1 /* 2 * ARM VFP floating-point operations 3 * 4 * Copyright (c) 2003 Fabrice Bellard 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 #include "internals.h" 24 #ifdef CONFIG_TCG 25 #include "qemu/log.h" 26 #include "fpu/softfloat.h" 27 #endif 28 29 /* VFP support. We follow the convention used for VFP instructions: 30 Single precision routines have a "s" suffix, double precision a 31 "d" suffix. */ 32 33 #ifdef CONFIG_TCG 34 35 /* Convert host exception flags to vfp form. */ 36 static inline int vfp_exceptbits_from_host(int host_bits) 37 { 38 int target_bits = 0; 39 40 if (host_bits & float_flag_invalid) { 41 target_bits |= 1; 42 } 43 if (host_bits & float_flag_divbyzero) { 44 target_bits |= 2; 45 } 46 if (host_bits & float_flag_overflow) { 47 target_bits |= 4; 48 } 49 if (host_bits & (float_flag_underflow | float_flag_output_denormal)) { 50 target_bits |= 8; 51 } 52 if (host_bits & float_flag_inexact) { 53 target_bits |= 0x10; 54 } 55 if (host_bits & float_flag_input_denormal) { 56 target_bits |= 0x80; 57 } 58 return target_bits; 59 } 60 61 /* Convert vfp exception flags to target form. */ 62 static inline int vfp_exceptbits_to_host(int target_bits) 63 { 64 int host_bits = 0; 65 66 if (target_bits & 1) { 67 host_bits |= float_flag_invalid; 68 } 69 if (target_bits & 2) { 70 host_bits |= float_flag_divbyzero; 71 } 72 if (target_bits & 4) { 73 host_bits |= float_flag_overflow; 74 } 75 if (target_bits & 8) { 76 host_bits |= float_flag_underflow; 77 } 78 if (target_bits & 0x10) { 79 host_bits |= float_flag_inexact; 80 } 81 if (target_bits & 0x80) { 82 host_bits |= float_flag_input_denormal; 83 } 84 return host_bits; 85 } 86 87 static uint32_t vfp_get_fpscr_from_host(CPUARMState *env) 88 { 89 uint32_t i; 90 91 i = get_float_exception_flags(&env->vfp.fp_status); 92 i |= get_float_exception_flags(&env->vfp.standard_fp_status); 93 /* FZ16 does not generate an input denormal exception. */ 94 i |= (get_float_exception_flags(&env->vfp.fp_status_f16) 95 & ~float_flag_input_denormal); 96 return vfp_exceptbits_from_host(i); 97 } 98 99 static void vfp_set_fpscr_to_host(CPUARMState *env, uint32_t val) 100 { 101 int i; 102 uint32_t changed = env->vfp.xregs[ARM_VFP_FPSCR]; 103 104 changed ^= val; 105 if (changed & (3 << 22)) { 106 i = (val >> 22) & 3; 107 switch (i) { 108 case FPROUNDING_TIEEVEN: 109 i = float_round_nearest_even; 110 break; 111 case FPROUNDING_POSINF: 112 i = float_round_up; 113 break; 114 case FPROUNDING_NEGINF: 115 i = float_round_down; 116 break; 117 case FPROUNDING_ZERO: 118 i = float_round_to_zero; 119 break; 120 } 121 set_float_rounding_mode(i, &env->vfp.fp_status); 122 set_float_rounding_mode(i, &env->vfp.fp_status_f16); 123 } 124 if (changed & FPCR_FZ16) { 125 bool ftz_enabled = val & FPCR_FZ16; 126 set_flush_to_zero(ftz_enabled, &env->vfp.fp_status_f16); 127 set_flush_inputs_to_zero(ftz_enabled, &env->vfp.fp_status_f16); 128 } 129 if (changed & FPCR_FZ) { 130 bool ftz_enabled = val & FPCR_FZ; 131 set_flush_to_zero(ftz_enabled, &env->vfp.fp_status); 132 set_flush_inputs_to_zero(ftz_enabled, &env->vfp.fp_status); 133 } 134 if (changed & FPCR_DN) { 135 bool dnan_enabled = val & FPCR_DN; 136 set_default_nan_mode(dnan_enabled, &env->vfp.fp_status); 137 set_default_nan_mode(dnan_enabled, &env->vfp.fp_status_f16); 138 } 139 140 /* 141 * The exception flags are ORed together when we read fpscr so we 142 * only need to preserve the current state in one of our 143 * float_status values. 144 */ 145 i = vfp_exceptbits_to_host(val); 146 set_float_exception_flags(i, &env->vfp.fp_status); 147 set_float_exception_flags(0, &env->vfp.fp_status_f16); 148 set_float_exception_flags(0, &env->vfp.standard_fp_status); 149 } 150 151 #else 152 153 static uint32_t vfp_get_fpscr_from_host(CPUARMState *env) 154 { 155 return 0; 156 } 157 158 static void vfp_set_fpscr_to_host(CPUARMState *env, uint32_t val) 159 { 160 } 161 162 #endif 163 164 uint32_t HELPER(vfp_get_fpscr)(CPUARMState *env) 165 { 166 uint32_t i, fpscr; 167 168 fpscr = env->vfp.xregs[ARM_VFP_FPSCR] 169 | (env->vfp.vec_len << 16) 170 | (env->vfp.vec_stride << 20); 171 172 fpscr |= vfp_get_fpscr_from_host(env); 173 174 i = env->vfp.qc[0] | env->vfp.qc[1] | env->vfp.qc[2] | env->vfp.qc[3]; 175 fpscr |= i ? FPCR_QC : 0; 176 177 return fpscr; 178 } 179 180 uint32_t vfp_get_fpscr(CPUARMState *env) 181 { 182 return HELPER(vfp_get_fpscr)(env); 183 } 184 185 void HELPER(vfp_set_fpscr)(CPUARMState *env, uint32_t val) 186 { 187 /* When ARMv8.2-FP16 is not supported, FZ16 is RES0. */ 188 if (!cpu_isar_feature(aa64_fp16, env_archcpu(env))) { 189 val &= ~FPCR_FZ16; 190 } 191 192 if (arm_feature(env, ARM_FEATURE_M)) { 193 /* 194 * M profile FPSCR is RES0 for the QC, STRIDE, FZ16, LEN bits 195 * and also for the trapped-exception-handling bits IxE. 196 */ 197 val &= 0xf7c0009f; 198 } 199 200 vfp_set_fpscr_to_host(env, val); 201 202 /* 203 * We don't implement trapped exception handling, so the 204 * trap enable bits, IDE|IXE|UFE|OFE|DZE|IOE are all RAZ/WI (not RES0!) 205 * 206 * If we exclude the exception flags, IOC|DZC|OFC|UFC|IXC|IDC 207 * (which are stored in fp_status), and the other RES0 bits 208 * in between, then we clear all of the low 16 bits. 209 */ 210 env->vfp.xregs[ARM_VFP_FPSCR] = val & 0xf7c80000; 211 env->vfp.vec_len = (val >> 16) & 7; 212 env->vfp.vec_stride = (val >> 20) & 3; 213 214 /* 215 * The bit we set within fpscr_q is arbitrary; the register as a 216 * whole being zero/non-zero is what counts. 217 */ 218 env->vfp.qc[0] = val & FPCR_QC; 219 env->vfp.qc[1] = 0; 220 env->vfp.qc[2] = 0; 221 env->vfp.qc[3] = 0; 222 } 223 224 void vfp_set_fpscr(CPUARMState *env, uint32_t val) 225 { 226 HELPER(vfp_set_fpscr)(env, val); 227 } 228 229 #ifdef CONFIG_TCG 230 231 #define VFP_HELPER(name, p) HELPER(glue(glue(vfp_,name),p)) 232 233 #define VFP_BINOP(name) \ 234 float32 VFP_HELPER(name, s)(float32 a, float32 b, void *fpstp) \ 235 { \ 236 float_status *fpst = fpstp; \ 237 return float32_ ## name(a, b, fpst); \ 238 } \ 239 float64 VFP_HELPER(name, d)(float64 a, float64 b, void *fpstp) \ 240 { \ 241 float_status *fpst = fpstp; \ 242 return float64_ ## name(a, b, fpst); \ 243 } 244 VFP_BINOP(add) 245 VFP_BINOP(sub) 246 VFP_BINOP(mul) 247 VFP_BINOP(div) 248 VFP_BINOP(min) 249 VFP_BINOP(max) 250 VFP_BINOP(minnum) 251 VFP_BINOP(maxnum) 252 #undef VFP_BINOP 253 254 float32 VFP_HELPER(neg, s)(float32 a) 255 { 256 return float32_chs(a); 257 } 258 259 float64 VFP_HELPER(neg, d)(float64 a) 260 { 261 return float64_chs(a); 262 } 263 264 float32 VFP_HELPER(abs, s)(float32 a) 265 { 266 return float32_abs(a); 267 } 268 269 float64 VFP_HELPER(abs, d)(float64 a) 270 { 271 return float64_abs(a); 272 } 273 274 float32 VFP_HELPER(sqrt, s)(float32 a, CPUARMState *env) 275 { 276 return float32_sqrt(a, &env->vfp.fp_status); 277 } 278 279 float64 VFP_HELPER(sqrt, d)(float64 a, CPUARMState *env) 280 { 281 return float64_sqrt(a, &env->vfp.fp_status); 282 } 283 284 static void softfloat_to_vfp_compare(CPUARMState *env, int cmp) 285 { 286 uint32_t flags; 287 switch (cmp) { 288 case float_relation_equal: 289 flags = 0x6; 290 break; 291 case float_relation_less: 292 flags = 0x8; 293 break; 294 case float_relation_greater: 295 flags = 0x2; 296 break; 297 case float_relation_unordered: 298 flags = 0x3; 299 break; 300 default: 301 g_assert_not_reached(); 302 } 303 env->vfp.xregs[ARM_VFP_FPSCR] = 304 deposit32(env->vfp.xregs[ARM_VFP_FPSCR], 28, 4, flags); 305 } 306 307 /* XXX: check quiet/signaling case */ 308 #define DO_VFP_cmp(p, type) \ 309 void VFP_HELPER(cmp, p)(type a, type b, CPUARMState *env) \ 310 { \ 311 softfloat_to_vfp_compare(env, \ 312 type ## _compare_quiet(a, b, &env->vfp.fp_status)); \ 313 } \ 314 void VFP_HELPER(cmpe, p)(type a, type b, CPUARMState *env) \ 315 { \ 316 softfloat_to_vfp_compare(env, \ 317 type ## _compare(a, b, &env->vfp.fp_status)); \ 318 } 319 DO_VFP_cmp(s, float32) 320 DO_VFP_cmp(d, float64) 321 #undef DO_VFP_cmp 322 323 /* Integer to float and float to integer conversions */ 324 325 #define CONV_ITOF(name, ftype, fsz, sign) \ 326 ftype HELPER(name)(uint32_t x, void *fpstp) \ 327 { \ 328 float_status *fpst = fpstp; \ 329 return sign##int32_to_##float##fsz((sign##int32_t)x, fpst); \ 330 } 331 332 #define CONV_FTOI(name, ftype, fsz, sign, round) \ 333 sign##int32_t HELPER(name)(ftype x, void *fpstp) \ 334 { \ 335 float_status *fpst = fpstp; \ 336 if (float##fsz##_is_any_nan(x)) { \ 337 float_raise(float_flag_invalid, fpst); \ 338 return 0; \ 339 } \ 340 return float##fsz##_to_##sign##int32##round(x, fpst); \ 341 } 342 343 #define FLOAT_CONVS(name, p, ftype, fsz, sign) \ 344 CONV_ITOF(vfp_##name##to##p, ftype, fsz, sign) \ 345 CONV_FTOI(vfp_to##name##p, ftype, fsz, sign, ) \ 346 CONV_FTOI(vfp_to##name##z##p, ftype, fsz, sign, _round_to_zero) 347 348 FLOAT_CONVS(si, h, uint32_t, 16, ) 349 FLOAT_CONVS(si, s, float32, 32, ) 350 FLOAT_CONVS(si, d, float64, 64, ) 351 FLOAT_CONVS(ui, h, uint32_t, 16, u) 352 FLOAT_CONVS(ui, s, float32, 32, u) 353 FLOAT_CONVS(ui, d, float64, 64, u) 354 355 #undef CONV_ITOF 356 #undef CONV_FTOI 357 #undef FLOAT_CONVS 358 359 /* floating point conversion */ 360 float64 VFP_HELPER(fcvtd, s)(float32 x, CPUARMState *env) 361 { 362 return float32_to_float64(x, &env->vfp.fp_status); 363 } 364 365 float32 VFP_HELPER(fcvts, d)(float64 x, CPUARMState *env) 366 { 367 return float64_to_float32(x, &env->vfp.fp_status); 368 } 369 370 /* VFP3 fixed point conversion. */ 371 #define VFP_CONV_FIX_FLOAT(name, p, fsz, isz, itype) \ 372 float##fsz HELPER(vfp_##name##to##p)(uint##isz##_t x, uint32_t shift, \ 373 void *fpstp) \ 374 { return itype##_to_##float##fsz##_scalbn(x, -shift, fpstp); } 375 376 #define VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, isz, itype, ROUND, suff) \ 377 uint##isz##_t HELPER(vfp_to##name##p##suff)(float##fsz x, uint32_t shift, \ 378 void *fpst) \ 379 { \ 380 if (unlikely(float##fsz##_is_any_nan(x))) { \ 381 float_raise(float_flag_invalid, fpst); \ 382 return 0; \ 383 } \ 384 return float##fsz##_to_##itype##_scalbn(x, ROUND, shift, fpst); \ 385 } 386 387 #define VFP_CONV_FIX(name, p, fsz, isz, itype) \ 388 VFP_CONV_FIX_FLOAT(name, p, fsz, isz, itype) \ 389 VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, isz, itype, \ 390 float_round_to_zero, _round_to_zero) \ 391 VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, isz, itype, \ 392 get_float_rounding_mode(fpst), ) 393 394 #define VFP_CONV_FIX_A64(name, p, fsz, isz, itype) \ 395 VFP_CONV_FIX_FLOAT(name, p, fsz, isz, itype) \ 396 VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, isz, itype, \ 397 get_float_rounding_mode(fpst), ) 398 399 VFP_CONV_FIX(sh, d, 64, 64, int16) 400 VFP_CONV_FIX(sl, d, 64, 64, int32) 401 VFP_CONV_FIX_A64(sq, d, 64, 64, int64) 402 VFP_CONV_FIX(uh, d, 64, 64, uint16) 403 VFP_CONV_FIX(ul, d, 64, 64, uint32) 404 VFP_CONV_FIX_A64(uq, d, 64, 64, uint64) 405 VFP_CONV_FIX(sh, s, 32, 32, int16) 406 VFP_CONV_FIX(sl, s, 32, 32, int32) 407 VFP_CONV_FIX_A64(sq, s, 32, 64, int64) 408 VFP_CONV_FIX(uh, s, 32, 32, uint16) 409 VFP_CONV_FIX(ul, s, 32, 32, uint32) 410 VFP_CONV_FIX_A64(uq, s, 32, 64, uint64) 411 412 #undef VFP_CONV_FIX 413 #undef VFP_CONV_FIX_FLOAT 414 #undef VFP_CONV_FLOAT_FIX_ROUND 415 #undef VFP_CONV_FIX_A64 416 417 uint32_t HELPER(vfp_sltoh)(uint32_t x, uint32_t shift, void *fpst) 418 { 419 return int32_to_float16_scalbn(x, -shift, fpst); 420 } 421 422 uint32_t HELPER(vfp_ultoh)(uint32_t x, uint32_t shift, void *fpst) 423 { 424 return uint32_to_float16_scalbn(x, -shift, fpst); 425 } 426 427 uint32_t HELPER(vfp_sqtoh)(uint64_t x, uint32_t shift, void *fpst) 428 { 429 return int64_to_float16_scalbn(x, -shift, fpst); 430 } 431 432 uint32_t HELPER(vfp_uqtoh)(uint64_t x, uint32_t shift, void *fpst) 433 { 434 return uint64_to_float16_scalbn(x, -shift, fpst); 435 } 436 437 uint32_t HELPER(vfp_toshh)(uint32_t x, uint32_t shift, void *fpst) 438 { 439 if (unlikely(float16_is_any_nan(x))) { 440 float_raise(float_flag_invalid, fpst); 441 return 0; 442 } 443 return float16_to_int16_scalbn(x, get_float_rounding_mode(fpst), 444 shift, fpst); 445 } 446 447 uint32_t HELPER(vfp_touhh)(uint32_t x, uint32_t shift, void *fpst) 448 { 449 if (unlikely(float16_is_any_nan(x))) { 450 float_raise(float_flag_invalid, fpst); 451 return 0; 452 } 453 return float16_to_uint16_scalbn(x, get_float_rounding_mode(fpst), 454 shift, fpst); 455 } 456 457 uint32_t HELPER(vfp_toslh)(uint32_t x, uint32_t shift, void *fpst) 458 { 459 if (unlikely(float16_is_any_nan(x))) { 460 float_raise(float_flag_invalid, fpst); 461 return 0; 462 } 463 return float16_to_int32_scalbn(x, get_float_rounding_mode(fpst), 464 shift, fpst); 465 } 466 467 uint32_t HELPER(vfp_toulh)(uint32_t x, uint32_t shift, void *fpst) 468 { 469 if (unlikely(float16_is_any_nan(x))) { 470 float_raise(float_flag_invalid, fpst); 471 return 0; 472 } 473 return float16_to_uint32_scalbn(x, get_float_rounding_mode(fpst), 474 shift, fpst); 475 } 476 477 uint64_t HELPER(vfp_tosqh)(uint32_t x, uint32_t shift, void *fpst) 478 { 479 if (unlikely(float16_is_any_nan(x))) { 480 float_raise(float_flag_invalid, fpst); 481 return 0; 482 } 483 return float16_to_int64_scalbn(x, get_float_rounding_mode(fpst), 484 shift, fpst); 485 } 486 487 uint64_t HELPER(vfp_touqh)(uint32_t x, uint32_t shift, void *fpst) 488 { 489 if (unlikely(float16_is_any_nan(x))) { 490 float_raise(float_flag_invalid, fpst); 491 return 0; 492 } 493 return float16_to_uint64_scalbn(x, get_float_rounding_mode(fpst), 494 shift, fpst); 495 } 496 497 /* Set the current fp rounding mode and return the old one. 498 * The argument is a softfloat float_round_ value. 499 */ 500 uint32_t HELPER(set_rmode)(uint32_t rmode, void *fpstp) 501 { 502 float_status *fp_status = fpstp; 503 504 uint32_t prev_rmode = get_float_rounding_mode(fp_status); 505 set_float_rounding_mode(rmode, fp_status); 506 507 return prev_rmode; 508 } 509 510 /* Set the current fp rounding mode in the standard fp status and return 511 * the old one. This is for NEON instructions that need to change the 512 * rounding mode but wish to use the standard FPSCR values for everything 513 * else. Always set the rounding mode back to the correct value after 514 * modifying it. 515 * The argument is a softfloat float_round_ value. 516 */ 517 uint32_t HELPER(set_neon_rmode)(uint32_t rmode, CPUARMState *env) 518 { 519 float_status *fp_status = &env->vfp.standard_fp_status; 520 521 uint32_t prev_rmode = get_float_rounding_mode(fp_status); 522 set_float_rounding_mode(rmode, fp_status); 523 524 return prev_rmode; 525 } 526 527 /* Half precision conversions. */ 528 float32 HELPER(vfp_fcvt_f16_to_f32)(uint32_t a, void *fpstp, uint32_t ahp_mode) 529 { 530 /* Squash FZ16 to 0 for the duration of conversion. In this case, 531 * it would affect flushing input denormals. 532 */ 533 float_status *fpst = fpstp; 534 flag save = get_flush_inputs_to_zero(fpst); 535 set_flush_inputs_to_zero(false, fpst); 536 float32 r = float16_to_float32(a, !ahp_mode, fpst); 537 set_flush_inputs_to_zero(save, fpst); 538 return r; 539 } 540 541 uint32_t HELPER(vfp_fcvt_f32_to_f16)(float32 a, void *fpstp, uint32_t ahp_mode) 542 { 543 /* Squash FZ16 to 0 for the duration of conversion. In this case, 544 * it would affect flushing output denormals. 545 */ 546 float_status *fpst = fpstp; 547 flag save = get_flush_to_zero(fpst); 548 set_flush_to_zero(false, fpst); 549 float16 r = float32_to_float16(a, !ahp_mode, fpst); 550 set_flush_to_zero(save, fpst); 551 return r; 552 } 553 554 float64 HELPER(vfp_fcvt_f16_to_f64)(uint32_t a, void *fpstp, uint32_t ahp_mode) 555 { 556 /* Squash FZ16 to 0 for the duration of conversion. In this case, 557 * it would affect flushing input denormals. 558 */ 559 float_status *fpst = fpstp; 560 flag save = get_flush_inputs_to_zero(fpst); 561 set_flush_inputs_to_zero(false, fpst); 562 float64 r = float16_to_float64(a, !ahp_mode, fpst); 563 set_flush_inputs_to_zero(save, fpst); 564 return r; 565 } 566 567 uint32_t HELPER(vfp_fcvt_f64_to_f16)(float64 a, void *fpstp, uint32_t ahp_mode) 568 { 569 /* Squash FZ16 to 0 for the duration of conversion. In this case, 570 * it would affect flushing output denormals. 571 */ 572 float_status *fpst = fpstp; 573 flag save = get_flush_to_zero(fpst); 574 set_flush_to_zero(false, fpst); 575 float16 r = float64_to_float16(a, !ahp_mode, fpst); 576 set_flush_to_zero(save, fpst); 577 return r; 578 } 579 580 #define float32_two make_float32(0x40000000) 581 #define float32_three make_float32(0x40400000) 582 #define float32_one_point_five make_float32(0x3fc00000) 583 584 float32 HELPER(recps_f32)(float32 a, float32 b, CPUARMState *env) 585 { 586 float_status *s = &env->vfp.standard_fp_status; 587 if ((float32_is_infinity(a) && float32_is_zero_or_denormal(b)) || 588 (float32_is_infinity(b) && float32_is_zero_or_denormal(a))) { 589 if (!(float32_is_zero(a) || float32_is_zero(b))) { 590 float_raise(float_flag_input_denormal, s); 591 } 592 return float32_two; 593 } 594 return float32_sub(float32_two, float32_mul(a, b, s), s); 595 } 596 597 float32 HELPER(rsqrts_f32)(float32 a, float32 b, CPUARMState *env) 598 { 599 float_status *s = &env->vfp.standard_fp_status; 600 float32 product; 601 if ((float32_is_infinity(a) && float32_is_zero_or_denormal(b)) || 602 (float32_is_infinity(b) && float32_is_zero_or_denormal(a))) { 603 if (!(float32_is_zero(a) || float32_is_zero(b))) { 604 float_raise(float_flag_input_denormal, s); 605 } 606 return float32_one_point_five; 607 } 608 product = float32_mul(a, b, s); 609 return float32_div(float32_sub(float32_three, product, s), float32_two, s); 610 } 611 612 /* NEON helpers. */ 613 614 /* Constants 256 and 512 are used in some helpers; we avoid relying on 615 * int->float conversions at run-time. */ 616 #define float64_256 make_float64(0x4070000000000000LL) 617 #define float64_512 make_float64(0x4080000000000000LL) 618 #define float16_maxnorm make_float16(0x7bff) 619 #define float32_maxnorm make_float32(0x7f7fffff) 620 #define float64_maxnorm make_float64(0x7fefffffffffffffLL) 621 622 /* Reciprocal functions 623 * 624 * The algorithm that must be used to calculate the estimate 625 * is specified by the ARM ARM, see FPRecipEstimate()/RecipEstimate 626 */ 627 628 /* See RecipEstimate() 629 * 630 * input is a 9 bit fixed point number 631 * input range 256 .. 511 for a number from 0.5 <= x < 1.0. 632 * result range 256 .. 511 for a number from 1.0 to 511/256. 633 */ 634 635 static int recip_estimate(int input) 636 { 637 int a, b, r; 638 assert(256 <= input && input < 512); 639 a = (input * 2) + 1; 640 b = (1 << 19) / a; 641 r = (b + 1) >> 1; 642 assert(256 <= r && r < 512); 643 return r; 644 } 645 646 /* 647 * Common wrapper to call recip_estimate 648 * 649 * The parameters are exponent and 64 bit fraction (without implicit 650 * bit) where the binary point is nominally at bit 52. Returns a 651 * float64 which can then be rounded to the appropriate size by the 652 * callee. 653 */ 654 655 static uint64_t call_recip_estimate(int *exp, int exp_off, uint64_t frac) 656 { 657 uint32_t scaled, estimate; 658 uint64_t result_frac; 659 int result_exp; 660 661 /* Handle sub-normals */ 662 if (*exp == 0) { 663 if (extract64(frac, 51, 1) == 0) { 664 *exp = -1; 665 frac <<= 2; 666 } else { 667 frac <<= 1; 668 } 669 } 670 671 /* scaled = UInt('1':fraction<51:44>) */ 672 scaled = deposit32(1 << 8, 0, 8, extract64(frac, 44, 8)); 673 estimate = recip_estimate(scaled); 674 675 result_exp = exp_off - *exp; 676 result_frac = deposit64(0, 44, 8, estimate); 677 if (result_exp == 0) { 678 result_frac = deposit64(result_frac >> 1, 51, 1, 1); 679 } else if (result_exp == -1) { 680 result_frac = deposit64(result_frac >> 2, 50, 2, 1); 681 result_exp = 0; 682 } 683 684 *exp = result_exp; 685 686 return result_frac; 687 } 688 689 static bool round_to_inf(float_status *fpst, bool sign_bit) 690 { 691 switch (fpst->float_rounding_mode) { 692 case float_round_nearest_even: /* Round to Nearest */ 693 return true; 694 case float_round_up: /* Round to +Inf */ 695 return !sign_bit; 696 case float_round_down: /* Round to -Inf */ 697 return sign_bit; 698 case float_round_to_zero: /* Round to Zero */ 699 return false; 700 } 701 702 g_assert_not_reached(); 703 } 704 705 uint32_t HELPER(recpe_f16)(uint32_t input, void *fpstp) 706 { 707 float_status *fpst = fpstp; 708 float16 f16 = float16_squash_input_denormal(input, fpst); 709 uint32_t f16_val = float16_val(f16); 710 uint32_t f16_sign = float16_is_neg(f16); 711 int f16_exp = extract32(f16_val, 10, 5); 712 uint32_t f16_frac = extract32(f16_val, 0, 10); 713 uint64_t f64_frac; 714 715 if (float16_is_any_nan(f16)) { 716 float16 nan = f16; 717 if (float16_is_signaling_nan(f16, fpst)) { 718 float_raise(float_flag_invalid, fpst); 719 nan = float16_silence_nan(f16, fpst); 720 } 721 if (fpst->default_nan_mode) { 722 nan = float16_default_nan(fpst); 723 } 724 return nan; 725 } else if (float16_is_infinity(f16)) { 726 return float16_set_sign(float16_zero, float16_is_neg(f16)); 727 } else if (float16_is_zero(f16)) { 728 float_raise(float_flag_divbyzero, fpst); 729 return float16_set_sign(float16_infinity, float16_is_neg(f16)); 730 } else if (float16_abs(f16) < (1 << 8)) { 731 /* Abs(value) < 2.0^-16 */ 732 float_raise(float_flag_overflow | float_flag_inexact, fpst); 733 if (round_to_inf(fpst, f16_sign)) { 734 return float16_set_sign(float16_infinity, f16_sign); 735 } else { 736 return float16_set_sign(float16_maxnorm, f16_sign); 737 } 738 } else if (f16_exp >= 29 && fpst->flush_to_zero) { 739 float_raise(float_flag_underflow, fpst); 740 return float16_set_sign(float16_zero, float16_is_neg(f16)); 741 } 742 743 f64_frac = call_recip_estimate(&f16_exp, 29, 744 ((uint64_t) f16_frac) << (52 - 10)); 745 746 /* result = sign : result_exp<4:0> : fraction<51:42> */ 747 f16_val = deposit32(0, 15, 1, f16_sign); 748 f16_val = deposit32(f16_val, 10, 5, f16_exp); 749 f16_val = deposit32(f16_val, 0, 10, extract64(f64_frac, 52 - 10, 10)); 750 return make_float16(f16_val); 751 } 752 753 float32 HELPER(recpe_f32)(float32 input, void *fpstp) 754 { 755 float_status *fpst = fpstp; 756 float32 f32 = float32_squash_input_denormal(input, fpst); 757 uint32_t f32_val = float32_val(f32); 758 bool f32_sign = float32_is_neg(f32); 759 int f32_exp = extract32(f32_val, 23, 8); 760 uint32_t f32_frac = extract32(f32_val, 0, 23); 761 uint64_t f64_frac; 762 763 if (float32_is_any_nan(f32)) { 764 float32 nan = f32; 765 if (float32_is_signaling_nan(f32, fpst)) { 766 float_raise(float_flag_invalid, fpst); 767 nan = float32_silence_nan(f32, fpst); 768 } 769 if (fpst->default_nan_mode) { 770 nan = float32_default_nan(fpst); 771 } 772 return nan; 773 } else if (float32_is_infinity(f32)) { 774 return float32_set_sign(float32_zero, float32_is_neg(f32)); 775 } else if (float32_is_zero(f32)) { 776 float_raise(float_flag_divbyzero, fpst); 777 return float32_set_sign(float32_infinity, float32_is_neg(f32)); 778 } else if (float32_abs(f32) < (1ULL << 21)) { 779 /* Abs(value) < 2.0^-128 */ 780 float_raise(float_flag_overflow | float_flag_inexact, fpst); 781 if (round_to_inf(fpst, f32_sign)) { 782 return float32_set_sign(float32_infinity, f32_sign); 783 } else { 784 return float32_set_sign(float32_maxnorm, f32_sign); 785 } 786 } else if (f32_exp >= 253 && fpst->flush_to_zero) { 787 float_raise(float_flag_underflow, fpst); 788 return float32_set_sign(float32_zero, float32_is_neg(f32)); 789 } 790 791 f64_frac = call_recip_estimate(&f32_exp, 253, 792 ((uint64_t) f32_frac) << (52 - 23)); 793 794 /* result = sign : result_exp<7:0> : fraction<51:29> */ 795 f32_val = deposit32(0, 31, 1, f32_sign); 796 f32_val = deposit32(f32_val, 23, 8, f32_exp); 797 f32_val = deposit32(f32_val, 0, 23, extract64(f64_frac, 52 - 23, 23)); 798 return make_float32(f32_val); 799 } 800 801 float64 HELPER(recpe_f64)(float64 input, void *fpstp) 802 { 803 float_status *fpst = fpstp; 804 float64 f64 = float64_squash_input_denormal(input, fpst); 805 uint64_t f64_val = float64_val(f64); 806 bool f64_sign = float64_is_neg(f64); 807 int f64_exp = extract64(f64_val, 52, 11); 808 uint64_t f64_frac = extract64(f64_val, 0, 52); 809 810 /* Deal with any special cases */ 811 if (float64_is_any_nan(f64)) { 812 float64 nan = f64; 813 if (float64_is_signaling_nan(f64, fpst)) { 814 float_raise(float_flag_invalid, fpst); 815 nan = float64_silence_nan(f64, fpst); 816 } 817 if (fpst->default_nan_mode) { 818 nan = float64_default_nan(fpst); 819 } 820 return nan; 821 } else if (float64_is_infinity(f64)) { 822 return float64_set_sign(float64_zero, float64_is_neg(f64)); 823 } else if (float64_is_zero(f64)) { 824 float_raise(float_flag_divbyzero, fpst); 825 return float64_set_sign(float64_infinity, float64_is_neg(f64)); 826 } else if ((f64_val & ~(1ULL << 63)) < (1ULL << 50)) { 827 /* Abs(value) < 2.0^-1024 */ 828 float_raise(float_flag_overflow | float_flag_inexact, fpst); 829 if (round_to_inf(fpst, f64_sign)) { 830 return float64_set_sign(float64_infinity, f64_sign); 831 } else { 832 return float64_set_sign(float64_maxnorm, f64_sign); 833 } 834 } else if (f64_exp >= 2045 && fpst->flush_to_zero) { 835 float_raise(float_flag_underflow, fpst); 836 return float64_set_sign(float64_zero, float64_is_neg(f64)); 837 } 838 839 f64_frac = call_recip_estimate(&f64_exp, 2045, f64_frac); 840 841 /* result = sign : result_exp<10:0> : fraction<51:0>; */ 842 f64_val = deposit64(0, 63, 1, f64_sign); 843 f64_val = deposit64(f64_val, 52, 11, f64_exp); 844 f64_val = deposit64(f64_val, 0, 52, f64_frac); 845 return make_float64(f64_val); 846 } 847 848 /* The algorithm that must be used to calculate the estimate 849 * is specified by the ARM ARM. 850 */ 851 852 static int do_recip_sqrt_estimate(int a) 853 { 854 int b, estimate; 855 856 assert(128 <= a && a < 512); 857 if (a < 256) { 858 a = a * 2 + 1; 859 } else { 860 a = (a >> 1) << 1; 861 a = (a + 1) * 2; 862 } 863 b = 512; 864 while (a * (b + 1) * (b + 1) < (1 << 28)) { 865 b += 1; 866 } 867 estimate = (b + 1) / 2; 868 assert(256 <= estimate && estimate < 512); 869 870 return estimate; 871 } 872 873 874 static uint64_t recip_sqrt_estimate(int *exp , int exp_off, uint64_t frac) 875 { 876 int estimate; 877 uint32_t scaled; 878 879 if (*exp == 0) { 880 while (extract64(frac, 51, 1) == 0) { 881 frac = frac << 1; 882 *exp -= 1; 883 } 884 frac = extract64(frac, 0, 51) << 1; 885 } 886 887 if (*exp & 1) { 888 /* scaled = UInt('01':fraction<51:45>) */ 889 scaled = deposit32(1 << 7, 0, 7, extract64(frac, 45, 7)); 890 } else { 891 /* scaled = UInt('1':fraction<51:44>) */ 892 scaled = deposit32(1 << 8, 0, 8, extract64(frac, 44, 8)); 893 } 894 estimate = do_recip_sqrt_estimate(scaled); 895 896 *exp = (exp_off - *exp) / 2; 897 return extract64(estimate, 0, 8) << 44; 898 } 899 900 uint32_t HELPER(rsqrte_f16)(uint32_t input, void *fpstp) 901 { 902 float_status *s = fpstp; 903 float16 f16 = float16_squash_input_denormal(input, s); 904 uint16_t val = float16_val(f16); 905 bool f16_sign = float16_is_neg(f16); 906 int f16_exp = extract32(val, 10, 5); 907 uint16_t f16_frac = extract32(val, 0, 10); 908 uint64_t f64_frac; 909 910 if (float16_is_any_nan(f16)) { 911 float16 nan = f16; 912 if (float16_is_signaling_nan(f16, s)) { 913 float_raise(float_flag_invalid, s); 914 nan = float16_silence_nan(f16, s); 915 } 916 if (s->default_nan_mode) { 917 nan = float16_default_nan(s); 918 } 919 return nan; 920 } else if (float16_is_zero(f16)) { 921 float_raise(float_flag_divbyzero, s); 922 return float16_set_sign(float16_infinity, f16_sign); 923 } else if (f16_sign) { 924 float_raise(float_flag_invalid, s); 925 return float16_default_nan(s); 926 } else if (float16_is_infinity(f16)) { 927 return float16_zero; 928 } 929 930 /* Scale and normalize to a double-precision value between 0.25 and 1.0, 931 * preserving the parity of the exponent. */ 932 933 f64_frac = ((uint64_t) f16_frac) << (52 - 10); 934 935 f64_frac = recip_sqrt_estimate(&f16_exp, 44, f64_frac); 936 937 /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(2) */ 938 val = deposit32(0, 15, 1, f16_sign); 939 val = deposit32(val, 10, 5, f16_exp); 940 val = deposit32(val, 2, 8, extract64(f64_frac, 52 - 8, 8)); 941 return make_float16(val); 942 } 943 944 float32 HELPER(rsqrte_f32)(float32 input, void *fpstp) 945 { 946 float_status *s = fpstp; 947 float32 f32 = float32_squash_input_denormal(input, s); 948 uint32_t val = float32_val(f32); 949 uint32_t f32_sign = float32_is_neg(f32); 950 int f32_exp = extract32(val, 23, 8); 951 uint32_t f32_frac = extract32(val, 0, 23); 952 uint64_t f64_frac; 953 954 if (float32_is_any_nan(f32)) { 955 float32 nan = f32; 956 if (float32_is_signaling_nan(f32, s)) { 957 float_raise(float_flag_invalid, s); 958 nan = float32_silence_nan(f32, s); 959 } 960 if (s->default_nan_mode) { 961 nan = float32_default_nan(s); 962 } 963 return nan; 964 } else if (float32_is_zero(f32)) { 965 float_raise(float_flag_divbyzero, s); 966 return float32_set_sign(float32_infinity, float32_is_neg(f32)); 967 } else if (float32_is_neg(f32)) { 968 float_raise(float_flag_invalid, s); 969 return float32_default_nan(s); 970 } else if (float32_is_infinity(f32)) { 971 return float32_zero; 972 } 973 974 /* Scale and normalize to a double-precision value between 0.25 and 1.0, 975 * preserving the parity of the exponent. */ 976 977 f64_frac = ((uint64_t) f32_frac) << 29; 978 979 f64_frac = recip_sqrt_estimate(&f32_exp, 380, f64_frac); 980 981 /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(15) */ 982 val = deposit32(0, 31, 1, f32_sign); 983 val = deposit32(val, 23, 8, f32_exp); 984 val = deposit32(val, 15, 8, extract64(f64_frac, 52 - 8, 8)); 985 return make_float32(val); 986 } 987 988 float64 HELPER(rsqrte_f64)(float64 input, void *fpstp) 989 { 990 float_status *s = fpstp; 991 float64 f64 = float64_squash_input_denormal(input, s); 992 uint64_t val = float64_val(f64); 993 bool f64_sign = float64_is_neg(f64); 994 int f64_exp = extract64(val, 52, 11); 995 uint64_t f64_frac = extract64(val, 0, 52); 996 997 if (float64_is_any_nan(f64)) { 998 float64 nan = f64; 999 if (float64_is_signaling_nan(f64, s)) { 1000 float_raise(float_flag_invalid, s); 1001 nan = float64_silence_nan(f64, s); 1002 } 1003 if (s->default_nan_mode) { 1004 nan = float64_default_nan(s); 1005 } 1006 return nan; 1007 } else if (float64_is_zero(f64)) { 1008 float_raise(float_flag_divbyzero, s); 1009 return float64_set_sign(float64_infinity, float64_is_neg(f64)); 1010 } else if (float64_is_neg(f64)) { 1011 float_raise(float_flag_invalid, s); 1012 return float64_default_nan(s); 1013 } else if (float64_is_infinity(f64)) { 1014 return float64_zero; 1015 } 1016 1017 f64_frac = recip_sqrt_estimate(&f64_exp, 3068, f64_frac); 1018 1019 /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(44) */ 1020 val = deposit64(0, 61, 1, f64_sign); 1021 val = deposit64(val, 52, 11, f64_exp); 1022 val = deposit64(val, 44, 8, extract64(f64_frac, 52 - 8, 8)); 1023 return make_float64(val); 1024 } 1025 1026 uint32_t HELPER(recpe_u32)(uint32_t a, void *fpstp) 1027 { 1028 /* float_status *s = fpstp; */ 1029 int input, estimate; 1030 1031 if ((a & 0x80000000) == 0) { 1032 return 0xffffffff; 1033 } 1034 1035 input = extract32(a, 23, 9); 1036 estimate = recip_estimate(input); 1037 1038 return deposit32(0, (32 - 9), 9, estimate); 1039 } 1040 1041 uint32_t HELPER(rsqrte_u32)(uint32_t a, void *fpstp) 1042 { 1043 int estimate; 1044 1045 if ((a & 0xc0000000) == 0) { 1046 return 0xffffffff; 1047 } 1048 1049 estimate = do_recip_sqrt_estimate(extract32(a, 23, 9)); 1050 1051 return deposit32(0, 23, 9, estimate); 1052 } 1053 1054 /* VFPv4 fused multiply-accumulate */ 1055 float32 VFP_HELPER(muladd, s)(float32 a, float32 b, float32 c, void *fpstp) 1056 { 1057 float_status *fpst = fpstp; 1058 return float32_muladd(a, b, c, 0, fpst); 1059 } 1060 1061 float64 VFP_HELPER(muladd, d)(float64 a, float64 b, float64 c, void *fpstp) 1062 { 1063 float_status *fpst = fpstp; 1064 return float64_muladd(a, b, c, 0, fpst); 1065 } 1066 1067 /* ARMv8 round to integral */ 1068 float32 HELPER(rints_exact)(float32 x, void *fp_status) 1069 { 1070 return float32_round_to_int(x, fp_status); 1071 } 1072 1073 float64 HELPER(rintd_exact)(float64 x, void *fp_status) 1074 { 1075 return float64_round_to_int(x, fp_status); 1076 } 1077 1078 float32 HELPER(rints)(float32 x, void *fp_status) 1079 { 1080 int old_flags = get_float_exception_flags(fp_status), new_flags; 1081 float32 ret; 1082 1083 ret = float32_round_to_int(x, fp_status); 1084 1085 /* Suppress any inexact exceptions the conversion produced */ 1086 if (!(old_flags & float_flag_inexact)) { 1087 new_flags = get_float_exception_flags(fp_status); 1088 set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status); 1089 } 1090 1091 return ret; 1092 } 1093 1094 float64 HELPER(rintd)(float64 x, void *fp_status) 1095 { 1096 int old_flags = get_float_exception_flags(fp_status), new_flags; 1097 float64 ret; 1098 1099 ret = float64_round_to_int(x, fp_status); 1100 1101 new_flags = get_float_exception_flags(fp_status); 1102 1103 /* Suppress any inexact exceptions the conversion produced */ 1104 if (!(old_flags & float_flag_inexact)) { 1105 new_flags = get_float_exception_flags(fp_status); 1106 set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status); 1107 } 1108 1109 return ret; 1110 } 1111 1112 /* Convert ARM rounding mode to softfloat */ 1113 int arm_rmode_to_sf(int rmode) 1114 { 1115 switch (rmode) { 1116 case FPROUNDING_TIEAWAY: 1117 rmode = float_round_ties_away; 1118 break; 1119 case FPROUNDING_ODD: 1120 /* FIXME: add support for TIEAWAY and ODD */ 1121 qemu_log_mask(LOG_UNIMP, "arm: unimplemented rounding mode: %d\n", 1122 rmode); 1123 /* fall through for now */ 1124 case FPROUNDING_TIEEVEN: 1125 default: 1126 rmode = float_round_nearest_even; 1127 break; 1128 case FPROUNDING_POSINF: 1129 rmode = float_round_up; 1130 break; 1131 case FPROUNDING_NEGINF: 1132 rmode = float_round_down; 1133 break; 1134 case FPROUNDING_ZERO: 1135 rmode = float_round_to_zero; 1136 break; 1137 } 1138 return rmode; 1139 } 1140 1141 /* 1142 * Implement float64 to int32_t conversion without saturation; 1143 * the result is supplied modulo 2^32. 1144 */ 1145 uint64_t HELPER(fjcvtzs)(float64 value, void *vstatus) 1146 { 1147 float_status *status = vstatus; 1148 uint32_t exp, sign; 1149 uint64_t frac; 1150 uint32_t inexact = 1; /* !Z */ 1151 1152 sign = extract64(value, 63, 1); 1153 exp = extract64(value, 52, 11); 1154 frac = extract64(value, 0, 52); 1155 1156 if (exp == 0) { 1157 /* While not inexact for IEEE FP, -0.0 is inexact for JavaScript. */ 1158 inexact = sign; 1159 if (frac != 0) { 1160 if (status->flush_inputs_to_zero) { 1161 float_raise(float_flag_input_denormal, status); 1162 } else { 1163 float_raise(float_flag_inexact, status); 1164 inexact = 1; 1165 } 1166 } 1167 frac = 0; 1168 } else if (exp == 0x7ff) { 1169 /* This operation raises Invalid for both NaN and overflow (Inf). */ 1170 float_raise(float_flag_invalid, status); 1171 frac = 0; 1172 } else { 1173 int true_exp = exp - 1023; 1174 int shift = true_exp - 52; 1175 1176 /* Restore implicit bit. */ 1177 frac |= 1ull << 52; 1178 1179 /* Shift the fraction into place. */ 1180 if (shift >= 0) { 1181 /* The number is so large we must shift the fraction left. */ 1182 if (shift >= 64) { 1183 /* The fraction is shifted out entirely. */ 1184 frac = 0; 1185 } else { 1186 frac <<= shift; 1187 } 1188 } else if (shift > -64) { 1189 /* Normal case -- shift right and notice if bits shift out. */ 1190 inexact = (frac << (64 + shift)) != 0; 1191 frac >>= -shift; 1192 } else { 1193 /* The fraction is shifted out entirely. */ 1194 frac = 0; 1195 } 1196 1197 /* Notice overflow or inexact exceptions. */ 1198 if (true_exp > 31 || frac > (sign ? 0x80000000ull : 0x7fffffff)) { 1199 /* Overflow, for which this operation raises invalid. */ 1200 float_raise(float_flag_invalid, status); 1201 inexact = 1; 1202 } else if (inexact) { 1203 float_raise(float_flag_inexact, status); 1204 } 1205 1206 /* Honor the sign. */ 1207 if (sign) { 1208 frac = -frac; 1209 } 1210 } 1211 1212 /* Pack the result and the env->ZF representation of Z together. */ 1213 return deposit64(frac, 32, 32, inexact); 1214 } 1215 1216 uint32_t HELPER(vjcvt)(float64 value, CPUARMState *env) 1217 { 1218 uint64_t pair = HELPER(fjcvtzs)(value, &env->vfp.fp_status); 1219 uint32_t result = pair; 1220 uint32_t z = (pair >> 32) == 0; 1221 1222 /* Store Z, clear NCV, in FPSCR.NZCV. */ 1223 env->vfp.xregs[ARM_VFP_FPSCR] 1224 = (env->vfp.xregs[ARM_VFP_FPSCR] & ~CPSR_NZCV) | (z * CPSR_Z); 1225 1226 return result; 1227 } 1228 1229 /* Round a float32 to an integer that fits in int32_t or int64_t. */ 1230 static float32 frint_s(float32 f, float_status *fpst, int intsize) 1231 { 1232 int old_flags = get_float_exception_flags(fpst); 1233 uint32_t exp = extract32(f, 23, 8); 1234 1235 if (unlikely(exp == 0xff)) { 1236 /* NaN or Inf. */ 1237 goto overflow; 1238 } 1239 1240 /* Round and re-extract the exponent. */ 1241 f = float32_round_to_int(f, fpst); 1242 exp = extract32(f, 23, 8); 1243 1244 /* Validate the range of the result. */ 1245 if (exp < 126 + intsize) { 1246 /* abs(F) <= INT{N}_MAX */ 1247 return f; 1248 } 1249 if (exp == 126 + intsize) { 1250 uint32_t sign = extract32(f, 31, 1); 1251 uint32_t frac = extract32(f, 0, 23); 1252 if (sign && frac == 0) { 1253 /* F == INT{N}_MIN */ 1254 return f; 1255 } 1256 } 1257 1258 overflow: 1259 /* 1260 * Raise Invalid and return INT{N}_MIN as a float. Revert any 1261 * inexact exception float32_round_to_int may have raised. 1262 */ 1263 set_float_exception_flags(old_flags | float_flag_invalid, fpst); 1264 return (0x100u + 126u + intsize) << 23; 1265 } 1266 1267 float32 HELPER(frint32_s)(float32 f, void *fpst) 1268 { 1269 return frint_s(f, fpst, 32); 1270 } 1271 1272 float32 HELPER(frint64_s)(float32 f, void *fpst) 1273 { 1274 return frint_s(f, fpst, 64); 1275 } 1276 1277 /* Round a float64 to an integer that fits in int32_t or int64_t. */ 1278 static float64 frint_d(float64 f, float_status *fpst, int intsize) 1279 { 1280 int old_flags = get_float_exception_flags(fpst); 1281 uint32_t exp = extract64(f, 52, 11); 1282 1283 if (unlikely(exp == 0x7ff)) { 1284 /* NaN or Inf. */ 1285 goto overflow; 1286 } 1287 1288 /* Round and re-extract the exponent. */ 1289 f = float64_round_to_int(f, fpst); 1290 exp = extract64(f, 52, 11); 1291 1292 /* Validate the range of the result. */ 1293 if (exp < 1022 + intsize) { 1294 /* abs(F) <= INT{N}_MAX */ 1295 return f; 1296 } 1297 if (exp == 1022 + intsize) { 1298 uint64_t sign = extract64(f, 63, 1); 1299 uint64_t frac = extract64(f, 0, 52); 1300 if (sign && frac == 0) { 1301 /* F == INT{N}_MIN */ 1302 return f; 1303 } 1304 } 1305 1306 overflow: 1307 /* 1308 * Raise Invalid and return INT{N}_MIN as a float. Revert any 1309 * inexact exception float64_round_to_int may have raised. 1310 */ 1311 set_float_exception_flags(old_flags | float_flag_invalid, fpst); 1312 return (uint64_t)(0x800 + 1022 + intsize) << 52; 1313 } 1314 1315 float64 HELPER(frint32_d)(float64 f, void *fpst) 1316 { 1317 return frint_d(f, fpst, 32); 1318 } 1319 1320 float64 HELPER(frint64_d)(float64 f, void *fpst) 1321 { 1322 return frint_d(f, fpst, 64); 1323 } 1324 1325 #endif 1326