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25 | THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA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