patch-1.3.94 linux/arch/m68k/fpsp040/get_op.S

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diff -u --recursive --new-file v1.3.93/linux/arch/m68k/fpsp040/get_op.S linux/arch/m68k/fpsp040/get_op.S
@@ -0,0 +1,676 @@
+|
+|	get_op.sa 3.6 5/19/92
+|
+|	get_op.sa 3.5 4/26/91
+|
+|  Description: This routine is called by the unsupported format/data
+| type exception handler ('unsupp' - vector 55) and the unimplemented
+| instruction exception handler ('unimp' - vector 11).  'get_op'
+| determines the opclass (0, 2, or 3) and branches to the
+| opclass handler routine.  See 68881/2 User's Manual table 4-11
+| for a description of the opclasses.
+|
+| For UNSUPPORTED data/format (exception vector 55) and for
+| UNIMPLEMENTED instructions (exception vector 11) the following
+| applies:
+|
+| - For unnormormalized numbers (opclass 0, 2, or 3) the
+| number(s) is normalized and the operand type tag is updated.
+|		
+| - For a packed number (opclass 2) the number is unpacked and the
+| operand type tag is updated.
+|
+| - For denormalized numbers (opclass 0 or 2) the number(s) is not
+| changed but passed to the next module.  The next module for
+| unimp is do_func, the next module for unsupp is res_func.
+|
+| For UNSUPPORTED data/format (exception vector 55) only the
+| following applies:
+|
+| - If there is a move out with a packed number (opclass 3) the
+| number is packed and written to user memory.  For the other
+| opclasses the number(s) are written back to the fsave stack
+| and the instruction is then restored back into the '040.  The
+| '040 is then able to complete the instruction.
+|
+| For example:
+| fadd.x fpm,fpn where the fpm contains an unnormalized number.
+| The '040 takes an unsupported data trap and gets to this
+| routine.  The number is normalized, put back on the stack and
+| then an frestore is done to restore the instruction back into
+| the '040.  The '040 then re-executes the fadd.x fpm,fpn with
+| a normalized number in the source and the instruction is
+| successful.
+|		
+| Next consider if in the process of normalizing the un-
+| normalized number it becomes a denormalized number.  The
+| routine which converts the unnorm to a norm (called mk_norm)
+| detects this and tags the number as a denorm.  The routine
+| res_func sees the denorm tag and converts the denorm to a
+| norm.  The instruction is then restored back into the '040
+| which re_executess the instruction.
+|
+|
+|		Copyright (C) Motorola, Inc. 1990
+|			All Rights Reserved
+|
+|	THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA 
+|	The copyright notice above does not evidence any  
+|	actual or intended publication of such source code.
+
+GET_OP:    |idnt    2,1 | Motorola 040 Floating Point Software Package
+
+	|section	8
+
+	.include "fpsp.h"
+
+	.global	PIRN,PIRZRM,PIRP
+	.global	SMALRN,SMALRZRM,SMALRP
+	.global	BIGRN,BIGRZRM,BIGRP
+
+PIRN:
+	.long 0x40000000,0xc90fdaa2,0x2168c235    |pi
+PIRZRM:
+	.long 0x40000000,0xc90fdaa2,0x2168c234    |pi
+PIRP:
+	.long 0x40000000,0xc90fdaa2,0x2168c235    |pi
+
+|round to nearest
+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
+| round to zero;round to negative infinity
+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
+| round to positive infinity
+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
+
+|round to nearest
+BIGRN:
+	.long 0x3ffe0000,0xb17217f7,0xd1cf79ac    |ln(2)
+	.long 0x40000000,0x935d8ddd,0xaaa8ac17    |ln(10)
+	.long 0x3fff0000,0x80000000,0x00000000    |10 ^ 0
+
+	.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
+|round to minus infinity
+BIGRZRM:
+	.long 0x3ffe0000,0xb17217f7,0xd1cf79ab    |ln(2)
+	.long 0x40000000,0x935d8ddd,0xaaa8ac16    |ln(10)
+	.long 0x3fff0000,0x80000000,0x00000000    |10 ^ 0
+
+	.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,0xC53D5DE5    |10 ^ 2048
+	.long 0x75250000,0xC4605202,0x8A20979A    |10 ^ 4096
+|round to positive infinity
+BIGRP:
+	.long 0x3ffe0000,0xb17217f7,0xd1cf79ac    |ln(2)
+	.long 0x40000000,0x935d8ddd,0xaaa8ac17    |ln(10)
+	.long 0x3fff0000,0x80000000,0x00000000    |10 ^ 0
+
+	.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,0xC53D5DE6    |10 ^ 2048
+	.long 0x75250000,0xC4605202,0x8A20979B    |10 ^ 4096
+
+	|xref	nrm_zero
+	|xref	decbin
+	|xref	round
+
+	.global    get_op
+	.global    uns_getop
+	.global    uni_getop
+get_op:
+	clrb	DY_MO_FLG(%a6)
+	tstb	UFLG_TMP(%a6)	|test flag for unsupp/unimp state
+	beqs	uni_getop
+
+uns_getop:
+	btstb	#direction_bit,CMDREG1B(%a6)
+	bne	opclass3	|branch if a fmove out (any kind)
+	btstb	#6,CMDREG1B(%a6)
+	beqs	uns_notpacked
+
+	bfextu	CMDREG1B(%a6){#3:#3},%d0
+	cmpb	#3,%d0
+	beq	pack_source	|check for a packed src op, branch if so
+uns_notpacked:
+	bsr	chk_dy_mo	|set the dyadic/monadic flag
+	tstb	DY_MO_FLG(%a6)
+	beqs	src_op_ck	|if monadic, go check src op
+|				;else, check dst op (fall through)
+
+	btstb	#7,DTAG(%a6)
+	beqs	src_op_ck	|if dst op is norm, check src op
+	bras	dst_ex_dnrm	|else, handle destination unnorm/dnrm
+
+uni_getop:
+	bfextu	CMDREG1B(%a6){#0:#6},%d0 |get opclass and src fields
+	cmpil	#0x17,%d0		|if op class and size fields are $17, 
+|				;it is FMOVECR; if not, continue
+|
+| If the instruction is fmovecr, exit get_op.  It is handled
+| in do_func and smovecr.sa.
+|
+	bne	not_fmovecr	|handle fmovecr as an unimplemented inst
+	rts
+
+not_fmovecr:
+	btstb	#E1,E_BYTE(%a6)	|if set, there is a packed operand
+	bne	pack_source	|check for packed src op, branch if so
+
+| The following lines of are coded to optimize on normalized operands
+	moveb	STAG(%a6),%d0
+	orb	DTAG(%a6),%d0	|check if either of STAG/DTAG msb set
+	bmis	dest_op_ck	|if so, some op needs to be fixed
+	rts
+
+dest_op_ck:
+	btstb	#7,DTAG(%a6)	|check for unsupported data types in
+	beqs	src_op_ck	|the destination, if not, check src op
+	bsr	chk_dy_mo	|set dyadic/monadic flag
+	tstb	DY_MO_FLG(%a6)	|
+	beqs	src_op_ck	|if monadic, check src op
+|
+| At this point, destination has an extended denorm or unnorm.
+|
+dst_ex_dnrm:
+	movew	FPTEMP_EX(%a6),%d0 |get destination exponent
+	andiw	#0x7fff,%d0	|mask sign, check if exp = 0000
+	beqs	src_op_ck	|if denorm then check source op.
+|				;denorms are taken care of in res_func 
+|				;(unsupp) or do_func (unimp)
+|				;else unnorm fall through
+	leal	FPTEMP(%a6),%a0	|point a0 to dop - used in mk_norm
+	bsr	mk_norm		|go normalize - mk_norm returns:
+|				;L_SCR1{7:5} = operand tag 
+|				;	(000 = norm, 100 = denorm)
+|				;L_SCR1{4} = fpte15 or ete15 
+|				;	0 = exp >  $3fff
+|				;	1 = exp <= $3fff
+|				;and puts the normalized num back 
+|				;on the fsave stack
+|
+	moveb L_SCR1(%a6),DTAG(%a6) |write the new tag & fpte15 
+|				;to the fsave stack and fall 
+|				;through to check source operand
+|
+src_op_ck:
+	btstb	#7,STAG(%a6)
+	beq	end_getop	|check for unsupported data types on the
+|				;source operand
+	btstb	#5,STAG(%a6)
+	bnes	src_sd_dnrm	|if bit 5 set, handle sgl/dbl denorms
+|
+| At this point only unnorms or extended denorms are possible.
+|
+src_ex_dnrm:
+	movew	ETEMP_EX(%a6),%d0 |get source exponent
+	andiw	#0x7fff,%d0	|mask sign, check if exp = 0000
+	beq	end_getop	|if denorm then exit, denorms are 
+|				;handled in do_func
+	leal	ETEMP(%a6),%a0	|point a0 to sop - used in mk_norm
+	bsr	mk_norm		|go normalize - mk_norm returns:
+|				;L_SCR1{7:5} = operand tag 
+|				;	(000 = norm, 100 = denorm)
+|				;L_SCR1{4} = fpte15 or ete15 
+|				;	0 = exp >  $3fff
+|				;	1 = exp <= $3fff
+|				;and puts the normalized num back 
+|				;on the fsave stack
+|
+	moveb	L_SCR1(%a6),STAG(%a6) |write the new tag & ete15 
+	rts			|end_getop
+
+|
+| At this point, only single or double denorms are possible.
+| If the inst is not fmove, normalize the source.  If it is,
+| do nothing to the input.
+|
+src_sd_dnrm:
+	btstb	#4,CMDREG1B(%a6)	|differentiate between sgl/dbl denorm
+	bnes	is_double
+is_single:
+	movew	#0x3f81,%d1	|write bias for sgl denorm
+	bras	common		|goto the common code
+is_double:
+	movew	#0x3c01,%d1	|write the bias for a dbl denorm
+common:
+	btstb	#sign_bit,ETEMP_EX(%a6) |grab sign bit of mantissa
+	beqs	pos	
+	bset	#15,%d1		|set sign bit because it is negative
+pos:
+	movew	%d1,ETEMP_EX(%a6)
+|				;put exponent on stack
+
+	movew	CMDREG1B(%a6),%d1
+	andw	#0xe3ff,%d1	|clear out source specifier
+	orw	#0x0800,%d1	|set source specifier to extended prec
+	movew	%d1,CMDREG1B(%a6)	|write back to the command word in stack
+|				;this is needed to fix unsupp data stack
+	leal	ETEMP(%a6),%a0	|point a0 to sop
+	
+	bsr	mk_norm		|convert sgl/dbl denorm to norm
+	moveb	L_SCR1(%a6),STAG(%a6) |put tag into source tag reg - d0
+	rts			|end_getop
+|
+| At this point, the source is definitely packed, whether
+| instruction is dyadic or monadic is still unknown
+|
+pack_source:
+	movel	FPTEMP_LO(%a6),ETEMP(%a6)	|write ms part of packed 
+|				;number to etemp slot
+	bsr	chk_dy_mo	|set dyadic/monadic flag
+	bsr	unpack
+
+	tstb	DY_MO_FLG(%a6)
+	beqs	end_getop	|if monadic, exit
+|				;else, fix FPTEMP
+pack_dya:
+	bfextu	CMDREG1B(%a6){#6:#3},%d0 |extract dest fp reg
+	movel	#7,%d1
+	subl	%d0,%d1
+	clrl	%d0
+	bsetl	%d1,%d0		|set up d0 as a dynamic register mask
+	fmovemx %d0,FPTEMP(%a6)	|write to FPTEMP
+
+	btstb	#7,DTAG(%a6)	|check dest tag for unnorm or denorm
+	bne	dst_ex_dnrm	|else, handle the unnorm or ext denorm
+|
+| Dest is not denormalized.  Check for norm, and set fpte15 
+| accordingly.
+|
+	moveb	DTAG(%a6),%d0
+	andib	#0xf0,%d0		|strip to only dtag:fpte15
+	tstb	%d0		|check for normalized value
+	bnes	end_getop	|if inf/nan/zero leave get_op
+	movew	FPTEMP_EX(%a6),%d0
+	andiw	#0x7fff,%d0
+	cmpiw	#0x3fff,%d0	|check if fpte15 needs setting
+	bges	end_getop	|if >= $3fff, leave fpte15=0
+	orb	#0x10,DTAG(%a6)
+	bras	end_getop
+
+|
+| At this point, it is either an fmoveout packed, unnorm or denorm
+|
+opclass3:
+	clrb	DY_MO_FLG(%a6)	|set dyadic/monadic flag to monadic
+	bfextu	CMDREG1B(%a6){#4:#2},%d0
+	cmpib	#3,%d0
+	bne	src_ex_dnrm	|if not equal, must be unnorm or denorm
+|				;else it is a packed move out
+|				;exit
+end_getop:
+	rts
+
+|
+| Sets the DY_MO_FLG correctly. This is used only on if it is an
+| unuspported data type exception.  Set if dyadic.
+|
+chk_dy_mo:
+	movew	CMDREG1B(%a6),%d0	
+	btstl	#5,%d0		|testing extension command word
+	beqs	set_mon		|if bit 5 = 0 then monadic
+	btstl	#4,%d0		|know that bit 5 = 1
+	beqs	set_dya		|if bit 4 = 0 then dyadic
+	andiw	#0x007f,%d0	|get rid of all but extension bits {6:0}
+	cmpiw 	#0x0038,%d0	|if extension = $38 then fcmp (dyadic)
+	bnes	set_mon
+set_dya:
+	st	DY_MO_FLG(%a6)	|set the inst flag type to dyadic
+	rts
+set_mon:
+	clrb	DY_MO_FLG(%a6)	|set the inst flag type to monadic
+	rts
+|
+|	MK_NORM
+|
+| Normalizes unnormalized numbers, sets tag to norm or denorm, sets unfl
+| exception if denorm.
+|
+| CASE opclass 0x0 unsupp
+|	mk_norm till msb set
+|	set tag = norm
+|
+| CASE opclass 0x0 unimp
+|	mk_norm till msb set or exp = 0
+|	if integer bit = 0
+|	   tag = denorm
+|	else
+|	   tag = norm
+|
+| CASE opclass 011 unsupp
+|	mk_norm till msb set or exp = 0
+|	if integer bit = 0
+|	   tag = denorm
+|	   set unfl_nmcexe = 1
+|	else
+|	   tag = norm
+|
+| if exp <= $3fff
+|   set ete15 or fpte15 = 1
+| else set ete15 or fpte15 = 0
+
+| input:
+|	a0 = points to operand to be normalized
+| output:
+|	L_SCR1{7:5} = operand tag (000 = norm, 100 = denorm)
+|	L_SCR1{4}   = fpte15 or ete15 (0 = exp > $3fff, 1 = exp <=$3fff)
+|	the normalized operand is placed back on the fsave stack
+mk_norm:	
+	clrl	L_SCR1(%a6)
+	bclrb	#sign_bit,LOCAL_EX(%a0)
+	sne	LOCAL_SGN(%a0)	|transform into internal extended format
+
+	cmpib	#0x2c,1+EXC_VEC(%a6) |check if unimp
+	bnes	uns_data	|branch if unsupp
+	bsr	uni_inst	|call if unimp (opclass 0x0)
+	bras	reload
+uns_data:
+	btstb	#direction_bit,CMDREG1B(%a6) |check transfer direction
+	bnes	bit_set		|branch if set (opclass 011)
+	bsr	uns_opx		|call if opclass 0x0
+	bras	reload
+bit_set:
+	bsr	uns_op3		|opclass 011
+reload:
+	cmpw	#0x3fff,LOCAL_EX(%a0) |if exp > $3fff
+	bgts	end_mk		|   fpte15/ete15 already set to 0
+	bsetb	#4,L_SCR1(%a6)	|else set fpte15/ete15 to 1
+|				;calling routine actually sets the 
+|				;value on the stack (along with the 
+|				;tag), since this routine doesn't 
+|				;know if it should set ete15 or fpte15
+|				;ie, it doesn't know if this is the 
+|				;src op or dest op.
+end_mk:
+	bfclr	LOCAL_SGN(%a0){#0:#8}
+	beqs	end_mk_pos
+	bsetb	#sign_bit,LOCAL_EX(%a0) |convert back to IEEE format
+end_mk_pos:
+	rts
+|
+|     CASE opclass 011 unsupp
+|
+uns_op3:
+	bsr	nrm_zero	|normalize till msb = 1 or exp = zero
+	btstb	#7,LOCAL_HI(%a0)	|if msb = 1
+	bnes	no_unfl		|then branch
+set_unfl:
+	orw	#dnrm_tag,L_SCR1(%a6) |set denorm tag
+	bsetb	#unfl_bit,FPSR_EXCEPT(%a6) |set unfl exception bit
+no_unfl:
+	rts
+|
+|     CASE opclass 0x0 unsupp
+|
+uns_opx:
+	bsr	nrm_zero	|normalize the number
+	btstb	#7,LOCAL_HI(%a0)	|check if integer bit (j-bit) is set 
+	beqs	uns_den		|if clear then now have a denorm
+uns_nrm:
+	orb	#norm_tag,L_SCR1(%a6) |set tag to norm
+	rts
+uns_den:
+	orb	#dnrm_tag,L_SCR1(%a6) |set tag to denorm
+	rts
+|
+|     CASE opclass 0x0 unimp
+|
+uni_inst:
+	bsr	nrm_zero
+	btstb	#7,LOCAL_HI(%a0)	|check if integer bit (j-bit) is set 
+	beqs	uni_den		|if clear then now have a denorm
+uni_nrm:
+	orb	#norm_tag,L_SCR1(%a6) |set tag to norm
+	rts
+uni_den:
+	orb	#dnrm_tag,L_SCR1(%a6) |set tag to denorm
+	rts
+
+|
+|	Decimal to binary conversion
+|
+| Special cases of inf and NaNs are completed outside of decbin.  
+| If the input is an snan, the snan bit is not set.
+| 
+| input:
+|	ETEMP(a6)	- points to packed decimal string in memory
+| output:
+|	fp0	- contains packed string converted to extended precision
+|	ETEMP	- same as fp0
+unpack:
+	movew	CMDREG1B(%a6),%d0	|examine command word, looking for fmove's
+	andw	#0x3b,%d0
+	beq	move_unpack	|special handling for fmove: must set FPSR_CC
+
+	movew	ETEMP(%a6),%d0	|get word with inf information
+	bfextu	%d0{#20:#12},%d1	|get exponent into d1
+	cmpiw	#0x0fff,%d1	|test for inf or NaN
+	bnes	try_zero	|if not equal, it is not special
+	bfextu	%d0{#17:#3},%d1	|get SE and y bits into d1
+	cmpiw	#7,%d1		|SE and y bits must be on for special
+	bnes	try_zero	|if not on, it is not special
+|input is of the special cases of inf and NaN
+	tstl	ETEMP_HI(%a6)	|check ms mantissa
+	bnes	fix_nan		|if non-zero, it is a NaN
+	tstl	ETEMP_LO(%a6)	|check ls mantissa
+	bnes	fix_nan		|if non-zero, it is a NaN
+	bra	finish		|special already on stack
+fix_nan:
+	btstb	#signan_bit,ETEMP_HI(%a6) |test for snan
+	bne	finish
+	orl	#snaniop_mask,USER_FPSR(%a6) |always set snan if it is so
+	bra	finish
+try_zero:
+	movew	ETEMP_EX+2(%a6),%d0 |get word 4
+	andiw	#0x000f,%d0	|clear all but last ni(y)bble
+	tstw	%d0		|check for zero.
+	bne	not_spec
+	tstl	ETEMP_HI(%a6)	|check words 3 and 2
+	bne	not_spec
+	tstl	ETEMP_LO(%a6)	|check words 1 and 0
+	bne	not_spec
+	tstl	ETEMP(%a6)	|test sign of the zero
+	bges	pos_zero
+	movel	#0x80000000,ETEMP(%a6) |write neg zero to etemp
+	clrl	ETEMP_HI(%a6)
+	clrl	ETEMP_LO(%a6)
+	bra	finish
+pos_zero:
+	clrl	ETEMP(%a6)
+	clrl	ETEMP_HI(%a6)
+	clrl	ETEMP_LO(%a6)
+	bra	finish
+
+not_spec:
+	fmovemx %fp0-%fp1,-(%a7)	|save fp0 - decbin returns in it
+	bsr	decbin
+	fmovex %fp0,ETEMP(%a6)	|put the unpacked sop in the fsave stack
+	fmovemx (%a7)+,%fp0-%fp1
+	fmovel	#0,%FPSR		|clr fpsr from decbin
+	bra	finish
+
+|
+| Special handling for packed move in:  Same results as all other
+| packed cases, but we must set the FPSR condition codes properly.
+|
+move_unpack:
+	movew	ETEMP(%a6),%d0	|get word with inf information
+	bfextu	%d0{#20:#12},%d1	|get exponent into d1
+	cmpiw	#0x0fff,%d1	|test for inf or NaN
+	bnes	mtry_zero	|if not equal, it is not special
+	bfextu	%d0{#17:#3},%d1	|get SE and y bits into d1
+	cmpiw	#7,%d1		|SE and y bits must be on for special
+	bnes	mtry_zero	|if not on, it is not special
+|input is of the special cases of inf and NaN
+	tstl	ETEMP_HI(%a6)	|check ms mantissa
+	bnes	mfix_nan		|if non-zero, it is a NaN
+	tstl	ETEMP_LO(%a6)	|check ls mantissa
+	bnes	mfix_nan		|if non-zero, it is a NaN
+|input is inf
+	orl	#inf_mask,USER_FPSR(%a6) |set I bit
+	tstl	ETEMP(%a6)	|check sign
+	bge	finish
+	orl	#neg_mask,USER_FPSR(%a6) |set N bit
+	bra	finish		|special already on stack
+mfix_nan:
+	orl	#nan_mask,USER_FPSR(%a6) |set NaN bit
+	moveb	#nan_tag,STAG(%a6)	|set stag to NaN
+	btstb	#signan_bit,ETEMP_HI(%a6) |test for snan
+	bnes	mn_snan
+	orl	#snaniop_mask,USER_FPSR(%a6) |set snan bit
+	btstb	#snan_bit,FPCR_ENABLE(%a6) |test for snan enabled
+	bnes	mn_snan
+	bsetb	#signan_bit,ETEMP_HI(%a6) |force snans to qnans
+mn_snan:
+	tstl	ETEMP(%a6)	|check for sign
+	bge	finish		|if clr, go on
+	orl	#neg_mask,USER_FPSR(%a6) |set N bit
+	bra	finish
+
+mtry_zero:
+	movew	ETEMP_EX+2(%a6),%d0 |get word 4
+	andiw	#0x000f,%d0	|clear all but last ni(y)bble
+	tstw	%d0		|check for zero.
+	bnes	mnot_spec
+	tstl	ETEMP_HI(%a6)	|check words 3 and 2
+	bnes	mnot_spec
+	tstl	ETEMP_LO(%a6)	|check words 1 and 0
+	bnes	mnot_spec
+	tstl	ETEMP(%a6)	|test sign of the zero
+	bges	mpos_zero
+	orl	#neg_mask+z_mask,USER_FPSR(%a6) |set N and Z
+	movel	#0x80000000,ETEMP(%a6) |write neg zero to etemp
+	clrl	ETEMP_HI(%a6)
+	clrl	ETEMP_LO(%a6)
+	bras	finish
+mpos_zero:
+	orl	#z_mask,USER_FPSR(%a6) |set Z
+	clrl	ETEMP(%a6)
+	clrl	ETEMP_HI(%a6)
+	clrl	ETEMP_LO(%a6)
+	bras	finish
+
+mnot_spec:
+	fmovemx %fp0-%fp1,-(%a7)	|save fp0 ,fp1 - decbin returns in fp0
+	bsr	decbin
+	fmovex %fp0,ETEMP(%a6)
+|				;put the unpacked sop in the fsave stack
+	fmovemx (%a7)+,%fp0-%fp1
+
+finish:
+	movew	CMDREG1B(%a6),%d0	|get the command word
+	andw	#0xfbff,%d0	|change the source specifier field to 
+|				;extended (was packed).
+	movew	%d0,CMDREG1B(%a6)	|write command word back to fsave stack
+|				;we need to do this so the 040 will 
+|				;re-execute the inst. without taking 
+|				;another packed trap.
+
+fix_stag:
+|Converted result is now in etemp on fsave stack, now set the source 
+|tag (stag) 
+|	if (ete =$7fff) then INF or NAN
+|		if (etemp = $x.0----0) then
+|			stag = INF
+|		else
+|			stag = NAN
+|	else
+|		if (ete = $0000) then
+|			stag = ZERO
+|		else
+|			stag = NORM
+|
+| Note also that the etemp_15 bit (just right of the stag) must
+| be set accordingly.  
+|
+	movew		ETEMP_EX(%a6),%d1
+	andiw		#0x7fff,%d1   |strip sign
+	cmpw  		#0x7fff,%d1
+	bnes  		z_or_nrm
+	movel		ETEMP_HI(%a6),%d1
+	bnes		is_nan
+	movel		ETEMP_LO(%a6),%d1
+	bnes		is_nan
+is_inf:
+	moveb		#0x40,STAG(%a6)
+	movel		#0x40,%d0
+	rts
+is_nan:
+	moveb		#0x60,STAG(%a6)
+	movel		#0x60,%d0
+	rts
+z_or_nrm:
+	tstw		%d1  
+	bnes		is_nrm
+is_zro:
+| For a zero, set etemp_15
+	moveb		#0x30,STAG(%a6)
+	movel		#0x20,%d0
+	rts
+is_nrm:
+| For a norm, check if the exp <= $3fff; if so, set etemp_15
+	cmpiw		#0x3fff,%d1
+	bles		set_bit15
+	moveb		#0,STAG(%a6)
+	bras		end_is_nrm
+set_bit15:
+	moveb		#0x10,STAG(%a6)
+end_is_nrm:
+	movel		#0,%d0
+end_fix:
+	rts
+ 
+end_get:
+	rts
+	|end
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov with Sam's (original) version
of this