) # set ovfl/aovfl/ainex
	bra.b		fout_dbl_ovfl_cont
fout_dbl_ovfl_inex2:
	ori.w		&ovfinx_mask,2+USER_FPSR(%a6) # set ovfl/aovfl/ainex/inex2

fout_dbl_ovfl_cont:
	mov.l		%a0,-(%sp)

# call ovf_res() w/ dbl prec and the correct rnd mode to create the default
# overflow result. DON'T save the returned ccodes from ovf_res() since
# fmove out doesn't alter them. 
	tst.b		SRC_EX(%a0)		# is operand negative?
	smi		%d1			# set if so
	mov.l		L_SCR3(%a6),%d0		# pass: dbl prec,rnd mode
	bsr.l		ovf_res			# calc OVFL result
	fmovm.x		(%a0),&0x80		# load default overflow result
	fmov.d		%fp0,L_SCR1(%a6)	# store to double

	mov.l		EXC_EA(%a6),%a1		# pass: dst addr
	lea		L_SCR1(%a6),%a0		# pass: src addr
	movq.l		&0x8,%d0		# pass: opsize is 8 bytes
	bsr.l		_dmem_write		# store dbl fop to memory

	tst.l		%d1			# did dstore fail?
	bne.l		facc_out_d		# yes

	mov.b		FPCR_ENABLE(%a6),%d1
	andi.b		&0x0a,%d1		# is UNFL or INEX enabled?
	bne.w		fout_sd_exc_ovfl	# yes
	addq.l		&0x4,%sp
	rts

#
# move out MAY overflow:
# (1) force the exp to 0x3fff
# (2) do a move w/ appropriate rnd mode
# (3) if exp still equals zero, then insert original exponent
#	for the correct result.
#     if exp now equals one, then it overflowed so call ovf_res.
#
fout_dbl_may_ovfl:
	mov.w		SRC_EX(%a0),%d1		# fetch current sign
	andi.w		&0x8000,%d1		# keep it,clear exp
	ori.w		&0x3fff,%d1		# insert exp = 0
	mov.w		%d1,FP_SCR0_EX(%a6)	# insert scaled exp
	mov.l		SRC_HI(%a0),FP_SCR0_HI(%a6) # copy hi(man)
	mov.l		SRC_LO(%a0),FP_SCR0_LO(%a6) # copy lo(man)

	fmov.l		L_SCR3(%a6),%fpcr	# set FPCR

	fmov.x		FP_SCR0(%a6),%fp0	# force fop to be rounded
	fmov.l		&0x0,%fpcr		# clear FPCR

	fabs.x		%fp0			# need absolute value
	fcmp.b		%fp0,&0x2		# did exponent increase?
	fblt.w		fout_dbl_exg		# no; go finish NORM	
	bra.w		fout_dbl_ovfl		# yes; go handle overflow

#########################################################################
# XDEF ****************************************************************	#
# 	dst_dbl(): create double precision value from extended prec.	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to source operand in extended precision		#
# 									#
# OUTPUT **************************************************************	#
#	d0 = hi(double precision result)				#
#	d1 = lo(double precision result)				#
#									#
# ALGORITHM ***********************************************************	#
#									#
#  Changes extended precision to double precision.			#
#  Note: no attempt is made to round the extended value to double.	#
#	dbl_sign = ext_sign						#
#	dbl_exp = ext_exp - $3fff(ext bias) + $7ff(dbl bias)		#
#	get rid of ext integer bit					#
#	dbl_mant = ext_mant{62:12}					#
#									#
#	    	---------------   ---------------    ---------------	#
#  extended ->  |s|    exp    |   |1| ms mant   |    | ls mant     |	#
#	    	---------------   ---------------    ---------------	#
#	   	 95	    64    63 62	      32      31     11	  0	#
#				     |			     |		#
#				     |			     |		#
#				     |			     |		#
#		 	             v   		     v		#
#	    		      ---------------   ---------------		#
#  double   ->  	      |s|exp| mant  |   |  mant       |		#
#	    		      ---------------   ---------------		#
#	   	 	      63     51   32   31	       0	#
#									#
#########################################################################

dst_dbl:
	clr.l		%d0			# clear d0
	mov.w		FTEMP_EX(%a0),%d0	# get exponent
	subi.w		&EXT_BIAS,%d0		# subtract extended precision bias
	addi.w		&DBL_BIAS,%d0		# add double precision bias
	tst.b		FTEMP_HI(%a0)		# is number a denorm?
	bmi.b		dst_get_dupper		# no
	subq.w		&0x1,%d0		# yes; denorm bias = DBL_BIAS - 1
dst_get_dupper:
	swap		%d0			# d0 now in upper word
	lsl.l		&0x4,%d0		# d0 in proper place for dbl prec exp
	tst.b		FTEMP_EX(%a0)		# test sign
	bpl.b		dst_get_dman		# if postive, go process mantissa
	bset		&0x1f,%d0		# if negative, set sign
dst_get_dman:
	mov.l		FTEMP_HI(%a0),%d1	# get ms mantissa
	bfextu		%d1{&1:&20},%d1		# get upper 20 bits of ms
	or.l		%d1,%d0			# put these bits in ms word of double
	mov.l		%d0,L_SCR1(%a6)		# put the new exp back on the stack
	mov.l		FTEMP_HI(%a0),%d1	# get ms mantissa
	mov.l		&21,%d0			# load shift count
	lsl.l		%d0,%d1			# put lower 11 bits in upper bits
	mov.l		%d1,L_SCR2(%a6)		# build lower lword in memory
	mov.l		FTEMP_LO(%a0),%d1	# get ls mantissa
	bfextu		%d1{&0:&21},%d0		# get ls 21 bits of double
	mov.l		L_SCR2(%a6),%d1
	or.l		%d0,%d1			# put them in double result
	mov.l		L_SCR1(%a6),%d0
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	dst_sgl(): create single precision value from extended prec	#
#									#
# XREF ****************************************************************	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to source operand in extended precision		#
# 									#
# OUTPUT **************************************************************	#
#	d0 = single precision result					#
#									#
# ALGORITHM ***********************************************************	#
#									#
# Changes extended precision to single precision.			#
#	sgl_sign = ext_sign						#
#	sgl_exp = ext_exp - $3fff(ext bias) + $7f(sgl bias)		#
#	get rid of ext integer bit					#
#	sgl_mant = ext_mant{62:12}					#
#									#
#	    	---------------   ---------------    ---------------	#
#  extended ->  |s|    exp    |   |1| ms mant   |    | ls mant     |	#
#	    	---------------   ---------------    ---------------	#
#	   	 95	    64    63 62	   40 32      31     12	  0	#
#				     |	   |				#
#				     |	   |				#
#				     |	   |				#
#		 	             v     v				#
#	    		      ---------------				#
#  single   ->  	      |s|exp| mant  |				#
#	    		      ---------------				#
#	   	 	      31     22     0				#
#									#
#########################################################################

dst_sgl:
	clr.l		%d0
	mov.w		FTEMP_EX(%a0),%d0	# get exponent
	subi.w		&EXT_BIAS,%d0		# subtract extended precision bias
	addi.w		&SGL_BIAS,%d0		# add single precision bias
	tst.b		FTEMP_HI(%a0)		# is number a denorm?
	bmi.b		dst_get_supper		# no
	subq.w		&0x1,%d0		# yes; denorm bias = SGL_BIAS - 1
dst_get_supper:
	swap		%d0			# put exp in upper word of d0
	lsl.l		&0x7,%d0		# shift it into single exp bits
	tst.b		FTEMP_EX(%a0)		# test sign
	bpl.b		dst_get_sman		# if positive, continue
	bset		&0x1f,%d0		# if negative, put in sign first
dst_get_sman:
	mov.l		FTEMP_HI(%a0),%d1	# get ms mantissa
	andi.l		&0x7fffff00,%d1		# get upper 23 bits of ms
	lsr.l		&0x8,%d1		# and put them flush right
	or.l		%d1,%d0			# put these bits in ms word of single
	rts

##############################################################################
fout_pack:
	bsr.l		_calc_ea_fout		# fetch the <ea>
	mov.l		%a0,-(%sp)

	mov.b		STAG(%a6),%d0		# fetch input type
	bne.w		fout_pack_not_norm	# input is not NORM

fout_pack_norm:
	btst		&0x4,EXC_CMDREG(%a6)	# static or dynamic?
	beq.b		fout_pack_s		# static

fout_pack_d:
	mov.b		1+EXC_CMDREG(%a6),%d1	# fetch dynamic reg
	lsr.b		&0x4,%d1
	andi.w		&0x7,%d1

	bsr.l		fetch_dreg		# fetch Dn w/ k-factor

	bra.b		fout_pack_type
fout_pack_s:
	mov.b		1+EXC_CMDREG(%a6),%d0	# fetch static field

fout_pack_type:
	bfexts		%d0{&25:&7},%d0		# extract k-factor
	mov.l	%d0,-(%sp)

	lea		FP_SRC(%a6),%a0		# pass: ptr to input

# bindec is currently scrambling FP_SRC for denorm inputs.
# we'll have to change this, but for now, tough luck!!!
	bsr.l		bindec			# convert xprec to packed

#	andi.l		&0xcfff000f,FP_SCR0(%a6) # clear unused fields
	andi.l		&0xcffff00f,FP_SCR0(%a6) # clear unused fields

	mov.l	(%sp)+,%d0

	tst.b		3+FP_SCR0_EX(%a6)
	bne.b		fout_pack_set
	tst.l		FP_SCR0_HI(%a6)
	bne.b		fout_pack_set
	tst.l		FP_SCR0_LO(%a6)
	bne.b		fout_pack_set

# add the extra condition that only if the k-factor was zero, too, should
# we zero the exponent
	tst.l		%d0
	bne.b		fout_pack_set	
# "mantissa" is all zero which means that the answer is zero. but, the '040
# algorithm allows the exponent to be non-zero. the 881/2 do not. therefore,
# if the mantissa is zero, I will zero the exponent, too.
# the question now is whether the exponents sign bit is allowed to be non-zero
# for a zero, also...
	andi.w		&0xf000,FP_SCR0(%a6)

fout_pack_set:

	lea		FP_SCR0(%a6),%a0	# pass: src addr

fout_pack_write:
	mov.l		(%sp)+,%a1		# pass: dst addr
	mov.l		&0xc,%d0		# pass: opsize is 12 bytes

	cmpi.b		SPCOND_FLG(%a6),&mda7_flg
	beq.b		fout_pack_a7

	bsr.l		_dmem_write		# write ext prec number to memory

	tst.l		%d1			# did dstore fail?
	bne.w		fout_ext_err		# yes

	rts

# we don't want to do the write if the exception occurred in supervisor mode
# so _mem_write2() handles this for us.
fout_pack_a7:
	bsr.l		_mem_write2		# write ext prec number to memory

	tst.l		%d1			# did dstore fail?
	bne.w		fout_ext_err		# yes

	rts

fout_pack_not_norm:
	cmpi.b		%d0,&DENORM		# is it a DENORM?
	beq.w		fout_pack_norm		# yes
	lea		FP_SRC(%a6),%a0
	clr.w		2+FP_SRC_EX(%a6)
	cmpi.b		%d0,&SNAN		# is it an SNAN?
	beq.b		fout_pack_snan		# yes
	bra.b		fout_pack_write		# no

fout_pack_snan:
	ori.w		&snaniop2_mask,FPSR_EXCEPT(%a6) # set SNAN/AIOP
	bset		&0x6,FP_SRC_HI(%a6)	# set snan bit
	bra.b		fout_pack_write

#########################################################################
# XDEF ****************************************************************	#
#	fetch_dreg(): fetch register according to index in d1		#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d1 = index of register to fetch from				#
# 									#
# OUTPUT **************************************************************	#
#	d0 = value of register fetched					#
#									#
# ALGORITHM ***********************************************************	#
#	According to the index value in d1 which can range from zero 	#
# to fifteen, load the corresponding register file value (where 	#
# address register indexes start at 8). D0/D1/A0/A1/A6/A7 are on the	#
# stack. The rest should still be in their original places.		#
#									#
#########################################################################

# this routine leaves d1 intact for subsequent store_dreg calls.
	global		fetch_dreg
fetch_dreg:
	mov.w		(tbl_fdreg.b,%pc,%d1.w*2),%d0
	jmp		(tbl_fdreg.b,%pc,%d0.w*1)

tbl_fdreg:
	short		fdreg0 - tbl_fdreg
	short		fdreg1 - tbl_fdreg
	short		fdreg2 - tbl_fdreg
	short		fdreg3 - tbl_fdreg
	short		fdreg4 - tbl_fdreg
	short		fdreg5 - tbl_fdreg
	short		fdreg6 - tbl_fdreg
	short		fdreg7 - tbl_fdreg
	short		fdreg8 - tbl_fdreg
	short		fdreg9 - tbl_fdreg
	short		fdrega - tbl_fdreg
	short		fdregb - tbl_fdreg
	short		fdregc - tbl_fdreg
	short		fdregd - tbl_fdreg
	short		fdrege - tbl_fdreg
	short		fdregf - tbl_fdreg

fdreg0:
	mov.l		EXC_DREGS+0x0(%a6),%d0
	rts
fdreg1:
	mov.l		EXC_DREGS+0x4(%a6),%d0
	rts
fdreg2:
	mov.l		%d2,%d0
	rts
fdreg3:
	mov.l		%d3,%d0
	rts
fdreg4:
	mov.l		%d4,%d0
	rts
fdreg5:
	mov.l		%d5,%d0
	rts
fdreg6:
	mov.l		%d6,%d0
	rts
fdreg7:
	mov.l		%d7,%d0
	rts
fdreg8:
	mov.l		EXC_DREGS+0x8(%a6),%d0
	rts
fdreg9:
	mov.l		EXC_DREGS+0xc(%a6),%d0
	rts
fdrega:
	mov.l		%a2,%d0
	rts
fdregb:
	mov.l		%a3,%d0
	rts
fdregc:
	mov.l		%a4,%d0
	rts
fdregd:
	mov.l		%a5,%d0
	rts
fdrege:
	mov.l		(%a6),%d0
	rts
fdregf:
	mov.l		EXC_A7(%a6),%d0
	rts

#########################################################################
# XDEF ****************************************************************	#
#	store_dreg_l(): store longword to data register specified by d1	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d0 = longowrd value to store					#
#	d1 = index of register to fetch from				#
# 									#
# OUTPUT **************************************************************	#
#	(data register is updated)					#
#									#
# ALGORITHM ***********************************************************	#
#	According to the index value in d1, store the longword value	#
# in d0 to the corresponding data register. D0/D1 are on the stack	#
# while the rest are in their initial places.				#
#									#
#########################################################################

	global		store_dreg_l
store_dreg_l:
	mov.w		(tbl_sdregl.b,%pc,%d1.w*2),%d1
	jmp		(tbl_sdregl.b,%pc,%d1.w*1)

tbl_sdregl:
	short		sdregl0 - tbl_sdregl
	short		sdregl1 - tbl_sdregl
	short		sdregl2 - tbl_sdregl
	short		sdregl3 - tbl_sdregl
	short		sdregl4 - tbl_sdregl
	short		sdregl5 - tbl_sdregl
	short		sdregl6 - tbl_sdregl
	short		sdregl7 - tbl_sdregl

sdregl0:
	mov.l		%d0,EXC_DREGS+0x0(%a6)
	rts
sdregl1:
	mov.l		%d0,EXC_DREGS+0x4(%a6)
	rts
sdregl2:
	mov.l		%d0,%d2
	rts
sdregl3:
	mov.l		%d0,%d3
	rts
sdregl4:
	mov.l		%d0,%d4
	rts
sdregl5:
	mov.l		%d0,%d5
	rts
sdregl6:
	mov.l		%d0,%d6
	rts
sdregl7:
	mov.l		%d0,%d7
	rts

#########################################################################
# XDEF ****************************************************************	#
#	store_dreg_w(): store word to data register specified by d1	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d0 = word value to store					#
#	d1 = index of register to fetch from				#
# 									#
# OUTPUT **************************************************************	#
#	(data register is updated)					#
#									#
# ALGORITHM ***********************************************************	#
#	According to the index value in d1, store the word value	#
# in d0 to the corresponding data register. D0/D1 are on the stack	#
# while the rest are in their initial places.				#
#									#
#########################################################################

	global		store_dreg_w
store_dreg_w:
	mov.w		(tbl_sdregw.b,%pc,%d1.w*2),%d1
	jmp		(tbl_sdregw.b,%pc,%d1.w*1)

tbl_sdregw:
	short		sdregw0 - tbl_sdregw
	short		sdregw1 - tbl_sdregw
	short		sdregw2 - tbl_sdregw
	short		sdregw3 - tbl_sdregw
	short		sdregw4 - tbl_sdregw
	short		sdregw5 - tbl_sdregw
	short		sdregw6 - tbl_sdregw
	short		sdregw7 - tbl_sdregw

sdregw0:
	mov.w		%d0,2+EXC_DREGS+0x0(%a6)
	rts
sdregw1:
	mov.w		%d0,2+EXC_DREGS+0x4(%a6)
	rts
sdregw2:
	mov.w		%d0,%d2
	rts
sdregw3:
	mov.w		%d0,%d3
	rts
sdregw4:
	mov.w		%d0,%d4
	rts
sdregw5:
	mov.w		%d0,%d5
	rts
sdregw6:
	mov.w		%d0,%d6
	rts
sdregw7:
	mov.w		%d0,%d7
	rts

#########################################################################
# XDEF ****************************************************************	#
#	store_dreg_b(): store byte to data register specified by d1	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d0 = byte value to store					#
#	d1 = index of register to fetch from				#
# 									#
# OUTPUT **************************************************************	#
#	(data register is updated)					#
#									#
# ALGORITHM ***********************************************************	#
#	According to the index value in d1, store the byte value	#
# in d0 to the corresponding data register. D0/D1 are on the stack	#
# while the rest are in their initial places.				#
#									#
#########################################################################

	global		store_dreg_b
store_dreg_b:
	mov.w		(tbl_sdregb.b,%pc,%d1.w*2),%d1
	jmp		(tbl_sdregb.b,%pc,%d1.w*1)

tbl_sdregb:
	short		sdregb0 - tbl_sdregb
	short		sdregb1 - tbl_sdregb
	short		sdregb2 - tbl_sdregb
	short		sdregb3 - tbl_sdregb
	short		sdregb4 - tbl_sdregb
	short		sdregb5 - tbl_sdregb
	short		sdregb6 - tbl_sdregb
	short		sdregb7 - tbl_sdregb

sdregb0:
	mov.b		%d0,3+EXC_DREGS+0x0(%a6)
	rts
sdregb1:
	mov.b		%d0,3+EXC_DREGS+0x4(%a6)
	rts
sdregb2:
	mov.b		%d0,%d2
	rts
sdregb3:
	mov.b		%d0,%d3
	rts
sdregb4:
	mov.b		%d0,%d4
	rts
sdregb5:
	mov.b		%d0,%d5
	rts
sdregb6:
	mov.b		%d0,%d6
	rts
sdregb7:
	mov.b		%d0,%d7
	rts

#########################################################################
# XDEF ****************************************************************	#
#	inc_areg(): increment an address register by the value in d0	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d0 = amount to increment by					#
#	d1 = index of address register to increment			#
# 									#
# OUTPUT **************************************************************	#
#	(address register is updated)					#
#									#
# ALGORITHM ***********************************************************	#
# 	Typically used for an instruction w/ a post-increment <ea>, 	#
# this routine adds the increment value in d0 to the address register	#
# specified by d1. A0/A1/A6/A7 reside on the stack. The rest reside	#
# in their original places.						#
# 	For a7, if the increment amount is one, then we have to 	#
# increment by two. For any a7 update, set the mia7_flag so that if	#
# an access error exception occurs later in emulation, this address	#
# register update can be undone.					#
#									#
#########################################################################

	global		inc_areg
inc_areg:
	mov.w		(tbl_iareg.b,%pc,%d1.w*2),%d1
	jmp		(tbl_iareg.b,%pc,%d1.w*1)

tbl_iareg:
	short		iareg0 - tbl_iareg
	short		iareg1 - tbl_iareg
	short		iareg2 - tbl_iareg
	short		iareg3 - tbl_iareg
	short		iareg4 - tbl_iareg
	short		iareg5 - tbl_iareg
	short		iareg6 - tbl_iareg
	short		iareg7 - tbl_iareg

iareg0:	add.l		%d0,EXC_DREGS+0x8(%a6)
	rts
iareg1:	add.l		%d0,EXC_DREGS+0xc(%a6)
	rts
iareg2:	add.l		%d0,%a2
	rts
iareg3:	add.l		%d0,%a3
	rts
iareg4:	add.l		%d0,%a4
	rts
iareg5:	add.l		%d0,%a5
	rts
iareg6:	add.l		%d0,(%a6)
	rts
iareg7:	mov.b		&mia7_flg,SPCOND_FLG(%a6)
	cmpi.b		%d0,&0x1
	beq.b		iareg7b
	add.l		%d0,EXC_A7(%a6)
	rts
iareg7b:
	addq.l		&0x2,EXC_A7(%a6)
	rts

#########################################################################
# XDEF ****************************************************************	#
#	dec_areg(): decrement an address register by the value in d0	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d0 = amount to decrement by					#
#	d1 = index of address register to decrement			#
# 									#
# OUTPUT **************************************************************	#
#	(address register is updated)					#
#									#
# ALGORITHM ***********************************************************	#
# 	Typically used for an instruction w/ a pre-decrement <ea>, 	#
# this routine adds the decrement value in d0 to the address register	#
# specified by d1. A0/A1/A6/A7 reside on the stack. The rest reside	#
# in their original places.						#
# 	For a7, if the decrement amount is one, then we have to 	#
# decrement by two. For any a7 update, set the mda7_flag so that if	#
# an access error exception occurs later in emulation, this address	#
# register update can be undone.					#
#									#
#########################################################################

	global		dec_areg
dec_areg:
	mov.w		(tbl_dareg.b,%pc,%d1.w*2),%d1
	jmp		(tbl_dareg.b,%pc,%d1.w*1)

tbl_dareg:
	short		dareg0 - tbl_dareg
	short		dareg1 - tbl_dareg
	short		dareg2 - tbl_dareg
	short		dareg3 - tbl_dareg
	short		dareg4 - tbl_dareg
	short		dareg5 - tbl_dareg
	short		dareg6 - tbl_dareg
	short		dareg7 - tbl_dareg

dareg0:	sub.l		%d0,EXC_DREGS+0x8(%a6)
	rts
dareg1:	sub.l		%d0,EXC_DREGS+0xc(%a6)
	rts
dareg2:	sub.l		%d0,%a2
	rts
dareg3:	sub.l		%d0,%a3
	rts
dareg4:	sub.l		%d0,%a4
	rts
dareg5:	sub.l		%d0,%a5
	rts
dareg6:	sub.l		%d0,(%a6)
	rts
dareg7:	mov.b		&mda7_flg,SPCOND_FLG(%a6)
	cmpi.b		%d0,&0x1
	beq.b		dareg7b
	sub.l		%d0,EXC_A7(%a6)
	rts
dareg7b:
	subq.l		&0x2,EXC_A7(%a6)
	rts

##############################################################################

#########################################################################
# XDEF ****************************************************************	#
#	load_fpn1(): load FP register value into FP_SRC(a6).		#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d0 = index of FP register to load				#
# 									#
# OUTPUT **************************************************************	#
#	FP_SRC(a6) = value loaded from FP register file			#
#									#
# ALGORITHM ***********************************************************	#
#	Using the index in d0, load FP_SRC(a6) with a number from the 	#
# FP register file.							#
#									#
#########################################################################

	global 		load_fpn1
load_fpn1:
	mov.w		(tbl_load_fpn1.b,%pc,%d0.w*2), %d0
	jmp		(tbl_load_fpn1.b,%pc,%d0.w*1)

tbl_load_fpn1:
	short		load_fpn1_0 - tbl_load_fpn1
	short		load_fpn1_1 - tbl_load_fpn1
	short		load_fpn1_2 - tbl_load_fpn1
	short		load_fpn1_3 - tbl_load_fpn1
	short		load_fpn1_4 - tbl_load_fpn1
	short		load_fpn1_5 - tbl_load_fpn1
	short		load_fpn1_6 - tbl_load_fpn1
	short		load_fpn1_7 - tbl_load_fpn1

load_fpn1_0:
	mov.l		0+EXC_FP0(%a6), 0+FP_SRC(%a6)
	mov.l		4+EXC_FP0(%a6), 4+FP_SRC(%a6)
	mov.l		8+EXC_FP0(%a6), 8+FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts
load_fpn1_1:
	mov.l		0+EXC_FP1(%a6), 0+FP_SRC(%a6)
	mov.l		4+EXC_FP1(%a6), 4+FP_SRC(%a6)
	mov.l		8+EXC_FP1(%a6), 8+FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts
load_fpn1_2:
	fmovm.x		&0x20, FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts
load_fpn1_3:
	fmovm.x		&0x10, FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts
load_fpn1_4:
	fmovm.x		&0x08, FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts
load_fpn1_5:
	fmovm.x		&0x04, FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts
load_fpn1_6:
	fmovm.x		&0x02, FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts
load_fpn1_7:
	fmovm.x		&0x01, FP_SRC(%a6)
	lea		FP_SRC(%a6), %a0
	rts

#############################################################################

#########################################################################
# XDEF ****************************************************************	#
#	load_fpn2(): load FP register value into FP_DST(a6).		#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	d0 = index of FP register to load				#
# 									#
# OUTPUT **************************************************************	#
#	FP_DST(a6) = value loaded from FP register file			#
#									#
# ALGORITHM ***********************************************************	#
#	Using the index in d0, load FP_DST(a6) with a number from the 	#
# FP register file.							#
#									#
#########################################################################

	global		load_fpn2
load_fpn2:
	mov.w		(tbl_load_fpn2.b,%pc,%d0.w*2), %d0
	jmp		(tbl_load_fpn2.b,%pc,%d0.w*1)

tbl_load_fpn2:
	short		load_fpn2_0 - tbl_load_fpn2
	short		load_fpn2_1 - tbl_load_fpn2
	short		load_fpn2_2 - tbl_load_fpn2
	short		load_fpn2_3 - tbl_load_fpn2
	short		load_fpn2_4 - tbl_load_fpn2
	short		load_fpn2_5 - tbl_load_fpn2
	short		load_fpn2_6 - tbl_load_fpn2
	short		load_fpn2_7 - tbl_load_fpn2

load_fpn2_0:
	mov.l		0+EXC_FP0(%a6), 0+FP_DST(%a6)
	mov.l		4+EXC_FP0(%a6), 4+FP_DST(%a6)
	mov.l		8+EXC_FP0(%a6), 8+FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts
load_fpn2_1:
	mov.l		0+EXC_FP1(%a6), 0+FP_DST(%a6)
	mov.l		4+EXC_FP1(%a6), 4+FP_DST(%a6)
	mov.l		8+EXC_FP1(%a6), 8+FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts
load_fpn2_2:
	fmovm.x		&0x20, FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts
load_fpn2_3:
	fmovm.x		&0x10, FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts
load_fpn2_4:
	fmovm.x		&0x08, FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts
load_fpn2_5:
	fmovm.x		&0x04, FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts
load_fpn2_6:
	fmovm.x		&0x02, FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts
load_fpn2_7:
	fmovm.x		&0x01, FP_DST(%a6)
	lea		FP_DST(%a6), %a0
	rts

#############################################################################

#########################################################################
# XDEF ****************************************************************	#
# 	store_fpreg(): store an fp value to the fpreg designated d0.	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	fp0 = extended precision value to store				#
#	d0  = index of floating-point register				#
# 									#
# OUTPUT **************************************************************	#
#	None								#
#									#
# ALGORITHM ***********************************************************	#
#	Store the value in fp0 to the FP register designated by the	#
# value in d0. The FP number can be DENORM or SNAN so we have to be	#
# careful that we don't take an exception here.				#
#									#
#########################################################################

	global		store_fpreg
store_fpreg:
	mov.w		(tbl_store_fpreg.b,%pc,%d0.w*2), %d0
	jmp		(tbl_store_fpreg.b,%pc,%d0.w*1)

tbl_store_fpreg:
	short		store_fpreg_0 - tbl_store_fpreg
	short		store_fpreg_1 - tbl_store_fpreg
	short		store_fpreg_2 - tbl_store_fpreg
	short		store_fpreg_3 - tbl_store_fpreg
	short		store_fpreg_4 - tbl_store_fpreg
	short		store_fpreg_5 - tbl_store_fpreg
	short		store_fpreg_6 - tbl_store_fpreg
	short		store_fpreg_7 - tbl_store_fpreg

store_fpreg_0:
	fmovm.x		&0x80, EXC_FP0(%a6)
	rts
store_fpreg_1:
	fmovm.x		&0x80, EXC_FP1(%a6)
	rts
store_fpreg_2:
	fmovm.x 	&0x01, -(%sp)
	fmovm.x		(%sp)+, &0x20
	rts
store_fpreg_3:
	fmovm.x 	&0x01, -(%sp)
	fmovm.x		(%sp)+, &0x10
	rts
store_fpreg_4:
	fmovm.x 	&0x01, -(%sp)
	fmovm.x		(%sp)+, &0x08
	rts
store_fpreg_5:
	fmovm.x 	&0x01, -(%sp)
	fmovm.x		(%sp)+, &0x04
	rts
store_fpreg_6:
	fmovm.x 	&0x01, -(%sp)
	fmovm.x		(%sp)+, &0x02
	rts
store_fpreg_7:
	fmovm.x 	&0x01, -(%sp)
	fmovm.x		(%sp)+, &0x01
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	_denorm(): denormalize an intermediate result			#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT *************************************************************** #
#	a0 = points to the operand to be denormalized			#
#		(in the internal extended format)			#
#		 							#
#	d0 = rounding precision						#
#									#
# OUTPUT **************************************************************	#
#	a0 = pointer to the denormalized result				#
#		(in the internal extended format)			#
#									#
#	d0 = guard,round,sticky						#
#									#
# ALGORITHM ***********************************************************	#
# 	According to the exponent underflow threshold for the given	#
# precision, shift the mantissa bits to the right in order raise the	#
# exponent of the operand to the threshold value. While shifting the 	#
# mantissa bits right, maintain the value of the guard, round, and 	#
# sticky bits.								#
# other notes:								#
#	(1) _denorm() is called by the underflow routines		#
#	(2) _denorm() does NOT affect the status register		#
#									#
#########################################################################

#
# table of exponent threshold values for each precision
#
tbl_thresh:
	short		0x0
	short		sgl_thresh
	short		dbl_thresh

	global		_denorm
_denorm:
#
# Load the exponent threshold for the precision selected and check
# to see if (threshold - exponent) is > 65 in which case we can 
# simply calculate the sticky bit and zero the mantissa. otherwise
# we have to call the denormalization routine.
#
	lsr.b		&0x2, %d0		# shift prec to lo bits
	mov.w		(tbl_thresh.b,%pc,%d0.w*2), %d1 # load prec threshold
	mov.w		%d1, %d0		# copy d1 into d0
	sub.w		FTEMP_EX(%a0), %d0	# diff = threshold - exp
	cmpi.w		%d0, &66		# is diff > 65? (mant + g,r bits)
	bpl.b		denorm_set_stky		# yes; just calc sticky

	clr.l		%d0			# clear g,r,s
	btst		&inex2_bit, FPSR_EXCEPT(%a6) # yes; was INEX2 set?
	beq.b		denorm_call		# no; don't change anything
	bset		&29, %d0		# yes; set sticky bit

denorm_call:
	bsr.l		dnrm_lp			# denormalize the number
	rts

#
# all bit would have been shifted off during the denorm so simply
# calculate if the sticky should be set and clear the entire mantissa.
#
denorm_set_stky:
	mov.l		&0x20000000, %d0	# set sticky bit in return value
	mov.w		%d1, FTEMP_EX(%a0)	# load exp with threshold
	clr.l		FTEMP_HI(%a0)		# set d1 = 0 (ms mantissa)
	clr.l		FTEMP_LO(%a0)		# set d2 = 0 (ms mantissa)
	rts

#									#
# dnrm_lp(): normalize exponent/mantissa to specified threshhold	#
#									#
# INPUT:								#
#	%a0	   : points to the operand to be denormalized		#
#	%d0{31:29} : initial guard,round,sticky				#
#	%d1{15:0}  : denormalization threshold				#
# OUTPUT:								#
#	%a0	   : points to the denormalized operand		 	#
#	%d0{31:29} : final guard,round,sticky				#
#									#

# *** Local Equates *** #
set	GRS,		L_SCR2			# g,r,s temp storage
set	FTEMP_LO2,	L_SCR1			# FTEMP_LO copy

	global		dnrm_lp
dnrm_lp:

#
# make a copy of FTEMP_LO and place the g,r,s bits directly after it
# in memory so as to make the bitfield extraction for denormalization easier.
#
	mov.l		FTEMP_LO(%a0), FTEMP_LO2(%a6) # make FTEMP_LO copy
	mov.l		%d0, GRS(%a6)		# place g,r,s after it

#
# check to see how much less than the underflow threshold the operand
# exponent is. 
#
	mov.l		%d1, %d0		# copy the denorm threshold
	sub.w		FTEMP_EX(%a0), %d1	# d1 = threshold - uns exponent
	ble.b		dnrm_no_lp		# d1 <= 0
	cmpi.w		%d1, &0x20		# is ( 0 <= d1 < 32) ?
	blt.b		case_1			# yes
	cmpi.w		%d1, &0x40		# is (32 <= d1 < 64) ?
	blt.b		case_2			# yes
	bra.w		case_3			# (d1 >= 64)

#
# No normalization necessary
#
dnrm_no_lp:
	mov.l		GRS(%a6), %d0 		# restore original g,r,s
	rts

#
# case (0<d1<32)
#
# %d0 = denorm threshold
# %d1 = "n" = amt to shift
#
#	---------------------------------------------------------
#	|     FTEMP_HI	  |    	FTEMP_LO     |grs000.........000|
#	---------------------------------------------------------
#	<-(32 - n)-><-(n)-><-(32 - n)-><-(n)-><-(32 - n)-><-(n)->
#	\	   \		      \			 \
#	 \	    \		       \		  \
#	  \	     \			\		   \
#	   \	      \			 \		    \
#	    \	       \		  \		     \
#	     \		\		   \		      \
#	      \		 \		    \		       \
#	       \	  \		     \			\
#	<-(n)-><-(32 - n)-><------(32)-------><------(32)------->	
#	---------------------------------------------------------
#	|0.....0| NEW_HI  |  NEW_FTEMP_LO     |grs		|
#	---------------------------------------------------------
#
case_1:
	mov.l		%d2, -(%sp)		# create temp storage

	mov.w		%d0, FTEMP_EX(%a0)	# exponent = denorm threshold
	mov.l		&32, %d0
	sub.w		%d1, %d0		# %d0 = 32 - %d1

	cmpi.w		%d1, &29		# is shft amt >= 29
	blt.b		case1_extract		# no; no fix needed
	mov.b		GRS(%a6), %d2
	or.b		%d2, 3+FTEMP_LO2(%a6)

case1_extract:
	bfextu		FTEMP_HI(%a0){&0:%d0}, %d2 # %d2 = new FTEMP_HI
	bfextu		FTEMP_HI(%a0){%d0:&32}, %d1 # %d1 = new FTEMP_LO
	bfextu		FTEMP_LO2(%a6){%d0:&32}, %d0 # %d0 = new G,R,S

	mov.l		%d2, FTEMP_HI(%a0)	# store new FTEMP_HI
	mov.l		%d1, FTEMP_LO(%a0)	# store new FTEMP_LO

	bftst		%d0{&2:&30}		# were bits shifted off?
	beq.b		case1_sticky_clear	# no; go finish
	bset		&rnd_stky_bit, %d0	# yes; set sticky bit

case1_sticky_clear:
	and.l		&0xe0000000, %d0	# clear all but G,R,S
	mov.l		(%sp)+, %d2		# restore temp register
	rts

#
# case (32<=d1<64)
#
# %d0 = denorm threshold
# %d1 = "n" = amt to shift
#
#	---------------------------------------------------------
#	|     FTEMP_HI	  |    	FTEMP_LO     |grs000.........000|
#	---------------------------------------------------------
#	<-(32 - n)-><-(n)-><-(32 - n)-><-(n)-><-(32 - n)-><-(n)->
#	\	   \		      \
#	 \	    \		       \
#	  \	     \			-------------------
#	   \	      --------------------		   \
#	    -------------------	  	  \		    \
#	     		       \	   \		     \
#	      		 	\     	    \		      \
#	       		  	 \	     \		       \
#	<-------(32)------><-(n)-><-(32 - n)-><------(32)------->
#	---------------------------------------------------------
#	|0...............0|0....0| NEW_LO     |grs		|
#	---------------------------------------------------------
#
case_2:
	mov.l		%d2, -(%sp)		# create temp storage

	mov.w		%d0, FTEMP_EX(%a0)	# exponent = denorm threshold
	subi.w		&0x20, %d1		# %d1 now between 0 and 32
	mov.l		&0x20, %d0
	sub.w		%d1, %d0		# %d0 = 32 - %d1

# subtle step here; or in the g,r,s at the bottom of FTEMP_LO to minimize
# the number of bits to check for the sticky detect.
# it only plays a role in shift amounts of 61-63.
	mov.b		GRS(%a6), %d2
	or.b		%d2, 3+FTEMP_LO2(%a6)

	bfextu		FTEMP_HI(%a0){&0:%d0}, %d2 # %d2 = new FTEMP_LO
	bfextu		FTEMP_HI(%a0){%d0:&32}, %d1 # %d1 = new G,R,S

	bftst		%d1{&2:&30}		# were any bits shifted off?
	bne.b		case2_set_sticky	# yes; set sticky bit
	bftst		FTEMP_LO2(%a6){%d0:&31}	# were any bits shifted off?
	bne.b		case2_set_sticky	# yes; set sticky bit

	mov.l		%d1, %d0		# move new G,R,S to %d0
	bra.b		case2_end

case2_set_sticky:
	mov.l		%d1, %d0		# move new G,R,S to %d0
	bset		&rnd_stky_bit, %d0	# set sticky bit

case2_end:
	clr.l		FTEMP_HI(%a0)		# store FTEMP_HI = 0
	mov.l		%d2, FTEMP_LO(%a0)	# store FTEMP_LO
	and.l		&0xe0000000, %d0	# clear all but G,R,S

	mov.l		(%sp)+,%d2		# restore temp register
	rts

#
# case (d1>=64)
#
# %d0 = denorm threshold
# %d1 = amt to shift
#
case_3:
	mov.w		%d0, FTEMP_EX(%a0)	# insert denorm threshold

	cmpi.w		%d1, &65		# is shift amt > 65?
	blt.b		case3_64		# no; it's == 64
	beq.b		case3_65		# no; it's == 65

#
# case (d1>65)
#
# Shift value is > 65 and out of range. All bits are shifted off.
# Return a zero mantissa with the sticky bit set
#
	clr.l		FTEMP_HI(%a0)		# clear hi(mantissa)
	clr.l		FTEMP_LO(%a0)		# clear lo(mantissa)
	mov.l		&0x20000000, %d0	# set sticky bit
	rts

#
# case (d1 == 64)
#
#	---------------------------------------------------------
#	|     FTEMP_HI	  |    	FTEMP_LO     |grs000.........000|
#	---------------------------------------------------------
#	<-------(32)------>
#	\	   	   \
#	 \	    	    \
#	  \	     	     \
#	   \	      	      ------------------------------
#	    -------------------------------		    \
#	     		       		   \		     \
#	      		 	     	    \		      \
#	       		  	 	     \		       \
#					      <-------(32)------>
#	---------------------------------------------------------
#	|0...............0|0................0|grs		|
#	---------------------------------------------------------
#
case3_64:
	mov.l		FTEMP_HI(%a0), %d0	# fetch hi(mantissa)
	mov.l		%d0, %d1		# make a copy
	and.l		&0xc0000000, %d0	# extract G,R
	and.l		&0x3fffffff, %d1	# extract other bits

	bra.b		case3_complete

#
# case (d1 == 65)
#
#	---------------------------------------------------------
#	|     FTEMP_HI	  |    	FTEMP_LO     |grs000.........000|
#	---------------------------------------------------------
#	<-------(32)------>
#	\	   	   \
#	 \	    	    \
#	  \	     	     \
#	   \	      	      ------------------------------
#	    --------------------------------		    \
#	     		       		    \		     \
#	      		 	     	     \		      \
#	       		  	 	      \		       \
#					       <-------(31)----->
#	---------------------------------------------------------
#	|0...............0|0................0|0rs		|
#	---------------------------------------------------------
#
case3_65:
	mov.l		FTEMP_HI(%a0), %d0	# fetch hi(mantissa)
	and.l		&0x80000000, %d0	# extract R bit
	lsr.l		&0x1, %d0		# shift high bit into R bit
	and.l		&0x7fffffff, %d1	# extract other bits

case3_complete:
# last operation done was an "and" of the bits shifted off so the condition
# codes are already set so branch accordingly.
	bne.b		case3_set_sticky	# yes; go set new sticky
	tst.l		FTEMP_LO(%a0)		# were any bits shifted off?
	bne.b		case3_set_sticky	# yes; go set new sticky
	tst.b		GRS(%a6)		# were any bits shifted off?
	bne.b		case3_set_sticky	# yes; go set new sticky

#
# no bits were shifted off so don't set the sticky bit.
# the guard and
# the entire mantissa is zero.
#
	clr.l		FTEMP_HI(%a0)		# clear hi(mantissa)
	clr.l		FTEMP_LO(%a0)		# clear lo(mantissa)
	rts

#
# some bits were shifted off so set the sticky bit.
# the entire mantissa is zero.
#
case3_set_sticky:
	bset		&rnd_stky_bit,%d0	# set new sticky bit
	clr.l		FTEMP_HI(%a0)		# clear hi(mantissa)
	clr.l		FTEMP_LO(%a0)		# clear lo(mantissa)
	rts

#########################################################################
# XDEF ****************************************************************	#
#	_round(): round result according to precision/mode		#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	a0	  = ptr to input operand in internal extended format 	#
#	d1(hi)    = contains rounding precision:			#
#			ext = $0000xxxx					#
#			sgl = $0004xxxx					#
#			dbl = $0008xxxx					#
#	d1(lo)	  = contains rounding mode:				#
#			RN  = $xxxx0000					#
#			RZ  = $xxxx0001					#
#			RM  = $xxxx0002					#
#			RP  = $xxxx0003					#
#	d0{31:29} = contains the g,r,s bits (extended)			#
#									#
# OUTPUT **************************************************************	#
#	a0 = pointer to rounded result					#
#									#
# ALGORITHM ***********************************************************	#
#	On return the value pointed to by a0 is correctly rounded,	#
#	a0 is preserved and the g-r-s bits in d0 are cleared.		#
#	The result is not typed - the tag field is invalid.  The	#
#	result is still in the internal extended format.		#
#									#
#	The INEX bit of USER_FPSR will be set if the rounded result was	#
#	inexact (i.e. if any of the g-r-s bits were set).		#
#									#
#########################################################################

	global		_round
_round:
#
# ext_grs() looks at the rounding precision and sets the appropriate
# G,R,S bits.
# If (G,R,S == 0) then result is exact and round is done, else set 
# the inex flag in status reg and continue.
#
	bsr.l		ext_grs			# extract G,R,S

	tst.l		%d0			# are G,R,S zero?
	beq.w		truncate		# yes; round is complete

	or.w		&inx2a_mask, 2+USER_FPSR(%a6) # set inex2/ainex

#
# Use rounding mode as an index into a jump table for these modes.
# All of the following assumes grs != 0.
#
	mov.w		(tbl_mode.b,%pc,%d1.w*2), %a1 # load jump offset
	jmp		(tbl_mode.b,%pc,%a1)	# jmp to rnd mode handler

tbl_mode:
	short		rnd_near - tbl_mode
	short		truncate - tbl_mode	# RZ always truncates
	short		rnd_mnus - tbl_mode
	short		rnd_plus - tbl_mode

#################################################################
#	ROUND PLUS INFINITY					#
#								#
#	If sign of fp number = 0 (positive), then add 1 to l.	#
#################################################################
rnd_plus:
	tst.b		FTEMP_SGN(%a0)		# check for sign
	bmi.w		truncate		# if positive then truncate

	mov.l		&0xffffffff, %d0	# force g,r,s to be all f's
	swap		%d1			# set up d1 for round prec.

	cmpi.b		%d1, &s_mode		# is prec = sgl?
	beq.w		add_sgl			# yes
	bgt.w		add_dbl			# no; it's dbl
	bra.w		add_ext			# no; it's ext

#################################################################
#	ROUND MINUS INFINITY					#
#								#
#	If sign of fp number = 1 (negative), then add 1 to l.	#
#################################################################
rnd_mnus:
	tst.b		FTEMP_SGN(%a0)		# check for sign	
	bpl.w		truncate		# if negative then truncate

	mov.l		&0xffffffff, %d0	# force g,r,s to be all f's
	swap		%d1			# set up d1 for round prec.

	cmpi.b		%d1, &s_mode		# is prec = sgl?
	beq.w		add_sgl			# yes
	bgt.w		add_dbl			# no; it's dbl
	bra.w		add_ext			# no; it's ext

#################################################################
#	ROUND NEAREST						#
#								#
#	If (g=1), then add 1 to l and if (r=s=0), then clear l	#
#	Note that this will round to even in case of a tie.	#
#################################################################
rnd_near:
	asl.l		&0x1, %d0		# shift g-bit to c-bit
	bcc.w		truncate		# if (g=1) then

	swap		%d1			# set up d1 for round prec.

	cmpi.b		%d1, &s_mode		# is prec = sgl?
	beq.w		add_sgl			# yes
	bgt.w		add_dbl			# no; it's dbl
	bra.w		add_ext			# no; it's ext

# *** LOCAL EQUATES ***
set	ad_1_sgl,	0x00000100	# constant to add 1 to l-bit in sgl prec
set	ad_1_dbl,	0x00000800	# constant to add 1 to l-bit in dbl prec

#########################
#	ADD SINGLE	#
#########################
add_sgl:
	add.l		&ad_1_sgl, FTEMP_HI(%a0)
	bcc.b		scc_clr			# no mantissa overflow
	roxr.w		FTEMP_HI(%a0)		# shift v-bit back in
	roxr.w		FTEMP_HI+2(%a0)		# shift v-bit back in
	add.w		&0x1, FTEMP_EX(%a0)	# and incr exponent
scc_clr:
	tst.l		%d0			# test for rs = 0
	bne.b		sgl_done
	and.w		&0xfe00, FTEMP_HI+2(%a0) # clear the l-bit
sgl_done:
	and.l		&0xffffff00, FTEMP_HI(%a0) # truncate bits beyond sgl limit
	clr.l		FTEMP_LO(%a0)		# clear d2
	rts

#########################
#	ADD EXTENDED	#
#########################
add_ext:
	addq.l		&1,FTEMP_LO(%a0)	# add 1 to l-bit
	bcc.b		xcc_clr			# test for carry out
	addq.l		&1,FTEMP_HI(%a0)	# propogate carry
	bcc.b		xcc_clr
	roxr.w		FTEMP_HI(%a0)		# mant is 0 so restore v-bit
	roxr.w		FTEMP_HI+2(%a0)		# mant is 0 so restore v-bit
	roxr.w		FTEMP_LO(%a0)
	roxr.w		FTEMP_LO+2(%a0)
	add.w		&0x1,FTEMP_EX(%a0)	# and inc exp
xcc_clr:
	tst.l		%d0			# test rs = 0
	bne.b		add_ext_done
	and.b		&0xfe,FTEMP_LO+3(%a0)	# clear the l bit
add_ext_done:
	rts

#########################
#	ADD DOUBLE	#
#########################
add_dbl:
	add.l		&ad_1_dbl, FTEMP_LO(%a0) # add 1 to lsb
	bcc.b		dcc_clr			# no carry
	addq.l		&0x1, FTEMP_HI(%a0)	# propogate carry
	bcc.b		dcc_clr			# no carry

	roxr.w		FTEMP_HI(%a0)		# mant is 0 so restore v-bit
	roxr.w		FTEMP_HI+2(%a0)		# mant is 0 so restore v-bit
	roxr.w		FTEMP_LO(%a0)
	roxr.w		FTEMP_LO+2(%a0)
	addq.w		&0x1, FTEMP_EX(%a0)	# incr exponent
dcc_clr:
	tst.l		%d0			# test for rs = 0
	bne.b		dbl_done
	and.w		&0xf000, FTEMP_LO+2(%a0) # clear the l-bit

dbl_done:
	and.l		&0xfffff800,FTEMP_LO(%a0) # truncate bits beyond dbl limit
	rts

###########################
# Truncate all other bits #
###########################
truncate:
	swap		%d1			# select rnd prec

	cmpi.b		%d1, &s_mode		# is prec sgl?
	beq.w		sgl_done		# yes
	bgt.b		dbl_done		# no; it's dbl
	rts					# no; it's ext


#
# ext_grs(): extract guard, round and sticky bits according to
#	     rounding precision.
#
# INPUT
#	d0	   = extended precision g,r,s (in d0{31:29})
#	d1 	   = {PREC,ROUND}
# OUTPUT
#	d0{31:29}  = guard, round, sticky
#
# The ext_grs extract the guard/round/sticky bits according to the
# selected rounding precision. It is called by the round subroutine
# only.  All registers except d0 are kept intact. d0 becomes an
# updated guard,round,sticky in d0{31:29}
#
# Notes: the ext_grs uses the round PREC, and therefore has to swap d1
#	 prior to usage, and needs to restore d1 to original. this
#	 routine is tightly tied to the round routine and not meant to
#	 uphold standard subroutine calling practices.
#

ext_grs:
	swap		%d1			# have d1.w point to round precision
	tst.b		%d1			# is rnd prec = extended?
	bne.b		ext_grs_not_ext		# no; go handle sgl or dbl

#
# %d0 actually already hold g,r,s since _round() had it before calling
# this function. so, as long as we don't disturb it, we are "returning" it.
#
ext_grs_ext:
	swap		%d1			# yes; return to correct positions
	rts

ext_grs_not_ext:
	movm.l		&0x3000, -(%sp)		# make some temp registers {d2/d3}

	cmpi.b		%d1, &s_mode		# is rnd prec = sgl?
	bne.b		ext_grs_dbl		# no; go handle dbl

#
# sgl:
#	96		64	  40	32		0
#	-----------------------------------------------------
#	| EXP	|XXXXXXX|	  |xx	|		|grs|
#	-----------------------------------------------------
#			<--(24)--->nn\			   /
#				   ee ---------------------
#				   ww		|
#						v
#				   gr	   new sticky
#
ext_grs_sgl:
	bfextu		FTEMP_HI(%a0){&24:&2}, %d3 # sgl prec. g-r are 2 bits right
	mov.l		&30, %d2		# of the sgl prec. limits
	lsl.l		%d2, %d3		# shift g-r bits to MSB of d3
	mov.l		FTEMP_HI(%a0), %d2	# get word 2 for s-bit test
	and.l		&0x0000003f, %d2	# s bit is the or of all other 
	bne.b		ext_grs_st_stky		# bits to the right of g-r
	tst.l		FTEMP_LO(%a0)		# test lower mantissa
	bne.b		ext_grs_st_stky		# if any are set, set sticky
	tst.l		%d0			# test original g,r,s
	bne.b		ext_grs_st_stky		# if any are set, set sticky
	bra.b		ext_grs_end_sd		# if words 3 and 4 are clr, exit

#
# dbl:
#	96		64	  	32	 11	0
#	-----------------------------------------------------
#	| EXP	|XXXXXXX|	  	|	 |xx	|grs|
#	-----------------------------------------------------
#						  nn\	    /
#						  ee -------
#						  ww	|
#							v
#						  gr	new sticky
#
ext_grs_dbl:
	bfextu		FTEMP_LO(%a0){&21:&2}, %d3 # dbl-prec. g-r are 2 bits right
	mov.l		&30, %d2		# of the dbl prec. limits
	lsl.l		%d2, %d3		# shift g-r bits to the MSB of d3
	mov.l		FTEMP_LO(%a0), %d2	# get lower mantissa  for s-bit test
	and.l		&0x000001ff, %d2	# s bit is the or-ing of all 
	bne.b		ext_grs_st_stky		# other bits to the right of g-r
	tst.l		%d0			# test word original g,r,s
	bne.b		ext_grs_st_stky		# if any are set, set sticky
	bra.b		ext_grs_end_sd		# if clear, exit

ext_grs_st_stky:
	bset		&rnd_stky_bit, %d3	# set sticky bit
ext_grs_end_sd:
	mov.l		%d3, %d0		# return grs to d0

	movm.l		(%sp)+, &0xc		# restore scratch registers {d2/d3}

	swap		%d1			# restore d1 to original
	rts

#########################################################################
# norm(): normalize the mantissa of an extended precision input. the	#
#	  input operand should not be normalized already.		#
#									#
# XDEF ****************************************************************	#
#	norm()								#
#									#
# XREF **************************************************************** #
#	none								#
#									#
# INPUT *************************************************************** #
#	a0 = pointer fp extended precision operand to normalize		#
#									#
# OUTPUT ************************************************************** #
# 	d0 = number of bit positions the mantissa was shifted		#
#	a0 = the input operand's mantissa is normalized; the exponent	#
#	     is unchanged.						#
#									#
#########################################################################
	global		norm
norm:
	mov.l		%d2, -(%sp)		# create some temp regs
	mov.l		%d3, -(%sp)

	mov.l		FTEMP_HI(%a0), %d0	# load hi(mantissa)
	mov.l		FTEMP_LO(%a0), %d1	# load lo(mantissa)

	bfffo		%d0{&0:&32}, %d2	# how many places to shift?
	beq.b		norm_lo			# hi(man) is all zeroes!

norm_hi:
	lsl.l		%d2, %d0		# left shift hi(man)
	bfextu		%d1{&0:%d2}, %d3	# extract lo bits

	or.l		%d3, %d0		# create hi(man)
	lsl.l		%d2, %d1		# create lo(man)

	mov.l		%d0, FTEMP_HI(%a0)	# store new hi(man)
	mov.l		%d1, FTEMP_LO(%a0)	# store new lo(man)

	mov.l		%d2, %d0		# return shift amount
	
	mov.l		(%sp)+, %d3		# restore temp regs
	mov.l		(%sp)+, %d2

	rts

norm_lo:
	bfffo		%d1{&0:&32}, %d2	# how many places to shift?
	lsl.l		%d2, %d1		# shift lo(man)
	add.l		&32, %d2		# add 32 to shft amount

	mov.l		%d1, FTEMP_HI(%a0)	# store hi(man)
	clr.l		FTEMP_LO(%a0)		# lo(man) is now zero

	mov.l		%d2, %d0		# return shift amount
	
	mov.l		(%sp)+, %d3		# restore temp regs
	mov.l		(%sp)+, %d2

	rts

#########################################################################
# unnorm_fix(): - changes an UNNORM to one of NORM, DENORM, or ZERO	#
#		- returns corresponding optype tag			#
#									#
# XDEF ****************************************************************	#
#	unnorm_fix()							#
#									#
# XREF **************************************************************** #
#	norm() - normalize the mantissa					#
#									#
# INPUT *************************************************************** #
#	a0 = pointer to unnormalized extended precision number		#
#									#
# OUTPUT ************************************************************** #
#	d0 = optype tag - is corrected to one of NORM, DENORM, or ZERO	#
#	a0 = input operand has been converted to a norm, denorm, or	#
#	     zero; both the exponent and mantissa are changed.		#
#									#
#########################################################################

	global		unnorm_fix
unnorm_fix:
	bfffo		FTEMP_HI(%a0){&0:&32}, %d0 # how many shifts are needed?
	bne.b		unnorm_shift		# hi(man) is not all zeroes

#
# hi(man) is all zeroes so see if any bits in lo(man) are set
#
unnorm_chk_lo:
	bfffo		FTEMP_LO(%a0){&0:&32}, %d0 # is operand really a zero?
	beq.w		unnorm_zero		# yes

	add.w		&32, %d0		# no; fix shift distance

#
# d0 = # shifts needed for complete normalization
#
unnorm_shift:
	clr.l		%d1			# clear top word
	mov.w		FTEMP_EX(%a0), %d1	# extract exponent
	and.w		&0x7fff, %d1		# strip off sgn

	cmp.w		%d0, %d1		# will denorm push exp < 0?
	bgt.b		unnorm_nrm_zero		# yes; denorm only until exp = 0

#
# exponent would not go < 0. therefore, number stays normalized
#
	sub.w		%d0, %d1		# shift exponent value
	mov.w		FTEMP_EX(%a0), %d0	# load old exponent
	and.w		&0x8000, %d0		# save old sign
	or.w		%d0, %d1		# {sgn,new exp}
	mov.w		%d1, FTEMP_EX(%a0)	# insert new exponent

	bsr.l		norm			# normalize UNNORM

	mov.b		&NORM, %d0		# return new optype tag
	rts

#
# exponent would go < 0, so only denormalize until exp = 0
#
unnorm_nrm_zero:
	cmp.b		%d1, &32		# is exp <= 32?
	bgt.b		unnorm_nrm_zero_lrg	# no; go handle large exponent

	bfextu		FTEMP_HI(%a0){%d1:&32}, %d0 # extract new hi(man)
	mov.l		%d0, FTEMP_HI(%a0)	# save new hi(man)

	mov.l		FTEMP_LO(%a0), %d0	# fetch old lo(man)
	lsl.l		%d1, %d0		# extract new lo(man)
	mov.l		%d0, FTEMP_LO(%a0)	# save new lo(man)

	and.w		&0x8000, FTEMP_EX(%a0)	# set exp = 0

	mov.b		&DENORM, %d0		# return new optype tag
	rts

#
# only mantissa bits set are in lo(man)
#
unnorm_nrm_zero_lrg:
	sub.w		&32, %d1		# adjust shft amt by 32

	mov.l		FTEMP_LO(%a0), %d0	# fetch old lo(man)
	lsl.l		%d1, %d0		# left shift lo(man)

	mov.l		%d0, FTEMP_HI(%a0)	# store new hi(man)
	clr.l		FTEMP_LO(%a0)		# lo(man) = 0

	and.w		&0x8000, FTEMP_EX(%a0)	# set exp = 0

	mov.b		&DENORM, %d0		# return new optype tag
	rts

#
# whole mantissa is zero so this UNNORM is actually a zero
#
unnorm_zero:
	and.w		&0x8000, FTEMP_EX(%a0) 	# force exponent to zero

	mov.b		&ZERO, %d0		# fix optype tag
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	set_tag_x(): return the optype of the input ext fp number	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precision operand			#
# 									#
# OUTPUT **************************************************************	#
#	d0 = value of type tag						#
# 		one of: NORM, INF, QNAN, SNAN, DENORM, UNNORM, ZERO	#
#									#
# ALGORITHM ***********************************************************	#
#	Simply test the exponent, j-bit, and mantissa values to 	#
# determine the type of operand.					#
#	If it's an unnormalized zero, alter the operand and force it	#
# to be a normal zero.							#
#									#
#########################################################################

	global		set_tag_x
set_tag_x:
	mov.w		FTEMP_EX(%a0), %d0	# extract exponent
	andi.w		&0x7fff, %d0		# strip off sign
	cmpi.w		%d0, &0x7fff		# is (EXP == MAX)?
	beq.b		inf_or_nan_x
not_inf_or_nan_x:
	btst		&0x7,FTEMP_HI(%a0)
	beq.b		not_norm_x
is_norm_x:
	mov.b		&NORM, %d0
	rts
not_norm_x:
	tst.w		%d0			# is exponent = 0?
	bne.b		is_unnorm_x
not_unnorm_x:
	tst.l		FTEMP_HI(%a0)
	bne.b		is_denorm_x
	tst.l		FTEMP_LO(%a0)
	bne.b		is_denorm_x
is_zero_x:
	mov.b		&ZERO, %d0
	rts
is_denorm_x:
	mov.b		&DENORM, %d0
	rts
# must distinguish now "Unnormalized zeroes" which we
# must convert to zero.
is_unnorm_x:
	tst.l		FTEMP_HI(%a0)
	bne.b		is_unnorm_reg_x
	tst.l		FTEMP_LO(%a0)
	bne.b		is_unnorm_reg_x
# it's an "unnormalized zero". let's convert it to an actual zero...
	andi.w		&0x8000,FTEMP_EX(%a0)	# clear exponent
	mov.b		&ZERO, %d0
	rts
is_unnorm_reg_x:
	mov.b		&UNNORM, %d0
	rts
inf_or_nan_x:
	tst.l		FTEMP_LO(%a0)
	bne.b		is_nan_x
	mov.l		FTEMP_HI(%a0), %d0
	and.l		&0x7fffffff, %d0	# msb is a don't care!
	bne.b		is_nan_x
is_inf_x:
	mov.b		&INF, %d0
	rts
is_nan_x:
	btst		&0x6, FTEMP_HI(%a0)
	beq.b		is_snan_x
	mov.b		&QNAN, %d0
	rts
is_snan_x:
	mov.b		&SNAN, %d0
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	set_tag_d(): return the optype of the input dbl fp number	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	a0 = points to double precision operand				#
# 									#
# OUTPUT **************************************************************	#
#	d0 = value of type tag						#
# 		one of: NORM, INF, QNAN, SNAN, DENORM, ZERO		#
#									#
# ALGORITHM ***********************************************************	#
#	Simply test the exponent, j-bit, and mantissa values to 	#
# determine the type of operand.					#
#									#
#########################################################################

	global		set_tag_d
set_tag_d:
	mov.l		FTEMP(%a0), %d0
	mov.l		%d0, %d1

	andi.l		&0x7ff00000, %d0
	beq.b		zero_or_denorm_d

	cmpi.l		%d0, &0x7ff00000
	beq.b		inf_or_nan_d

is_norm_d:
	mov.b		&NORM, %d0
	rts
zero_or_denorm_d:
	and.l		&0x000fffff, %d1
	bne		is_denorm_d
	tst.l		4+FTEMP(%a0)
	bne		is_denorm_d
is_zero_d:
	mov.b		&ZERO, %d0
	rts
is_denorm_d:
	mov.b		&DENORM, %d0
	rts
inf_or_nan_d:
	and.l		&0x000fffff, %d1
	bne		is_nan_d
	tst.l		4+FTEMP(%a0)
	bne		is_nan_d
is_inf_d:
	mov.b		&INF, %d0
	rts
is_nan_d:
	btst		&19, %d1
	bne		is_qnan_d
is_snan_d:
	mov.b		&SNAN, %d0
	rts
is_qnan_d:
	mov.b		&QNAN, %d0
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	set_tag_s(): return the optype of the input sgl fp number	#
#									#
# XREF ****************************************************************	#
#	None								#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to single precision operand			#
# 									#
# OUTPUT **************************************************************	#
#	d0 = value of type tag						#
# 		one of: NORM, INF, QNAN, SNAN, DENORM, ZERO		#
#									#
# ALGORITHM ***********************************************************	#
#	Simply test the exponent, j-bit, and mantissa values to 	#
# determine the type of operand.					#
#									#
#########################################################################

	global		set_tag_s
set_tag_s:
	mov.l		FTEMP(%a0), %d0
	mov.l		%d0, %d1

	andi.l		&0x7f800000, %d0
	beq.b		zero_or_denorm_s

	cmpi.l		%d0, &0x7f800000
	beq.b		inf_or_nan_s

is_norm_s:
	mov.b		&NORM, %d0
	rts
zero_or_denorm_s:
	and.l		&0x007fffff, %d1
	bne		is_denorm_s
is_zero_s:
	mov.b		&ZERO, %d0
	rts
is_denorm_s:
	mov.b		&DENORM, %d0
	rts
inf_or_nan_s:
	and.l		&0x007fffff, %d1
	bne		is_nan_s
is_inf_s:
	mov.b		&INF, %d0
	rts
is_nan_s:
	btst		&22, %d1
	bne		is_qnan_s
is_snan_s:
	mov.b		&SNAN, %d0
	rts
is_qnan_s:
	mov.b		&QNAN, %d0
	rts

#########################################################################
# XDEF ****************************************************************	#
# 	unf_res(): routine to produce default underflow result of a 	#
#	 	   scaled extended precision number; this is used by 	#
#		   fadd/fdiv/fmul/etc. emulation routines.		#
# 	unf_res4(): same as above but for fsglmul/fsgldiv which use	#
#		    single round prec and extended prec mode.		#
#									#
# XREF ****************************************************************	#
#	_denorm() - denormalize according to scale factor		#
# 	_round() - round denormalized number according to rnd prec	#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to extended precison operand			#
#	d0 = scale factor						#
#	d1 = rounding precision/mode					#
#									#
# OUTPUT **************************************************************	#
#	a0 = pointer to default underflow result in extended precision	#
#	d0.b = result FPSR_cc which caller may or may not want to save	#
#									#
# ALGORITHM ***********************************************************	#
# 	Convert the input operand to "internal format" which means the	#
# exponent is extended to 16 bits and the sign is stored in the unused	#
# portion of the extended precison operand. Denormalize the number	#
# according to the scale factor passed in d0. Then, round the 		#
# denormalized result.							#
# 	Set the FPSR_exc bits as appropriate but return the cc bits in	#
# d0 in case the caller doesn't want to save them (as is the case for	#
# fmove out).								#
# 	unf_res4() for fsglmul/fsgldiv forces the denorm to extended	#
# precision and the rounding mode to single.				#
#									#
#########################################################################
	global		unf_res
unf_res:
	mov.l		%d1, -(%sp)		# save rnd prec,mode on stack

	btst		&0x7, FTEMP_EX(%a0)	# make "internal" format
	sne		FTEMP_SGN(%a0)

	mov.w		FTEMP_EX(%a0), %d1	# extract exponent
	and.w		&0x7fff, %d1
	sub.w		%d0, %d1
	mov.w		%d1, FTEMP_EX(%a0)	# insert 16 bit exponent

	mov.l		%a0, -(%sp)		# save operand ptr during calls

	mov.l		0x4(%sp),%d0		# pass rnd prec.
	andi.w		&0x00c0,%d0
	lsr.w		&0x4,%d0
	bsr.l		_denorm			# denorm result

	mov.l		(%sp),%a0
	mov.w		0x6(%sp),%d1		# load prec:mode into %d1
	andi.w		&0xc0,%d1		# extract rnd prec
	lsr.w		&0x4,%d1
	swap		%d1
	mov.w		0x6(%sp),%d1
	andi.w		&0x30,%d1
	lsr.w		&0x4,%d1
	bsr.l		_round			# round the denorm

	mov.l		(%sp)+, %a0

# result is now rounded properly. convert back to normal format
	bclr		&0x7, FTEMP_EX(%a0)	# clear sgn first; may have residue
	tst.b		FTEMP_SGN(%a0)		# is "internal result" sign set?
	beq.b		unf_res_chkifzero	# no; result is positive
	bset		&0x7, FTEMP_EX(%a0)	# set result sgn
	clr.b		FTEMP_SGN(%a0)		# clear temp sign

# the number may have become zero after rounding. set ccodes accordingly.
unf_res_chkifzero:
	clr.l		%d0
	tst.l		FTEMP_HI(%a0)		# is value now a zero?
	bne.b		unf_res_cont		# no
	tst.l		FTEMP_LO(%a0)
	bne.b		unf_res_cont		# no
#	bset		&z_bit, FPSR_CC(%a6)	# yes; set zero ccode bit
	bset		&z_bit, %d0		# yes; set zero ccode bit

unf_res_cont:

#
# can inex1 also be set along with unfl and inex2???
#
# we know that underflow has occurred. aunfl should be set if INEX2 is also set.
#
	btst		&inex2_bit, FPSR_EXCEPT(%a6) # is INEX2 set?
	beq.b		unf_res_end		# no
	bset		&aunfl_bit, FPSR_AEXCEPT(%a6) # yes; set aunfl

unf_res_end:
	add.l		&0x4, %sp		# clear stack
	rts

# unf_res() for fsglmul() and fsgldiv().
	global		unf_res4
unf_res4:
	mov.l		%d1,-(%sp)		# save rnd prec,mode on stack

	btst		&0x7,FTEMP_EX(%a0)	# make "internal" format
	sne		FTEMP_SGN(%a0)

	mov.w		FTEMP_EX(%a0),%d1	# extract exponent
	and.w		&0x7fff,%d1
	sub.w		%d0,%d1
	mov.w		%d1,FTEMP_EX(%a0)	# insert 16 bit exponent

	mov.l		%a0,-(%sp)		# save operand ptr during calls

	clr.l		%d0			# force rnd prec = ext
	bsr.l		_denorm			# denorm result

	mov.l		(%sp),%a0
	mov.w		&s_mode,%d1		# force rnd prec = sgl
	swap		%d1
	mov.w		0x6(%sp),%d1		# load rnd mode
	andi.w		&0x30,%d1		# extract rnd prec
	lsr.w		&0x4,%d1
	bsr.l		_round			# round the denorm

	mov.l		(%sp)+,%a0

# result is now rounded properly. convert back to normal format
	bclr		&0x7,FTEMP_EX(%a0)	# clear sgn first; may have residue
	tst.b		FTEMP_SGN(%a0)		# is "internal result" sign set?
	beq.b		unf_res4_chkifzero	# no; result is positive
	bset		&0x7,FTEMP_EX(%a0)	# set result sgn
	clr.b		FTEMP_SGN(%a0)		# clear temp sign

# the number may have become zero after rounding. set ccodes accordingly.
unf_res4_chkifzero:
	clr.l		%d0
	tst.l		FTEMP_HI(%a0)		# is value now a zero?
	bne.b		unf_res4_cont		# no
	tst.l		FTEMP_LO(%a0)
	bne.b		unf_res4_cont		# no
#	bset		&z_bit,FPSR_CC(%a6)	# yes; set zero ccode bit
	bset		&z_bit,%d0		# yes; set zero ccode bit

unf_res4_cont:

#
# can inex1 also be set along with unfl and inex2???
#
# we know that underflow has occurred. aunfl should be set if INEX2 is also set.
#
	btst		&inex2_bit,FPSR_EXCEPT(%a6) # is INEX2 set?
	beq.b		unf_res4_end		# no
	bset		&aunfl_bit,FPSR_AEXCEPT(%a6) # yes; set aunfl

unf_res4_end:
	add.l		&0x4,%sp		# clear stack
	rts

#########################################################################
# XDEF ****************************************************************	#
#	ovf_res(): routine to produce the default overflow result of	#
#		   an overflowing number.				#
#	ovf_res2(): same as above but the rnd mode/prec are passed	#
#		    differently.					#
#									#
# XREF ****************************************************************	#
#	none								#
#									#
# INPUT ***************************************************************	#
#	d1.b 	= '-1' => (-); '0' => (+)				#
#   ovf_res():								#
#	d0 	= rnd mode/prec						#
#   ovf_res2():								#
#	hi(d0) 	= rnd prec						#
#	lo(d0)	= rnd mode						#
#									#
# OUTPUT **************************************************************	#
#	a0   	= points to extended precision result			#
#	d0.b 	= condition code bits					#
#									#
# ALGORITHM ***********************************************************	#
#	The default overflow result can be determined by the sign of	#
# the result and the rounding mode/prec in effect. These bits are	#
# concatenated together to create an index into the default result 	#
# table. A pointer to the correct result is returned in a0. The		#
# resulting condition codes are returned in d0 in case the caller 	#
# doesn't want FPSR_cc altered (as is the case for fmove out).		#
#									#
#########################################################################

	global		ovf_res
ovf_res:
	andi.w		&0x10,%d1		# keep result sign
	lsr.b		&0x4,%d0		# shift prec/mode
	or.b		%d0,%d1			# concat the two
	mov.w		%d1,%d0			# make a copy
	lsl.b		&0x1,%d1		# multiply d1 by 2
	bra.b		ovf_res_load

	global		ovf_res2
ovf_res2:
	and.w		&0x10, %d1		# keep result sign
	or.b		%d0, %d1		# insert rnd mode
	swap		%d0
	or.b		%d0, %d1		# insert rnd prec
	mov.w		%d1, %d0		# make a copy
	lsl.b		&0x1, %d1		# shift left by 1

#
# use the rounding mode, precision, and result sign as in index into the
# two tables below to fetch the default result and the result ccodes.
#
ovf_res_load:
	mov.b		(tbl_ovfl_cc.b,%pc,%d0.w*1), %d0 # fetch result ccodes
	lea		(tbl_ovfl_result.b,%pc,%d1.w*8), %a0 # return result ptr
	
	rts

tbl_ovfl_cc:
	byte		0x2, 0x0, 0x0, 0x2
	byte		0x2, 0x0, 0x0, 0x2
	byte		0x2, 0x0, 0x0, 0x2
	byte		0x0, 0x0, 0x0, 0x0
	byte		0x2+0x8, 0x8, 0x2+0x8, 0x8
	byte		0x2+0x8, 0x8, 0x2+0x8, 0x8
	byte		0x2+0x8, 0x8, 0x2+0x8, 0x8

tbl_ovfl_result:
	long		0x7fff0000,0x00000000,0x00000000,0x00000000 # +INF; RN
	long		0x7ffe0000,0xffffffff,0xffffffff,0x00000000 # +EXT; RZ
	long		0x7ffe0000,0xffffffff,0xffffffff,0x00000000 # +EXT; RM
	long		0x7fff0000,0x00000000,0x00000000,0x00000000 # +INF; RP

	long		0x7fff0000,0x00000000,0x00000000,0x00000000 # +INF; RN
	long		0x407e0000,0xffffff00,0x00000000,0x00000000 # +SGL; RZ
	long		0x407e0000,0xffffff00,0x00000000,0x00000000 # +SGL; RM
	long		0x7fff0000,0x00000000,0x00000000,0x00000000 # +INF; RP

	long		0x7fff0000,0x00000000,0x00000000,0x00000000 # +INF; RN
	long		0x43fe0000,0xffffffff,0xfffff800,0x00000000 # +DBL; RZ
	long		0x43fe0000,0xffffffff,0xfffff800,0x00000000 # +DBL; RM
	long		0x7fff0000,0x00000000,0x00000000,0x00000000 # +INF; RP

	long		0x00000000,0x00000000,0x00000000,0x00000000
	long		0x00000000,0x00000000,0x00000000,0x00000000
	long		0x00000000,0x00000000,0x00000000,0x00000000
	long		0x00000000,0x00000000,0x00000000,0x00000000

	long		0xffff0000,0x00000000,0x00000000,0x00000000 # -INF; RN
	long		0xfffe0000,0xffffffff,0xffffffff,0x00000000 # -EXT; RZ
	long		0xffff0000,0x00000000,0x00000000,0x00000000 # -INF; RM
	long		0xfffe0000,0xffffffff,0xffffffff,0x00000000 # -EXT; RP

	long		0xffff0000,0x00000000,0x00000000,0x00000000 # -INF; RN
	long		0xc07e0000,0xffffff00,0x00000000,0x00000000 # -SGL; RZ
	long		0xffff0000,0x00000000,0x00000000,0x00000000 # -INF; RM
	long		0xc07e0000,0xffffff00,0x00000000,0x00000000 # -SGL; RP

	long		0xffff0000,0x00000000,0x00000000,0x00000000 # -INF; RN
	long		0xc3fe0000,0xffffffff,0xfffff800,0x00000000 # -DBL; RZ
	long		0xffff0000,0x00000000,0x00000000,0x00000000 # -INF; RM
	long		0xc3fe0000,0xffffffff,0xfffff800,0x00000000 # -DBL; RP

#########################################################################
# XDEF ****************************************************************	#
#	get_packed(): fetch a packed operand from memory and then	#
#		      convert it to a floating-point binary number.	#
#									#
# XREF ****************************************************************	#
#	_dcalc_ea() - calculate the correct <ea>			#
#	_mem_read() - fetch the packed operand from memory		#
#	facc_in_x() - the fetch failed so jump to special exit code	#
#	decbin()    - convert packed to binary extended precision	#
#									#
# INPUT ***************************************************************	#
#	None								#
# 									#
# OUTPUT **************************************************************	#
#	If no failure on _mem_read():					#
# 	FP_SRC(a6) = packed operand now as a binary FP number		#
#									#
# ALGORITHM ***********************************************************	#
#	Get the correct <ea> whihc is the value on the exception stack 	#
# frame w/ maybe a correction factor if the <ea> is -(an) or (an)+.	#
# Then, fetch the operand from memory. If the fetch fails, exit		#
# through facc_in_x().							#
#	If the packed operand is a ZERO,NAN, or INF, convert it to	#
# its binary representation here. Else, call decbin() which will 	#
# convert the packed value to an extended precision binary value.	#
#									#
#########################################################################

# the stacked <ea> for packed is correct except for -(An).
# the base reg must be updated for both -(An) and (An)+.
	global		get_packed
get_packed:
	mov.l		&0xc,%d0		# packed is 12 bytes
	bsr.l		_dcalc_ea		# fetch <ea>; correct An

	lea		FP_SRC(%a6),%a1		# pass: ptr to super dst
	mov.l		&0xc,%d0		# pass: 12 bytes
	bsr.l		_dmem_read		# read packed operand

	tst.l		%d1			# did dfetch fail?
	bne.l		facc_in_x		# yes

# The packed operand is an INF or a NAN if the exponent field is all ones.
	bfextu		FP_SRC(%a6){&1:&15},%d0	# get exp
	cmpi.w		%d0,&0x7fff		# INF or NAN?
	bne.b		gp_try_zero		# no
	rts					# operand is an INF or NAN

# The packed operand is a zero if the mantissa is all zero, else it's
# a normal packed op.
gp_try_zero:
	mov.b		3+FP_SRC(%a6),%d0	# get byte 4
	andi.b		&0x0f,%d0		# clear all but last nybble
	bne.b		gp_not_spec		# not a zero
	tst.l		FP_SRC_HI(%a6)		# is lw 2 zero?
	bne.b		gp_not_spec		# not a zero
	tst.l		FP_SRC_LO(%a6)		# is lw 3 zero?
	bne.b		gp_not_spec		# not a zero
	rts					# operand is a ZERO
gp_not_spec:
	lea		FP_SRC(%a6),%a0		# pass: ptr to packed op
	bsr.l		decbin			# convert to extended
	fmovm.x		&0x80,FP_SRC(%a6)	# make this the srcop
	rts

#########################################################################
# decbin(): Converts normalized packed bcd value pointed to by register	#
#	    a0 to extended-precision value in fp0.			#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to normalized packed bcd value			#
#									#
# OUTPUT **************************************************************	#
#	fp0 = exact fp representation of the packed bcd value.		#
#									#
# ALGORITHM ***********************************************************	#
#	Expected is a normal bcd (i.e. non-exceptional; all inf, zero,	#
#	and NaN operands are dispatched without entering this routine)	#
#	value in 68881/882 format at location (a0).			#
#									#
#	A1. Convert the bcd exponent to binary by successive adds and 	#
#	muls. Set the sign according to SE. Subtract 16 to compensate	#
#	for the mantissa which is to be interpreted as 17 integer	#
#	digits, rather than 1 integer and 16 fraction digits.		#
#	Note: this operation can never overflow.			#
#									#
#	A2. Convert the bcd mantissa to binary by successive		#
#	adds and muls in FP0. Set the sign according to SM.		#
#	The mantissa digits will be converted with the decimal point	#
#	assumed following the least-significant digit.			#
#	Note: this operation can never overflow.			#
#									#
#	A3. Count the number of leading/trailing zeros in the		#
#	bcd string.  If SE is positive, count the leading zeros;	#
#	if negative, count the trailing zeros.  Set the adjusted	#
#	exponent equal to the exponent from A1 and the zero count	#
#	added if SM = 1 and subtracted if SM = 0.  Scale the		#
#	mantissa the equivalent of forcing in the bcd value:		#
#									#
#	SM = 0	a non-zero digit in the integer position		#
#	SM = 1	a non-zero digit in Mant0, lsd of the fraction		#
#									#
#	this will insure that any value, regardless of its		#
#	representation (ex. 0.1E2, 1E1, 10E0, 100E-1), is converted	#
#	consistently.							#
#									#
#	A4. Calculate the factor 10^exp in FP1 using a table of		#
#	10^(2^n) values.  To reduce the error in forming factors	#
#	greater than 10^27, a directed rounding scheme is used with	#
#	tables rounded to RN, RM, and RP, according to the table	#
#	in the comments of the pwrten section.				#
#									#
#	A5. Form the final binary number by scaling the mantissa by	#
#	the exponent factor.  This is done by multiplying the		#
#	mantissa in FP0 by the factor in FP1 if the adjusted		#
#	exponent sign is positive, and dividing FP0 by FP1 if		#
#	it is negative.							#
#									#
#	Clean up and return. Check if the final mul or div was inexact.	#
#	If so, set INEX1 in USER_FPSR.					#
#									#
#########################################################################

#
#	PTENRN, PTENRM, and PTENRP are arrays of powers of 10 rounded
#	to nearest, minus, and plus, respectively.  The tables include
#	10**{1,2,4,8,16,32,64,128,256,512,1024,2048,4096}.  No rounding
#	is required until the power is greater than 27, however, all
#	tables include the first 5 for ease of indexing.
#
RTABLE:
	byte		0,0,0,0
	byte		2,3,2,3
	byte		2,3,3,2
	byte		3,2,2,3

	set		FNIBS,7
	set		FSTRT,0

	set		ESTRT,4
	set		EDIGITS,2

	global		decbin
decbin:
	mov.l		0x0(%a0),FP_SCR0_EX(%a6) # make a copy of input 
	mov.l		0x4(%a0),FP_SCR0_HI(%a6) # so we don't alter it
	mov.l		0x8(%a0),FP_SCR0_LO(%a6)

	lea		FP_SCR0(%a6),%a0

	movm.l		&0x3c00,-(%sp)		# save d2-d5
	fmovm.x		&0x1,-(%sp)		# save fp1
#
# Calculate exponent:
#  1. Copy bcd value in memory for use as a working copy.
#  2. Calculate absolute value of exponent in d1 by mul and add.
#  3. Correct for exponent sign.
#  4. Subtract 16 to compensate for interpreting the mant as all integer digits.
#     (i.e., all digits assumed left of the decimal point.)
#
# Register usage:
#
#  calc_e:
#	(*)  d0: temp digit storage
#	(*)  d1: accumulator for binary exponent
#	(*)  d2: digit count
#	(*)  d3: offset pointer
#	( )  d4: first word of bcd
#	( )  a0: pointer to working bcd value
#	( )  a6: pointer to original bcd value
#	(*)  FP_SCR1: working copy of original bcd value
#	(*)  L_SCR1: copy of original exponent word
#
calc_e:
	mov.l		&EDIGITS,%d2		# # of nibbles (digits) in fraction part
	mov.l		&ESTRT,%d3		# counter to pick up digits
	mov.l		(%a0),%d4		# get first word of bcd
	clr.l		%d1			# zero d1 for accumulator
e_gd:
	mulu.l		&0xa,%d1		# mul partial product by one digit place
	bfextu		%d4{%d3:&4},%d0		# get the digit and zero extend into d0
	add.l		%d0,%d1			# d1 = d1 + d0
	addq.b		&4,%d3			# advance d3 to the next digit
	dbf.w		%d2,e_gd		# if we have used all 3 digits, exit loop
	btst		&30,%d4			# get SE
	beq.b		e_pos			# don't negate if pos
	neg.l		%d1			# negate before subtracting
e_pos:
	sub.l		&16,%d1			# sub to compensate for shift of mant
	bge.b		e_save			# if still pos, do not neg
	neg.l		%d1			# now negative, make pos and set SE
	or.l		&0x40000000,%d4		# set SE in d4,
	or.l		&0x40000000,(%a0)	# and in working bcd
e_save:
	mov.l		%d1,-(%sp)		# save exp on stack
#
#
# Calculate mantissa:
#  1. Calculate absolute value of mantissa in fp0 by mul and add.
#  2. Correct for mantissa sign.
#     (i.e., all digits assumed left of the decimal point.)
#
# Register usage:
#
#  calc_m:
#	(*)  d0: temp digit storage
#	(*)  d1: lword counter
#	(*)  d2: digit count
#	(*)  d3: offset pointer
#	( )  d4: words 2 and 3 of bcd
#	( )  a0: pointer to working bcd value
#	( )  a6: pointer to original bcd value
#	(*) fp0: mantissa accumulator
#	( )  FP_SCR1: working copy of original bcd value
#	( )  L_SCR1: copy of original exponent word
#
calc_m:
	mov.l		&1,%d1			# word counter, init to 1
	fmov.s		&0x00000000,%fp0	# accumulator
#
#
#  Since the packed number has a long word between the first & second parts,
#  get the integer digit then skip down & get the rest of the
#  mantissa.  We will unroll the loop once.
#
	bfextu		(%a0){&28:&4},%d0	# integer part is ls digit in long word
	fadd.b		%d0,%fp0		# add digit to sum in fp0
#
#
#  Get the rest of the mantissa.
#
loadlw:
	mov.l		(%a0,%d1.L*4),%d4	# load mantissa lonqword into d4
	mov.l		&FSTRT,%d3		# counter to pick up digits
	mov.l		&FNIBS,%d2		# reset number of digits per a0 ptr
md2b:
	fmul.s		&0x41200000,%fp0	# fp0 = fp0 * 10
	bfextu		%d4{%d3:&4},%d0		# get the digit and zero extend
	fadd.b		%d0,%fp0		# fp0 = fp0 + digit
#
#
#  If all the digits (8) in that long word have been converted (d2=0),
#  then inc d1 (=2) to point to the next long word and reset d3 to 0
#  to initialize the digit offset, and set d2 to 7 for the digit count;
#  else continue with this long word.
#
	addq.b		&4,%d3			# advance d3 to the next digit
	dbf.w		%d2,md2b		# check for last digit in this lw
nextlw:
	addq.l		&1,%d1			# inc lw pointer in mantissa
	cmp.l		%d1,&2			# test for last lw
	ble.b		loadlw			# if not, get last one
#
#  Check the sign of the mant and make the value in fp0 the same sign.
#
m_sign:
	btst		&31,(%a0)		# test sign of the mantissa
	beq.b		ap_st_z			# if clear, go to append/strip zeros
	fneg.x		%fp0			# if set, negate fp0
#
# Append/strip zeros:
#
#  For adjusted exponents which have an absolute value greater than 27*,
#  this routine calculates the amount needed to normalize the mantissa
#  for the adjusted exponent.  That number is subtracted from the exp
#  if the exp was positive, and added if it was negative.  The purpose
#  of this is to reduce the value of the exponent and the possibility
#  of error in calculation of pwrten.
#
#  1. Branch on the sign of the adjusted exponent.
#  2p.(positive exp)
#   2. Check M16 and the digits in lwords 2 and 3 in decending order.
#   3. Add one for each zero encountered until a non-zero digit.
#   4. Subtract the count from the exp.
#   5. Check if the exp has crossed zero in #3 above; make the exp abs
#	   and set SE.
#	6. Multiply the mantissa by 10**count.
#  2n.(negative exp)
#   2. Check the digits in lwords 3 and 2 in decending order.
#   3. Add one for each zero encountered until a non-zero digit.
#   4. Add the count to the exp.
#   5. Check if the exp has crossed zero in #3 above; clear SE.
#   6. Divide the mantissa by 10**count.
#
#  *Why 27?  If the adjusted exponent is within -28 < expA < 28, than
#   any adjustment due to append/strip zeros will drive the resultane
#   exponent towards zero.  Since all pwrten constants with a power
#   of 27 or less are exact, there is no need to use this routine to
#   attempt to lessen the resultant exponent.
#
# Register usage:
#
#  ap_st_z:
#	(*)  d0: temp digit storage
#	(*)  d1: zero count
#	(*)  d2: digit count
#	(*)  d3: offset pointer
#	( )  d4: first word of bcd
#	(*)  d5: lword counter
#	( )  a0: pointer to working bcd value
#	( )  FP_SCR1: working copy of original bcd value
#	( )  L_SCR1: copy of original exponent word
#
#
# First check the absolute value of the exponent to see if this
# routine is necessary.  If so, then check the sign of the exponent
# and do append (+) or strip (-) zeros accordingly.
# This section handles a positive adjusted exponent.
#
ap_st_z:
	mov.l		(%sp),%d1		# load expA for range test
	cmp.l		%d1,&27			# test is with 27
	ble.w		pwrten			# if abs(expA) <28, skip ap/st zeros
	btst		&30,(%a0)		# check sign of exp
	bne.b		ap_st_n			# if neg, go to neg side
	clr.l		%d1			# zero count reg
	mov.l		(%a0),%d4		# load lword 1 to d4
	bfextu		%d4{&28:&4},%d0		# get M16 in d0
	bne.b		ap_p_fx			# if M16 is non-zero, go fix exp
	addq.l		&1,%d1			# inc zero count
	mov.l		&1,%d5			# init lword counter
	mov.l		(%a0,%d5.L*4),%d4	# get lword 2 to d4
	bne.b		ap_p_cl			# if lw 2 is zero, skip it
	addq.l		&8,%d1			# and inc count by 8
	addq.l		&1,%d5			# inc lword counter
	mov.l		(%a0,%d5.L*4),%d4	# get lword 3 to d4
ap_p_cl:
	clr.l		%d3			# init offset reg
	mov.l		&7,%d2			# init digit counter
ap_p_gd:
	bfextu		%d4{%d3:&4},%d0		# get digit
	bne.b		ap_p_fx			# if non-zero, go to fix exp
	addq.l		&4,%d3			# point to next digit
	addq.l		&1,%d1			# inc digit counter
	dbf.w		%d2,ap_p_gd		# get next digit
ap_p_fx:
	mov.l		%d1,%d0			# copy counter to d2
	mov.l		(%sp),%d1		# get adjusted exp from memory
	sub.l		%d0,%d1			# subtract count from exp
	bge.b		ap_p_fm			# if still pos, go to pwrten
	neg.l		%d1			# now its neg; get abs
	mov.l		(%a0),%d4		# load lword 1 to d4
	or.l		&0x40000000,%d4		# and set SE in d4
	or.l		&0x40000000,(%a0)	# and in memory
#
# Calculate the mantissa multiplier to compensate for the striping of
# zeros from the mantissa.
#
ap_p_fm:
	lea.l		PTENRN(%pc),%a1		# get address of power-of-ten table
	clr.l		%d3			# init table index
	fmov.s		&0x3f800000,%fp1	# init fp1 to 1
	mov.l		&3,%d2			# init d2 to count bits in counter
ap_p_el:
	asr.l		&1,%d0			# shift lsb into carry
	bcc.b		ap_p_en			# if 1, mul fp1 by pwrten factor
	fmul.x		(%a1,%d3),%fp1		# mul by 10**(d3_bit_no)
ap_p_en:
	add.l		&12,%d3			# inc d3 to next rtable entry
	tst.l		%d0			# check if d0 is zero
	bne.b		ap_p_el			# if not, get next bit
	fmul.x		%fp1,%fp0		# mul mantissa by 10**(no_bits_shifted)
	bra.b		pwrten			# go calc pwrten
#
# This section handles a negative adjusted exponent.
#
ap_st_n:
	clr.l		%d1			# clr counter
	mov.l		&2,%d5			# set up d5 to point to lword 3
	mov.l		(%a0,%d5.L*4),%d4	# get lword 3
	bne.b		ap_n_cl			# if not zero, check digits
	sub.l		&1,%d5			# dec d5 to point to lword 2
	addq.l		&8,%d1			# inc counter by 8
	mov.l		(%a0,%d5.L*4),%d4	# get lword 2
ap_n_cl:
	mov.l		&28,%d3			# point to last digit
	mov.l		&7,%d2			# init digit counter
ap_n_gd:
	bfextu		%d4{%d3:&4},%d0		# get digit
	bne.b		ap_n_fx			# if non-zero, go to exp fix
	subq.l		&4,%d3			# point to previous digit
	addq.l		&1,%d1			# inc digit counter
	dbf.w		%d2,ap_n_gd		# get next digit
ap_n_fx:
	mov.l		%d1,%d0			# copy counter to d0
	mov.l		(%sp),%d1		# get adjusted exp from memory
	sub.l		%d0,%d1			# subtract count from exp
	bgt.b		ap_n_fm			# if still pos, go fix mantissa
	neg.l		%d1			# take abs of exp and clr SE
	mov.l		(%a0),%d4		# load lword 1 to d4
	and.l		&0xbfffffff,%d4		# and clr SE in d4
	and.l		&0xbfffffff,(%a0)	# and in memory
#
# Calculate the mantissa multiplier to compensate for the appending of
# zeros to the mantissa.
#
ap_n_fm:
	lea.l		PTENRN(%pc),%a1		# get address of power-of-ten table
	clr.l		%d3			# init table index
	fmov.s		&0x3f800000,%fp1	# init fp1 to 1
	mov.l		&3,%d2			# init d2 to count bits in counter
ap_n_el:
	asr.l		&1,%d0			# shift lsb into carry
	bcc.b		ap_n_en			# if 1, mul fp1 by pwrten factor
	fmul.x		(%a1,%d3),%fp1		# mul by 10**(d3_bit_no)
ap_n_en:
	add.l		&12,%d3			# inc d3 to next rtable entry
	tst.l		%d0			# check if d0 is zero
	bne.b		ap_n_el			# if not, get next bit
	fdiv.x		%fp1,%fp0		# div mantissa by 10**(no_bits_shifted)
#
#
# Calculate power-of-ten factor from adjusted and shifted exponent.
#
# Register usage:
#
#  pwrten:
#	(*)  d0: temp
#	( )  d1: exponent
#	(*)  d2: {FPCR[6:5],SM,SE} as index in RTABLE; temp
#	(*)  d3: FPCR work copy
#	( )  d4: first word of bcd
#	(*)  a1: RTABLE pointer
#  calc_p:
#	(*)  d0: temp
#	( )  d1: exponent
#	(*)  d3: PWRTxx table index
#	( )  a0: pointer to working copy of bcd
#	(*)  a1: PWRTxx pointer
#	(*) fp1: power-of-ten accumulator
#
# Pwrten calculates the exponent factor in the selected rounding mode
# according to the following table:
#	
#	Sign of Mant  Sign of Exp  Rounding Mode  PWRTEN Rounding Mode
#
#	ANY	  ANY	RN	RN
#
#	 +	   +	RP	RP
#	 -	   +	RP	RM
#	 +	   -	RP	RM
#	 -	   -	RP	RP
#
#	 +	   +	RM	RM
#	 -	   +	RM	RP
#	 +	   -	RM	RP
#	 -	   -	RM	RM
#
#	 +	   +	RZ	RM
#	 -	   +	RZ	RM
#	 +	   -	RZ	RP
#	 -	   -	RZ	RP
#
#
pwrten:
	mov.l		USER_FPCR(%a6),%d3	# get user's FPCR
	bfextu		%d3{&26:&2},%d2		# isolate rounding mode bits
	mov.l		(%a0),%d4		# reload 1st bcd word to d4
	asl.l		&2,%d2			# format d2 to be
	bfextu		%d4{&0:&2},%d0		# {FPCR[6],FPCR[5],SM,SE}
	add.l		%d0,%d2			# in d2 as index into RTABLE
	lea.l		RTABLE(%pc),%a1		# load rtable base
	mov.b		(%a1,%d2),%d0		# load new rounding bits from table
	clr.l		%d3			# clear d3 to force no exc and extended
	bfins		%d0,%d3{&26:&2}		# stuff new rounding bits in FPCR
	fmov.l		%d3,%fpcr		# write new FPCR
	asr.l		&1,%d0			# write correct PTENxx table
	bcc.b		not_rp			# to a1
	lea.l		PTENRP(%pc),%a1		# it is RP
	bra.b		calc_p			# go to init section
not_rp:
	asr.l		&1,%d0			# keep checking
	bcc.b		not_rm
	lea.l		PTENRM(%pc),%a1		# it is RM
	bra.b		calc_p			# go to init section
not_rm:
	lea.l		PTENRN(%pc),%a1		# it is RN
calc_p:
	mov.l		%d1,%d0			# copy exp to d0;use d0
	bpl.b		no_neg			# if exp is negative,
	neg.l		%d0			# invert it
	or.l		&0x40000000,(%a0)	# and set SE bit
no_neg:
	clr.l		%d3			# table index
	fmov.s		&0x3f800000,%fp1	# init fp1 to 1
e_loop:
	asr.l		&1,%d0			# shift next bit into carry
	bcc.b		e_next			# if zero, skip the mul
	fmul.x		(%a1,%d3),%fp1		# mul by 10**(d3_bit_no)
e_next:
	add.l		&12,%d3			# inc d3 to next rtable entry
	tst.l		%d0			# check if d0 is zero
	bne.b		e_loop			# not zero, continue shifting
#
#
#  Check the sign of the adjusted exp and make the value in fp0 the
#  same sign. If the exp was pos then multiply fp1*fp0;
#  else divide fp0/fp1.
#
# Register Usage:
#  norm:
#	( )  a0: pointer to working bcd value
#	(*) fp0: mantissa accumulator
#	( ) fp1: scaling factor - 10**(abs(exp))
#
pnorm:
	btst		&30,(%a0)		# test the sign of the exponent
	beq.b		mul			# if clear, go to multiply
div:
	fdiv.x		%fp1,%fp0		# exp is negative, so divide mant by exp
	bra.b		end_dec
mul:
	fmul.x		%fp1,%fp0		# exp is positive, so multiply by exp
#
#
# Clean up and return with result in fp0.
#
# If the final mul/div in decbin incurred an inex exception,
# it will be inex2, but will be reported as inex1 by get_op.
#
end_dec:
	fmov.l		%fpsr,%d0		# get status register	
	bclr		&inex2_bit+8,%d0	# test for inex2 and clear it
	beq.b		no_exc			# skip this if no exc
	ori.w		&inx1a_mask,2+USER_FPSR(%a6) # set INEX1/AINEX
no_exc:
	add.l		&0x4,%sp		# clear 1 lw param
	fmovm.x		(%sp)+,&0x40		# restore fp1
	movm.l		(%sp)+,&0x3c		# restore d2-d5
	fmov.l		&0x0,%fpcr
	fmov.l		&0x0,%fpsr
	rts

#########################################################################
# bindec(): Converts an input in extended precision format to bcd format#
#									#
# INPUT ***************************************************************	#
#	a0 = pointer to the input extended precision value in memory.	#
#	     the input may be either normalized, unnormalized, or 	#
#	     denormalized.						#
#	d0 = contains the k-factor sign-extended to 32-bits. 		#
#									#
# OUTPUT **************************************************************	#
#	FP_SCR0(a6) = bcd format result on the stack.			#
#									#
# ALGORITHM ***********************************************************	#
#									#
#	A1.	Set RM and size ext;  Set SIGMA = sign of input.  	#
#		The k-factor is saved for use in d7. Clear the		#
#		BINDEC_FLG for separating normalized/denormalized	#
#		input.  If input is unnormalized or denormalized,	#
#		normalize it.						#
#									#
#	A2.	Set X = abs(input).					#
#									#
#	A3.	Compute ILOG.						#
#		ILOG is the log base 10 of the input value.  It is	#
#		approximated by adding e + 0.f when the original 	#
#		value is viewed as 2^^e * 1.f in extended precision.  	#
#		This value is stored in d6.				#
#									#
#	A4.	Clr INEX bit.						#
#		The operation in A3 above may have set INEX2.  		#
#									#
#	A5.	Set ICTR = 0;						#
#		ICTR is a flag used in A13.  It must be set before the 	#
#		loop entry A6.						#
#									#
#	A6.	Calculate LEN.						#
#		LEN is the number of digits to be displayed.  The	#
#		k-factor can dictate either the total number of digits,	#
#		if it is a positive number, or the number of digits	#
#		after the decimal point which are to be included as	#
#		significant.  See the 68882 manual for examples.	#
#		If LEN is computed to be greater than 17, set OPERR in	#
#		USER_FPSR.  LEN is stored in d4.			#
#									#
#	A7.	Calculate SCALE.					#
#		SCALE is equal to 10^ISCALE, where ISCALE is the number	#
#		of decimal places needed to insure LEN integer digits	#
#		in the output before conversion to bcd. LAMBDA is the	#
#		sign of ISCALE, used in A9. Fp1 contains		#
#		10^^(abs(ISCALE)) using a rounding mode which is a	#
#		function of the original rounding mode and the signs	#
#		of ISCALE and X.  A table is given in the code.		#
#									#
#	A8.	Clr INEX; Force RZ.					#
#		The operation in A3 above may have set INEX2.  		#
#		RZ mode is forced for the scaling operation to insure	#
#		only one rounding error.  The grs bits are collected in #
#		the INEX flag for use in A10.				#
#									#
#	A9.	Scale X -> Y.						#
#		The mantissa is scaled to the desired number of		#
#		significant digits.  The excess digits are collected	#
#		in INEX2.						#
#									#
#	A10.	Or in INEX.						#
#		If INEX is set, round error occurred.  This is		#
#		compensated for by 'or-ing' in the INEX2 flag to	#
#		the lsb of Y.						#
#									#
#	A11.	Restore original FPCR; set size ext.			#
#		Perform FINT operation in the user's rounding mode.	#
#		Keep the size to extended.				#
#									#
#	A12.	Calculate YINT = FINT(Y) according to user's rounding	#
#		mode.  The FPSP routine sintd0 is used.  The output	#
#		is in fp0.						#
#									#
#	A13.	Check for LEN digits.					#
#		If the int operation results in more than LEN digits,	#
#		or less than LEN -1 digits, adjust ILOG and repeat from	#
#		A6.  This test occurs only on the first pass.  If the	#
#		result is exactly 10^LEN, decrement ILOG and divide	#
#		the mantissa by 10.					#
#									#
#	A14.	Convert the mantissa to bcd.				#
#		The binstr routine is used to convert the LEN digit 	#
#		mantissa to bcd in memory.  The input to binstr is	#
#		to be a fraction; i.e. (mantissa)/10^LEN and adjusted	#
#		such that the decimal point is to the left of bit 63.	#
#		The bcd digits are stored in the correct position in 	#
#		the final string area in memory.			#
#									#
#	A15.	Convert the exponent to bcd.				#
#		As in A14 above, the exp is converted to bcd and the	#
#		digits are stored in the final string.			#
#		Test the length of the final exponent string.  If the	#
#		length is 4, set operr.					#
#									#
#	A16.	Write sign bits to final string.			#
#									#
#########################################################################

set	BINDEC_FLG,	EXC_TEMP	# DENORM flag

# Constants in extended precision
PLOG2:
	long		0x3FFD0000,0x9A209A84,0xFBCFF798,0x00000000
PLOG2UP1:
	long		0x3FFD0000,0x9A209A84,0xFBCFF799,0x00000000

# Constants in single precision
FONE:
	long		0x3F800000,0x00000000,0x00000000,0x00000000
FTWO:
	long		0x40000000,0x00000000,0x00000000,0x00000000
FTEN:
	long		0x41200000,0x00000000,0x00000000,0x00000000
F4933:
	long		0x459A2800,0x00000000,0x00000000,0x00000000

RBDTBL:
	byte		0,0,0,0
	byte		3,3,2,2
	byte		3,2,2,3
	byte		2,3,3,2

#	Implementation Notes:
#
#	The registers are used as follows:
#
#		d0: scratch; LEN input to binstr
#		d1: scratch
#		d2: upper 32-bits of mantissa for binstr
#		d3: scratch;lower 32-bits of mantissa for binstr
#		d4: LEN
#      		d5: LAMBDA/ICTR
#		d6: ILOG
#		d7: k-factor
#		a0: ptr for original operand/final result
#		a1: scratch pointer
#		a2: pointer to FP_X; abs(original value) in ext
#		fp0: scratch
#		fp1: scratch
#		fp2: scratch
#		F_SCR1:
#		F_SCR2:
#		L_SCR1:
#		L_SCR2:

	global		bindec
bindec:
	movm.l		&0x3f20,-(%sp)	#  {%d2-%d7/%a2}
	fmovm.x		&0x7,-(%sp)	#  {%fp0-%fp2}

# A1. Set RM and size ext. Set SIGMA = sign input;
#     The k-factor is saved for use in d7.  Clear BINDEC_FLG for
#     separating  normalized/denormalized input.  If the input
#     is a denormalized number, set the BINDEC_FLG memory word
#     to signal denorm.  If the input is unnormalized, normalize
#     the input and test for denormalized result.  
#
	fmov.l		&rm_mode*0x10,%fpcr	# set RM and ext
	mov.l		(%a0),L_SCR2(%a6)	# save exponent for sign check
	mov.l		%d0,%d7		# move k-factor to d7

	clr.b		BINDEC_FLG(%a6)	# clr norm/denorm flag
	cmpi.b		STAG(%a6),&DENORM # is input a DENORM?
	bne.w		A2_str		# no; input is a NORM

#
# Normalize the denorm
#
un_de_norm:
	mov.w		(%a0),%d0
	and.w		&0x7fff,%d0	# strip sign of normalized exp
	mov.l		4(%a0),%d1
	mov.l		8(%a0),%d2
norm_loop:
	sub.w		&1,%d0
	lsl.l		&1,%d2
	roxl.l		&1,%d1
	tst.l		%d1
	bge.b		norm_loop
#
# Test if the normalized input is denormalized
#
	tst.w		%d0
	bgt.b		pos_exp		# if greater than zero, it is a norm
	st		BINDEC_FLG(%a6)	# set flag for denorm
pos_exp:
	and.w		&0x7fff,%d0	# strip sign of normalized exp
	mov.w		%d0,(%a0)
	mov.l		%d1,4(%a0)
	mov.l		%d2,8(%a0)

# A2. Set X = abs(input).
#
A2_str:
	mov.l		(%a0),FP_SCR1(%a6)	# move input to work space
	mov.l		4(%a0),FP_SCR1+4(%a6)	# move input to work space
	mov.l		8(%a0),FP_SCR1+8(%a6)	# move input to work space
	and.l		&0x7fffffff,FP_SCR1(%a6)	# create abs(X)

# A3. Compute ILOG.
#     ILOG is the log base 10 of the input value.  It is approx-
#     imated by adding e + 0.f when the original value is viewed
#     as 2^^e * 1.f in extended precision.  This value is stored
#     in d6.
#
# Register usage:
#	Input/Output
#	d0: k-factor/exponent
#	d2: x/x
#	d3: x/x
#	d4: x/x
#	d5: x/x
#	d6: x/ILOG
#	d7: k-factor/Unchanged
#	a0: ptr for original operand/final result
#	a1: x/x
#	a2: x/x
#	fp0: x/float(ILOG)
#	fp1: x/x
#	fp2: x/x
#	F_SCR1:x/x
#	F_SCR2:Abs(X)/Abs(X) with $3fff exponent
#	L_SCR1:x/x
#	L_SCR2:first word of X packed/Unchanged

	tst.b		BINDEC_FLG(%a6)	# check for denorm
	beq.b		A3_cont		# if clr, continue with norm
	mov.l		&-4933,%d6	# force ILOG = -4933
	bra.b		A4_str
A3_cont:
	mov.w		FP_SCR1(%a6),%d0	# move exp to d0
	mov.w		&0x3fff,FP_SCR1(%a6)	# replace exponent with 0x3fff
	fmov.x		FP_SCR1(%a6),%fp0	# now fp0 has 1.f
	sub.w		&0x3fff,%d0	# strip off bias
	fadd.w		%d0,%fp0	# add in exp
	fsub.s		FONE(%pc),%fp0	# subtract off 1.0
	fbge.w		pos_res		# if pos, branch 
	fmul.x		PLOG2UP1(%pc),%fp0	# if neg, mul by LOG2UP1
	fmov.l		%fp0,%d6	# put ILOG in d6 as a lword
	bra.b		A4_str		# go move out ILOG
pos_res:
	fmul.x		PLOG2(%pc),%fp0	# if pos, mul by LOG2
	fmov.l		%fp0,%d6	# put ILOG in d6 as a lword


# A4. Clr INEX bit.
#     The operation in A3 above may have set INEX2.  

A4_str:
	fmov.l		&0,%fpsr	# zero all of fpsr - nothing needed


# A5. Set ICTR = 0;
#     ICTR is a flag used in A13.  It must be set before the 
#     loop entry A6. The lower word of d5 is used for ICTR.

	clr.w		%d5		# clear ICTR

# A6. Calculate LEN.
#     LEN is the number of digits to be displayed.  The k-factor
#     can dictate either the total number of digits, if it is
#     a positive number, or the number of digits after the
#     original decimal point which are to be included as
#     significant.  See the 68882 manual for examples.
#     If LEN is computed to be greater than 17, set OPERR in
#     USER_FPSR.  LEN is stored in d4.
#
# Register usage:
#	Input/Output
#	d0: exponent/Unchanged
#	d2: x/x/scratch
#	d3: x/x
#	d4: exc picture/LEN
#	d5: ICTR/Unchanged
#	d6: ILOG/Unchanged
#	d7: k-factor/Unchanged
#	a0: ptr for original operand/final result
#	a1: x/x
#	a2: x/x
#	fp0: float(ILOG)/Unchanged
#	fp1: x/x
#	fp2: x/x
#	F_SCR1:x/x
#	F_SCR2:Abs(X) with $3fff exponent/Unchanged
#	L_SCR1:x/x
#	L_SCR2:first word of X packed/Unchanged

A6_str:
	tst.l		%d7		# branch on sign of k
	ble.b		k_neg		# if k <= 0, LEN = ILOG + 1 - k
	mov.l		%d7,%d4		# if k > 0, LEN = k
	bra.b		len_ck		# skip to LEN check
k_neg:
	mov.l		%d6,%d4		# first load ILOG to d4
	sub.l		%d7,%d4		# subtract off k
	addq.l		&1,%d4		# add in the 1
len_ck:
	tst.l		%d4		# LEN check: branch on sign of LEN
	ble.b		LEN_ng		# if neg, set LEN = 1
	cmp.l		%d4,&17		# test if LEN > 17
	ble.b		A7_str		# if not, forget it
	mov.l		&17,%d4		# set max LEN = 17
	tst.l		%d7		# if negative, never set OPERR
	ble.b		A7_str		# if positive, continue
	or.l		&opaop_mask,USER_FPSR(%a6)	# set OPERR & AIOP in USER_FPSR
	bra.b		A7_str		# finished here
LEN_ng:
	mov.l		&1,%d4		# min LEN is 1


# A7. Calculate SCALE.
#     SCALE is equal to 10^ISCALE, where ISCALE is the number
#     of decimal places needed to insure LEN integer digits
#     in the output before conversion to bcd. LAMBDA is the sign
#     of ISCALE, used in A9.  Fp1 contains 10^^(abs(ISCALE)) using
#     the rounding mode as given in the following table (see
#     Coonen, p. 7.23 as ref.; however, the SCALE variable is
#     of opposite sign in bindec.sa from Coonen).
#
#	Initial					USE
#	FPCR[6:5]	LAMBDA	SIGN(X)		FPCR[6:5]
#	----------------------------------------------
#	 RN	00	   0	   0		00/0	RN
#	 RN	00	   0	   1		00/0	RN
#	 RN	00	   1	   0		00/0	RN
#	 RN	00	   1	   1		00/0	RN
#	 RZ	01	   0	   0		11/3	RP
#	 RZ	01	   0	   1		11/3	RP
#	 RZ	01	   1	   0		10/2	RM
#	 RZ	01	   1	   1		10/2	RM
#	 RM	10	   0	   0		11/3	RP
#	 RM	10	   0	   1		10/2	RM
#	 RM	10	   1	   0		10/2	RM
#	 RM	10	   1	   1		11/3	RP
#	 RP	11	   0	   0		10/2	RM
#	 RP	11	   0	   1		11/3	RP
#	 RP	11	   1	   0		11/3	RP
#	 RP	11	   1	   1		10/2	RM
#
# Register usage:
#	Input/Output
#	d0: exponent/scratch - final is 0
#	d2: x/0 or 24 for A9
#	d3: x/scratch - offset ptr into PTENRM array
#	d4: LEN/Unchanged
#	d5: 0/ICTR:LAMBDA
#	d6: ILOG/ILOG or k if ((k<=0)&(ILOG<k))
#	d7: k-factor/Unchanged
#	a0: ptr for original operand/final result
#	a1: x/ptr to PTENRM array
#	a2: x/x
#	fp0: float(ILOG)/Unchanged
#	fp1: x/10^ISCALE
#	fp2: x/x
#	F_SCR1:x/x
#	F_SCR2:Abs(X) with $3fff exponent/Unchanged
#	L_SCR1:x/x
#	L_SCR2:first word of X packed/Unchanged

A7_str:
	tst.l		%d7		# test sign of k
	bgt.b		k_pos		# if pos and > 0, skip this
	cmp.l		%d7,%d6		# test k - ILOG
	blt.b		k_pos		# if ILOG >= k, skip this
	mov.l		%d7,%d6		# if ((k<0) & (ILOG < k)) ILOG = k
k_pos:
	mov.l		%d6,%d0		# calc ILOG + 1 - LEN in d0
	addq.l		&1,%d0		# add the 1
	sub.l		%d4,%d0		# sub off LEN
	swap		%d5		# use upper word of d5 for LAMBDA
	clr.w		%d5		# set it zero initially
	clr.w		%d2		# set up d2 for very small case
	tst.l		%d0		# test sign of ISCALE
	bge.b		iscale		# if pos, skip next inst
	addq.w		&1,%d5		# if neg, set LAMBDA true
	cmp.l		%d0,&0xffffecd4	# test iscale <= -4908
	bgt.b		no_inf		# if false, skip rest
	add.l		&24,%d0		# add in 24 to iscale
	mov.l		&24,%d2		# put 24 in d2 for A9
no_inf:
	neg.l		%d0		# and take abs of ISCALE
iscale:
	fmov.s		FONE(%pc),%fp1	# init fp1 to 1
	bfextu		USER_FPCR(%a6){&26:&2},%d1	# get initial rmode bits
	lsl.w		&1,%d1		# put them in bits 2:1
	add.w		%d5,%d1		# add in LAMBDA
	lsl.w		&1,%d1		# put them in bits 3:1
	tst.l		L_SCR2(%a6)	# test sign of original x
	bge.b		x_pos		# if pos, don't set bit 0
	addq.l		&1,%d1		# if neg, set bit 0
x_pos:
	lea.l		RBDTBL(%pc),%a2	# load rbdtbl base
	mov.b		(%a2,%d1),%d3	# load d3 with new rmode
	lsl.l		&4,%d3		# put bits in proper position
	fmov.l		%d3,%fpcr	# load bits into fpu
	lsr.l		&4,%d3		# put bits in proper position
	tst.b		%d3		# decode new rmode for pten table
	bne.b		not_rn		# if zero, it is RN
	lea.l		PTENRN(%pc),%a1	# load a1 with RN table base
	bra.b		rmode		# exit decode
not_rn:
	lsr.b		&1,%d3		# get lsb in carry
	bcc.b		not_rp2		# if carry clear, it is RM
	lea.l		PTENRP(%pc),%a1	# load a1 with RP table base
	bra.b		rmode		# exit decode
not_rp2:
	lea.l		PTENRM(%pc),%a1	# load a1 with RM table base
rmode:
	clr.l		%d3		# clr table index
e_loop2:
	lsr.l		&1,%d0		# shift next bit into carry
	bcc.b		e_next2		# if zero, skip the mul
	fmul.x		(%a1,%d3),%fp1	# mul by 10**(d3_bit_no)
e_next2:
	add.l		&12,%d3		# inc d3 to next pwrten table entry
	tst.l		%d0		# test if ISCALE is zero
	bne.b		e_loop2		# if not, loop

# A8. Clr INEX; Force RZ.
#     The operation in A3 above may have set INEX2.  
#     RZ mode is forced for the scaling operation to insure
#     only one rounding error.  The grs bits are collected in 
#     the INEX flag for use in A10.
#
# Register usage:
#	Input/Output

	fmov.l		&0,%fpsr	# clr INEX 
	fmov.l		&rz_mode*0x10,%fpcr	# set RZ rounding mode

# A9. Scale X -> Y.
#     The mantissa is scaled to the desired number of significant
#     digits.  The excess digits are collected in INEX2. If mul,
#     Check d2 for excess 10 exponential value.  If not zero, 
#     the iscale value would have caused the pwrten calculation
#     to overflow.  Only a negative iscale can cause this, so
#     multiply by 10^(d2), which is now only allowed to be 24,
#     with a multiply by 10^8 and 10^16, which is exact since
#     10^24 is exact.  If the input was denormalized, we must
#     create a busy stack frame with the mul command and the
#     two operands, and allow the fpu to complete the multiply.
#
# Register usage:
#	Input/Output
#	d0: FPCR with RZ mode/Unchanged
#	d2: 0 or 24/unchanged
#	d3: x/x
#	d4: LEN/Unchanged
#	d5: ICTR:LAMBDA
#	d6: ILOG/Unchanged
#	d7: k-factor/Unchanged
#	a0: ptr for original operand/final result
#	a1: ptr to PTENRM array/Unchanged
#	a2: x/x
#	fp0: float(ILOG)/X adjusted for SCALE (Y)
#	fp1: 10^ISCALE/Unchanged
#	fp2: x/x
#	F_SCR1:x/x
#	F_SCR2:Abs(X) with $3fff exponent/Unchanged
#	L_SCR1:x/x
#	L_SCR2:first word of X packed/Unchanged

A9_str:
	fmov.x		(%a0),%fp0	# load X from memory
	fabs.x		%fp0		# use abs(X)
	tst.w		%d5		# LAMBDA is in lower word of d5
	bne.b		sc_mul		# if neg (LAMBDA = 1), scale by mul
	fdiv.x		%fp1,%fp0	# calculate X / SCALE -> Y to fp0
	bra.w		A10_st		# branch to A10

sc_mul:
	tst.b		BINDEC_FLG(%a6)	# check for denorm
	beq.w		A9_norm		# if norm, continue with mul

# for DENORM, we must calculate:
#	fp0 = input_op * 10^ISCALE * 10^24
# since the input operand is a DENORM, we can't multiply it directly.
# so, we do the multiplication of the exponents and mantissas separately.
# in this way, we avoid underflow on intermediate stages of the
# multiplication and guarantee a result without exception.
	fmovm.x		&0x2,-(%sp)	# save 10^ISCALE to stack

	mov.w		(%sp),%d3	# grab exponent
	andi.w		&0x7fff,%d3	# clear sign
	ori.w		&0x8000,(%a0)	# make DENORM exp negative
	add.w		(%a0),%d3	# add DENORM exp to 10^ISCALE exp
	subi.w		&0x3fff,%d3	# subtract BIAS
	add.w		36(%a1),%d3
	subi.w		&0x3fff,%d3	# subtract BIAS
	add.w		48(%a1),%d3
	subi.w		&0x3fff,%d3	# subtract BIAS

	bmi.w		sc_mul_err	# is result is DENORM, punt!!!

	andi.w		&0x8000,(%sp)	# keep sign
	or.w		%d3,(%sp)	# insert new exponent
	andi.w		&0x7fff,(%a0)	# clear sign bit on DENORM again
	mov.l		0x8(%a0),-(%sp) # put input op mantissa on stk
	mov.l		0x4(%a0),-(%sp)
	mov.l		&0x3fff0000,-(%sp) # force exp to zero
	fmovm.x		(%sp)+,&0x80	# load normalized DENORM into fp0
	fmul.x		(%sp)+,%fp0

#	fmul.x	36(%a1),%fp0	# multiply fp0 by 10^8
#	fmul.x	48(%a1),%fp0	# multiply fp0 by 10^16
	mov.l		36+8(%a1),-(%sp) # get 10^8 mantissa
	mov.l		36+4(%a1),-(%sp)
	mov.l		&0x3fff0000,-(%sp) # force exp to zero
	mov.l		48+8(%a1),-(%sp) # get 10^16 mantissa
	mov.l		48+4(%a1),-(%sp)
	mov.l		&0x3fff0000,-(%sp)# force exp to zero
	fmul.x		(%sp)+,%fp0	# multiply fp0 by 10^8
	fmul.x		(%sp)+,%fp0	# multiply fp0 by 10^16
	bra.b		A10_st

sc_mul_err:
	bra.b		sc_mul_err

A9_norm:
	tst.w		%d2		# test for small exp case
	beq.b		A9_con		# if zero, continue as normal
	fmul.x		36(%a1),%fp0	# multiply fp0 by 10^8
	fmul.x		48(%a1),%fp0	# multiply fp0 by 10^16
A9_con:
	fmul.x		%fp1,%fp0	# calculate X * SCALE -> Y to fp0

# A10. Or in INEX.
#      If INEX is set, round error occurred.  This is compensated
#      for by 'or-ing' in the INEX2 flag to the lsb of Y.
#
# Register usage:
#	Input/Output
#	d0: FPCR with RZ mode/FPSR with INEX2 isolated
#	d2: x/x
#	d3: x/x
#	d4: LEN/Unchanged
#	d5: ICTR:LAMBDA
#	d6: ILOG/Unchanged
#	d7: k-factor/Unchanged
#	a0: ptr for original operand/final result
#	a1: ptr to PTENxx array/Unchanged
#	a2: x/ptr to FP_SCR1(a6)
#	fp0: Y/Y with lsb adjusted
#	fp1: 10^ISCALE/Unchanged
#	fp2: x/x

A10_st:
	fmov.l		%fpsr,%d0	# get FPSR
	fmov.x		%fp0,FP_SCR1(%a6)	# move Y to memory
	lea.l		FP_SCR1(%a6),%a2	# load a2 with ptr to FP_SCR1
	btst		&9,%d0		# check if INEX2 set
	beq.b		A11_st		# if clear, skip rest
	or.l		&1,8(%a2)	# or in 1 to lsb of mantissa
	fmov.x		FP_SCR1(%a6),%fp0	# write adjusted Y back to fpu


# A11. Restore original FPCR; set size ext.
#      Perform FINT operation in the user's rounding mode.  Keep
#      the size to extended.  The sintdo entry point in the sint
#      routine expects the FPCR value to be in USER_FPCR for
#      mode and precision.  The original FPCR is saved in L_SCR1.

A11_st:
	mov.l		USER_FPCR(%a6),L_SCR1(%a6)	# save it for later
	and.l		&0x00000030,USER_FPCR(%a6)	# set size to ext, 
#					;block exceptions


# A12. Calculate YINT = FINT(Y) according to user's rounding mode.
#      The FPSP routine sintd0 is used.  The output is in fp0.
#
# Register usage:
#	Input/Output
#	d0: FPSR with AINEX cleared/FPCR with size set to ext
#	d2: x/x/scratch
#	d3: x/x
#	d4: LEN/Unchanged
#	d5: ICTR:LAMBDA/Unchanged
#	d6: ILOG/Unchanged
#	d7: k-factor/Unchanged
#	a0: ptr for original operand/src ptr for sintdo
#	a1: ptr to PTENxx array/Unchanged
#	a2: ptr to FP_SCR1(a6)/Unchanged
#	a6: temp pointer to FP_SCR1(a6) - orig value saved and restored
#	fp0: Y/YINT
#	fp1: 10^ISCALE/Unchanged
#	fp2: x/x
#	F_SCR1:x/x
#	F_SCR2:Y adjusted for inex/Y with original exponent
#	L_SCR1:x/original USER_FPCR
#	L_SCR2:first word of X packed/Unchanged

A12_st:
	movm.l	&0xc0c0,-(%sp)	# save regs used by sintd0	 {%d0-%d1/%a0-%a1}
	mov.l	L_SCR1(%a6),-(%sp)
	mov.l	L_SCR2(%a6),-(%sp)

	lea.l		FP_SCR1(%a6),%a0	# a0 is ptr to FP_SCR1(a6)
	fmov.x		%fp0,(%a0)	# move Y to memory at FP_SCR1(a6)
	tst.l		L_SCR2(%a6)	# test sign of original operand
	bge.b		do_fint12		# if pos, use Y 
	or.l		&0x80000000,(%a0)	# if neg, use -Y
do_fint12:
	mov.l	USER_FPSR(%a6),-(%sp)
#	bsr	sintdo		# sint routine returns int in fp0

	fmov.l	USER_FPCR(%a6),%fpcr
	fmov.l	&0x0,%fpsr			# clear the AEXC bits!!!
##	mov.l		USER_FPCR(%a6),%d0	# ext prec/keep rnd mode
##	andi.l		&0x00000030,%d0
##	fmov.l		%d0,%fpcr
	fint.x		FP_SCR1(%a6),%fp0	# do fint()
	fmov.l	%fpsr,%d0
	or.w	%d0,FPSR_EXCEPT(%a6)
##	fmov.l		&0x0,%fpcr
##	fmov.l		%fpsr,%d0		# don't keep ccodes
##	or.w		%d0,FPSR_EXCEPT(%a6)

	mov.b	(%sp),USER_FPSR(%a6)
	add.l	&4,%sp

	mov.l	(%sp)+,L_SCR2(%a6)
	mov.l	(%sp)+,L_SCR1(%a6)
	movm.l	(%sp)+,&0x303	# restore regs used by sint	 {%d0-%d1/%a0-%a1}

	mov.l	L_SCR2(%a6),FP_SCR1(%a6)	# restore original exponent
	mov.l	L_SCR1(%a6),USER_FPCR(%a6)	# restore user's FPCR

# A13. Check for LEN digits.
#      If the int operation results in more than LEN digits,
#      or less than LEN -1 digits, adjust ILOG and repeat from
#      A6.  This test occurs only on the first pass.  If the
#      result is exactly 10^LEN, decrement ILOG and divide
#      the mantissa by 10.  The calculation of 10^LEN cannot
#      be inexact, since all powers of ten upto 10^27 are exact
#      in extended precision, so the use of a previous power-of-ten
#      table will introduce no error.
#
#
# Register usage:
#	Input/Output
#	d0: FPCR with size set to ext/scratch final = 0
#	d2: x/x
#	d3: x/scratch final = x
#	d4: LEN/LEN adjusted
#	d5: ICTR:LAMBDA/LAMBDA:ICTR
#	d6: ILOG/ILOG adjusted
#	d7: k-factor/Unchanged
#	a0: pointer into memory for packed bcd string formation
#	a1: ptr to PTENxx array/Unchanged
#	a2: ptr to FP_SCR1(a6)/Unchanged
#	fp0: int portion of Y/abs(YINT) adjusted
#	fp1: 10^ISCALE/Unchanged
#	fp2: x/10^LEN
#	F_SCR1:x/x
#	F_SCR2:Y with original exponent/Unchanged
#	L_SCR1:original USER_FPCR/Unchanged
#	L_SCR2:first word of X packed/Unchanged

A13_st:
	swap		%d5		# put ICTR in lower word of d5
	tst.w		%d5		# check if ICTR = 0
	bne		not_zr		# if non-zero, go to second test
#
# Compute 10^(LEN-1)
#
	fmov.s		FONE(%pc),%fp2	# init fp2 to 1.0
	mov.l		%d4,%d0		# put LEN in d0
	subq.l		&1,%d0		# d0 = LEN -1
	clr.l		%d3		# clr table index
l_loop:
	lsr.l		&1,%d0		# shift next bit into carry
	bcc.b		l_next		# if zero, skip the mul
	fmul.x		(%a1,%d3),%fp2	# mul by 10**(d3_bit_no)
l_next:
	add.l		&12,%d3		# inc d3 to next pwrten table entry
	tst.l		%d0		# test if LEN is zero
	bne.b		l_loop		# if not, loop
#
# 10^LEN-1 is computed for this test and A14.  If the input was
# denormalized, check only the case in which YINT > 10^LEN.
#
	tst.b		BINDEC_FLG(%a6)	# check if input was norm
	beq.b		A13_con		# if norm, continue with checking
	fabs.x		%fp0		# take abs of YINT
	bra		test_2
#
# Compare abs(YINT) to 10^(LEN-1) and 10^LEN
#
A13_con:
	fabs.x		%fp0		# take abs of YINT
	fcmp.x		%fp0,%fp2	# compare abs(YINT) with 10^(LEN-1)
	fbge.w		test_2		# if greater, do next test
	subq.l		&1,%d6		# subtract 1 from ILOG
	mov.w		&1,%d5		# set ICTR
	fmov.l		&rm_mode*0x10,%fpcr	# set rmode to RM
	fmul.s		FTEN(%pc),%fp2	# compute 10^LEN 
	bra.w		A6_str		# return to A6 and recompute YINT
test_2:
	fmul.s		FTEN(%pc),%fp2	# compute 10^LEN
	fcmp.x		%fp0,%fp2	# compare abs(YINT) with 10^LEN
	fblt.w		A14_st		# if less, all is ok, go to A14
	fbgt.w		fix_ex		# if greater, fix and redo
	fdiv.s		FTEN(%pc),%fp0	# if equal, divide by 10
	addq.l		&1,%d6		# and inc ILOG
	bra.b		A14_st		# and continue elsewhere
fix_ex:
	addq.l		&1,%d6		# increment ILOG by 1
	mov.w		&1,%d5		# set ICTR
	fmov.l		&rm_mode*0x10,%fpcr	# set rmode to RM
	bra.w		A6_str		# return to A6 and recompute YINT
#
# Since ICTR <> 0, we have already been through one adjustment, 
# and shouldn't have another; this is to check if abs(YINT) = 10^LEN
# 10^LEN is again computed using whatever table is in a1 since the
# value calculated cannot be inexact.
#
not_zr:
	fmov.s		FONE(%pc),%fp2	# init fp2 to 1.0
	mov.l		%d4,%d0		# put LEN in d0
	clr.l		%d3		# clr table index
z_loop:
	lsr.l		&1,%d0		# shift next bit into carry
	bcc.b		z_next		# if zero, skip the mul
	fmul.x		(%a1,%d3),%fp2	# mul by 10**(d3_bit_no)
z_next:
	add.l		&12,%d3		# inc d3 to next pwrten table entry
	tst.l		%d0		# test if LEN is zero
	bne.b		z_loop		# if not, loop
	fabs.x		%fp0		# get abs(YINT)
	fcmp.x		%fp0,%fp2	# check if abs(YINT) = 10^LEN
	fbneq.w		A14_st		# if not, skip this
	fdiv.s		FTEN(%pc),%fp0	# divide abs(YINT) by 10
	addq.l		&1,%d6		# and inc ILOG by 1
	addq.l		&1,%d4		# and inc LEN
	fmul.s		FTEN(%pc),%fp2	# if LEN++, the get 10^^LEN

# A14. Convert the mantissa to bcd.
#      The binstr routine is used to convert the LEN digit 
#      mantissa to bcd in memory.  The input to binstr is
#      to be a fraction; i.e. (mantissa)/10^LEN and adjusted
#      such that the decimal point is to the left of bit 63.
#      The bcd digits are stored in the correct position in 
#      the final string area in memory.
#
#
# Register usage:
#	Input/Output
#	d0: x/LEN call to binstr - final is 0
#	d1: x/0
#	d2: x/ms 32-bits of mant of abs(YINT)
#	d3: x/ls 32-bits of mant of abs(YINT)
#	d4: LEN/Unchanged
#	d5: ICTR:LAMBDA/LAMBDA:ICTR
#	d6: ILOG
#	d7: k-factor/Unchanged
#	a0: pointer into memory for packed bcd string formation
#	    /ptr to first mantissa byte in result string
#	a1: ptr to PTENxx array/Unchanged
#	a2: ptr to FP_SCR1(a6)/Unchanged
#	fp0: int portion of Y/abs(YINT) adjusted
#	fp1: 10^ISCALE/Unchanged
#	fp2: 10^LEN/Unchanged
#	F_SCR1:x/Work area for final result
#	F_SCR2:Y with original exponent/Unchanged
#	L_SCR1:original USER_FPCR/Unchanged
#	L_SCR2:first word of X packed/Unchanged

A14_st:
	fmov.l		&rz_mode*0x10,%fpcr	# force rz for conversion
	fdiv.x		%fp2,%fp0	# divide abs(YINT) by 10^LEN
	lea.l		FP_SCR0(%a6),%a0
	fmov.x		%fp0,(%a0)	# move abs(YINT)/10^LEN to memory
	mov.l		4(%a0),%d2	# move 2nd word of FP_RES to d2
	mov.l		8(%a0),%d3	# move 3rd word of FP_RES to d3
	clr.l		4(%a0)		# zero word 2 of FP_RES
	clr.l		8(%a0)		# zero word 3 of FP_RES
	mov.l		(%a0),%d0	# move exponent to d0
	swap		%d0		# put exponent in lower word
	beq.b		no_sft		# if zero, don't shift
	sub.l		&0x3ffd,%d0	# sub bias less 2 to make fract
	tst.l		%d0		# check if > 1
	bgt.b		no_sft		# if so, don't shift
	neg.l		%d0		# make exp positive
m_loop:
	lsr.l		&1,%d2		# shift d2:d3 right, add 0s 
	roxr.l		&1,%d3		# the number of places
	dbf.w		%d0,m_loop	# given in d0
no_sft:
	tst.l		%d2		# check for mantissa of zero
	bne.b		no_zr		# if not, go on
	tst.l		%d3		# continue zero check
	beq.b		zer_m		# if zero, go directly to binstr
no_zr:
	clr.l		%d1		# put zero in d1 for addx
	add.l		&0x00000080,%d3	# inc at bit 7
	addx.l		%d1,%d2		# continue inc
	and.l		&0xffffff80,%d3	# strip off lsb not used by 882
zer_m:
	mov.l		%d4,%d0		# put LEN in d0 for binstr call
	addq.l		&3,%a0		# a0 points to M16 byte in result
	bsr		binstr		# call binstr to convert mant


# A15. Convert the exponent to bcd.
#      As in A14 above, the exp is converted to bcd and the
#      digits are stored in the final string.
#
#      Digits are stored in L_SCR1(a6) on return from BINDEC as:
#
#  	 32               16 15                0
#	-----------------------------------------
#  	|  0 | e3 | e2 | e1 | e4 |  X |  X |  X |
#	-----------------------------------------
#
# And are moved into their proper places in FP_SCR0.  If digit e4
# is non-zero, OPERR is signaled.  In all cases, all 4 digits are
# written as specified in the 881/882 manual for packed decimal.
#
# Register usage:
#	Input/Output
#	d0: x/LEN call to binstr - final is 0
#	d1: x/scratch (0);shift count for final exponent packing
#	d2: x/ms 32-bits of exp fraction/scratch
#	d3: x/ls 32-bits of exp fraction
#	d4: LEN/Unchanged
#	d5: ICTR:LAMBDA/LAMBDA:ICTR
#	d6: ILOG
#	d7: k-factor/Unchanged
#	a0: ptr to result string/ptr to L_SCR1(a6)
#	a1: ptr to PTENxx array/Unchanged
#	a2: ptr to FP_SCR1(a6)/Unchanged
#	fp0: abs(YINT) adjusted/float(ILOG)
#	fp1: 10^ISCALE/Unchanged
#	fp2: 10^LEN/Unchanged
#	F_SCR1:Work area for final result/BCD result
#	F_SCR2:Y with original exponent/ILOG/10^4
#	L_SCR1:original USER_FPCR/Exponent digits on return from binstr
#	L_SCR2:first word of X packed/Unchanged

A15_st:
	tst.b		BINDEC_FLG(%a6)	# check for denorm
	beq.b		not_denorm
	ftest.x		%fp0		# test for zero
	fbeq.w		den_zero	# if zero, use k-factor or 4933
	fmov.l		%d6,%fp0	# float ILOG
	fabs.x		%fp0		# get abs of ILOG
	bra.b		convrt
den_zero:
	tst.l		%d7		# check sign of the k-factor
	blt.b		use_ilog	# if negative, use ILOG
	fmov.s		F4933(%pc),%fp0	# force exponent to 4933
	bra.b		convrt		# do it
use_ilog:
	fmov.l		%d6,%fp0	# float ILOG
	fabs.x		%fp0		# get abs of ILOG
	bra.b		convrt
not_denorm:
	ftest.x		%fp0		# test for zero
	fbneq.w		not_zero	# if zero, force exponent
	fmov.s		FONE(%pc),%fp0	# force exponent to 1
	bra.b		convrt		# do it
not_zero:
	fmov.l		%d6,%fp0	# float ILOG
	fabs.x		%fp0		# get abs of ILOG
convrt:
	fdiv.x		24(%a1),%fp0	# compute ILOG/10^4
	fmov.x		%fp0,FP_SCR1(%a6)	# store fp0 in memory
	mov.l		4(%a2),%d2	# move word 2 to d2
	mov.l		8(%a2),%d3	# move word 3 to d3
	mov.w		(%a2),%d0	# move exp to d0
	beq.b		x_loop_fin	# if zero, skip the shift
	sub.w		&0x3ffd,%d0	# subtract off bias
	neg.w		%d0		# make exp positive
x_loop:
	lsr.l		&1,%d2		# shift d2:d3 right 
	roxr.l		&1,%d3		# the number of places
	dbf.w		%d0,x_loop	# given in d0
x_loop_fin:
	clr.l		%d1		# put zero in d1 for addx
	add.l		&0x00000080,%d3	# inc at bit 6
	addx.l		%d1,%d2		# continue inc
	and.l		&0xffffff80,%d3	# strip off lsb not used by 882
	mov.l		&4,%d0		# put 4 in d0 for binstr call
	lea.l		L_SCR1(%a6),%a0	# a0 is ptr to L_SCR1 for exp digits
	bsr		binstr		# call binstr to convert exp
	mov.l		L_SCR1(%a6),%d0	# load L_SCR1 lword to d0 
	mov.l		&12,%d1		# use d1 for shift count
	lsr.l		%d1,%d0		# shift d0 right by 12
	bfins		%d0,FP_SCR0(%a6){&4:&12}	# put e3:e2:e1 in FP_SCR0
	lsr.l		%d1,%d0		# shift d0 right by 12
	bfins		%d0,FP_SCR0(%a6){&16:&4}	# put e4 in FP_SCR0 
	tst.b		%d0		# check if e4 is zero
	beq.b		A16_st		# if zero, skip rest
	or.l		&opaop_mask,USER_FPSR(%a6)	# set OPERR & AIOP in USER_FPSR


# A16. Write sign bits to final string.
#	   Sigma is bit 31 of initial value; RHO is bit 31 of d6 (ILOG).
#
# Register usage:
#	Input/Output
#	d0: x/scratch - final is x
#	d2: x/x
#	d3: x/x
#	d4: LEN/Unchanged
#	d5: ICTR:LAMBDA/LAMBDA:ICTR
#	d6: ILOG/ILOG adjusted
#	d7: k-factor/Unchanged
#	a0: ptr to L_SCR1(a6)/Unchanged
#	a1: ptr to PTENxx array/Unchanged
#	a2: ptr to FP_SCR1(a6)/Unchanged
#	fp0: float(ILOG)/Unchanged
#	fp1: 10^ISCALE/Unchanged
#	fp2: 10^LEN/Unchanged
#	F_SCR1:BCD result with correct signs
#	F_SCR2:ILOG/10^4
#	L_SCR1:Exponent digits on return from binstr
#	L_SCR2:first word of X packed/Unchanged

A16_st:
	clr.l		%d0		# clr d0 for collection of signs
	and.b		&0x0f,FP_SCR0(%a6)	# clear first nibble of FP_SCR0 
	tst.l		L_SCR2(%a6)	# check sign of original mantissa
	bge.b		mant_p		# if pos, don't set SM
	mov.l		&2,%d0		# move 2 in to d0 for SM
mant_p:
	tst.l		%d6		# check sign of ILOG
	bge.b		wr_sgn		# if pos, don't set SE
	addq.l		&1,%d0		# set bit 0 in d0 for SE 
wr_sgn:
	bfins		%d0,FP_SCR0(%a6){&0:&2}	# insert SM and SE into FP_SCR0

# Clean up and restore all registers used.

	fmov.l		&0,%fpsr	# clear possible inex2/ainex bits
	fmovm.x		(%sp)+,&0xe0	#  {%fp0-%fp2}
	movm.l		(%sp)+,&0x4fc	#  {%d2-%d7/%a2}
	rts

	global		PTENRN
PTENRN:
	long		0x40020000,0xA0000000,0x00000000	# 10 ^ 1
	long		0x40050000,0xC8000000,0x00000000	# 10 ^ 2
	long		0x400C0000,0x9C400000,0x00000000	# 10 ^ 4
	long		0x40190000,0xBEBC2000,0x00000000	# 10 ^ 8
	long		0x40340000,0x8E1BC9BF,0x04000000	# 10 ^ 16
	long		0x40690000,0x9DC5ADA8,0x2B70B59E	# 10 ^ 32
	long		0x40D30000,0xC2781F49,0xFFCFA6D5	# 10 ^ 64
	long		0x41A80000,0x93BA47C9,0x80E98CE0	# 10 ^ 128
	long		0x43510000,0xAA7EEBFB,0x9DF9DE8E	# 10 ^ 256
	long		0x46A30000,0xE319A0AE,0xA60E91C7	# 10 ^ 512
	long		0x4D480000,0xC9767586,0x81750C17	# 10 ^ 1024
	long		0x5A920000,0x9E8B3B5D,0xC53D5DE5	# 10 ^ 2048
	long		0x75250000,0xC4605202,0x8A20979B	# 10 ^ 4096

	global		PTENRP
PTENRP:
	long		0x40020000,0xA0000000,0x00000000	# 10 ^ 1
	long		0x40050000,0xC8000000,0x00000000	# 10 ^ 2
	long		0x400C0000,0x9C400000,0x00000000	# 10 ^ 4
	long		0x40190000,0xBEBC2000,0x00000000	# 10 ^ 8
	long		0x40340000,0x8E1BC9BF,0x04000000	# 10 ^ 16
	long		0x40690000,0x9DC5ADA8,0x2B70B59E	# 10 ^ 32
	long		0x40D30000,0xC2781F49,0xFFCFA6D6	# 10 ^ 64
	long		0x41A80000,0x93BA47C9,0x80E98CE0	# 10 ^ 128
	long		0x43510000,0xAA7EEBFB,0x9DF9DE8E	# 10 ^ 256
	long		0x46A30000,0xE319A0AE,0xA60E91C7	# 10 ^ 512
	long		0x4D480000,0xC9767586,0x81750C18	# 10 ^ 1024
	long		0x5A920000,0x9E8B3B5D,0xC53D5DE5	# 10 ^ 2048
	long		0x75250000,0xC4605202,0x8A20979B	# 10 ^ 4096

	global		PTENRM
PTENRM:
	long		0x40020000,0xA0000000,0x00000000	# 10 ^ 1
	long		0x40050000,0xC8000000,0x00000000	# 10 ^ 2
	long		0x400C0000,0x9C400000,0x00000000	# 10 ^ 4
	long		0x40190000,0xBEBC2000,0x00000000	# 10 ^ 8
	long		0x40340000,0x8E1BC9BF,0x04000000	# 10 ^ 16
	long		0x40690000,0x9DC5ADA8,0x2B70B59D	# 10 ^ 32
	long		0x40D30000,0xC2781F49,0xFFCFA6D5	# 10 ^ 64
	long		0x41A80000,0x93BA47C9,0x80E98CDF	# 10 ^ 128
	long		0x43510000,0xAA7EEBFB,0x9DF9DE8D	# 10 ^ 256
	long		0x46A30000,0xE319A0AE,0xA60E91C6	# 10 ^ 512
	long		0x4D480000,0xC9767586,0x81750C17	# 10 ^ 1024
	long		0x5A920000,0x9E8B3B5D,0xC53D5DE4	# 10 ^ 2048
	long		0x75250000,0xC4605202,0x8A20979A	# 10 ^ 4096

#########################################################################
# binstr(): Converts a 64-bit binary integer to bcd.			#
#									#
# INPUT *************************************************************** #
#	d2:d3 = 64-bit binary integer					#
#	d0    = desired length (LEN)					#
#	a0    = pointer to start in memory for bcd characters		#
#          	(This pointer must point to byte 4 of the first		#
#          	 lword of the packed decimal memory string.)		#
#									#
# OUTPUT ************************************************************** #
#	a0 = pointer to LEN bcd digits representing the 64-bit integer.	#
#									#
# ALGORITHM ***********************************************************	#
#	The 64-bit binary is assumed to have a decimal point before	#
#	bit 63.  The fraction is multiplied by 10 using a mul by 2	#
#	shift and a mul by 8 shift.  The bits shifted out of the	#
#	msb form a decimal digit.  This process is iterated until	#
#	LEN digits are formed.						#
#									#
# A1. Init d7 to 1.  D7 is the byte digit counter, and if 1, the	#
#     digit formed will be assumed the least significant.  This is	#
#     to force the first byte formed to have a 0 in the upper 4 bits.	#
#									#
# A2. Beginning of the loop:						#
#     Copy the fraction in d2:d3 to d4:d5.				#
#									#
# A3. Multiply the fraction in d2:d3 by 8 using bit-field		#
#     extracts and shifts.  The three msbs from d2 will go into d1.	#
#									#
# A4. Multiply the fraction in d4:d5 by 2 using shifts.  The msb	#
#     will be collected by the carry.					#
#									#
# A5. Add using the carry the 64-bit quantities in d2:d3 and d4:d5	#
#     into d2:d3.  D1 will contain the bcd digit formed.		#
#									#
# A6. Test d7.  If zero, the digit formed is the ms digit.  If non-	#
#     zero, it is the ls digit.  Put the digit in its place in the	#
#     upper word of d0.  If it is the ls digit, write the word		#
#     from d0 to memory.						#
#									#
# A7. Decrement d6 (LEN counter) and repeat the loop until zero.	#
#									#
#########################################################################

#	Implementation Notes:
#
#	The registers are used as follows:
#
#		d0: LEN counter
#		d1: temp used to form the digit
#		d2: upper 32-bits of fraction for mul by 8
#		d3: lower 32-bits of fraction for mul by 8
#		d4: upper 32-bits of fraction for mul by 2
#		d5: lower 32-bits of fraction for mul by 2
#		d6: temp for bit-field extracts
#		d7: byte digit formation word;digit count {0,1}
#		a0: pointer into memory for packed bcd string formation
#

	global		binstr
binstr:
	movm.l		&0xff00,-(%sp)	#  {%d0-%d7}

#
# A1: Init d7
#
	mov.l		&1,%d7		# init d7 for second digit
	subq.l		&1,%d0		# for dbf d0 would have LEN+1 passes
#
# A2. Copy d2:d3 to d4:d5.  Start loop.
#
loop:
	mov.l		%d2,%d4		# copy the fraction before muls
	mov.l		%d3,%d5		# to d4:d5
#
# A3. Multiply d2:d3 by 8; extract msbs into d1.
#
	bfextu		%d2{&0:&3},%d1	# copy 3 msbs of d2 into d1
	asl.l		&3,%d2		# shift d2 left by 3 places
	bfextu		%d3{&0:&3},%d6	# copy 3 msbs of d3 into d6
	asl.l		&3,%d3		# shift d3 left by 3 places
	or.l		%d6,%d2		# or in msbs from d3 into d2
#
# A4. Multiply d4:d5 by 2; add carry out to d1.
#
	asl.l		&1,%d5		# mul d5 by 2
	roxl.l		&1,%d4		# mul d4 by 2
	swap		%d6		# put 0 in d6 lower word
	addx.w		%d6,%d1		# add in extend from mul by 2
#
# A5. Add mul by 8 to mul by 2.  D1 contains the digit formed.
#
	add.l		%d5,%d3		# add lower 32 bits
	nop				# ERRATA FIX #13 (Rev. 1.2 6/6/90)
	addx.l		%d4,%d2		# add with extend upper 32 bits
	nop				# ERRATA FIX #13 (Rev. 1.2 6/6/90)
	addx.w		%d6,%d1		# add in extend from add to d1
	swap		%d6		# with d6 = 0; put 0 in upper word
#
# A6. Test d7 and branch.
#
	tst.w		%d7		# if zero, store digit & to loop
	beq.b		first_d		# if non-zero, form byte & write
sec_d:
	swap		%d7		# bring first digit to word d7b
	asl.w		&4,%d7		# first digit in upper 4 bits d7b
	add.w		%d1,%d7		# add in ls digit to d7b
	mov.b		%d7,(%a0)+	# store d7b byte in memory
	swap		%d7		# put LEN counter in word d7a
	clr.w		%d7		# set d7a to signal no digits done
	dbf.w		%d0,loop	# do loop some more!
	bra.b		end_bstr	# finished, so exit
first_d:
	swap		%d7		# put digit word in d7b
	mov.w		%d1,%d7		# put new digit in d7b
	swap		%d7		# put LEN counter in word d7a
	addq.w		&1,%d7		# set d7a to signal first digit done
	dbf.w		%d0,loop	# do loop some more!
	swap		%d7		# put last digit in string
	lsl.w		&4,%d7		# move it to upper 4 bits
	mov.b		%d7,(%a0)+	# store it in memory string
#
# Clean up and return with result in fp0.
#
end_bstr:
	movm.l		(%sp)+,&0xff	#  {%d0-%d7}
	rts

#########################################################################
# XDEF ****************************************************************	#
#	facc_in_b(): dmem_read_byte failed				#
#	facc_in_w(): dmem_read_word failed				#
#	facc_in_l(): dmem_read_long failed				#
#	facc_in_d(): dmem_read of dbl prec failed			#
#	facc_in_x(): dmem_read of ext prec failed			#
#									#
#	facc_out_b(): dmem_write_byte failed				#
#	facc_out_w(): dmem_write_word failed				#
#	facc_out_l(): dmem_write_long failed				#
#	facc_out_d(): dmem_write of dbl prec failed			#
#	facc_out_x(): dmem_write of ext prec failed			#
#									#
# XREF ****************************************************************	#
#	_real_access() - exit through access error handler		#
#									#
# INPUT ***************************************************************	#
#	None								#
# 									#
# OUTPUT **************************************************************	#
#	None								#
#									#
# ALGORITHM ***********************************************************	#
# 	Flow jumps here when an FP data fetch call gets an error 	#
# result. This means the operating system wants an access error frame	#
# made out of the current exception stack frame. 			#
#	So, we first call restore() which makes sure that any updated	#
# -(an)+ register gets returned to its pre-exception value and then	#
# we change the stack to an access error stack frame.			#
#									#
#########################################################################

facc_in_b:
	movq.l		&0x1,%d0			# one byte
	bsr.w		restore				# fix An

	mov.w		&0x0121,EXC_VOFF(%a6)		# set FSLW
	bra.w		facc_finish

facc_in_w:
	movq.l		&0x2,%d0			# two bytes
	bsr.w		restore				# fix An

	mov.w		&0x0141,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

facc_in_l:
	movq.l		&0x4,%d0			# four bytes
	bsr.w		restore				# fix An

	mov.w		&0x0101,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

facc_in_d:
	movq.l		&0x8,%d0			# eight bytes
	bsr.w		restore				# fix An

	mov.w		&0x0161,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

facc_in_x:
	movq.l		&0xc,%d0			# twelve bytes
	bsr.w		restore				# fix An

	mov.w		&0x0161,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

################################################################

facc_out_b:
	movq.l		&0x1,%d0			# one byte
	bsr.w		restore				# restore An

	mov.w		&0x00a1,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

facc_out_w:
	movq.l		&0x2,%d0			# two bytes
	bsr.w		restore				# restore An

	mov.w		&0x00c1,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

facc_out_l:
	movq.l		&0x4,%d0			# four bytes
	bsr.w		restore				# restore An

	mov.w		&0x0081,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

facc_out_d:
	movq.l		&0x8,%d0			# eight bytes
	bsr.w		restore				# restore An

	mov.w		&0x00e1,EXC_VOFF(%a6)		# set FSLW
	bra.b		facc_finish

facc_out_x:
	mov.l		&0xc,%d0			# twelve bytes
	bsr.w		restore				# restore An

	mov.w		&0x00e1,EXC_VOFF(%a6)		# set FSLW

# here's where we actually create the access error frame from the
# current exception stack frame.
facc_finish:
	mov.l		USER_FPIAR(%a6),EXC_PC(%a6) # store current PC

	fmovm.x		EXC_FPREGS(%a6),&0xc0	# restore fp0-fp1
	fmovm.l		USER_FPCR(%a6),%fpcr,%fpsr,%fpiar # restore ctrl regs
	movm.l		EXC_DREGS(%a6),&0x0303	# restore d0-d1/a0-a1

	unlk		%a6

	mov.l		(%sp),-(%sp)		# store SR, hi(PC)
	mov.l		0x8(%sp),0x4(%sp)	# store lo(PC)
	mov.l		0xc(%sp),0x8(%sp)	# store EA
	mov.l		&0x00000001,0xc(%sp)	# store FSLW
	mov.w		0x6(%sp),0xc(%sp)	# fix FSLW (size)
	mov.w		&0x4008,0x6(%sp)	# store voff

	btst		&0x5,(%sp)		# supervisor or user mode?
	beq.b		facc_out2		# user
	bset		&0x2,0xd(%sp)		# set supervisor TM bit

facc_out2:
	bra.l		_real_access

##################################################################

# if the effective addressing mode was predecrement or postincrement,
# the emulation has already changed its value to the correct post-
# instruction value. but since we're exiting to the access error
# handler, then AN must be returned to its pre-instruction value.
# we do that here.
restore:
	mov.b		EXC_OPWORD+0x1(%a6),%d1
	andi.b		&0x38,%d1		# extract opmode
	cmpi.b		%d1,&0x18		# postinc?
	beq.w		rest_inc
	cmpi.b		%d1,&0x20		# predec?
	beq.w		rest_dec
	rts

rest_inc:
	mov.b		EXC_OPWORD+0x1(%a6),%d1
	andi.w		&0x0007,%d1		# fetch An

	mov.w		(tbl_rest_inc.b,%pc,%d1.w*2),%d1
	jmp		(tbl_rest_inc.b,%pc,%d1.w*1)

tbl_rest_inc:
	short		ri_a0 - tbl_rest_inc
	short		ri_a1 - tbl_rest_inc
	short		ri_a2 - tbl_rest_inc
	short		ri_a3 - tbl_rest_inc
	short		ri_a4 - tbl_rest_inc
	short		ri_a5 - tbl_rest_inc
	short		ri_a6 - tbl_rest_inc
	short		ri_a7 - tbl_rest_inc

ri_a0:
	sub.l		%d0,EXC_DREGS+0x8(%a6)	# fix stacked a0
	rts
ri_a1:
	sub.l		%d0,EXC_DREGS+0xc(%a6)	# fix stacked a1
	rts
ri_a2:
	sub.l		%d0,%a2			# fix a2
	rts
ri_a3:
	sub.l		%d0,%a3			# fix a3
	rts
ri_a4:
	sub.l		%d0,%a4			# fix a4
	rts
ri_a5:
	sub.l		%d0,%a5			# fix a5
	rts
ri_a6:
	sub.l		%d0,(%a6)		# fix stacked a6
	rts
# if it's a fmove out instruction, we don't have to fix a7
# because we hadn't changed it yet. if it's an opclass two
# instruction (data moved in) and the exception was in supervisor
# mode, then also also wasn't updated. if it was user mode, then
# restore the correct a7 which is in the USP currently.
ri_a7:
	cmpi.b		EXC_VOFF(%a6),&0x30	# move in or out?
	bne.b		ri_a7_done		# out

	btst		&0x5,EXC_SR(%a6)	# user or supervisor?
	bne.b		ri_a7_done		# supervisor
	movc		%usp,%a0		# restore USP
	sub.l		%d0,%a0
	movc		%a0,%usp	
ri_a7_done:
	rts

# need to invert adjustment value if the <ea> was predec
rest_dec:
	neg.l		%d0
	bra.b		rest_inc
