1 |
2 |	do_func.sa 3.4 2/18/91
3 |
4 | Do_func performs the unimplemented operation.  The operation
5 | to be performed is determined from the lower 7 bits of the
6 | extension word (except in the case of fmovecr and fsincos).
7 | The opcode and tag bits form an index into a jump table in
8 | tbldo.sa.  Cases of zero, infinity and NaN are handled in
9 | do_func by forcing the default result.  Normalized and
10 | denormalized (there are no unnormalized numbers at this
11 | point) are passed onto the emulation code.
12 |
13 | CMDREG1B and STAG are extracted from the fsave frame
14 | and combined to form the table index.  The function called
15 | will start with a0 pointing to the ETEMP operand.  Dyadic
16 | functions can find FPTEMP at -12(a0).
17 |
18 | Called functions return their result in fp0.  Sincos returns
19 | sin(x) in fp0 and cos(x) in fp1.
20 |
21 
22 |		Copyright (C) Motorola, Inc. 1990
23 |			All Rights Reserved
24 |
25 |       For details on the license for this file, please see the
26 |       file, README, in this same directory.
27 
28 DO_FUNC:	|idnt    2,1 | Motorola 040 Floating Point Software Package
29 
30 	|section	8
31 
32 #include "fpsp.h"
33 
34 	|xref	t_dz2
35 	|xref	t_operr
36 	|xref	t_inx2
37 	|xref	t_resdnrm
38 	|xref	dst_nan
39 	|xref	src_nan
40 	|xref	nrm_set
41 	|xref	sto_cos
42 
43 	|xref	tblpre
44 	|xref	slognp1,slogn,slog10,slog2
45 	|xref	slognd,slog10d,slog2d
46 	|xref	smod,srem
47 	|xref	sscale
48 	|xref	smovcr
49 
50 PONE:	.long	0x3fff0000,0x80000000,0x00000000	|+1
51 MONE:	.long	0xbfff0000,0x80000000,0x00000000	|-1
52 PZERO:	.long	0x00000000,0x00000000,0x00000000	|+0
53 MZERO:	.long	0x80000000,0x00000000,0x00000000	|-0
54 PINF:	.long	0x7fff0000,0x00000000,0x00000000	|+inf
55 MINF:	.long	0xffff0000,0x00000000,0x00000000	|-inf
56 QNAN:	.long	0x7fff0000,0xffffffff,0xffffffff	|non-signaling nan
57 PPIBY2:  .long	0x3FFF0000,0xC90FDAA2,0x2168C235	|+PI/2
58 MPIBY2:  .long	0xbFFF0000,0xC90FDAA2,0x2168C235	|-PI/2
59 
60 	.global	do_func
61 do_func:
62 	clrb	CU_ONLY(%a6)
63 |
64 | Check for fmovecr.  It does not follow the format of fp gen
65 | unimplemented instructions.  The test is on the upper 6 bits;
66 | if they are $17, the inst is fmovecr.  Call entry smovcr
67 | directly.
68 |
69 	bfextu	CMDREG1B(%a6){#0:#6},%d0 |get opclass and src fields
70 	cmpil	#0x17,%d0		|if op class and size fields are $17,
71 |				;it is FMOVECR; if not, continue
72 	bnes	not_fmovecr
73 	jmp	smovcr		|fmovecr; jmp directly to emulation
74 
75 not_fmovecr:
76 	movew	CMDREG1B(%a6),%d0
77 	andl	#0x7F,%d0
78 	cmpil	#0x38,%d0		|if the extension is >= $38,
79 	bge	serror		|it is illegal
80 	bfextu	STAG(%a6){#0:#3},%d1
81 	lsll	#3,%d0		|make room for STAG
82 	addl	%d1,%d0		|combine for final index into table
83 	leal	tblpre,%a1	|start of monster jump table
84 	movel	(%a1,%d0.w*4),%a1	|real target address
85 	leal	ETEMP(%a6),%a0	|a0 is pointer to src op
86 	movel	USER_FPCR(%a6),%d1
87 	andl	#0xFF,%d1		| discard all but rounding mode/prec
88 	fmovel	#0,%fpcr
89 	jmp	(%a1)
90 |
91 |	ERROR
92 |
93 	.global	serror
94 serror:
95 	st	STORE_FLG(%a6)
96 	rts
97 |
98 | These routines load forced values into fp0.  They are called
99 | by index into tbldo.
100 |
101 | Load a signed zero to fp0 and set inex2/ainex
102 |
103 	.global	snzrinx
104 snzrinx:
105 	btstb	#sign_bit,LOCAL_EX(%a0)	|get sign of source operand
106 	bnes	ld_mzinx	|if negative, branch
107 	bsr	ld_pzero	|bsr so we can return and set inx
108 	bra	t_inx2		|now, set the inx for the next inst
109 ld_mzinx:
110 	bsr	ld_mzero	|if neg, load neg zero, return here
111 	bra	t_inx2		|now, set the inx for the next inst
112 |
113 | Load a signed zero to fp0; do not set inex2/ainex
114 |
115 	.global	szero
116 szero:
117 	btstb	#sign_bit,LOCAL_EX(%a0) |get sign of source operand
118 	bne	ld_mzero	|if neg, load neg zero
119 	bra	ld_pzero	|load positive zero
120 |
121 | Load a signed infinity to fp0; do not set inex2/ainex
122 |
123 	.global	sinf
124 sinf:
125 	btstb	#sign_bit,LOCAL_EX(%a0)	|get sign of source operand
126 	bne	ld_minf			|if negative branch
127 	bra	ld_pinf
128 |
129 | Load a signed one to fp0; do not set inex2/ainex
130 |
131 	.global	sone
132 sone:
133 	btstb	#sign_bit,LOCAL_EX(%a0)	|check sign of source
134 	bne	ld_mone
135 	bra	ld_pone
136 |
137 | Load a signed pi/2 to fp0; do not set inex2/ainex
138 |
139 	.global	spi_2
140 spi_2:
141 	btstb	#sign_bit,LOCAL_EX(%a0)	|check sign of source
142 	bne	ld_mpi2
143 	bra	ld_ppi2
144 |
145 | Load either a +0 or +inf for plus/minus operand
146 |
147 	.global	szr_inf
148 szr_inf:
149 	btstb	#sign_bit,LOCAL_EX(%a0)	|check sign of source
150 	bne	ld_pzero
151 	bra	ld_pinf
152 |
153 | Result is either an operr or +inf for plus/minus operand
154 | [Used by slogn, slognp1, slog10, and slog2]
155 |
156 	.global	sopr_inf
157 sopr_inf:
158 	btstb	#sign_bit,LOCAL_EX(%a0)	|check sign of source
159 	bne	t_operr
160 	bra	ld_pinf
161 |
162 |	FLOGNP1
163 |
164 	.global	sslognp1
165 sslognp1:
166 	fmovemx (%a0),%fp0-%fp0
167 	fcmpb	#-1,%fp0
168 	fbgt	slognp1
169 	fbeq	t_dz2		|if = -1, divide by zero exception
170 	fmovel	#0,%FPSR		|clr N flag
171 	bra	t_operr		|take care of operands < -1
172 |
173 |	FETOXM1
174 |
175 	.global	setoxm1i
176 setoxm1i:
177 	btstb	#sign_bit,LOCAL_EX(%a0)	|check sign of source
178 	bne	ld_mone
179 	bra	ld_pinf
180 |
181 |	FLOGN
182 |
183 | Test for 1.0 as an input argument, returning +zero.  Also check
184 | the sign and return operr if negative.
185 |
186 	.global	sslogn
187 sslogn:
188 	btstb	#sign_bit,LOCAL_EX(%a0)
189 	bne	t_operr		|take care of operands < 0
190 	cmpiw	#0x3fff,LOCAL_EX(%a0) |test for 1.0 input
191 	bne	slogn
192 	cmpil	#0x80000000,LOCAL_HI(%a0)
193 	bne	slogn
194 	tstl	LOCAL_LO(%a0)
195 	bne	slogn
196 	fmovex	PZERO,%fp0
197 	rts
198 
199 	.global	sslognd
200 sslognd:
201 	btstb	#sign_bit,LOCAL_EX(%a0)
202 	beq	slognd
203 	bra	t_operr		|take care of operands < 0
204 
205 |
206 |	FLOG10
207 |
208 	.global	sslog10
209 sslog10:
210 	btstb	#sign_bit,LOCAL_EX(%a0)
211 	bne	t_operr		|take care of operands < 0
212 	cmpiw	#0x3fff,LOCAL_EX(%a0) |test for 1.0 input
213 	bne	slog10
214 	cmpil	#0x80000000,LOCAL_HI(%a0)
215 	bne	slog10
216 	tstl	LOCAL_LO(%a0)
217 	bne	slog10
218 	fmovex	PZERO,%fp0
219 	rts
220 
221 	.global	sslog10d
222 sslog10d:
223 	btstb	#sign_bit,LOCAL_EX(%a0)
224 	beq	slog10d
225 	bra	t_operr		|take care of operands < 0
226 
227 |
228 |	FLOG2
229 |
230 	.global	sslog2
231 sslog2:
232 	btstb	#sign_bit,LOCAL_EX(%a0)
233 	bne	t_operr		|take care of operands < 0
234 	cmpiw	#0x3fff,LOCAL_EX(%a0) |test for 1.0 input
235 	bne	slog2
236 	cmpil	#0x80000000,LOCAL_HI(%a0)
237 	bne	slog2
238 	tstl	LOCAL_LO(%a0)
239 	bne	slog2
240 	fmovex	PZERO,%fp0
241 	rts
242 
243 	.global	sslog2d
244 sslog2d:
245 	btstb	#sign_bit,LOCAL_EX(%a0)
246 	beq	slog2d
247 	bra	t_operr		|take care of operands < 0
248 
249 |
250 |	FMOD
251 |
252 pmodt:
253 |				;$21 fmod
254 |				;dtag,stag
255 	.long	smod		|  00,00  norm,norm = normal
256 	.long	smod_oper	|  00,01  norm,zero = nan with operr
257 	.long	smod_fpn	|  00,10  norm,inf  = fpn
258 	.long	smod_snan	|  00,11  norm,nan  = nan
259 	.long	smod_zro	|  01,00  zero,norm = +-zero
260 	.long	smod_oper	|  01,01  zero,zero = nan with operr
261 	.long	smod_zro	|  01,10  zero,inf  = +-zero
262 	.long	smod_snan	|  01,11  zero,nan  = nan
263 	.long	smod_oper	|  10,00  inf,norm  = nan with operr
264 	.long	smod_oper	|  10,01  inf,zero  = nan with operr
265 	.long	smod_oper	|  10,10  inf,inf   = nan with operr
266 	.long	smod_snan	|  10,11  inf,nan   = nan
267 	.long	smod_dnan	|  11,00  nan,norm  = nan
268 	.long	smod_dnan	|  11,01  nan,zero  = nan
269 	.long	smod_dnan	|  11,10  nan,inf   = nan
270 	.long	smod_dnan	|  11,11  nan,nan   = nan
271 
272 	.global	pmod
273 pmod:
274 	clrb	FPSR_QBYTE(%a6) | clear quotient field
275 	bfextu	STAG(%a6){#0:#3},%d0 |stag = d0
276 	bfextu	DTAG(%a6){#0:#3},%d1 |dtag = d1
277 
278 |
279 | Alias extended denorms to norms for the jump table.
280 |
281 	bclrl	#2,%d0
282 	bclrl	#2,%d1
283 
284 	lslb	#2,%d1
285 	orb	%d0,%d1		|d1{3:2} = dtag, d1{1:0} = stag
286 |				;Tag values:
287 |				;00 = norm or denorm
288 |				;01 = zero
289 |				;10 = inf
290 |				;11 = nan
291 	lea	pmodt,%a1
292 	movel	(%a1,%d1.w*4),%a1
293 	jmp	(%a1)
294 
295 smod_snan:
296 	bra	src_nan
297 smod_dnan:
298 	bra	dst_nan
299 smod_oper:
300 	bra	t_operr
301 smod_zro:
302 	moveb	ETEMP(%a6),%d1	|get sign of src op
303 	moveb	FPTEMP(%a6),%d0	|get sign of dst op
304 	eorb	%d0,%d1		|get exor of sign bits
305 	btstl	#7,%d1		|test for sign
306 	beqs	smod_zsn	|if clr, do not set sign big
307 	bsetb	#q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
308 smod_zsn:
309 	btstl	#7,%d0		|test if + or -
310 	beq	ld_pzero	|if pos then load +0
311 	bra	ld_mzero	|else neg load -0
312 
313 smod_fpn:
314 	moveb	ETEMP(%a6),%d1	|get sign of src op
315 	moveb	FPTEMP(%a6),%d0	|get sign of dst op
316 	eorb	%d0,%d1		|get exor of sign bits
317 	btstl	#7,%d1		|test for sign
318 	beqs	smod_fsn	|if clr, do not set sign big
319 	bsetb	#q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
320 smod_fsn:
321 	tstb	DTAG(%a6)	|filter out denormal destination case
322 	bpls	smod_nrm	|
323 	leal	FPTEMP(%a6),%a0	|a0<- addr(FPTEMP)
324 	bra	t_resdnrm	|force UNFL(but exact) result
325 smod_nrm:
326 	fmovel USER_FPCR(%a6),%fpcr |use user's rmode and precision
327 	fmovex FPTEMP(%a6),%fp0	|return dest to fp0
328 	rts
329 
330 |
331 |	FREM
332 |
333 premt:
334 |				;$25 frem
335 |				;dtag,stag
336 	.long	srem		|  00,00  norm,norm = normal
337 	.long	srem_oper	|  00,01  norm,zero = nan with operr
338 	.long	srem_fpn	|  00,10  norm,inf  = fpn
339 	.long	srem_snan	|  00,11  norm,nan  = nan
340 	.long	srem_zro	|  01,00  zero,norm = +-zero
341 	.long	srem_oper	|  01,01  zero,zero = nan with operr
342 	.long	srem_zro	|  01,10  zero,inf  = +-zero
343 	.long	srem_snan	|  01,11  zero,nan  = nan
344 	.long	srem_oper	|  10,00  inf,norm  = nan with operr
345 	.long	srem_oper	|  10,01  inf,zero  = nan with operr
346 	.long	srem_oper	|  10,10  inf,inf   = nan with operr
347 	.long	srem_snan	|  10,11  inf,nan   = nan
348 	.long	srem_dnan	|  11,00  nan,norm  = nan
349 	.long	srem_dnan	|  11,01  nan,zero  = nan
350 	.long	srem_dnan	|  11,10  nan,inf   = nan
351 	.long	srem_dnan	|  11,11  nan,nan   = nan
352 
353 	.global	prem
354 prem:
355 	clrb	FPSR_QBYTE(%a6)   |clear quotient field
356 	bfextu	STAG(%a6){#0:#3},%d0 |stag = d0
357 	bfextu	DTAG(%a6){#0:#3},%d1 |dtag = d1
358 |
359 | Alias extended denorms to norms for the jump table.
360 |
361 	bclr	#2,%d0
362 	bclr	#2,%d1
363 
364 	lslb	#2,%d1
365 	orb	%d0,%d1		|d1{3:2} = dtag, d1{1:0} = stag
366 |				;Tag values:
367 |				;00 = norm or denorm
368 |				;01 = zero
369 |				;10 = inf
370 |				;11 = nan
371 	lea	premt,%a1
372 	movel	(%a1,%d1.w*4),%a1
373 	jmp	(%a1)
374 
375 srem_snan:
376 	bra	src_nan
377 srem_dnan:
378 	bra	dst_nan
379 srem_oper:
380 	bra	t_operr
381 srem_zro:
382 	moveb	ETEMP(%a6),%d1	|get sign of src op
383 	moveb	FPTEMP(%a6),%d0	|get sign of dst op
384 	eorb	%d0,%d1		|get exor of sign bits
385 	btstl	#7,%d1		|test for sign
386 	beqs	srem_zsn	|if clr, do not set sign big
387 	bsetb	#q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
388 srem_zsn:
389 	btstl	#7,%d0		|test if + or -
390 	beq	ld_pzero	|if pos then load +0
391 	bra	ld_mzero	|else neg load -0
392 
393 srem_fpn:
394 	moveb	ETEMP(%a6),%d1	|get sign of src op
395 	moveb	FPTEMP(%a6),%d0	|get sign of dst op
396 	eorb	%d0,%d1		|get exor of sign bits
397 	btstl	#7,%d1		|test for sign
398 	beqs	srem_fsn	|if clr, do not set sign big
399 	bsetb	#q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
400 srem_fsn:
401 	tstb	DTAG(%a6)	|filter out denormal destination case
402 	bpls	srem_nrm	|
403 	leal	FPTEMP(%a6),%a0	|a0<- addr(FPTEMP)
404 	bra	t_resdnrm	|force UNFL(but exact) result
405 srem_nrm:
406 	fmovel USER_FPCR(%a6),%fpcr |use user's rmode and precision
407 	fmovex FPTEMP(%a6),%fp0	|return dest to fp0
408 	rts
409 |
410 |	FSCALE
411 |
412 pscalet:
413 |				;$26 fscale
414 |				;dtag,stag
415 	.long	sscale		|  00,00  norm,norm = result
416 	.long	sscale		|  00,01  norm,zero = fpn
417 	.long	scl_opr		|  00,10  norm,inf  = nan with operr
418 	.long	scl_snan	|  00,11  norm,nan  = nan
419 	.long	scl_zro		|  01,00  zero,norm = +-zero
420 	.long	scl_zro		|  01,01  zero,zero = +-zero
421 	.long	scl_opr		|  01,10  zero,inf  = nan with operr
422 	.long	scl_snan	|  01,11  zero,nan  = nan
423 	.long	scl_inf		|  10,00  inf,norm  = +-inf
424 	.long	scl_inf		|  10,01  inf,zero  = +-inf
425 	.long	scl_opr		|  10,10  inf,inf   = nan with operr
426 	.long	scl_snan	|  10,11  inf,nan   = nan
427 	.long	scl_dnan	|  11,00  nan,norm  = nan
428 	.long	scl_dnan	|  11,01  nan,zero  = nan
429 	.long	scl_dnan	|  11,10  nan,inf   = nan
430 	.long	scl_dnan	|  11,11  nan,nan   = nan
431 
432 	.global	pscale
433 pscale:
434 	bfextu	STAG(%a6){#0:#3},%d0 |stag in d0
435 	bfextu	DTAG(%a6){#0:#3},%d1 |dtag in d1
436 	bclrl	#2,%d0		|alias  denorm into norm
437 	bclrl	#2,%d1		|alias  denorm into norm
438 	lslb	#2,%d1
439 	orb	%d0,%d1		|d1{4:2} = dtag, d1{1:0} = stag
440 |				;dtag values     stag values:
441 |				;000 = norm      00 = norm
442 |				;001 = zero	 01 = zero
443 |				;010 = inf	 10 = inf
444 |				;011 = nan	 11 = nan
445 |				;100 = dnrm
446 |
447 |
448 	leal	pscalet,%a1	|load start of jump table
449 	movel	(%a1,%d1.w*4),%a1	|load a1 with label depending on tag
450 	jmp	(%a1)		|go to the routine
451 
452 scl_opr:
453 	bra	t_operr
454 
455 scl_dnan:
456 	bra	dst_nan
457 
458 scl_zro:
459 	btstb	#sign_bit,FPTEMP_EX(%a6)	|test if + or -
460 	beq	ld_pzero		|if pos then load +0
461 	bra	ld_mzero		|if neg then load -0
462 scl_inf:
463 	btstb	#sign_bit,FPTEMP_EX(%a6)	|test if + or -
464 	beq	ld_pinf			|if pos then load +inf
465 	bra	ld_minf			|else neg load -inf
466 scl_snan:
467 	bra	src_nan
468 |
469 |	FSINCOS
470 |
471 	.global	ssincosz
472 ssincosz:
473 	btstb	#sign_bit,ETEMP(%a6)	|get sign
474 	beqs	sincosp
475 	fmovex	MZERO,%fp0
476 	bras	sincoscom
477 sincosp:
478 	fmovex PZERO,%fp0
479 sincoscom:
480 	fmovemx PONE,%fp1-%fp1	|do not allow FPSR to be affected
481 	bra	sto_cos		|store cosine result
482 
483 	.global	ssincosi
484 ssincosi:
485 	fmovex QNAN,%fp1	|load NAN
486 	bsr	sto_cos		|store cosine result
487 	fmovex QNAN,%fp0	|load NAN
488 	bra	t_operr
489 
490 	.global	ssincosnan
491 ssincosnan:
492 	movel	ETEMP_EX(%a6),FP_SCR1(%a6)
493 	movel	ETEMP_HI(%a6),FP_SCR1+4(%a6)
494 	movel	ETEMP_LO(%a6),FP_SCR1+8(%a6)
495 	bsetb	#signan_bit,FP_SCR1+4(%a6)
496 	fmovemx FP_SCR1(%a6),%fp1-%fp1
497 	bsr	sto_cos
498 	bra	src_nan
499 |
500 | This code forces default values for the zero, inf, and nan cases
501 | in the transcendentals code.  The CC bits must be set in the
502 | stacked FPSR to be correctly reported.
503 |
504 |**Returns +PI/2
505 	.global	ld_ppi2
506 ld_ppi2:
507 	fmovex PPIBY2,%fp0		|load +pi/2
508 	bra	t_inx2			|set inex2 exc
509 
510 |**Returns -PI/2
511 	.global	ld_mpi2
512 ld_mpi2:
513 	fmovex MPIBY2,%fp0		|load -pi/2
514 	orl	#neg_mask,USER_FPSR(%a6)	|set N bit
515 	bra	t_inx2			|set inex2 exc
516 
517 |**Returns +inf
518 	.global	ld_pinf
519 ld_pinf:
520 	fmovex PINF,%fp0		|load +inf
521 	orl	#inf_mask,USER_FPSR(%a6)	|set I bit
522 	rts
523 
524 |**Returns -inf
525 	.global	ld_minf
526 ld_minf:
527 	fmovex MINF,%fp0		|load -inf
528 	orl	#neg_mask+inf_mask,USER_FPSR(%a6)	|set N and I bits
529 	rts
530 
531 |**Returns +1
532 	.global	ld_pone
533 ld_pone:
534 	fmovex PONE,%fp0		|load +1
535 	rts
536 
537 |**Returns -1
538 	.global	ld_mone
539 ld_mone:
540 	fmovex MONE,%fp0		|load -1
541 	orl	#neg_mask,USER_FPSR(%a6)	|set N bit
542 	rts
543 
544 |**Returns +0
545 	.global	ld_pzero
546 ld_pzero:
547 	fmovex PZERO,%fp0		|load +0
548 	orl	#z_mask,USER_FPSR(%a6)	|set Z bit
549 	rts
550 
551 |**Returns -0
552 	.global	ld_mzero
553 ld_mzero:
554 	fmovex MZERO,%fp0		|load -0
555 	orl	#neg_mask+z_mask,USER_FPSR(%a6)	|set N and Z bits
556 	rts
557 
558 	|end
559