xref: /openbmc/linux/arch/m68k/fpsp040/util.S (revision e5451c8f8330e03ad3cfa16048b4daf961af434f)
1 |
2 |	util.sa 3.7 7/29/91
3 |
4 |	This file contains routines used by other programs.
5 |
6 |	ovf_res: used by overflow to force the correct
7 |		 result. ovf_r_k, ovf_r_x2, ovf_r_x3 are
8 |		 derivatives of this routine.
9 |	get_fline: get user's opcode word
10 |	g_dfmtou: returns the destination format.
11 |	g_opcls: returns the opclass of the float instruction.
12 |	g_rndpr: returns the rounding precision.
13 |	reg_dest: write byte, word, or long data to Dn
14 |
15 |
16 |		Copyright (C) Motorola, Inc. 1990
17 |			All Rights Reserved
18 |
19 |       For details on the license for this file, please see the
20 |       file, README, in this same directory.
21 
22 |UTIL	idnt    2,1 | Motorola 040 Floating Point Software Package
23 
24 	|section	8
25 
26 #include "fpsp.h"
27 
28 	|xref	mem_read
29 
30 	.global	g_dfmtou
31 	.global	g_opcls
32 	.global	g_rndpr
33 	.global	get_fline
34 	.global	reg_dest
35 
36 |
37 | Final result table for ovf_res. Note that the negative counterparts
38 | are unnecessary as ovf_res always returns the sign separately from
39 | the exponent.
40 |					;+inf
41 EXT_PINF:	.long	0x7fff0000,0x00000000,0x00000000,0x00000000
42 |					;largest +ext
43 EXT_PLRG:	.long	0x7ffe0000,0xffffffff,0xffffffff,0x00000000
44 |					;largest magnitude +sgl in ext
45 SGL_PLRG:	.long	0x407e0000,0xffffff00,0x00000000,0x00000000
46 |					;largest magnitude +dbl in ext
47 DBL_PLRG:	.long	0x43fe0000,0xffffffff,0xfffff800,0x00000000
48 |					;largest -ext
49 
50 tblovfl:
51 	.long	EXT_RN
52 	.long	EXT_RZ
53 	.long	EXT_RM
54 	.long	EXT_RP
55 	.long	SGL_RN
56 	.long	SGL_RZ
57 	.long	SGL_RM
58 	.long	SGL_RP
59 	.long	DBL_RN
60 	.long	DBL_RZ
61 	.long	DBL_RM
62 	.long	DBL_RP
63 	.long	error
64 	.long	error
65 	.long	error
66 	.long	error
67 
68 
69 |
70 |	ovf_r_k --- overflow result calculation
71 |
72 | This entry point is used by kernel_ex.
73 |
74 | This forces the destination precision to be extended
75 |
76 | Input:	operand in ETEMP
77 | Output:	a result is in ETEMP (internal extended format)
78 |
79 	.global	ovf_r_k
80 ovf_r_k:
81 	lea	ETEMP(%a6),%a0	|a0 points to source operand
82 	bclrb	#sign_bit,ETEMP_EX(%a6)
83 	sne	ETEMP_SGN(%a6)	|convert to internal IEEE format
84 
85 |
86 |	ovf_r_x2 --- overflow result calculation
87 |
88 | This entry point used by x_ovfl.  (opclass 0 and 2)
89 |
90 | Input		a0  points to an operand in the internal extended format
91 | Output	a0  points to the result in the internal extended format
92 |
93 | This sets the round precision according to the user's FPCR unless the
94 | instruction is fsgldiv or fsglmul or fsadd, fdadd, fsub, fdsub, fsmul,
95 | fdmul, fsdiv, fddiv, fssqrt, fsmove, fdmove, fsabs, fdabs, fsneg, fdneg.
96 | If the instruction is fsgldiv of fsglmul, the rounding precision must be
97 | extended.  If the instruction is not fsgldiv or fsglmul but a force-
98 | precision instruction, the rounding precision is then set to the force
99 | precision.
100 
101 	.global	ovf_r_x2
102 ovf_r_x2:
103 	btstb	#E3,E_BYTE(%a6)		|check for nu exception
104 	beql	ovf_e1_exc		|it is cu exception
105 ovf_e3_exc:
106 	movew	CMDREG3B(%a6),%d0		|get the command word
107 	andiw	#0x00000060,%d0		|clear all bits except 6 and 5
108 	cmpil	#0x00000040,%d0
109 	beql	ovff_sgl		|force precision is single
110 	cmpil	#0x00000060,%d0
111 	beql	ovff_dbl		|force precision is double
112 	movew	CMDREG3B(%a6),%d0		|get the command word again
113 	andil	#0x7f,%d0			|clear all except operation
114 	cmpil	#0x33,%d0
115 	beql	ovf_fsgl		|fsglmul or fsgldiv
116 	cmpil	#0x30,%d0
117 	beql	ovf_fsgl
118 	bra	ovf_fpcr		|instruction is none of the above
119 |					;use FPCR
120 ovf_e1_exc:
121 	movew	CMDREG1B(%a6),%d0		|get command word
122 	andil	#0x00000044,%d0		|clear all bits except 6 and 2
123 	cmpil	#0x00000040,%d0
124 	beql	ovff_sgl		|the instruction is force single
125 	cmpil	#0x00000044,%d0
126 	beql	ovff_dbl		|the instruction is force double
127 	movew	CMDREG1B(%a6),%d0		|again get the command word
128 	andil	#0x0000007f,%d0		|clear all except the op code
129 	cmpil	#0x00000027,%d0
130 	beql	ovf_fsgl		|fsglmul
131 	cmpil	#0x00000024,%d0
132 	beql	ovf_fsgl		|fsgldiv
133 	bra	ovf_fpcr		|none of the above, use FPCR
134 |
135 |
136 | Inst is either fsgldiv or fsglmul.  Force extended precision.
137 |
138 ovf_fsgl:
139 	clrl	%d0
140 	bra	ovf_res
141 
142 ovff_sgl:
143 	movel	#0x00000001,%d0		|set single
144 	bra	ovf_res
145 ovff_dbl:
146 	movel	#0x00000002,%d0		|set double
147 	bra	ovf_res
148 |
149 | The precision is in the fpcr.
150 |
151 ovf_fpcr:
152 	bfextu	FPCR_MODE(%a6){#0:#2},%d0 |set round precision
153 	bra	ovf_res
154 
155 |
156 |
157 |	ovf_r_x3 --- overflow result calculation
158 |
159 | This entry point used by x_ovfl. (opclass 3 only)
160 |
161 | Input		a0  points to an operand in the internal extended format
162 | Output	a0  points to the result in the internal extended format
163 |
164 | This sets the round precision according to the destination size.
165 |
166 	.global	ovf_r_x3
167 ovf_r_x3:
168 	bsr	g_dfmtou	|get dest fmt in d0{1:0}
169 |				;for fmovout, the destination format
170 |				;is the rounding precision
171 
172 |
173 |	ovf_res --- overflow result calculation
174 |
175 | Input:
176 |	a0	points to operand in internal extended format
177 | Output:
178 |	a0	points to result in internal extended format
179 |
180 	.global	ovf_res
181 ovf_res:
182 	lsll	#2,%d0		|move round precision to d0{3:2}
183 	bfextu	FPCR_MODE(%a6){#2:#2},%d1 |set round mode
184 	orl	%d1,%d0		|index is fmt:mode in d0{3:0}
185 	leal	tblovfl,%a1	|load a1 with table address
186 	movel	%a1@(%d0:l:4),%a1	|use d0 as index to the table
187 	jmp	(%a1)		|go to the correct routine
188 |
189 |case DEST_FMT = EXT
190 |
191 EXT_RN:
192 	leal	EXT_PINF,%a1	|answer is +/- infinity
193 	bsetb	#inf_bit,FPSR_CC(%a6)
194 	bra	set_sign	|now go set the sign
195 EXT_RZ:
196 	leal	EXT_PLRG,%a1	|answer is +/- large number
197 	bra	set_sign	|now go set the sign
198 EXT_RM:
199 	tstb	LOCAL_SGN(%a0)	|if negative overflow
200 	beqs	e_rm_pos
201 e_rm_neg:
202 	leal	EXT_PINF,%a1	|answer is negative infinity
203 	orl	#neginf_mask,USER_FPSR(%a6)
204 	bra	end_ovfr
205 e_rm_pos:
206 	leal	EXT_PLRG,%a1	|answer is large positive number
207 	bra	end_ovfr
208 EXT_RP:
209 	tstb	LOCAL_SGN(%a0)	|if negative overflow
210 	beqs	e_rp_pos
211 e_rp_neg:
212 	leal	EXT_PLRG,%a1	|answer is large negative number
213 	bsetb	#neg_bit,FPSR_CC(%a6)
214 	bra	end_ovfr
215 e_rp_pos:
216 	leal	EXT_PINF,%a1	|answer is positive infinity
217 	bsetb	#inf_bit,FPSR_CC(%a6)
218 	bra	end_ovfr
219 |
220 |case DEST_FMT = DBL
221 |
222 DBL_RN:
223 	leal	EXT_PINF,%a1	|answer is +/- infinity
224 	bsetb	#inf_bit,FPSR_CC(%a6)
225 	bra	set_sign
226 DBL_RZ:
227 	leal	DBL_PLRG,%a1	|answer is +/- large number
228 	bra	set_sign	|now go set the sign
229 DBL_RM:
230 	tstb	LOCAL_SGN(%a0)	|if negative overflow
231 	beqs	d_rm_pos
232 d_rm_neg:
233 	leal	EXT_PINF,%a1	|answer is negative infinity
234 	orl	#neginf_mask,USER_FPSR(%a6)
235 	bra	end_ovfr	|inf is same for all precisions (ext,dbl,sgl)
236 d_rm_pos:
237 	leal	DBL_PLRG,%a1	|answer is large positive number
238 	bra	end_ovfr
239 DBL_RP:
240 	tstb	LOCAL_SGN(%a0)	|if negative overflow
241 	beqs	d_rp_pos
242 d_rp_neg:
243 	leal	DBL_PLRG,%a1	|answer is large negative number
244 	bsetb	#neg_bit,FPSR_CC(%a6)
245 	bra	end_ovfr
246 d_rp_pos:
247 	leal	EXT_PINF,%a1	|answer is positive infinity
248 	bsetb	#inf_bit,FPSR_CC(%a6)
249 	bra	end_ovfr
250 |
251 |case DEST_FMT = SGL
252 |
253 SGL_RN:
254 	leal	EXT_PINF,%a1	|answer is +/-  infinity
255 	bsetb	#inf_bit,FPSR_CC(%a6)
256 	bras	set_sign
257 SGL_RZ:
258 	leal	SGL_PLRG,%a1	|answer is +/- large number
259 	bras	set_sign
260 SGL_RM:
261 	tstb	LOCAL_SGN(%a0)	|if negative overflow
262 	beqs	s_rm_pos
263 s_rm_neg:
264 	leal	EXT_PINF,%a1	|answer is negative infinity
265 	orl	#neginf_mask,USER_FPSR(%a6)
266 	bras	end_ovfr
267 s_rm_pos:
268 	leal	SGL_PLRG,%a1	|answer is large positive number
269 	bras	end_ovfr
270 SGL_RP:
271 	tstb	LOCAL_SGN(%a0)	|if negative overflow
272 	beqs	s_rp_pos
273 s_rp_neg:
274 	leal	SGL_PLRG,%a1	|answer is large negative number
275 	bsetb	#neg_bit,FPSR_CC(%a6)
276 	bras	end_ovfr
277 s_rp_pos:
278 	leal	EXT_PINF,%a1	|answer is positive infinity
279 	bsetb	#inf_bit,FPSR_CC(%a6)
280 	bras	end_ovfr
281 
282 set_sign:
283 	tstb	LOCAL_SGN(%a0)	|if negative overflow
284 	beqs	end_ovfr
285 neg_sign:
286 	bsetb	#neg_bit,FPSR_CC(%a6)
287 
288 end_ovfr:
289 	movew	LOCAL_EX(%a1),LOCAL_EX(%a0) |do not overwrite sign
290 	movel	LOCAL_HI(%a1),LOCAL_HI(%a0)
291 	movel	LOCAL_LO(%a1),LOCAL_LO(%a0)
292 	rts
293 
294 
295 |
296 |	ERROR
297 |
298 error:
299 	rts
300 |
301 |	get_fline --- get f-line opcode of interrupted instruction
302 |
303 |	Returns opcode in the low word of d0.
304 |
305 get_fline:
306 	movel	USER_FPIAR(%a6),%a0	|opcode address
307 	movel	#0,-(%a7)	|reserve a word on the stack
308 	leal	2(%a7),%a1	|point to low word of temporary
309 	movel	#2,%d0		|count
310 	bsrl	mem_read
311 	movel	(%a7)+,%d0
312 	rts
313 |
314 |	g_rndpr --- put rounding precision in d0{1:0}
315 |
316 |	valid return codes are:
317 |		00 - extended
318 |		01 - single
319 |		10 - double
320 |
321 | begin
322 | get rounding precision (cmdreg3b{6:5})
323 | begin
324 |  case	opclass = 011 (move out)
325 |	get destination format - this is the also the rounding precision
326 |
327 |  case	opclass = 0x0
328 |	if E3
329 |	    *case RndPr(from cmdreg3b{6:5} = 11  then RND_PREC = DBL
330 |	    *case RndPr(from cmdreg3b{6:5} = 10  then RND_PREC = SGL
331 |	     case RndPr(from cmdreg3b{6:5} = 00 | 01
332 |		use precision from FPCR{7:6}
333 |			case 00 then RND_PREC = EXT
334 |			case 01 then RND_PREC = SGL
335 |			case 10 then RND_PREC = DBL
336 |	else E1
337 |	     use precision in FPCR{7:6}
338 |	     case 00 then RND_PREC = EXT
339 |	     case 01 then RND_PREC = SGL
340 |	     case 10 then RND_PREC = DBL
341 | end
342 |
343 g_rndpr:
344 	bsr	g_opcls		|get opclass in d0{2:0}
345 	cmpw	#0x0003,%d0	|check for opclass 011
346 	bnes	op_0x0
347 
348 |
349 | For move out instructions (opclass 011) the destination format
350 | is the same as the rounding precision.  Pass results from g_dfmtou.
351 |
352 	bsr	g_dfmtou
353 	rts
354 op_0x0:
355 	btstb	#E3,E_BYTE(%a6)
356 	beql	unf_e1_exc	|branch to e1 underflow
357 unf_e3_exc:
358 	movel	CMDREG3B(%a6),%d0	|rounding precision in d0{10:9}
359 	bfextu	%d0{#9:#2},%d0	|move the rounding prec bits to d0{1:0}
360 	cmpil	#0x2,%d0
361 	beql	unff_sgl	|force precision is single
362 	cmpil	#0x3,%d0		|force precision is double
363 	beql	unff_dbl
364 	movew	CMDREG3B(%a6),%d0	|get the command word again
365 	andil	#0x7f,%d0		|clear all except operation
366 	cmpil	#0x33,%d0
367 	beql	unf_fsgl	|fsglmul or fsgldiv
368 	cmpil	#0x30,%d0
369 	beql	unf_fsgl	|fsgldiv or fsglmul
370 	bra	unf_fpcr
371 unf_e1_exc:
372 	movel	CMDREG1B(%a6),%d0	|get 32 bits off the stack, 1st 16 bits
373 |				;are the command word
374 	andil	#0x00440000,%d0	|clear all bits except bits 6 and 2
375 	cmpil	#0x00400000,%d0
376 	beql	unff_sgl	|force single
377 	cmpil	#0x00440000,%d0	|force double
378 	beql	unff_dbl
379 	movel	CMDREG1B(%a6),%d0	|get the command word again
380 	andil	#0x007f0000,%d0	|clear all bits except the operation
381 	cmpil	#0x00270000,%d0
382 	beql	unf_fsgl	|fsglmul
383 	cmpil	#0x00240000,%d0
384 	beql	unf_fsgl	|fsgldiv
385 	bra	unf_fpcr
386 
387 |
388 | Convert to return format.  The values from cmdreg3b and the return
389 | values are:
390 |	cmdreg3b	return	     precision
391 |	--------	------	     ---------
392 |	  00,01		  0		ext
393 |	   10		  1		sgl
394 |	   11		  2		dbl
395 | Force single
396 |
397 unff_sgl:
398 	movel	#1,%d0		|return 1
399 	rts
400 |
401 | Force double
402 |
403 unff_dbl:
404 	movel	#2,%d0		|return 2
405 	rts
406 |
407 | Force extended
408 |
409 unf_fsgl:
410 	movel	#0,%d0
411 	rts
412 |
413 | Get rounding precision set in FPCR{7:6}.
414 |
415 unf_fpcr:
416 	movel	USER_FPCR(%a6),%d0 |rounding precision bits in d0{7:6}
417 	bfextu	%d0{#24:#2},%d0	|move the rounding prec bits to d0{1:0}
418 	rts
419 |
420 |	g_opcls --- put opclass in d0{2:0}
421 |
422 g_opcls:
423 	btstb	#E3,E_BYTE(%a6)
424 	beqs	opc_1b		|if set, go to cmdreg1b
425 opc_3b:
426 	clrl	%d0		|if E3, only opclass 0x0 is possible
427 	rts
428 opc_1b:
429 	movel	CMDREG1B(%a6),%d0
430 	bfextu	%d0{#0:#3},%d0	|shift opclass bits d0{31:29} to d0{2:0}
431 	rts
432 |
433 |	g_dfmtou --- put destination format in d0{1:0}
434 |
435 |	If E1, the format is from cmdreg1b{12:10}
436 |	If E3, the format is extended.
437 |
438 |	Dest. Fmt.
439 |		extended  010 -> 00
440 |		single    001 -> 01
441 |		double    101 -> 10
442 |
443 g_dfmtou:
444 	btstb	#E3,E_BYTE(%a6)
445 	beqs	op011
446 	clrl	%d0		|if E1, size is always ext
447 	rts
448 op011:
449 	movel	CMDREG1B(%a6),%d0
450 	bfextu	%d0{#3:#3},%d0	|dest fmt from cmdreg1b{12:10}
451 	cmpb	#1,%d0		|check for single
452 	bnes	not_sgl
453 	movel	#1,%d0
454 	rts
455 not_sgl:
456 	cmpb	#5,%d0		|check for double
457 	bnes	not_dbl
458 	movel	#2,%d0
459 	rts
460 not_dbl:
461 	clrl	%d0		|must be extended
462 	rts
463 
464 |
465 |
466 | Final result table for unf_sub. Note that the negative counterparts
467 | are unnecessary as unf_sub always returns the sign separately from
468 | the exponent.
469 |					;+zero
470 EXT_PZRO:	.long	0x00000000,0x00000000,0x00000000,0x00000000
471 |					;+zero
472 SGL_PZRO:	.long	0x3f810000,0x00000000,0x00000000,0x00000000
473 |					;+zero
474 DBL_PZRO:	.long	0x3c010000,0x00000000,0x00000000,0x00000000
475 |					;smallest +ext denorm
476 EXT_PSML:	.long	0x00000000,0x00000000,0x00000001,0x00000000
477 |					;smallest +sgl denorm
478 SGL_PSML:	.long	0x3f810000,0x00000100,0x00000000,0x00000000
479 |					;smallest +dbl denorm
480 DBL_PSML:	.long	0x3c010000,0x00000000,0x00000800,0x00000000
481 |
482 |	UNF_SUB --- underflow result calculation
483 |
484 | Input:
485 |	d0	contains round precision
486 |	a0	points to input operand in the internal extended format
487 |
488 | Output:
489 |	a0	points to correct internal extended precision result.
490 |
491 
492 tblunf:
493 	.long	uEXT_RN
494 	.long	uEXT_RZ
495 	.long	uEXT_RM
496 	.long	uEXT_RP
497 	.long	uSGL_RN
498 	.long	uSGL_RZ
499 	.long	uSGL_RM
500 	.long	uSGL_RP
501 	.long	uDBL_RN
502 	.long	uDBL_RZ
503 	.long	uDBL_RM
504 	.long	uDBL_RP
505 	.long	uDBL_RN
506 	.long	uDBL_RZ
507 	.long	uDBL_RM
508 	.long	uDBL_RP
509 
510 	.global	unf_sub
511 unf_sub:
512 	lsll	#2,%d0		|move round precision to d0{3:2}
513 	bfextu	FPCR_MODE(%a6){#2:#2},%d1 |set round mode
514 	orl	%d1,%d0		|index is fmt:mode in d0{3:0}
515 	leal	tblunf,%a1	|load a1 with table address
516 	movel	%a1@(%d0:l:4),%a1	|use d0 as index to the table
517 	jmp	(%a1)		|go to the correct routine
518 |
519 |case DEST_FMT = EXT
520 |
521 uEXT_RN:
522 	leal	EXT_PZRO,%a1	|answer is +/- zero
523 	bsetb	#z_bit,FPSR_CC(%a6)
524 	bra	uset_sign	|now go set the sign
525 uEXT_RZ:
526 	leal	EXT_PZRO,%a1	|answer is +/- zero
527 	bsetb	#z_bit,FPSR_CC(%a6)
528 	bra	uset_sign	|now go set the sign
529 uEXT_RM:
530 	tstb	LOCAL_SGN(%a0)	|if negative underflow
531 	beqs	ue_rm_pos
532 ue_rm_neg:
533 	leal	EXT_PSML,%a1	|answer is negative smallest denorm
534 	bsetb	#neg_bit,FPSR_CC(%a6)
535 	bra	end_unfr
536 ue_rm_pos:
537 	leal	EXT_PZRO,%a1	|answer is positive zero
538 	bsetb	#z_bit,FPSR_CC(%a6)
539 	bra	end_unfr
540 uEXT_RP:
541 	tstb	LOCAL_SGN(%a0)	|if negative underflow
542 	beqs	ue_rp_pos
543 ue_rp_neg:
544 	leal	EXT_PZRO,%a1	|answer is negative zero
545 	oril	#negz_mask,USER_FPSR(%a6)
546 	bra	end_unfr
547 ue_rp_pos:
548 	leal	EXT_PSML,%a1	|answer is positive smallest denorm
549 	bra	end_unfr
550 |
551 |case DEST_FMT = DBL
552 |
553 uDBL_RN:
554 	leal	DBL_PZRO,%a1	|answer is +/- zero
555 	bsetb	#z_bit,FPSR_CC(%a6)
556 	bra	uset_sign
557 uDBL_RZ:
558 	leal	DBL_PZRO,%a1	|answer is +/- zero
559 	bsetb	#z_bit,FPSR_CC(%a6)
560 	bra	uset_sign	|now go set the sign
561 uDBL_RM:
562 	tstb	LOCAL_SGN(%a0)	|if negative overflow
563 	beqs	ud_rm_pos
564 ud_rm_neg:
565 	leal	DBL_PSML,%a1	|answer is smallest denormalized negative
566 	bsetb	#neg_bit,FPSR_CC(%a6)
567 	bra	end_unfr
568 ud_rm_pos:
569 	leal	DBL_PZRO,%a1	|answer is positive zero
570 	bsetb	#z_bit,FPSR_CC(%a6)
571 	bra	end_unfr
572 uDBL_RP:
573 	tstb	LOCAL_SGN(%a0)	|if negative overflow
574 	beqs	ud_rp_pos
575 ud_rp_neg:
576 	leal	DBL_PZRO,%a1	|answer is negative zero
577 	oril	#negz_mask,USER_FPSR(%a6)
578 	bra	end_unfr
579 ud_rp_pos:
580 	leal	DBL_PSML,%a1	|answer is smallest denormalized negative
581 	bra	end_unfr
582 |
583 |case DEST_FMT = SGL
584 |
585 uSGL_RN:
586 	leal	SGL_PZRO,%a1	|answer is +/- zero
587 	bsetb	#z_bit,FPSR_CC(%a6)
588 	bras	uset_sign
589 uSGL_RZ:
590 	leal	SGL_PZRO,%a1	|answer is +/- zero
591 	bsetb	#z_bit,FPSR_CC(%a6)
592 	bras	uset_sign
593 uSGL_RM:
594 	tstb	LOCAL_SGN(%a0)	|if negative overflow
595 	beqs	us_rm_pos
596 us_rm_neg:
597 	leal	SGL_PSML,%a1	|answer is smallest denormalized negative
598 	bsetb	#neg_bit,FPSR_CC(%a6)
599 	bras	end_unfr
600 us_rm_pos:
601 	leal	SGL_PZRO,%a1	|answer is positive zero
602 	bsetb	#z_bit,FPSR_CC(%a6)
603 	bras	end_unfr
604 uSGL_RP:
605 	tstb	LOCAL_SGN(%a0)	|if negative overflow
606 	beqs	us_rp_pos
607 us_rp_neg:
608 	leal	SGL_PZRO,%a1	|answer is negative zero
609 	oril	#negz_mask,USER_FPSR(%a6)
610 	bras	end_unfr
611 us_rp_pos:
612 	leal	SGL_PSML,%a1	|answer is smallest denormalized positive
613 	bras	end_unfr
614 
615 uset_sign:
616 	tstb	LOCAL_SGN(%a0)	|if negative overflow
617 	beqs	end_unfr
618 uneg_sign:
619 	bsetb	#neg_bit,FPSR_CC(%a6)
620 
621 end_unfr:
622 	movew	LOCAL_EX(%a1),LOCAL_EX(%a0) |be careful not to overwrite sign
623 	movel	LOCAL_HI(%a1),LOCAL_HI(%a0)
624 	movel	LOCAL_LO(%a1),LOCAL_LO(%a0)
625 	rts
626 |
627 |	reg_dest --- write byte, word, or long data to Dn
628 |
629 |
630 | Input:
631 |	L_SCR1: Data
632 |	d1:     data size and dest register number formatted as:
633 |
634 |	32		5    4     3     2     1     0
635 |       -----------------------------------------------
636 |       |        0        |    Size   |  Dest Reg #   |
637 |       -----------------------------------------------
638 |
639 |	Size is:
640 |		0 - Byte
641 |		1 - Word
642 |		2 - Long/Single
643 |
644 pregdst:
645 	.long	byte_d0
646 	.long	byte_d1
647 	.long	byte_d2
648 	.long	byte_d3
649 	.long	byte_d4
650 	.long	byte_d5
651 	.long	byte_d6
652 	.long	byte_d7
653 	.long	word_d0
654 	.long	word_d1
655 	.long	word_d2
656 	.long	word_d3
657 	.long	word_d4
658 	.long	word_d5
659 	.long	word_d6
660 	.long	word_d7
661 	.long	long_d0
662 	.long	long_d1
663 	.long	long_d2
664 	.long	long_d3
665 	.long	long_d4
666 	.long	long_d5
667 	.long	long_d6
668 	.long	long_d7
669 
670 reg_dest:
671 	leal	pregdst,%a0
672 	movel	%a0@(%d1:l:4),%a0
673 	jmp	(%a0)
674 
675 byte_d0:
676 	moveb	L_SCR1(%a6),USER_D0+3(%a6)
677 	rts
678 byte_d1:
679 	moveb	L_SCR1(%a6),USER_D1+3(%a6)
680 	rts
681 byte_d2:
682 	moveb	L_SCR1(%a6),%d2
683 	rts
684 byte_d3:
685 	moveb	L_SCR1(%a6),%d3
686 	rts
687 byte_d4:
688 	moveb	L_SCR1(%a6),%d4
689 	rts
690 byte_d5:
691 	moveb	L_SCR1(%a6),%d5
692 	rts
693 byte_d6:
694 	moveb	L_SCR1(%a6),%d6
695 	rts
696 byte_d7:
697 	moveb	L_SCR1(%a6),%d7
698 	rts
699 word_d0:
700 	movew	L_SCR1(%a6),USER_D0+2(%a6)
701 	rts
702 word_d1:
703 	movew	L_SCR1(%a6),USER_D1+2(%a6)
704 	rts
705 word_d2:
706 	movew	L_SCR1(%a6),%d2
707 	rts
708 word_d3:
709 	movew	L_SCR1(%a6),%d3
710 	rts
711 word_d4:
712 	movew	L_SCR1(%a6),%d4
713 	rts
714 word_d5:
715 	movew	L_SCR1(%a6),%d5
716 	rts
717 word_d6:
718 	movew	L_SCR1(%a6),%d6
719 	rts
720 word_d7:
721 	movew	L_SCR1(%a6),%d7
722 	rts
723 long_d0:
724 	movel	L_SCR1(%a6),USER_D0(%a6)
725 	rts
726 long_d1:
727 	movel	L_SCR1(%a6),USER_D1(%a6)
728 	rts
729 long_d2:
730 	movel	L_SCR1(%a6),%d2
731 	rts
732 long_d3:
733 	movel	L_SCR1(%a6),%d3
734 	rts
735 long_d4:
736 	movel	L_SCR1(%a6),%d4
737 	rts
738 long_d5:
739 	movel	L_SCR1(%a6),%d5
740 	rts
741 long_d6:
742 	movel	L_SCR1(%a6),%d6
743 	rts
744 long_d7:
745 	movel	L_SCR1(%a6),%d7
746 	rts
747 	|end
748