fpu.c revision 1.24 1 /* $NetBSD: fpu.c,v 1.24 2005/05/31 00:57:40 christos Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This software was developed by the Computer Systems Engineering group
8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9 * contributed to Berkeley.
10 *
11 * All advertising materials mentioning features or use of this software
12 * must display the following acknowledgement:
13 * This product includes software developed by the University of
14 * California, Lawrence Berkeley Laboratory.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
24 * 3. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 * @(#)fpu.c 8.1 (Berkeley) 6/11/93
41 */
42
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: fpu.c,v 1.24 2005/05/31 00:57:40 christos Exp $");
45
46 #include <sys/param.h>
47 #include <sys/proc.h>
48 #include <sys/signal.h>
49 #include <sys/systm.h>
50 #include <sys/syslog.h>
51 #include <sys/signalvar.h>
52
53 #include <machine/instr.h>
54 #include <machine/reg.h>
55
56 #include <sparc/fpu/fpu_emu.h>
57 #include <sparc/fpu/fpu_extern.h>
58
59 int fpe_debug = 0;
60
61 #ifdef DEBUG
62 /*
63 * Dump a `fpn' structure.
64 */
65 void
66 fpu_dumpfpn(struct fpn *fp)
67 {
68 static const char *class[] = {
69 "SNAN", "QNAN", "ZERO", "NUM", "INF"
70 };
71
72 printf("%s %c.%x %x %x %xE%d", class[fp->fp_class + 2],
73 fp->fp_sign ? '-' : ' ',
74 fp->fp_mant[0], fp->fp_mant[1],
75 fp->fp_mant[2], fp->fp_mant[3],
76 fp->fp_exp);
77 }
78 #endif
79
80 /*
81 * fpu_execute returns the following error numbers (0 = no error):
82 */
83 #define FPE 1 /* take a floating point exception */
84 #define NOTFPU 2 /* not an FPU instruction */
85
86 /*
87 * Translate current exceptions into `first' exception. The
88 * bits go the wrong way for ffs() (0x10 is most important, etc).
89 * There are only 5, so do it the obvious way.
90 */
91 #define X1(x) x
92 #define X2(x) x,x
93 #define X4(x) x,x,x,x
94 #define X8(x) X4(x),X4(x)
95 #define X16(x) X8(x),X8(x)
96
97 static char cx_to_trapx[] = {
98 X1(FSR_NX),
99 X2(FSR_DZ),
100 X4(FSR_UF),
101 X8(FSR_OF),
102 X16(FSR_NV)
103 };
104 static u_char fpu_codes_native[] = {
105 X1(FPE_FLTRES),
106 X2(FPE_FLTDIV),
107 X4(FPE_FLTUND),
108 X8(FPE_FLTOVF),
109 X16(FPE_FLTINV)
110 };
111 #if defined(COMPAT_SUNOS)
112 static u_char fpu_codes_sunos[] = {
113 X1(FPE_FLTINEX_TRAP),
114 X2(FPE_FLTDIV_TRAP),
115 X4(FPE_FLTUND_TRAP),
116 X8(FPE_FLTOVF_TRAP),
117 X16(FPE_FLTOPERR_TRAP)
118 };
119 extern struct emul emul_sunos;
120 #endif /* SUNOS_COMPAT */
121 /* Note: SVR4(Solaris) FPE_* codes happen to be compatible with ours */
122
123 /*
124 * The FPU gave us an exception. Clean up the mess. Note that the
125 * fp queue can only have FPops in it, never load/store FP registers
126 * nor FBfcc instructions. Experiments with `crashme' prove that
127 * unknown FPops do enter the queue, however.
128 */
129 int
130 fpu_cleanup(l, fs)
131 struct lwp *l;
132 #ifndef SUN4U
133 struct fpstate *fs;
134 #else /* SUN4U */
135 struct fpstate64 *fs;
136 #endif /* SUN4U */
137 {
138 int i, fsr = fs->fs_fsr, error;
139 struct proc *p = l->l_proc;
140 union instr instr;
141 struct fpemu fe;
142 u_char *fpu_codes;
143 int code = 0;
144
145 fpu_codes =
146 #ifdef COMPAT_SUNOS
147 (p->p_emul == &emul_sunos) ? fpu_codes_sunos :
148 #endif
149 fpu_codes_native;
150
151 switch ((fsr >> FSR_FTT_SHIFT) & FSR_FTT_MASK) {
152
153 case FSR_TT_NONE:
154 panic("fpu_cleanup: No fault"); /* ??? */
155 break;
156
157 case FSR_TT_IEEE:
158 DPRINTF(FPE_INSN, ("fpu_cleanup: FSR_TT_IEEE\n"));
159 /* XXX missing trap address! */
160 if ((i = fsr & FSR_CX) == 0)
161 panic("fpu ieee trap, but no exception");
162 code = fpu_codes[i - 1];
163 break; /* XXX should return, but queue remains */
164
165 case FSR_TT_UNFIN:
166 DPRINTF(FPE_INSN, ("fpu_cleanup: FSR_TT_UNFIN\n"));
167 #ifdef SUN4U
168 if (fs->fs_qsize == 0) {
169 printf("fpu_cleanup: unfinished fpop");
170 /* The book sez reexecute or emulate. */
171 return (0);
172 }
173 break;
174
175 #endif /* SUN4U */
176 case FSR_TT_UNIMP:
177 DPRINTF(FPE_INSN, ("fpu_cleanup: FSR_TT_UNIMP\n"));
178 if (fs->fs_qsize == 0)
179 panic("fpu_cleanup: unimplemented fpop");
180 break;
181
182 case FSR_TT_SEQ:
183 panic("fpu sequence error");
184 /* NOTREACHED */
185
186 case FSR_TT_HWERR:
187 DPRINTF(FPE_INSN, ("fpu_cleanup: FSR_TT_HWERR\n"));
188 log(LOG_ERR, "fpu hardware error (%s[%d])\n",
189 p->p_comm, p->p_pid);
190 uprintf("%s[%d]: fpu hardware error\n", p->p_comm, p->p_pid);
191 code = SI_NOINFO;
192 goto out;
193
194 default:
195 printf("fsr=0x%x\n", fsr);
196 panic("fpu error");
197 }
198
199 /* emulate the instructions left in the queue */
200 fe.fe_fpstate = fs;
201 for (i = 0; i < fs->fs_qsize; i++) {
202 instr.i_int = fs->fs_queue[i].fq_instr;
203 if (instr.i_any.i_op != IOP_reg ||
204 (instr.i_op3.i_op3 != IOP3_FPop1 &&
205 instr.i_op3.i_op3 != IOP3_FPop2))
206 panic("bogus fpu queue");
207 error = fpu_execute(&fe, instr);
208 if (error == 0)
209 continue;
210
211 switch (error) {
212 case FPE:
213 code = fpu_codes[(fs->fs_fsr & FSR_CX) - 1];
214 break;
215
216 case NOTFPU:
217 #ifdef SUN4U
218 #ifdef DEBUG
219 printf("fpu_cleanup: not an FPU error -- sending SIGILL\n");
220 #endif
221 #endif /* SUN4U */
222 code = SI_NOINFO;
223 break;
224
225 default:
226 panic("fpu_cleanup 3");
227 /* NOTREACHED */
228 }
229 /* XXX should stop here, but queue remains */
230 }
231 out:
232 fs->fs_qsize = 0;
233 return (code);
234 }
235
236 #ifdef notyet
237 /*
238 * If we have no FPU at all (are there any machines like this out
239 * there!?) we have to emulate each instruction, and we need a pointer
240 * to the trapframe so that we can step over them and do FBfcc's.
241 * We know the `queue' is empty, though; we just want to emulate
242 * the instruction at tf->tf_pc.
243 */
244 fpu_emulate(l, tf, fs)
245 struct lwp *l;
246 struct trapframe *tf;
247 #ifndef SUN4U
248 struct fpstate *fs;
249 #else /* SUN4U */
250 struct fpstate64 *fs;
251 #endif /* SUN4U */
252 {
253
254 do {
255 fetch instr from pc
256 decode
257 if (integer instr) {
258 /*
259 * We do this here, rather than earlier, to avoid
260 * losing even more badly than usual.
261 */
262 if (l->l_addr->u_pcb.pcb_uw) {
263 write_user_windows();
264 if (rwindow_save(l))
265 sigexit(l, SIGILL);
266 }
267 if (loadstore) {
268 do_it;
269 pc = npc, npc += 4
270 } else if (fbfcc) {
271 do_annul_stuff;
272 } else
273 return;
274 } else if (fpu instr) {
275 fe.fe_fsr = fs->fs_fsr &= ~FSR_CX;
276 error = fpu_execute(&fe, fs, instr);
277 switch (error) {
278 etc;
279 }
280 } else
281 return;
282 if (want to reschedule)
283 return;
284 } while (error == 0);
285 }
286 #endif
287
288 /*
289 * Execute an FPU instruction (one that runs entirely in the FPU; not
290 * FBfcc or STF, for instance). On return, fe->fe_fs->fs_fsr will be
291 * modified to reflect the setting the hardware would have left.
292 *
293 * Note that we do not catch all illegal opcodes, so you can, for instance,
294 * multiply two integers this way.
295 */
296 int
297 fpu_execute(fe, instr)
298 struct fpemu *fe;
299 union instr instr;
300 {
301 struct fpn *fp;
302 #ifndef SUN4U
303 int opf, rs1, rs2, rd, type, mask, fsr, cx;
304 struct fpstate *fs;
305 #else /* SUN4U */
306 int opf, rs1, rs2, rd, type, mask, fsr, cx, i, cond;
307 struct fpstate64 *fs;
308 #endif /* SUN4U */
309 u_int space[4];
310
311 /*
312 * `Decode' and execute instruction. Start with no exceptions.
313 * The type of any i_opf opcode is in the bottom two bits, so we
314 * squish them out here.
315 */
316 opf = instr.i_opf.i_opf;
317 /*
318 * The low two bits of the opf field for floating point insns usually
319 * correspond to the operation width:
320 *
321 * 0: Invalid
322 * 1: Single precision float
323 * 2: Double precision float
324 * 3: Quad precision float
325 *
326 * The exceptions are the integer to float conversion instructions.
327 *
328 * For double and quad precision, the low bit if the rs or rd field
329 * is actually the high bit of the register number.
330 */
331
332 type = opf & 3;
333 mask = 0x3 >> (3 - type);
334
335 rs1 = instr.i_opf.i_rs1;
336 rs1 = (rs1 & ~mask) | ((rs1 & mask & 0x1) << 5);
337 rs2 = instr.i_opf.i_rs2;
338 rs2 = (rs2 & ~mask) | ((rs2 & mask & 0x1) << 5);
339 rd = instr.i_opf.i_rd;
340 rd = (rd & ~mask) | ((rd & mask & 0x1) << 5);
341 #ifdef DIAGNOSTIC
342 if ((rs1 | rs2 | rd) & mask)
343 /* This may be an FPU insn but it is illegal. */
344 return (NOTFPU);
345 #endif
346 fs = fe->fe_fpstate;
347 fe->fe_fsr = fs->fs_fsr & ~FSR_CX;
348 fe->fe_cx = 0;
349 #ifdef SUN4U
350 /*
351 * Check to see if we're dealing with a fancy cmove and handle
352 * it first.
353 */
354 if (instr.i_op3.i_op3 == IOP3_FPop2 && (opf&0xff0) != (FCMP&0xff0)) {
355 switch (opf >>= 2) {
356 case FMVFC0 >> 2:
357 DPRINTF(FPE_INSN, ("fpu_execute: FMVFC0\n"));
358 cond = (fs->fs_fsr>>FSR_FCC_SHIFT)&FSR_FCC_MASK;
359 if (instr.i_fmovcc.i_cond != cond) return(0); /* success */
360 rs1 = fs->fs_regs[rs2];
361 goto mov;
362 case FMVFC1 >> 2:
363 DPRINTF(FPE_INSN, ("fpu_execute: FMVFC1\n"));
364 cond = (fs->fs_fsr>>FSR_FCC1_SHIFT)&FSR_FCC_MASK;
365 if (instr.i_fmovcc.i_cond != cond) return(0); /* success */
366 rs1 = fs->fs_regs[rs2];
367 goto mov;
368 case FMVFC2 >> 2:
369 DPRINTF(FPE_INSN, ("fpu_execute: FMVFC2\n"));
370 cond = (fs->fs_fsr>>FSR_FCC2_SHIFT)&FSR_FCC_MASK;
371 if (instr.i_fmovcc.i_cond != cond) return(0); /* success */
372 rs1 = fs->fs_regs[rs2];
373 goto mov;
374 case FMVFC3 >> 2:
375 DPRINTF(FPE_INSN, ("fpu_execute: FMVFC3\n"));
376 cond = (fs->fs_fsr>>FSR_FCC3_SHIFT)&FSR_FCC_MASK;
377 if (instr.i_fmovcc.i_cond != cond) return(0); /* success */
378 rs1 = fs->fs_regs[rs2];
379 goto mov;
380 case FMVIC >> 2:
381 /* Presume we're curlwp */
382 DPRINTF(FPE_INSN, ("fpu_execute: FMVIC\n"));
383 cond = (curlwp->l_md.md_tf->tf_tstate>>TSTATE_CCR_SHIFT)&PSR_ICC;
384 if (instr.i_fmovcc.i_cond != cond) return(0); /* success */
385 rs1 = fs->fs_regs[rs2];
386 goto mov;
387 case FMVXC >> 2:
388 /* Presume we're curlwp */
389 DPRINTF(FPE_INSN, ("fpu_execute: FMVXC\n"));
390 cond = (curlwp->l_md.md_tf->tf_tstate>>(TSTATE_CCR_SHIFT+XCC_SHIFT))&PSR_ICC;
391 if (instr.i_fmovcc.i_cond != cond) return(0); /* success */
392 rs1 = fs->fs_regs[rs2];
393 goto mov;
394 case FMVRZ >> 2:
395 /* Presume we're curlwp */
396 DPRINTF(FPE_INSN, ("fpu_execute: FMVRZ\n"));
397 rs1 = instr.i_fmovr.i_rs1;
398 if (rs1 != 0 && (int64_t)curlwp->l_md.md_tf->tf_global[rs1] != 0)
399 return (0); /* success */
400 rs1 = fs->fs_regs[rs2];
401 goto mov;
402 case FMVRLEZ >> 2:
403 /* Presume we're curlwp */
404 DPRINTF(FPE_INSN, ("fpu_execute: FMVRLEZ\n"));
405 rs1 = instr.i_fmovr.i_rs1;
406 if (rs1 != 0 && (int64_t)curlwp->l_md.md_tf->tf_global[rs1] > 0)
407 return (0); /* success */
408 rs1 = fs->fs_regs[rs2];
409 goto mov;
410 case FMVRLZ >> 2:
411 /* Presume we're curlwp */
412 DPRINTF(FPE_INSN, ("fpu_execute: FMVRLZ\n"));
413 rs1 = instr.i_fmovr.i_rs1;
414 if (rs1 == 0 || (int64_t)curlwp->l_md.md_tf->tf_global[rs1] >= 0)
415 return (0); /* success */
416 rs1 = fs->fs_regs[rs2];
417 goto mov;
418 case FMVRNZ >> 2:
419 /* Presume we're curlwp */
420 DPRINTF(FPE_INSN, ("fpu_execute: FMVRNZ\n"));
421 rs1 = instr.i_fmovr.i_rs1;
422 if (rs1 == 0 || (int64_t)curlwp->l_md.md_tf->tf_global[rs1] == 0)
423 return (0); /* success */
424 rs1 = fs->fs_regs[rs2];
425 goto mov;
426 case FMVRGZ >> 2:
427 /* Presume we're curlwp */
428 DPRINTF(FPE_INSN, ("fpu_execute: FMVRGZ\n"));
429 rs1 = instr.i_fmovr.i_rs1;
430 if (rs1 == 0 || (int64_t)curlwp->l_md.md_tf->tf_global[rs1] <= 0)
431 return (0); /* success */
432 rs1 = fs->fs_regs[rs2];
433 goto mov;
434 case FMVRGEZ >> 2:
435 /* Presume we're curlwp */
436 DPRINTF(FPE_INSN, ("fpu_execute: FMVRGEZ\n"));
437 rs1 = instr.i_fmovr.i_rs1;
438 if (rs1 != 0 && (int64_t)curlwp->l_md.md_tf->tf_global[rs1] < 0)
439 return (0); /* success */
440 rs1 = fs->fs_regs[rs2];
441 goto mov;
442 default:
443 DPRINTF(FPE_INSN,
444 ("fpu_execute: unknown v9 FP inst %x opf %x\n",
445 instr.i_int, opf));
446 return (NOTFPU);
447 }
448 }
449 #endif /* SUN4U */
450 switch (opf >>= 2) {
451
452 default:
453 DPRINTF(FPE_INSN,
454 ("fpu_execute: unknown basic FP inst %x opf %x\n",
455 instr.i_int, opf));
456 return (NOTFPU);
457
458 case FMOV >> 2: /* these should all be pretty obvious */
459 DPRINTF(FPE_INSN, ("fpu_execute: FMOV\n"));
460 rs1 = fs->fs_regs[rs2];
461 goto mov;
462
463 case FNEG >> 2:
464 DPRINTF(FPE_INSN, ("fpu_execute: FNEG\n"));
465 rs1 = fs->fs_regs[rs2] ^ (1 << 31);
466 goto mov;
467
468 case FABS >> 2:
469 DPRINTF(FPE_INSN, ("fpu_execute: FABS\n"));
470 rs1 = fs->fs_regs[rs2] & ~(1 << 31);
471 mov:
472 #ifndef SUN4U
473 fs->fs_regs[rd] = rs1;
474 #else /* SUN4U */
475 i = 1<<(type-1);
476 fs->fs_regs[rd++] = rs1;
477 while (--i > 0)
478 fs->fs_regs[rd++] = fs->fs_regs[++rs2];
479 #endif /* SUN4U */
480 fs->fs_fsr = fe->fe_fsr;
481 return (0); /* success */
482
483 case FSQRT >> 2:
484 DPRINTF(FPE_INSN, ("fpu_execute: FSQRT\n"));
485 fpu_explode(fe, &fe->fe_f1, type, rs2);
486 fp = fpu_sqrt(fe);
487 break;
488
489 case FADD >> 2:
490 DPRINTF(FPE_INSN, ("fpu_execute: FADD\n"));
491 fpu_explode(fe, &fe->fe_f1, type, rs1);
492 fpu_explode(fe, &fe->fe_f2, type, rs2);
493 fp = fpu_add(fe);
494 break;
495
496 case FSUB >> 2:
497 DPRINTF(FPE_INSN, ("fpu_execute: FSUB\n"));
498 fpu_explode(fe, &fe->fe_f1, type, rs1);
499 fpu_explode(fe, &fe->fe_f2, type, rs2);
500 fp = fpu_sub(fe);
501 break;
502
503 case FMUL >> 2:
504 DPRINTF(FPE_INSN, ("fpu_execute: FMUL\n"));
505 fpu_explode(fe, &fe->fe_f1, type, rs1);
506 fpu_explode(fe, &fe->fe_f2, type, rs2);
507 fp = fpu_mul(fe);
508 break;
509
510 case FDIV >> 2:
511 DPRINTF(FPE_INSN, ("fpu_execute: FDIV\n"));
512 fpu_explode(fe, &fe->fe_f1, type, rs1);
513 fpu_explode(fe, &fe->fe_f2, type, rs2);
514 fp = fpu_div(fe);
515 break;
516
517 case FCMP >> 2:
518 DPRINTF(FPE_INSN, ("fpu_execute: FCMP\n"));
519 fpu_explode(fe, &fe->fe_f1, type, rs1);
520 fpu_explode(fe, &fe->fe_f2, type, rs2);
521 fpu_compare(fe, 0);
522 goto cmpdone;
523
524 case FCMPE >> 2:
525 DPRINTF(FPE_INSN, ("fpu_execute: FCMPE\n"));
526 fpu_explode(fe, &fe->fe_f1, type, rs1);
527 fpu_explode(fe, &fe->fe_f2, type, rs2);
528 fpu_compare(fe, 1);
529 cmpdone:
530 /*
531 * The only possible exception here is NV; catch it
532 * early and get out, as there is no result register.
533 */
534 cx = fe->fe_cx;
535 fsr = fe->fe_fsr | (cx << FSR_CX_SHIFT);
536 if (cx != 0) {
537 if (fsr & (FSR_NV << FSR_TEM_SHIFT)) {
538 fs->fs_fsr = (fsr & ~FSR_FTT) |
539 (FSR_TT_IEEE << FSR_FTT_SHIFT);
540 return (FPE);
541 }
542 fsr |= FSR_NV << FSR_AX_SHIFT;
543 }
544 fs->fs_fsr = fsr;
545 return (0);
546
547 case FSMULD >> 2:
548 case FDMULX >> 2:
549 DPRINTF(FPE_INSN, ("fpu_execute: FSMULx\n"));
550 if (type == FTYPE_EXT)
551 return (NOTFPU);
552 fpu_explode(fe, &fe->fe_f1, type, rs1);
553 fpu_explode(fe, &fe->fe_f2, type, rs2);
554 type++; /* single to double, or double to quad */
555 fp = fpu_mul(fe);
556 break;
557
558 #ifdef SUN4U
559 case FXTOS >> 2:
560 case FXTOD >> 2:
561 case FXTOQ >> 2:
562 DPRINTF(FPE_INSN, ("fpu_execute: FXTOx\n"));
563 type = FTYPE_LNG;
564 fpu_explode(fe, fp = &fe->fe_f1, type, rs2);
565 type = opf & 3; /* sneaky; depends on instruction encoding */
566 break;
567
568 case FTOX >> 2:
569 DPRINTF(FPE_INSN, ("fpu_execute: FTOX\n"));
570 fpu_explode(fe, fp = &fe->fe_f1, type, rs2);
571 type = FTYPE_LNG;
572 /* Recalculate destination register */
573 rd = instr.i_opf.i_rd;
574 break;
575
576 #endif /* SUN4U */
577 case FTOI >> 2:
578 DPRINTF(FPE_INSN, ("fpu_execute: FTOI\n"));
579 fpu_explode(fe, fp = &fe->fe_f1, type, rs2);
580 type = FTYPE_INT;
581 /* Recalculate destination register */
582 rd = instr.i_opf.i_rd;
583 break;
584
585 case FTOS >> 2:
586 case FTOD >> 2:
587 case FTOQ >> 2:
588 DPRINTF(FPE_INSN, ("fpu_execute: FTOx\n"));
589 fpu_explode(fe, fp = &fe->fe_f1, type, rs2);
590 /* Recalculate rd with correct type info. */
591 type = opf & 3; /* sneaky; depends on instruction encoding */
592 mask = 0x3 >> (3 - type);
593 rd = instr.i_opf.i_rd;
594 rd = (rd & ~mask) | ((rd & mask & 0x1) << 5);
595 break;
596 }
597
598 /*
599 * ALU operation is complete. Collapse the result and then check
600 * for exceptions. If we got any, and they are enabled, do not
601 * alter the destination register, just stop with an exception.
602 * Otherwise set new current exceptions and accrue.
603 */
604 fpu_implode(fe, fp, type, space);
605 cx = fe->fe_cx;
606 fsr = fe->fe_fsr;
607 if (cx != 0) {
608 mask = (fsr >> FSR_TEM_SHIFT) & FSR_TEM_MASK;
609 if (cx & mask) {
610 /* not accrued??? */
611 fs->fs_fsr = (fsr & ~FSR_FTT) |
612 (FSR_TT_IEEE << FSR_FTT_SHIFT) |
613 (cx_to_trapx[(cx & mask) - 1] << FSR_CX_SHIFT);
614 return (FPE);
615 }
616 fsr |= (cx << FSR_CX_SHIFT) | (cx << FSR_AX_SHIFT);
617 }
618 fs->fs_fsr = fsr;
619 DPRINTF(FPE_REG, ("-> %c%d\n", (type == FTYPE_LNG) ? 'x' :
620 ((type == FTYPE_INT) ? 'i' :
621 ((type == FTYPE_SNG) ? 's' :
622 ((type == FTYPE_DBL) ? 'd' :
623 ((type == FTYPE_EXT) ? 'q' : '?')))),
624 rd));
625 fs->fs_regs[rd] = space[0];
626 if (type >= FTYPE_DBL || type == FTYPE_LNG) {
627 fs->fs_regs[rd + 1] = space[1];
628 if (type > FTYPE_DBL) {
629 fs->fs_regs[rd + 2] = space[2];
630 fs->fs_regs[rd + 3] = space[3];
631 }
632 }
633 return (0); /* success */
634 }
635