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docs/system/gdb.rst: Add some more heading structure
[qemu/ar7.git] / target / ppc / dfp_helper.c
blob07341a69f5204f5808d0089e0e83e9aa1439462c
1 /*
2 * PowerPC Decimal Floating Point (DPF) emulation helpers for QEMU.
3 *
4 * Copyright (c) 2014 IBM Corporation.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "exec/helper-proto.h"
23
24 #define DECNUMDIGITS 34
25 #include "libdecnumber/decContext.h"
26 #include "libdecnumber/decNumber.h"
27 #include "libdecnumber/dpd/decimal32.h"
28 #include "libdecnumber/dpd/decimal64.h"
29 #include "libdecnumber/dpd/decimal128.h"
30
31
32 static void get_dfp64(ppc_vsr_t *dst, ppc_fprp_t *dfp)
33 {
34 dst->VsrD(1) = dfp->VsrD(0);
35 }
36
37 static void get_dfp128(ppc_vsr_t *dst, ppc_fprp_t *dfp)
38 {
39 dst->VsrD(0) = dfp[0].VsrD(0);
40 dst->VsrD(1) = dfp[1].VsrD(0);
41 }
42
43 static void set_dfp64(ppc_fprp_t *dfp, ppc_vsr_t *src)
44 {
45 dfp->VsrD(0) = src->VsrD(1);
46 }
47
48 static void set_dfp128(ppc_fprp_t *dfp, ppc_vsr_t *src)
49 {
50 dfp[0].VsrD(0) = src->VsrD(0);
51 dfp[1].VsrD(0) = src->VsrD(1);
52 }
53
54 struct PPC_DFP {
55 CPUPPCState *env;
56 ppc_vsr_t vt, va, vb;
57 decNumber t, a, b;
58 decContext context;
59 uint8_t crbf;
60 };
61
62 static void dfp_prepare_rounding_mode(decContext *context, uint64_t fpscr)
63 {
64 enum rounding rnd;
65
66 switch ((fpscr & FP_DRN) >> FPSCR_DRN0) {
67 case 0:
68 rnd = DEC_ROUND_HALF_EVEN;
69 break;
70 case 1:
71 rnd = DEC_ROUND_DOWN;
72 break;
73 case 2:
74 rnd = DEC_ROUND_CEILING;
75 break;
76 case 3:
77 rnd = DEC_ROUND_FLOOR;
78 break;
79 case 4:
80 rnd = DEC_ROUND_HALF_UP;
81 break;
82 case 5:
83 rnd = DEC_ROUND_HALF_DOWN;
84 break;
85 case 6:
86 rnd = DEC_ROUND_UP;
87 break;
88 case 7:
89 rnd = DEC_ROUND_05UP;
90 break;
91 default:
92 g_assert_not_reached();
93 }
94
95 decContextSetRounding(context, rnd);
96 }
97
98 static void dfp_set_round_mode_from_immediate(uint8_t r, uint8_t rmc,
99 struct PPC_DFP *dfp)
100 {
101 enum rounding rnd;
102 if (r == 0) {
103 switch (rmc & 3) {
104 case 0:
105 rnd = DEC_ROUND_HALF_EVEN;
106 break;
107 case 1:
108 rnd = DEC_ROUND_DOWN;
109 break;
110 case 2:
111 rnd = DEC_ROUND_HALF_UP;
112 break;
113 case 3: /* use FPSCR rounding mode */
114 return;
115 default:
116 assert(0); /* cannot get here */
117 }
118 } else { /* r == 1 */
119 switch (rmc & 3) {
120 case 0:
121 rnd = DEC_ROUND_CEILING;
122 break;
123 case 1:
124 rnd = DEC_ROUND_FLOOR;
125 break;
126 case 2:
127 rnd = DEC_ROUND_UP;
128 break;
129 case 3:
130 rnd = DEC_ROUND_HALF_DOWN;
131 break;
132 default:
133 assert(0); /* cannot get here */
134 }
135 }
136 decContextSetRounding(&dfp->context, rnd);
137 }
138
139 static void dfp_prepare_decimal64(struct PPC_DFP *dfp, ppc_fprp_t *a,
140 ppc_fprp_t *b, CPUPPCState *env)
141 {
142 decContextDefault(&dfp->context, DEC_INIT_DECIMAL64);
143 dfp_prepare_rounding_mode(&dfp->context, env->fpscr);
144 dfp->env = env;
145
146 if (a) {
147 get_dfp64(&dfp->va, a);
148 decimal64ToNumber((decimal64 *)&dfp->va.VsrD(1), &dfp->a);
149 } else {
150 dfp->va.VsrD(1) = 0;
151 decNumberZero(&dfp->a);
152 }
153
154 if (b) {
155 get_dfp64(&dfp->vb, b);
156 decimal64ToNumber((decimal64 *)&dfp->vb.VsrD(1), &dfp->b);
157 } else {
158 dfp->vb.VsrD(1) = 0;
159 decNumberZero(&dfp->b);
160 }
161 }
162
163 static void dfp_prepare_decimal128(struct PPC_DFP *dfp, ppc_fprp_t *a,
164 ppc_fprp_t *b, CPUPPCState *env)
165 {
166 decContextDefault(&dfp->context, DEC_INIT_DECIMAL128);
167 dfp_prepare_rounding_mode(&dfp->context, env->fpscr);
168 dfp->env = env;
169
170 if (a) {
171 get_dfp128(&dfp->va, a);
172 decimal128ToNumber((decimal128 *)&dfp->va, &dfp->a);
173 } else {
174 dfp->va.VsrD(0) = dfp->va.VsrD(1) = 0;
175 decNumberZero(&dfp->a);
176 }
177
178 if (b) {
179 get_dfp128(&dfp->vb, b);
180 decimal128ToNumber((decimal128 *)&dfp->vb, &dfp->b);
181 } else {
182 dfp->vb.VsrD(0) = dfp->vb.VsrD(1) = 0;
183 decNumberZero(&dfp->b);
184 }
185 }
186
187 static void dfp_finalize_decimal64(struct PPC_DFP *dfp)
188 {
189 decimal64FromNumber((decimal64 *)&dfp->vt.VsrD(1), &dfp->t, &dfp->context);
190 }
191
192 static void dfp_finalize_decimal128(struct PPC_DFP *dfp)
193 {
194 decimal128FromNumber((decimal128 *)&dfp->vt, &dfp->t, &dfp->context);
195 }
196
197 static void dfp_set_FPSCR_flag(struct PPC_DFP *dfp, uint64_t flag,
198 uint64_t enabled)
199 {
200 dfp->env->fpscr |= (flag | FP_FX);
201 if (dfp->env->fpscr & enabled) {
202 dfp->env->fpscr |= FP_FEX;
203 }
204 }
205
206 static void dfp_set_FPRF_from_FRT_with_context(struct PPC_DFP *dfp,
207 decContext *context)
208 {
209 uint64_t fprf = 0;
210
211 /* construct FPRF */
212 switch (decNumberClass(&dfp->t, context)) {
213 case DEC_CLASS_SNAN:
214 fprf = 0x01;
215 break;
216 case DEC_CLASS_QNAN:
217 fprf = 0x11;
218 break;
219 case DEC_CLASS_NEG_INF:
220 fprf = 0x09;
221 break;
222 case DEC_CLASS_NEG_NORMAL:
223 fprf = 0x08;
224 break;
225 case DEC_CLASS_NEG_SUBNORMAL:
226 fprf = 0x18;
227 break;
228 case DEC_CLASS_NEG_ZERO:
229 fprf = 0x12;
230 break;
231 case DEC_CLASS_POS_ZERO:
232 fprf = 0x02;
233 break;
234 case DEC_CLASS_POS_SUBNORMAL:
235 fprf = 0x14;
236 break;
237 case DEC_CLASS_POS_NORMAL:
238 fprf = 0x04;
239 break;
240 case DEC_CLASS_POS_INF:
241 fprf = 0x05;
242 break;
243 default:
244 assert(0); /* should never get here */
245 }
246 dfp->env->fpscr &= ~FP_FPRF;
247 dfp->env->fpscr |= (fprf << FPSCR_FPRF);
248 }
249
250 static void dfp_set_FPRF_from_FRT(struct PPC_DFP *dfp)
251 {
252 dfp_set_FPRF_from_FRT_with_context(dfp, &dfp->context);
253 }
254
255 static void dfp_set_FPRF_from_FRT_short(struct PPC_DFP *dfp)
256 {
257 decContext shortContext;
258 decContextDefault(&shortContext, DEC_INIT_DECIMAL32);
259 dfp_set_FPRF_from_FRT_with_context(dfp, &shortContext);
260 }
261
262 static void dfp_set_FPRF_from_FRT_long(struct PPC_DFP *dfp)
263 {
264 decContext longContext;
265 decContextDefault(&longContext, DEC_INIT_DECIMAL64);
266 dfp_set_FPRF_from_FRT_with_context(dfp, &longContext);
267 }
268
269 static void dfp_check_for_OX(struct PPC_DFP *dfp)
270 {
271 if (dfp->context.status & DEC_Overflow) {
272 dfp_set_FPSCR_flag(dfp, FP_OX, FP_OE);
273 }
274 }
275
276 static void dfp_check_for_UX(struct PPC_DFP *dfp)
277 {
278 if (dfp->context.status & DEC_Underflow) {
279 dfp_set_FPSCR_flag(dfp, FP_UX, FP_UE);
280 }
281 }
282
283 static void dfp_check_for_XX(struct PPC_DFP *dfp)
284 {
285 if (dfp->context.status & DEC_Inexact) {
286 dfp_set_FPSCR_flag(dfp, FP_XX | FP_FI, FP_XE);
287 }
288 }
289
290 static void dfp_check_for_ZX(struct PPC_DFP *dfp)
291 {
292 if (dfp->context.status & DEC_Division_by_zero) {
293 dfp_set_FPSCR_flag(dfp, FP_ZX, FP_ZE);
294 }
295 }
296
297 static void dfp_check_for_VXSNAN(struct PPC_DFP *dfp)
298 {
299 if (dfp->context.status & DEC_Invalid_operation) {
300 if (decNumberIsSNaN(&dfp->a) || decNumberIsSNaN(&dfp->b)) {
301 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXSNAN, FP_VE);
302 }
303 }
304 }
305
306 static void dfp_check_for_VXSNAN_and_convert_to_QNaN(struct PPC_DFP *dfp)
307 {
308 if (decNumberIsSNaN(&dfp->t)) {
309 dfp->t.bits &= ~DECSNAN;
310 dfp->t.bits |= DECNAN;
311 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXSNAN, FP_VE);
312 }
313 }
314
315 static void dfp_check_for_VXISI(struct PPC_DFP *dfp, int testForSameSign)
316 {
317 if (dfp->context.status & DEC_Invalid_operation) {
318 if (decNumberIsInfinite(&dfp->a) && decNumberIsInfinite(&dfp->b)) {
319 int same = decNumberClass(&dfp->a, &dfp->context) ==
320 decNumberClass(&dfp->b, &dfp->context);
321 if ((same && testForSameSign) || (!same && !testForSameSign)) {
322 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXISI, FP_VE);
323 }
324 }
325 }
326 }
327
328 static void dfp_check_for_VXISI_add(struct PPC_DFP *dfp)
329 {
330 dfp_check_for_VXISI(dfp, 0);
331 }
332
333 static void dfp_check_for_VXISI_subtract(struct PPC_DFP *dfp)
334 {
335 dfp_check_for_VXISI(dfp, 1);
336 }
337
338 static void dfp_check_for_VXIMZ(struct PPC_DFP *dfp)
339 {
340 if (dfp->context.status & DEC_Invalid_operation) {
341 if ((decNumberIsInfinite(&dfp->a) && decNumberIsZero(&dfp->b)) ||
342 (decNumberIsInfinite(&dfp->b) && decNumberIsZero(&dfp->a))) {
343 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXIMZ, FP_VE);
344 }
345 }
346 }
347
348 static void dfp_check_for_VXZDZ(struct PPC_DFP *dfp)
349 {
350 if (dfp->context.status & DEC_Division_undefined) {
351 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXZDZ, FP_VE);
352 }
353 }
354
355 static void dfp_check_for_VXIDI(struct PPC_DFP *dfp)
356 {
357 if (dfp->context.status & DEC_Invalid_operation) {
358 if (decNumberIsInfinite(&dfp->a) && decNumberIsInfinite(&dfp->b)) {
359 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXIDI, FP_VE);
360 }
361 }
362 }
363
364 static void dfp_check_for_VXVC(struct PPC_DFP *dfp)
365 {
366 if (decNumberIsNaN(&dfp->a) || decNumberIsNaN(&dfp->b)) {
367 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXVC, FP_VE);
368 }
369 }
370
371 static void dfp_check_for_VXCVI(struct PPC_DFP *dfp)
372 {
373 if ((dfp->context.status & DEC_Invalid_operation) &&
374 (!decNumberIsSNaN(&dfp->a)) &&
375 (!decNumberIsSNaN(&dfp->b))) {
376 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FP_VE);
377 }
378 }
379
380 static void dfp_set_CRBF_from_T(struct PPC_DFP *dfp)
381 {
382 if (decNumberIsNaN(&dfp->t)) {
383 dfp->crbf = 1;
384 } else if (decNumberIsZero(&dfp->t)) {
385 dfp->crbf = 2;
386 } else if (decNumberIsNegative(&dfp->t)) {
387 dfp->crbf = 8;
388 } else {
389 dfp->crbf = 4;
390 }
391 }
392
393 static void dfp_set_FPCC_from_CRBF(struct PPC_DFP *dfp)
394 {
395 dfp->env->fpscr &= ~FP_FPCC;
396 dfp->env->fpscr |= (dfp->crbf << FPSCR_FPCC);
397 }
398
399 static inline void dfp_makeQNaN(decNumber *dn)
400 {
401 dn->bits &= ~DECSPECIAL;
402 dn->bits |= DECNAN;
403 }
404
405 static inline int dfp_get_digit(decNumber *dn, int n)
406 {
407 assert(DECDPUN == 3);
408 int unit = n / DECDPUN;
409 int dig = n % DECDPUN;
410 switch (dig) {
411 case 0:
412 return dn->lsu[unit] % 10;
413 case 1:
414 return (dn->lsu[unit] / 10) % 10;
415 case 2:
416 return dn->lsu[unit] / 100;
417 }
418 g_assert_not_reached();
419 }
420
421 #define DFP_HELPER_TAB(op, dnop, postprocs, size) \
422 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *a, \
423 ppc_fprp_t *b) \
424 { \
425 struct PPC_DFP dfp; \
426 dfp_prepare_decimal##size(&dfp, a, b, env); \
427 dnop(&dfp.t, &dfp.a, &dfp.b, &dfp.context); \
428 dfp_finalize_decimal##size(&dfp); \
429 postprocs(&dfp); \
430 set_dfp##size(t, &dfp.vt); \
431 }
432
433 static void ADD_PPs(struct PPC_DFP *dfp)
434 {
435 dfp_set_FPRF_from_FRT(dfp);
436 dfp_check_for_OX(dfp);
437 dfp_check_for_UX(dfp);
438 dfp_check_for_XX(dfp);
439 dfp_check_for_VXSNAN(dfp);
440 dfp_check_for_VXISI_add(dfp);
441 }
442
443 DFP_HELPER_TAB(dadd, decNumberAdd, ADD_PPs, 64)
444 DFP_HELPER_TAB(daddq, decNumberAdd, ADD_PPs, 128)
445
446 static void SUB_PPs(struct PPC_DFP *dfp)
447 {
448 dfp_set_FPRF_from_FRT(dfp);
449 dfp_check_for_OX(dfp);
450 dfp_check_for_UX(dfp);
451 dfp_check_for_XX(dfp);
452 dfp_check_for_VXSNAN(dfp);
453 dfp_check_for_VXISI_subtract(dfp);
454 }
455
456 DFP_HELPER_TAB(dsub, decNumberSubtract, SUB_PPs, 64)
457 DFP_HELPER_TAB(dsubq, decNumberSubtract, SUB_PPs, 128)
458
459 static void MUL_PPs(struct PPC_DFP *dfp)
460 {
461 dfp_set_FPRF_from_FRT(dfp);
462 dfp_check_for_OX(dfp);
463 dfp_check_for_UX(dfp);
464 dfp_check_for_XX(dfp);
465 dfp_check_for_VXSNAN(dfp);
466 dfp_check_for_VXIMZ(dfp);
467 }
468
469 DFP_HELPER_TAB(dmul, decNumberMultiply, MUL_PPs, 64)
470 DFP_HELPER_TAB(dmulq, decNumberMultiply, MUL_PPs, 128)
471
472 static void DIV_PPs(struct PPC_DFP *dfp)
473 {
474 dfp_set_FPRF_from_FRT(dfp);
475 dfp_check_for_OX(dfp);
476 dfp_check_for_UX(dfp);
477 dfp_check_for_ZX(dfp);
478 dfp_check_for_XX(dfp);
479 dfp_check_for_VXSNAN(dfp);
480 dfp_check_for_VXZDZ(dfp);
481 dfp_check_for_VXIDI(dfp);
482 }
483
484 DFP_HELPER_TAB(ddiv, decNumberDivide, DIV_PPs, 64)
485 DFP_HELPER_TAB(ddivq, decNumberDivide, DIV_PPs, 128)
486
487 #define DFP_HELPER_BF_AB(op, dnop, postprocs, size) \
488 uint32_t helper_##op(CPUPPCState *env, ppc_fprp_t *a, ppc_fprp_t *b) \
489 { \
490 struct PPC_DFP dfp; \
491 dfp_prepare_decimal##size(&dfp, a, b, env); \
492 dnop(&dfp.t, &dfp.a, &dfp.b, &dfp.context); \
493 dfp_finalize_decimal##size(&dfp); \
494 postprocs(&dfp); \
495 return dfp.crbf; \
496 }
497
498 static void CMPU_PPs(struct PPC_DFP *dfp)
499 {
500 dfp_set_CRBF_from_T(dfp);
501 dfp_set_FPCC_from_CRBF(dfp);
502 dfp_check_for_VXSNAN(dfp);
503 }
504
505 DFP_HELPER_BF_AB(dcmpu, decNumberCompare, CMPU_PPs, 64)
506 DFP_HELPER_BF_AB(dcmpuq, decNumberCompare, CMPU_PPs, 128)
507
508 static void CMPO_PPs(struct PPC_DFP *dfp)
509 {
510 dfp_set_CRBF_from_T(dfp);
511 dfp_set_FPCC_from_CRBF(dfp);
512 dfp_check_for_VXSNAN(dfp);
513 dfp_check_for_VXVC(dfp);
514 }
515
516 DFP_HELPER_BF_AB(dcmpo, decNumberCompare, CMPO_PPs, 64)
517 DFP_HELPER_BF_AB(dcmpoq, decNumberCompare, CMPO_PPs, 128)
518
519 #define DFP_HELPER_TSTDC(op, size) \
520 uint32_t helper_##op(CPUPPCState *env, ppc_fprp_t *a, uint32_t dcm) \
521 { \
522 struct PPC_DFP dfp; \
523 int match = 0; \
524 \
525 dfp_prepare_decimal##size(&dfp, a, 0, env); \
526 \
527 match |= (dcm & 0x20) && decNumberIsZero(&dfp.a); \
528 match |= (dcm & 0x10) && decNumberIsSubnormal(&dfp.a, &dfp.context); \
529 match |= (dcm & 0x08) && decNumberIsNormal(&dfp.a, &dfp.context); \
530 match |= (dcm & 0x04) && decNumberIsInfinite(&dfp.a); \
531 match |= (dcm & 0x02) && decNumberIsQNaN(&dfp.a); \
532 match |= (dcm & 0x01) && decNumberIsSNaN(&dfp.a); \
533 \
534 if (decNumberIsNegative(&dfp.a)) { \
535 dfp.crbf = match ? 0xA : 0x8; \
536 } else { \
537 dfp.crbf = match ? 0x2 : 0x0; \
538 } \
539 \
540 dfp_set_FPCC_from_CRBF(&dfp); \
541 return dfp.crbf; \
542 }
543
544 DFP_HELPER_TSTDC(dtstdc, 64)
545 DFP_HELPER_TSTDC(dtstdcq, 128)
546
547 #define DFP_HELPER_TSTDG(op, size) \
548 uint32_t helper_##op(CPUPPCState *env, ppc_fprp_t *a, uint32_t dcm) \
549 { \
550 struct PPC_DFP dfp; \
551 int minexp, maxexp, nzero_digits, nzero_idx, is_negative, is_zero, \
552 is_extreme_exp, is_subnormal, is_normal, leftmost_is_nonzero, \
553 match; \
554 \
555 dfp_prepare_decimal##size(&dfp, a, 0, env); \
556 \
557 if ((size) == 64) { \
558 minexp = -398; \
559 maxexp = 369; \
560 nzero_digits = 16; \
561 nzero_idx = 5; \
562 } else if ((size) == 128) { \
563 minexp = -6176; \
564 maxexp = 6111; \
565 nzero_digits = 34; \
566 nzero_idx = 11; \
567 } \
568 \
569 is_negative = decNumberIsNegative(&dfp.a); \
570 is_zero = decNumberIsZero(&dfp.a); \
571 is_extreme_exp = (dfp.a.exponent == maxexp) || \
572 (dfp.a.exponent == minexp); \
573 is_subnormal = decNumberIsSubnormal(&dfp.a, &dfp.context); \
574 is_normal = decNumberIsNormal(&dfp.a, &dfp.context); \
575 leftmost_is_nonzero = (dfp.a.digits == nzero_digits) && \
576 (dfp.a.lsu[nzero_idx] != 0); \
577 match = 0; \
578 \
579 match |= (dcm & 0x20) && is_zero && !is_extreme_exp; \
580 match |= (dcm & 0x10) && is_zero && is_extreme_exp; \
581 match |= (dcm & 0x08) && \
582 (is_subnormal || (is_normal && is_extreme_exp)); \
583 match |= (dcm & 0x04) && is_normal && !is_extreme_exp && \
584 !leftmost_is_nonzero; \
585 match |= (dcm & 0x02) && is_normal && !is_extreme_exp && \
586 leftmost_is_nonzero; \
587 match |= (dcm & 0x01) && decNumberIsSpecial(&dfp.a); \
588 \
589 if (is_negative) { \
590 dfp.crbf = match ? 0xA : 0x8; \
591 } else { \
592 dfp.crbf = match ? 0x2 : 0x0; \
593 } \
594 \
595 dfp_set_FPCC_from_CRBF(&dfp); \
596 return dfp.crbf; \
597 }
598
599 DFP_HELPER_TSTDG(dtstdg, 64)
600 DFP_HELPER_TSTDG(dtstdgq, 128)
601
602 #define DFP_HELPER_TSTEX(op, size) \
603 uint32_t helper_##op(CPUPPCState *env, ppc_fprp_t *a, ppc_fprp_t *b) \
604 { \
605 struct PPC_DFP dfp; \
606 int expa, expb, a_is_special, b_is_special; \
607 \
608 dfp_prepare_decimal##size(&dfp, a, b, env); \
609 \
610 expa = dfp.a.exponent; \
611 expb = dfp.b.exponent; \
612 a_is_special = decNumberIsSpecial(&dfp.a); \
613 b_is_special = decNumberIsSpecial(&dfp.b); \
614 \
615 if (a_is_special || b_is_special) { \
616 int atype = a_is_special ? (decNumberIsNaN(&dfp.a) ? 4 : 2) : 1; \
617 int btype = b_is_special ? (decNumberIsNaN(&dfp.b) ? 4 : 2) : 1; \
618 dfp.crbf = (atype ^ btype) ? 0x1 : 0x2; \
619 } else if (expa < expb) { \
620 dfp.crbf = 0x8; \
621 } else if (expa > expb) { \
622 dfp.crbf = 0x4; \
623 } else { \
624 dfp.crbf = 0x2; \
625 } \
626 \
627 dfp_set_FPCC_from_CRBF(&dfp); \
628 return dfp.crbf; \
629 }
630
631 DFP_HELPER_TSTEX(dtstex, 64)
632 DFP_HELPER_TSTEX(dtstexq, 128)
633
634 #define DFP_HELPER_TSTSF(op, size) \
635 uint32_t helper_##op(CPUPPCState *env, ppc_fprp_t *a, ppc_fprp_t *b) \
636 { \
637 struct PPC_DFP dfp; \
638 unsigned k; \
639 ppc_vsr_t va; \
640 \
641 dfp_prepare_decimal##size(&dfp, 0, b, env); \
642 \
643 get_dfp64(&va, a); \
644 k = va.VsrD(1) & 0x3F; \
645 \
646 if (unlikely(decNumberIsSpecial(&dfp.b))) { \
647 dfp.crbf = 1; \
648 } else if (k == 0) { \
649 dfp.crbf = 4; \
650 } else if (unlikely(decNumberIsZero(&dfp.b))) { \
651 /* Zero has no sig digits */ \
652 dfp.crbf = 4; \
653 } else { \
654 unsigned nsd = dfp.b.digits; \
655 if (k < nsd) { \
656 dfp.crbf = 8; \
657 } else if (k > nsd) { \
658 dfp.crbf = 4; \
659 } else { \
660 dfp.crbf = 2; \
661 } \
662 } \
663 \
664 dfp_set_FPCC_from_CRBF(&dfp); \
665 return dfp.crbf; \
666 }
667
668 DFP_HELPER_TSTSF(dtstsf, 64)
669 DFP_HELPER_TSTSF(dtstsfq, 128)
670
671 #define DFP_HELPER_TSTSFI(op, size) \
672 uint32_t helper_##op(CPUPPCState *env, uint32_t a, ppc_fprp_t *b) \
673 { \
674 struct PPC_DFP dfp; \
675 unsigned uim; \
676 \
677 dfp_prepare_decimal##size(&dfp, 0, b, env); \
678 \
679 uim = a & 0x3F; \
680 \
681 if (unlikely(decNumberIsSpecial(&dfp.b))) { \
682 dfp.crbf = 1; \
683 } else if (uim == 0) { \
684 dfp.crbf = 4; \
685 } else if (unlikely(decNumberIsZero(&dfp.b))) { \
686 /* Zero has no sig digits */ \
687 dfp.crbf = 4; \
688 } else { \
689 unsigned nsd = dfp.b.digits; \
690 if (uim < nsd) { \
691 dfp.crbf = 8; \
692 } else if (uim > nsd) { \
693 dfp.crbf = 4; \
694 } else { \
695 dfp.crbf = 2; \
696 } \
697 } \
698 \
699 dfp_set_FPCC_from_CRBF(&dfp); \
700 return dfp.crbf; \
701 }
702
703 DFP_HELPER_TSTSFI(dtstsfi, 64)
704 DFP_HELPER_TSTSFI(dtstsfiq, 128)
705
706 static void QUA_PPs(struct PPC_DFP *dfp)
707 {
708 dfp_set_FPRF_from_FRT(dfp);
709 dfp_check_for_XX(dfp);
710 dfp_check_for_VXSNAN(dfp);
711 dfp_check_for_VXCVI(dfp);
712 }
713
714 static void dfp_quantize(uint8_t rmc, struct PPC_DFP *dfp)
715 {
716 dfp_set_round_mode_from_immediate(0, rmc, dfp);
717 decNumberQuantize(&dfp->t, &dfp->b, &dfp->a, &dfp->context);
718 if (decNumberIsSNaN(&dfp->a)) {
719 dfp->t = dfp->a;
720 dfp_makeQNaN(&dfp->t);
721 } else if (decNumberIsSNaN(&dfp->b)) {
722 dfp->t = dfp->b;
723 dfp_makeQNaN(&dfp->t);
724 } else if (decNumberIsQNaN(&dfp->a)) {
725 dfp->t = dfp->a;
726 } else if (decNumberIsQNaN(&dfp->b)) {
727 dfp->t = dfp->b;
728 }
729 }
730
731 #define DFP_HELPER_QUAI(op, size) \
732 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b, \
733 uint32_t te, uint32_t rmc) \
734 { \
735 struct PPC_DFP dfp; \
736 \
737 dfp_prepare_decimal##size(&dfp, 0, b, env); \
738 \
739 decNumberFromUInt32(&dfp.a, 1); \
740 dfp.a.exponent = (int32_t)((int8_t)(te << 3) >> 3); \
741 \
742 dfp_quantize(rmc, &dfp); \
743 dfp_finalize_decimal##size(&dfp); \
744 QUA_PPs(&dfp); \
745 \
746 set_dfp##size(t, &dfp.vt); \
747 }
748
749 DFP_HELPER_QUAI(dquai, 64)
750 DFP_HELPER_QUAI(dquaiq, 128)
751
752 #define DFP_HELPER_QUA(op, size) \
753 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *a, \
754 ppc_fprp_t *b, uint32_t rmc) \
755 { \
756 struct PPC_DFP dfp; \
757 \
758 dfp_prepare_decimal##size(&dfp, a, b, env); \
759 \
760 dfp_quantize(rmc, &dfp); \
761 dfp_finalize_decimal##size(&dfp); \
762 QUA_PPs(&dfp); \
763 \
764 set_dfp##size(t, &dfp.vt); \
765 }
766
767 DFP_HELPER_QUA(dqua, 64)
768 DFP_HELPER_QUA(dquaq, 128)
769
770 static void _dfp_reround(uint8_t rmc, int32_t ref_sig, int32_t xmax,
771 struct PPC_DFP *dfp)
772 {
773 int msd_orig, msd_rslt;
774
775 if (unlikely((ref_sig == 0) || (dfp->b.digits <= ref_sig))) {
776 dfp->t = dfp->b;
777 if (decNumberIsSNaN(&dfp->b)) {
778 dfp_makeQNaN(&dfp->t);
779 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXSNAN, FPSCR_VE);
780 }
781 return;
782 }
783
784 /* Reround is equivalent to quantizing b with 1**E(n) where */
785 /* n = exp(b) + numDigits(b) - reference_significance. */
786
787 decNumberFromUInt32(&dfp->a, 1);
788 dfp->a.exponent = dfp->b.exponent + dfp->b.digits - ref_sig;
789
790 if (unlikely(dfp->a.exponent > xmax)) {
791 dfp->t.digits = 0;
792 dfp->t.bits &= ~DECNEG;
793 dfp_makeQNaN(&dfp->t);
794 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FPSCR_VE);
795 return;
796 }
797
798 dfp_quantize(rmc, dfp);
799
800 msd_orig = dfp_get_digit(&dfp->b, dfp->b.digits-1);
801 msd_rslt = dfp_get_digit(&dfp->t, dfp->t.digits-1);
802
803 /* If the quantization resulted in rounding up to the next magnitude, */
804 /* then we need to shift the significand and adjust the exponent. */
805
806 if (unlikely((msd_orig == 9) && (msd_rslt == 1))) {
807
808 decNumber negone;
809
810 decNumberFromInt32(&negone, -1);
811 decNumberShift(&dfp->t, &dfp->t, &negone, &dfp->context);
812 dfp->t.exponent++;
813
814 if (unlikely(dfp->t.exponent > xmax)) {
815 dfp_makeQNaN(&dfp->t);
816 dfp->t.digits = 0;
817 dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FP_VE);
818 /* Inhibit XX in this case */
819 decContextClearStatus(&dfp->context, DEC_Inexact);
820 }
821 }
822 }
823
824 #define DFP_HELPER_RRND(op, size) \
825 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *a, \
826 ppc_fprp_t *b, uint32_t rmc) \
827 { \
828 struct PPC_DFP dfp; \
829 ppc_vsr_t va; \
830 int32_t ref_sig; \
831 int32_t xmax = ((size) == 64) ? 369 : 6111; \
832 \
833 dfp_prepare_decimal##size(&dfp, 0, b, env); \
834 \
835 get_dfp64(&va, a); \
836 ref_sig = va.VsrD(1) & 0x3f; \
837 \
838 _dfp_reround(rmc, ref_sig, xmax, &dfp); \
839 dfp_finalize_decimal##size(&dfp); \
840 QUA_PPs(&dfp); \
841 \
842 set_dfp##size(t, &dfp.vt); \
843 }
844
845 DFP_HELPER_RRND(drrnd, 64)
846 DFP_HELPER_RRND(drrndq, 128)
847
848 #define DFP_HELPER_RINT(op, postprocs, size) \
849 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b, \
850 uint32_t r, uint32_t rmc) \
851 { \
852 struct PPC_DFP dfp; \
853 \
854 dfp_prepare_decimal##size(&dfp, 0, b, env); \
855 \
856 dfp_set_round_mode_from_immediate(r, rmc, &dfp); \
857 decNumberToIntegralExact(&dfp.t, &dfp.b, &dfp.context); \
858 dfp_finalize_decimal##size(&dfp); \
859 postprocs(&dfp); \
860 \
861 set_dfp##size(t, &dfp.vt); \
862 }
863
864 static void RINTX_PPs(struct PPC_DFP *dfp)
865 {
866 dfp_set_FPRF_from_FRT(dfp);
867 dfp_check_for_XX(dfp);
868 dfp_check_for_VXSNAN(dfp);
869 }
870
871 DFP_HELPER_RINT(drintx, RINTX_PPs, 64)
872 DFP_HELPER_RINT(drintxq, RINTX_PPs, 128)
873
874 static void RINTN_PPs(struct PPC_DFP *dfp)
875 {
876 dfp_set_FPRF_from_FRT(dfp);
877 dfp_check_for_VXSNAN(dfp);
878 }
879
880 DFP_HELPER_RINT(drintn, RINTN_PPs, 64)
881 DFP_HELPER_RINT(drintnq, RINTN_PPs, 128)
882
883 void helper_dctdp(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b)
884 {
885 struct PPC_DFP dfp;
886 ppc_vsr_t vb;
887 uint32_t b_short;
888
889 get_dfp64(&vb, b);
890 b_short = (uint32_t)vb.VsrD(1);
891
892 dfp_prepare_decimal64(&dfp, 0, 0, env);
893 decimal32ToNumber((decimal32 *)&b_short, &dfp.t);
894 dfp_finalize_decimal64(&dfp);
895 set_dfp64(t, &dfp.vt);
896 dfp_set_FPRF_from_FRT(&dfp);
897 }
898
899 void helper_dctqpq(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b)
900 {
901 struct PPC_DFP dfp;
902 ppc_vsr_t vb;
903 dfp_prepare_decimal128(&dfp, 0, 0, env);
904 get_dfp64(&vb, b);
905 decimal64ToNumber((decimal64 *)&vb.VsrD(1), &dfp.t);
906
907 dfp_check_for_VXSNAN_and_convert_to_QNaN(&dfp);
908 dfp_set_FPRF_from_FRT(&dfp);
909
910 dfp_finalize_decimal128(&dfp);
911 set_dfp128(t, &dfp.vt);
912 }
913
914 void helper_drsp(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b)
915 {
916 struct PPC_DFP dfp;
917 uint32_t t_short = 0;
918 ppc_vsr_t vt;
919 dfp_prepare_decimal64(&dfp, 0, b, env);
920 decimal32FromNumber((decimal32 *)&t_short, &dfp.b, &dfp.context);
921 decimal32ToNumber((decimal32 *)&t_short, &dfp.t);
922
923 dfp_set_FPRF_from_FRT_short(&dfp);
924 dfp_check_for_OX(&dfp);
925 dfp_check_for_UX(&dfp);
926 dfp_check_for_XX(&dfp);
927
928 vt.VsrD(1) = (uint64_t)t_short;
929 set_dfp64(t, &vt);
930 }
931
932 void helper_drdpq(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b)
933 {
934 struct PPC_DFP dfp;
935 dfp_prepare_decimal128(&dfp, 0, b, env);
936 decimal64FromNumber((decimal64 *)&dfp.vt.VsrD(1), &dfp.b, &dfp.context);
937 decimal64ToNumber((decimal64 *)&dfp.vt.VsrD(1), &dfp.t);
938
939 dfp_check_for_VXSNAN_and_convert_to_QNaN(&dfp);
940 dfp_set_FPRF_from_FRT_long(&dfp);
941 dfp_check_for_OX(&dfp);
942 dfp_check_for_UX(&dfp);
943 dfp_check_for_XX(&dfp);
944
945 dfp.vt.VsrD(0) = dfp.vt.VsrD(1) = 0;
946 dfp_finalize_decimal64(&dfp);
947 set_dfp128(t, &dfp.vt);
948 }
949
950 #define DFP_HELPER_CFFIX(op, size) \
951 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b) \
952 { \
953 struct PPC_DFP dfp; \
954 ppc_vsr_t vb; \
955 dfp_prepare_decimal##size(&dfp, 0, b, env); \
956 get_dfp64(&vb, b); \
957 decNumberFromInt64(&dfp.t, (int64_t)vb.VsrD(1)); \
958 dfp_finalize_decimal##size(&dfp); \
959 CFFIX_PPs(&dfp); \
960 \
961 set_dfp##size(t, &dfp.vt); \
962 }
963
964 static void CFFIX_PPs(struct PPC_DFP *dfp)
965 {
966 dfp_set_FPRF_from_FRT(dfp);
967 dfp_check_for_XX(dfp);
968 }
969
970 DFP_HELPER_CFFIX(dcffix, 64)
971 DFP_HELPER_CFFIX(dcffixq, 128)
972
973 #define DFP_HELPER_CTFIX(op, size) \
974 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b) \
975 { \
976 struct PPC_DFP dfp; \
977 dfp_prepare_decimal##size(&dfp, 0, b, env); \
978 \
979 if (unlikely(decNumberIsSpecial(&dfp.b))) { \
980 uint64_t invalid_flags = FP_VX | FP_VXCVI; \
981 if (decNumberIsInfinite(&dfp.b)) { \
982 dfp.vt.VsrD(1) = decNumberIsNegative(&dfp.b) ? INT64_MIN : \
983 INT64_MAX; \
984 } else { /* NaN */ \
985 dfp.vt.VsrD(1) = INT64_MIN; \
986 if (decNumberIsSNaN(&dfp.b)) { \
987 invalid_flags |= FP_VXSNAN; \
988 } \
989 } \
990 dfp_set_FPSCR_flag(&dfp, invalid_flags, FP_VE); \
991 } else if (unlikely(decNumberIsZero(&dfp.b))) { \
992 dfp.vt.VsrD(1) = 0; \
993 } else { \
994 decNumberToIntegralExact(&dfp.b, &dfp.b, &dfp.context); \
995 dfp.vt.VsrD(1) = decNumberIntegralToInt64(&dfp.b, &dfp.context); \
996 if (decContextTestStatus(&dfp.context, DEC_Invalid_operation)) { \
997 dfp.vt.VsrD(1) = decNumberIsNegative(&dfp.b) ? INT64_MIN : \
998 INT64_MAX; \
999 dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FP_VE); \
1000 } else { \
1001 dfp_check_for_XX(&dfp); \
1002 } \
1003 } \
1004 \
1005 set_dfp64(t, &dfp.vt); \
1006 }
1007
1008 DFP_HELPER_CTFIX(dctfix, 64)
1009 DFP_HELPER_CTFIX(dctfixq, 128)
1010
1011 static inline void dfp_set_bcd_digit_64(ppc_vsr_t *t, uint8_t digit,
1012 unsigned n)
1013 {
1014 t->VsrD(1) |= ((uint64_t)(digit & 0xF) << (n << 2));
1015 }
1016
1017 static inline void dfp_set_bcd_digit_128(ppc_vsr_t *t, uint8_t digit,
1018 unsigned n)
1019 {
1020 t->VsrD((n & 0x10) ? 0 : 1) |=
1021 ((uint64_t)(digit & 0xF) << ((n & 15) << 2));
1022 }
1023
1024 static inline void dfp_set_sign_64(ppc_vsr_t *t, uint8_t sgn)
1025 {
1026 t->VsrD(1) <<= 4;
1027 t->VsrD(1) |= (sgn & 0xF);
1028 }
1029
1030 static inline void dfp_set_sign_128(ppc_vsr_t *t, uint8_t sgn)
1031 {
1032 t->VsrD(0) <<= 4;
1033 t->VsrD(0) |= (t->VsrD(1) >> 60);
1034 t->VsrD(1) <<= 4;
1035 t->VsrD(1) |= (sgn & 0xF);
1036 }
1037
1038 #define DFP_HELPER_DEDPD(op, size) \
1039 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b, \
1040 uint32_t sp) \
1041 { \
1042 struct PPC_DFP dfp; \
1043 uint8_t digits[34]; \
1044 int i, N; \
1045 \
1046 dfp_prepare_decimal##size(&dfp, 0, b, env); \
1047 \
1048 decNumberGetBCD(&dfp.b, digits); \
1049 dfp.vt.VsrD(0) = dfp.vt.VsrD(1) = 0; \
1050 N = dfp.b.digits; \
1051 \
1052 for (i = 0; (i < N) && (i < (size)/4); i++) { \
1053 dfp_set_bcd_digit_##size(&dfp.vt, digits[N - i - 1], i); \
1054 } \
1055 \
1056 if (sp & 2) { \
1057 uint8_t sgn; \
1058 \
1059 if (decNumberIsNegative(&dfp.b)) { \
1060 sgn = 0xD; \
1061 } else { \
1062 sgn = ((sp & 1) ? 0xF : 0xC); \
1063 } \
1064 dfp_set_sign_##size(&dfp.vt, sgn); \
1065 } \
1066 \
1067 set_dfp##size(t, &dfp.vt); \
1068 }
1069
1070 DFP_HELPER_DEDPD(ddedpd, 64)
1071 DFP_HELPER_DEDPD(ddedpdq, 128)
1072
1073 static inline uint8_t dfp_get_bcd_digit_64(ppc_vsr_t *t, unsigned n)
1074 {
1075 return t->VsrD(1) >> ((n << 2) & 63) & 15;
1076 }
1077
1078 static inline uint8_t dfp_get_bcd_digit_128(ppc_vsr_t *t, unsigned n)
1079 {
1080 return t->VsrD((n & 0x10) ? 0 : 1) >> ((n << 2) & 63) & 15;
1081 }
1082
1083 #define DFP_HELPER_ENBCD(op, size) \
1084 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b, \
1085 uint32_t s) \
1086 { \
1087 struct PPC_DFP dfp; \
1088 uint8_t digits[32]; \
1089 int n = 0, offset = 0, sgn = 0, nonzero = 0; \
1090 \
1091 dfp_prepare_decimal##size(&dfp, 0, b, env); \
1092 \
1093 decNumberZero(&dfp.t); \
1094 \
1095 if (s) { \
1096 uint8_t sgnNibble = dfp_get_bcd_digit_##size(&dfp.vb, offset++); \
1097 switch (sgnNibble) { \
1098 case 0xD: \
1099 case 0xB: \
1100 sgn = 1; \
1101 break; \
1102 case 0xC: \
1103 case 0xF: \
1104 case 0xA: \
1105 case 0xE: \
1106 sgn = 0; \
1107 break; \
1108 default: \
1109 dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \
1110 return; \
1111 } \
1112 } \
1113 \
1114 while (offset < (size) / 4) { \
1115 n++; \
1116 digits[(size) / 4 - n] = dfp_get_bcd_digit_##size(&dfp.vb, \
1117 offset++); \
1118 if (digits[(size) / 4 - n] > 10) { \
1119 dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \
1120 return; \
1121 } else { \
1122 nonzero |= (digits[(size) / 4 - n] > 0); \
1123 } \
1124 } \
1125 \
1126 if (nonzero) { \
1127 decNumberSetBCD(&dfp.t, digits + ((size) / 4) - n, n); \
1128 } \
1129 \
1130 if (s && sgn) { \
1131 dfp.t.bits |= DECNEG; \
1132 } \
1133 dfp_finalize_decimal##size(&dfp); \
1134 dfp_set_FPRF_from_FRT(&dfp); \
1135 set_dfp##size(t, &dfp.vt); \
1136 }
1137
1138 DFP_HELPER_ENBCD(denbcd, 64)
1139 DFP_HELPER_ENBCD(denbcdq, 128)
1140
1141 #define DFP_HELPER_XEX(op, size) \
1142 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b) \
1143 { \
1144 struct PPC_DFP dfp; \
1145 ppc_vsr_t vt; \
1146 \
1147 dfp_prepare_decimal##size(&dfp, 0, b, env); \
1148 \
1149 if (unlikely(decNumberIsSpecial(&dfp.b))) { \
1150 if (decNumberIsInfinite(&dfp.b)) { \
1151 vt.VsrD(1) = -1; \
1152 } else if (decNumberIsSNaN(&dfp.b)) { \
1153 vt.VsrD(1) = -3; \
1154 } else if (decNumberIsQNaN(&dfp.b)) { \
1155 vt.VsrD(1) = -2; \
1156 } else { \
1157 assert(0); \
1158 } \
1159 set_dfp64(t, &vt); \
1160 } else { \
1161 if ((size) == 64) { \
1162 vt.VsrD(1) = dfp.b.exponent + 398; \
1163 } else if ((size) == 128) { \
1164 vt.VsrD(1) = dfp.b.exponent + 6176; \
1165 } else { \
1166 assert(0); \
1167 } \
1168 set_dfp64(t, &vt); \
1169 } \
1170 }
1171
1172 DFP_HELPER_XEX(dxex, 64)
1173 DFP_HELPER_XEX(dxexq, 128)
1174
1175 static void dfp_set_raw_exp_64(ppc_vsr_t *t, uint64_t raw)
1176 {
1177 t->VsrD(1) &= 0x8003ffffffffffffULL;
1178 t->VsrD(1) |= (raw << (63 - 13));
1179 }
1180
1181 static void dfp_set_raw_exp_128(ppc_vsr_t *t, uint64_t raw)
1182 {
1183 t->VsrD(0) &= 0x80003fffffffffffULL;
1184 t->VsrD(0) |= (raw << (63 - 17));
1185 }
1186
1187 #define DFP_HELPER_IEX(op, size) \
1188 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *a, \
1189 ppc_fprp_t *b) \
1190 { \
1191 struct PPC_DFP dfp; \
1192 uint64_t raw_qnan, raw_snan, raw_inf, max_exp; \
1193 ppc_vsr_t va; \
1194 int bias; \
1195 int64_t exp; \
1196 \
1197 get_dfp64(&va, a); \
1198 exp = (int64_t)va.VsrD(1); \
1199 dfp_prepare_decimal##size(&dfp, 0, b, env); \
1200 \
1201 if ((size) == 64) { \
1202 max_exp = 767; \
1203 raw_qnan = 0x1F00; \
1204 raw_snan = 0x1F80; \
1205 raw_inf = 0x1E00; \
1206 bias = 398; \
1207 } else if ((size) == 128) { \
1208 max_exp = 12287; \
1209 raw_qnan = 0x1f000; \
1210 raw_snan = 0x1f800; \
1211 raw_inf = 0x1e000; \
1212 bias = 6176; \
1213 } else { \
1214 assert(0); \
1215 } \
1216 \
1217 if (unlikely((exp < 0) || (exp > max_exp))) { \
1218 dfp.vt.VsrD(0) = dfp.vb.VsrD(0); \
1219 dfp.vt.VsrD(1) = dfp.vb.VsrD(1); \
1220 if (exp == -1) { \
1221 dfp_set_raw_exp_##size(&dfp.vt, raw_inf); \
1222 } else if (exp == -3) { \
1223 dfp_set_raw_exp_##size(&dfp.vt, raw_snan); \
1224 } else { \
1225 dfp_set_raw_exp_##size(&dfp.vt, raw_qnan); \
1226 } \
1227 } else { \
1228 dfp.t = dfp.b; \
1229 if (unlikely(decNumberIsSpecial(&dfp.t))) { \
1230 dfp.t.bits &= ~DECSPECIAL; \
1231 } \
1232 dfp.t.exponent = exp - bias; \
1233 dfp_finalize_decimal##size(&dfp); \
1234 } \
1235 set_dfp##size(t, &dfp.vt); \
1236 }
1237
1238 DFP_HELPER_IEX(diex, 64)
1239 DFP_HELPER_IEX(diexq, 128)
1240
1241 static void dfp_clear_lmd_from_g5msb(uint64_t *t)
1242 {
1243
1244 /* The most significant 5 bits of the PowerPC DFP format combine bits */
1245 /* from the left-most decimal digit (LMD) and the biased exponent. */
1246 /* This routine clears the LMD bits while preserving the exponent */
1247 /* bits. See "Figure 80: Encoding of bits 0:4 of the G field for */
1248 /* Finite Numbers" in the Power ISA for additional details. */
1249
1250 uint64_t g5msb = (*t >> 58) & 0x1F;
1251
1252 if ((g5msb >> 3) < 3) { /* LMD in [0-7] ? */
1253 *t &= ~(7ULL << 58);
1254 } else {
1255 switch (g5msb & 7) {
1256 case 0:
1257 case 1:
1258 g5msb = 0;
1259 break;
1260 case 2:
1261 case 3:
1262 g5msb = 0x8;
1263 break;
1264 case 4:
1265 case 5:
1266 g5msb = 0x10;
1267 break;
1268 case 6:
1269 g5msb = 0x1E;
1270 break;
1271 case 7:
1272 g5msb = 0x1F;
1273 break;
1274 }
1275
1276 *t &= ~(0x1fULL << 58);
1277 *t |= (g5msb << 58);
1278 }
1279 }
1280
1281 #define DFP_HELPER_SHIFT(op, size, shift_left) \
1282 void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *a, \
1283 uint32_t sh) \
1284 { \
1285 struct PPC_DFP dfp; \
1286 unsigned max_digits = ((size) == 64) ? 16 : 34; \
1287 \
1288 dfp_prepare_decimal##size(&dfp, a, 0, env); \
1289 \
1290 if (sh <= max_digits) { \
1291 \
1292 decNumber shd; \
1293 unsigned special = dfp.a.bits & DECSPECIAL; \
1294 \
1295 if (shift_left) { \
1296 decNumberFromUInt32(&shd, sh); \
1297 } else { \
1298 decNumberFromInt32(&shd, -((int32_t)sh)); \
1299 } \
1300 \
1301 dfp.a.bits &= ~DECSPECIAL; \
1302 decNumberShift(&dfp.t, &dfp.a, &shd, &dfp.context); \
1303 \
1304 dfp.t.bits |= special; \
1305 if (special && (dfp.t.digits >= max_digits)) { \
1306 dfp.t.digits = max_digits - 1; \
1307 } \
1308 \
1309 dfp_finalize_decimal##size(&dfp); \
1310 } else { \
1311 if ((size) == 64) { \
1312 dfp.vt.VsrD(1) = dfp.va.VsrD(1) & \
1313 0xFFFC000000000000ULL; \
1314 dfp_clear_lmd_from_g5msb(&dfp.vt.VsrD(1)); \
1315 } else { \
1316 dfp.vt.VsrD(0) = dfp.va.VsrD(0) & \
1317 0xFFFFC00000000000ULL; \
1318 dfp_clear_lmd_from_g5msb(&dfp.vt.VsrD(0)); \
1319 dfp.vt.VsrD(1) = 0; \
1320 } \
1321 } \
1322 \
1323 set_dfp##size(t, &dfp.vt); \
1324 }
1325
1326 DFP_HELPER_SHIFT(dscli, 64, 1)
1327 DFP_HELPER_SHIFT(dscliq, 128, 1)
1328 DFP_HELPER_SHIFT(dscri, 64, 0)
1329 DFP_HELPER_SHIFT(dscriq, 128, 0)
AR7 emulation for QEMU