1 /* 2 * QEMU float support 3 * 4 * The code in this source file is derived from release 2a of the SoftFloat 5 * IEC/IEEE Floating-point Arithmetic Package. Those parts of the code (and 6 * some later contributions) are provided under that license, as detailed below. 7 * It has subsequently been modified by contributors to the QEMU Project, 8 * so some portions are provided under: 9 * the SoftFloat-2a license 10 * the BSD license 11 * GPL-v2-or-later 12 * 13 * Any future contributions to this file after December 1st 2014 will be 14 * taken to be licensed under the Softfloat-2a license unless specifically 15 * indicated otherwise. 16 */ 17 18 /* 19 =============================================================================== 20 This C source file is part of the SoftFloat IEC/IEEE Floating-point 21 Arithmetic Package, Release 2a. 22 23 Written by John R. Hauser. This work was made possible in part by the 24 International Computer Science Institute, located at Suite 600, 1947 Center 25 Street, Berkeley, California 94704. Funding was partially provided by the 26 National Science Foundation under grant MIP-9311980. The original version 27 of this code was written as part of a project to build a fixed-point vector 28 processor in collaboration with the University of California at Berkeley, 29 overseen by Profs. Nelson Morgan and John Wawrzynek. More information 30 is available through the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/ 31 arithmetic/SoftFloat.html'. 32 33 THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort 34 has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT 35 TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO 36 PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY 37 AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE. 38 39 Derivative works are acceptable, even for commercial purposes, so long as 40 (1) they include prominent notice that the work is derivative, and (2) they 41 include prominent notice akin to these four paragraphs for those parts of 42 this code that are retained. 43 44 =============================================================================== 45 */ 46 47 /* BSD licensing: 48 * Copyright (c) 2006, Fabrice Bellard 49 * All rights reserved. 50 * 51 * Redistribution and use in source and binary forms, with or without 52 * modification, are permitted provided that the following conditions are met: 53 * 54 * 1. Redistributions of source code must retain the above copyright notice, 55 * this list of conditions and the following disclaimer. 56 * 57 * 2. Redistributions in binary form must reproduce the above copyright notice, 58 * this list of conditions and the following disclaimer in the documentation 59 * and/or other materials provided with the distribution. 60 * 61 * 3. Neither the name of the copyright holder nor the names of its contributors 62 * may be used to endorse or promote products derived from this software without 63 * specific prior written permission. 64 * 65 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 66 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 67 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 68 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 69 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 70 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 71 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 72 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 73 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 74 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 75 * THE POSSIBILITY OF SUCH DAMAGE. 76 */ 77 78 /* Portions of this work are licensed under the terms of the GNU GPL, 79 * version 2 or later. See the COPYING file in the top-level directory. 80 */ 81 82 /* softfloat (and in particular the code in softfloat-specialize.h) is 83 * target-dependent and needs the TARGET_* macros. 84 */ 85 #include "qemu/osdep.h" 86 #include <math.h> 87 #include "qemu/bitops.h" 88 #include "fpu/softfloat.h" 89 90 /* We only need stdlib for abort() */ 91 92 /*---------------------------------------------------------------------------- 93 | Primitive arithmetic functions, including multi-word arithmetic, and 94 | division and square root approximations. (Can be specialized to target if 95 | desired.) 96 *----------------------------------------------------------------------------*/ 97 #include "fpu/softfloat-macros.h" 98 99 /* 100 * Hardfloat 101 * 102 * Fast emulation of guest FP instructions is challenging for two reasons. 103 * First, FP instruction semantics are similar but not identical, particularly 104 * when handling NaNs. Second, emulating at reasonable speed the guest FP 105 * exception flags is not trivial: reading the host's flags register with a 106 * feclearexcept & fetestexcept pair is slow [slightly slower than soft-fp], 107 * and trapping on every FP exception is not fast nor pleasant to work with. 108 * 109 * We address these challenges by leveraging the host FPU for a subset of the 110 * operations. To do this we expand on the idea presented in this paper: 111 * 112 * Guo, Yu-Chuan, et al. "Translating the ARM Neon and VFP instructions in a 113 * binary translator." Software: Practice and Experience 46.12 (2016):1591-1615. 114 * 115 * The idea is thus to leverage the host FPU to (1) compute FP operations 116 * and (2) identify whether FP exceptions occurred while avoiding 117 * expensive exception flag register accesses. 118 * 119 * An important optimization shown in the paper is that given that exception 120 * flags are rarely cleared by the guest, we can avoid recomputing some flags. 121 * This is particularly useful for the inexact flag, which is very frequently 122 * raised in floating-point workloads. 123 * 124 * We optimize the code further by deferring to soft-fp whenever FP exception 125 * detection might get hairy. Two examples: (1) when at least one operand is 126 * denormal/inf/NaN; (2) when operands are not guaranteed to lead to a 0 result 127 * and the result is < the minimum normal. 128 */ 129 #define GEN_INPUT_FLUSH__NOCHECK(name, soft_t) \ 130 static inline void name(soft_t *a, float_status *s) \ 131 { \ 132 if (unlikely(soft_t ## _is_denormal(*a))) { \ 133 *a = soft_t ## _set_sign(soft_t ## _zero, \ 134 soft_t ## _is_neg(*a)); \ 135 s->float_exception_flags |= float_flag_input_denormal; \ 136 } \ 137 } 138 139 GEN_INPUT_FLUSH__NOCHECK(float32_input_flush__nocheck, float32) 140 GEN_INPUT_FLUSH__NOCHECK(float64_input_flush__nocheck, float64) 141 #undef GEN_INPUT_FLUSH__NOCHECK 142 143 #define GEN_INPUT_FLUSH1(name, soft_t) \ 144 static inline void name(soft_t *a, float_status *s) \ 145 { \ 146 if (likely(!s->flush_inputs_to_zero)) { \ 147 return; \ 148 } \ 149 soft_t ## _input_flush__nocheck(a, s); \ 150 } 151 152 GEN_INPUT_FLUSH1(float32_input_flush1, float32) 153 GEN_INPUT_FLUSH1(float64_input_flush1, float64) 154 #undef GEN_INPUT_FLUSH1 155 156 #define GEN_INPUT_FLUSH2(name, soft_t) \ 157 static inline void name(soft_t *a, soft_t *b, float_status *s) \ 158 { \ 159 if (likely(!s->flush_inputs_to_zero)) { \ 160 return; \ 161 } \ 162 soft_t ## _input_flush__nocheck(a, s); \ 163 soft_t ## _input_flush__nocheck(b, s); \ 164 } 165 166 GEN_INPUT_FLUSH2(float32_input_flush2, float32) 167 GEN_INPUT_FLUSH2(float64_input_flush2, float64) 168 #undef GEN_INPUT_FLUSH2 169 170 #define GEN_INPUT_FLUSH3(name, soft_t) \ 171 static inline void name(soft_t *a, soft_t *b, soft_t *c, float_status *s) \ 172 { \ 173 if (likely(!s->flush_inputs_to_zero)) { \ 174 return; \ 175 } \ 176 soft_t ## _input_flush__nocheck(a, s); \ 177 soft_t ## _input_flush__nocheck(b, s); \ 178 soft_t ## _input_flush__nocheck(c, s); \ 179 } 180 181 GEN_INPUT_FLUSH3(float32_input_flush3, float32) 182 GEN_INPUT_FLUSH3(float64_input_flush3, float64) 183 #undef GEN_INPUT_FLUSH3 184 185 /* 186 * Choose whether to use fpclassify or float32/64_* primitives in the generated 187 * hardfloat functions. Each combination of number of inputs and float size 188 * gets its own value. 189 */ 190 #if defined(__x86_64__) 191 # define QEMU_HARDFLOAT_1F32_USE_FP 0 192 # define QEMU_HARDFLOAT_1F64_USE_FP 1 193 # define QEMU_HARDFLOAT_2F32_USE_FP 0 194 # define QEMU_HARDFLOAT_2F64_USE_FP 1 195 # define QEMU_HARDFLOAT_3F32_USE_FP 0 196 # define QEMU_HARDFLOAT_3F64_USE_FP 1 197 #else 198 # define QEMU_HARDFLOAT_1F32_USE_FP 0 199 # define QEMU_HARDFLOAT_1F64_USE_FP 0 200 # define QEMU_HARDFLOAT_2F32_USE_FP 0 201 # define QEMU_HARDFLOAT_2F64_USE_FP 0 202 # define QEMU_HARDFLOAT_3F32_USE_FP 0 203 # define QEMU_HARDFLOAT_3F64_USE_FP 0 204 #endif 205 206 /* 207 * QEMU_HARDFLOAT_USE_ISINF chooses whether to use isinf() over 208 * float{32,64}_is_infinity when !USE_FP. 209 * On x86_64/aarch64, using the former over the latter can yield a ~6% speedup. 210 * On power64 however, using isinf() reduces fp-bench performance by up to 50%. 211 */ 212 #if defined(__x86_64__) || defined(__aarch64__) 213 # define QEMU_HARDFLOAT_USE_ISINF 1 214 #else 215 # define QEMU_HARDFLOAT_USE_ISINF 0 216 #endif 217 218 /* 219 * Some targets clear the FP flags before most FP operations. This prevents 220 * the use of hardfloat, since hardfloat relies on the inexact flag being 221 * already set. 222 */ 223 #if defined(TARGET_PPC) || defined(__FAST_MATH__) 224 # if defined(__FAST_MATH__) 225 # warning disabling hardfloat due to -ffast-math: hardfloat requires an exact \ 226 IEEE implementation 227 # endif 228 # define QEMU_NO_HARDFLOAT 1 229 # define QEMU_SOFTFLOAT_ATTR QEMU_FLATTEN 230 #else 231 # define QEMU_NO_HARDFLOAT 0 232 # define QEMU_SOFTFLOAT_ATTR QEMU_FLATTEN __attribute__((noinline)) 233 #endif 234 235 static inline bool can_use_fpu(const float_status *s) 236 { 237 if (QEMU_NO_HARDFLOAT) { 238 return false; 239 } 240 return likely(s->float_exception_flags & float_flag_inexact && 241 s->float_rounding_mode == float_round_nearest_even); 242 } 243 244 /* 245 * Hardfloat generation functions. Each operation can have two flavors: 246 * either using softfloat primitives (e.g. float32_is_zero_or_normal) for 247 * most condition checks, or native ones (e.g. fpclassify). 248 * 249 * The flavor is chosen by the callers. Instead of using macros, we rely on the 250 * compiler to propagate constants and inline everything into the callers. 251 * 252 * We only generate functions for operations with two inputs, since only 253 * these are common enough to justify consolidating them into common code. 254 */ 255 256 typedef union { 257 float32 s; 258 float h; 259 } union_float32; 260 261 typedef union { 262 float64 s; 263 double h; 264 } union_float64; 265 266 typedef bool (*f32_check_fn)(union_float32 a, union_float32 b); 267 typedef bool (*f64_check_fn)(union_float64 a, union_float64 b); 268 269 typedef float32 (*soft_f32_op2_fn)(float32 a, float32 b, float_status *s); 270 typedef float64 (*soft_f64_op2_fn)(float64 a, float64 b, float_status *s); 271 typedef float (*hard_f32_op2_fn)(float a, float b); 272 typedef double (*hard_f64_op2_fn)(double a, double b); 273 274 /* 2-input is-zero-or-normal */ 275 static inline bool f32_is_zon2(union_float32 a, union_float32 b) 276 { 277 if (QEMU_HARDFLOAT_2F32_USE_FP) { 278 /* 279 * Not using a temp variable for consecutive fpclassify calls ends up 280 * generating faster code. 281 */ 282 return (fpclassify(a.h) == FP_NORMAL || fpclassify(a.h) == FP_ZERO) && 283 (fpclassify(b.h) == FP_NORMAL || fpclassify(b.h) == FP_ZERO); 284 } 285 return float32_is_zero_or_normal(a.s) && 286 float32_is_zero_or_normal(b.s); 287 } 288 289 static inline bool f64_is_zon2(union_float64 a, union_float64 b) 290 { 291 if (QEMU_HARDFLOAT_2F64_USE_FP) { 292 return (fpclassify(a.h) == FP_NORMAL || fpclassify(a.h) == FP_ZERO) && 293 (fpclassify(b.h) == FP_NORMAL || fpclassify(b.h) == FP_ZERO); 294 } 295 return float64_is_zero_or_normal(a.s) && 296 float64_is_zero_or_normal(b.s); 297 } 298 299 /* 3-input is-zero-or-normal */ 300 static inline 301 bool f32_is_zon3(union_float32 a, union_float32 b, union_float32 c) 302 { 303 if (QEMU_HARDFLOAT_3F32_USE_FP) { 304 return (fpclassify(a.h) == FP_NORMAL || fpclassify(a.h) == FP_ZERO) && 305 (fpclassify(b.h) == FP_NORMAL || fpclassify(b.h) == FP_ZERO) && 306 (fpclassify(c.h) == FP_NORMAL || fpclassify(c.h) == FP_ZERO); 307 } 308 return float32_is_zero_or_normal(a.s) && 309 float32_is_zero_or_normal(b.s) && 310 float32_is_zero_or_normal(c.s); 311 } 312 313 static inline 314 bool f64_is_zon3(union_float64 a, union_float64 b, union_float64 c) 315 { 316 if (QEMU_HARDFLOAT_3F64_USE_FP) { 317 return (fpclassify(a.h) == FP_NORMAL || fpclassify(a.h) == FP_ZERO) && 318 (fpclassify(b.h) == FP_NORMAL || fpclassify(b.h) == FP_ZERO) && 319 (fpclassify(c.h) == FP_NORMAL || fpclassify(c.h) == FP_ZERO); 320 } 321 return float64_is_zero_or_normal(a.s) && 322 float64_is_zero_or_normal(b.s) && 323 float64_is_zero_or_normal(c.s); 324 } 325 326 static inline bool f32_is_inf(union_float32 a) 327 { 328 if (QEMU_HARDFLOAT_USE_ISINF) { 329 return isinf(a.h); 330 } 331 return float32_is_infinity(a.s); 332 } 333 334 static inline bool f64_is_inf(union_float64 a) 335 { 336 if (QEMU_HARDFLOAT_USE_ISINF) { 337 return isinf(a.h); 338 } 339 return float64_is_infinity(a.s); 340 } 341 342 /* Note: @fast_test and @post can be NULL */ 343 static inline float32 344 float32_gen2(float32 xa, float32 xb, float_status *s, 345 hard_f32_op2_fn hard, soft_f32_op2_fn soft, 346 f32_check_fn pre, f32_check_fn post, 347 f32_check_fn fast_test, soft_f32_op2_fn fast_op) 348 { 349 union_float32 ua, ub, ur; 350 351 ua.s = xa; 352 ub.s = xb; 353 354 if (unlikely(!can_use_fpu(s))) { 355 goto soft; 356 } 357 358 float32_input_flush2(&ua.s, &ub.s, s); 359 if (unlikely(!pre(ua, ub))) { 360 goto soft; 361 } 362 if (fast_test && fast_test(ua, ub)) { 363 return fast_op(ua.s, ub.s, s); 364 } 365 366 ur.h = hard(ua.h, ub.h); 367 if (unlikely(f32_is_inf(ur))) { 368 s->float_exception_flags |= float_flag_overflow; 369 } else if (unlikely(fabsf(ur.h) <= FLT_MIN)) { 370 if (post == NULL || post(ua, ub)) { 371 goto soft; 372 } 373 } 374 return ur.s; 375 376 soft: 377 return soft(ua.s, ub.s, s); 378 } 379 380 static inline float64 381 float64_gen2(float64 xa, float64 xb, float_status *s, 382 hard_f64_op2_fn hard, soft_f64_op2_fn soft, 383 f64_check_fn pre, f64_check_fn post, 384 f64_check_fn fast_test, soft_f64_op2_fn fast_op) 385 { 386 union_float64 ua, ub, ur; 387 388 ua.s = xa; 389 ub.s = xb; 390 391 if (unlikely(!can_use_fpu(s))) { 392 goto soft; 393 } 394 395 float64_input_flush2(&ua.s, &ub.s, s); 396 if (unlikely(!pre(ua, ub))) { 397 goto soft; 398 } 399 if (fast_test && fast_test(ua, ub)) { 400 return fast_op(ua.s, ub.s, s); 401 } 402 403 ur.h = hard(ua.h, ub.h); 404 if (unlikely(f64_is_inf(ur))) { 405 s->float_exception_flags |= float_flag_overflow; 406 } else if (unlikely(fabs(ur.h) <= DBL_MIN)) { 407 if (post == NULL || post(ua, ub)) { 408 goto soft; 409 } 410 } 411 return ur.s; 412 413 soft: 414 return soft(ua.s, ub.s, s); 415 } 416 417 /*---------------------------------------------------------------------------- 418 | Returns the fraction bits of the half-precision floating-point value `a'. 419 *----------------------------------------------------------------------------*/ 420 421 static inline uint32_t extractFloat16Frac(float16 a) 422 { 423 return float16_val(a) & 0x3ff; 424 } 425 426 /*---------------------------------------------------------------------------- 427 | Returns the exponent bits of the half-precision floating-point value `a'. 428 *----------------------------------------------------------------------------*/ 429 430 static inline int extractFloat16Exp(float16 a) 431 { 432 return (float16_val(a) >> 10) & 0x1f; 433 } 434 435 /*---------------------------------------------------------------------------- 436 | Returns the fraction bits of the single-precision floating-point value `a'. 437 *----------------------------------------------------------------------------*/ 438 439 static inline uint32_t extractFloat32Frac(float32 a) 440 { 441 return float32_val(a) & 0x007FFFFF; 442 } 443 444 /*---------------------------------------------------------------------------- 445 | Returns the exponent bits of the single-precision floating-point value `a'. 446 *----------------------------------------------------------------------------*/ 447 448 static inline int extractFloat32Exp(float32 a) 449 { 450 return (float32_val(a) >> 23) & 0xFF; 451 } 452 453 /*---------------------------------------------------------------------------- 454 | Returns the sign bit of the single-precision floating-point value `a'. 455 *----------------------------------------------------------------------------*/ 456 457 static inline flag extractFloat32Sign(float32 a) 458 { 459 return float32_val(a) >> 31; 460 } 461 462 /*---------------------------------------------------------------------------- 463 | Returns the fraction bits of the double-precision floating-point value `a'. 464 *----------------------------------------------------------------------------*/ 465 466 static inline uint64_t extractFloat64Frac(float64 a) 467 { 468 return float64_val(a) & LIT64(0x000FFFFFFFFFFFFF); 469 } 470 471 /*---------------------------------------------------------------------------- 472 | Returns the exponent bits of the double-precision floating-point value `a'. 473 *----------------------------------------------------------------------------*/ 474 475 static inline int extractFloat64Exp(float64 a) 476 { 477 return (float64_val(a) >> 52) & 0x7FF; 478 } 479 480 /*---------------------------------------------------------------------------- 481 | Returns the sign bit of the double-precision floating-point value `a'. 482 *----------------------------------------------------------------------------*/ 483 484 static inline flag extractFloat64Sign(float64 a) 485 { 486 return float64_val(a) >> 63; 487 } 488 489 /* 490 * Classify a floating point number. Everything above float_class_qnan 491 * is a NaN so cls >= float_class_qnan is any NaN. 492 */ 493 494 typedef enum __attribute__ ((__packed__)) { 495 float_class_unclassified, 496 float_class_zero, 497 float_class_normal, 498 float_class_inf, 499 float_class_qnan, /* all NaNs from here */ 500 float_class_snan, 501 } FloatClass; 502 503 /* Simple helpers for checking if, or what kind of, NaN we have */ 504 static inline __attribute__((unused)) bool is_nan(FloatClass c) 505 { 506 return unlikely(c >= float_class_qnan); 507 } 508 509 static inline __attribute__((unused)) bool is_snan(FloatClass c) 510 { 511 return c == float_class_snan; 512 } 513 514 static inline __attribute__((unused)) bool is_qnan(FloatClass c) 515 { 516 return c == float_class_qnan; 517 } 518 519 /* 520 * Structure holding all of the decomposed parts of a float. The 521 * exponent is unbiased and the fraction is normalized. All 522 * calculations are done with a 64 bit fraction and then rounded as 523 * appropriate for the final format. 524 * 525 * Thanks to the packed FloatClass a decent compiler should be able to 526 * fit the whole structure into registers and avoid using the stack 527 * for parameter passing. 528 */ 529 530 typedef struct { 531 uint64_t frac; 532 int32_t exp; 533 FloatClass cls; 534 bool sign; 535 } FloatParts; 536 537 #define DECOMPOSED_BINARY_POINT (64 - 2) 538 #define DECOMPOSED_IMPLICIT_BIT (1ull << DECOMPOSED_BINARY_POINT) 539 #define DECOMPOSED_OVERFLOW_BIT (DECOMPOSED_IMPLICIT_BIT << 1) 540 541 /* Structure holding all of the relevant parameters for a format. 542 * exp_size: the size of the exponent field 543 * exp_bias: the offset applied to the exponent field 544 * exp_max: the maximum normalised exponent 545 * frac_size: the size of the fraction field 546 * frac_shift: shift to normalise the fraction with DECOMPOSED_BINARY_POINT 547 * The following are computed based the size of fraction 548 * frac_lsb: least significant bit of fraction 549 * frac_lsbm1: the bit below the least significant bit (for rounding) 550 * round_mask/roundeven_mask: masks used for rounding 551 * The following optional modifiers are available: 552 * arm_althp: handle ARM Alternative Half Precision 553 */ 554 typedef struct { 555 int exp_size; 556 int exp_bias; 557 int exp_max; 558 int frac_size; 559 int frac_shift; 560 uint64_t frac_lsb; 561 uint64_t frac_lsbm1; 562 uint64_t round_mask; 563 uint64_t roundeven_mask; 564 bool arm_althp; 565 } FloatFmt; 566 567 /* Expand fields based on the size of exponent and fraction */ 568 #define FLOAT_PARAMS(E, F) \ 569 .exp_size = E, \ 570 .exp_bias = ((1 << E) - 1) >> 1, \ 571 .exp_max = (1 << E) - 1, \ 572 .frac_size = F, \ 573 .frac_shift = DECOMPOSED_BINARY_POINT - F, \ 574 .frac_lsb = 1ull << (DECOMPOSED_BINARY_POINT - F), \ 575 .frac_lsbm1 = 1ull << ((DECOMPOSED_BINARY_POINT - F) - 1), \ 576 .round_mask = (1ull << (DECOMPOSED_BINARY_POINT - F)) - 1, \ 577 .roundeven_mask = (2ull << (DECOMPOSED_BINARY_POINT - F)) - 1 578 579 static const FloatFmt float16_params = { 580 FLOAT_PARAMS(5, 10) 581 }; 582 583 static const FloatFmt float16_params_ahp = { 584 FLOAT_PARAMS(5, 10), 585 .arm_althp = true 586 }; 587 588 static const FloatFmt float32_params = { 589 FLOAT_PARAMS(8, 23) 590 }; 591 592 static const FloatFmt float64_params = { 593 FLOAT_PARAMS(11, 52) 594 }; 595 596 /* Unpack a float to parts, but do not canonicalize. */ 597 static inline FloatParts unpack_raw(FloatFmt fmt, uint64_t raw) 598 { 599 const int sign_pos = fmt.frac_size + fmt.exp_size; 600 601 return (FloatParts) { 602 .cls = float_class_unclassified, 603 .sign = extract64(raw, sign_pos, 1), 604 .exp = extract64(raw, fmt.frac_size, fmt.exp_size), 605 .frac = extract64(raw, 0, fmt.frac_size), 606 }; 607 } 608 609 static inline FloatParts float16_unpack_raw(float16 f) 610 { 611 return unpack_raw(float16_params, f); 612 } 613 614 static inline FloatParts float32_unpack_raw(float32 f) 615 { 616 return unpack_raw(float32_params, f); 617 } 618 619 static inline FloatParts float64_unpack_raw(float64 f) 620 { 621 return unpack_raw(float64_params, f); 622 } 623 624 /* Pack a float from parts, but do not canonicalize. */ 625 static inline uint64_t pack_raw(FloatFmt fmt, FloatParts p) 626 { 627 const int sign_pos = fmt.frac_size + fmt.exp_size; 628 uint64_t ret = deposit64(p.frac, fmt.frac_size, fmt.exp_size, p.exp); 629 return deposit64(ret, sign_pos, 1, p.sign); 630 } 631 632 static inline float16 float16_pack_raw(FloatParts p) 633 { 634 return make_float16(pack_raw(float16_params, p)); 635 } 636 637 static inline float32 float32_pack_raw(FloatParts p) 638 { 639 return make_float32(pack_raw(float32_params, p)); 640 } 641 642 static inline float64 float64_pack_raw(FloatParts p) 643 { 644 return make_float64(pack_raw(float64_params, p)); 645 } 646 647 /*---------------------------------------------------------------------------- 648 | Functions and definitions to determine: (1) whether tininess for underflow 649 | is detected before or after rounding by default, (2) what (if anything) 650 | happens when exceptions are raised, (3) how signaling NaNs are distinguished 651 | from quiet NaNs, (4) the default generated quiet NaNs, and (5) how NaNs 652 | are propagated from function inputs to output. These details are target- 653 | specific. 654 *----------------------------------------------------------------------------*/ 655 #include "softfloat-specialize.h" 656 657 /* Canonicalize EXP and FRAC, setting CLS. */ 658 static FloatParts sf_canonicalize(FloatParts part, const FloatFmt *parm, 659 float_status *status) 660 { 661 if (part.exp == parm->exp_max && !parm->arm_althp) { 662 if (part.frac == 0) { 663 part.cls = float_class_inf; 664 } else { 665 part.frac <<= parm->frac_shift; 666 part.cls = (parts_is_snan_frac(part.frac, status) 667 ? float_class_snan : float_class_qnan); 668 } 669 } else if (part.exp == 0) { 670 if (likely(part.frac == 0)) { 671 part.cls = float_class_zero; 672 } else if (status->flush_inputs_to_zero) { 673 float_raise(float_flag_input_denormal, status); 674 part.cls = float_class_zero; 675 part.frac = 0; 676 } else { 677 int shift = clz64(part.frac) - 1; 678 part.cls = float_class_normal; 679 part.exp = parm->frac_shift - parm->exp_bias - shift + 1; 680 part.frac <<= shift; 681 } 682 } else { 683 part.cls = float_class_normal; 684 part.exp -= parm->exp_bias; 685 part.frac = DECOMPOSED_IMPLICIT_BIT + (part.frac << parm->frac_shift); 686 } 687 return part; 688 } 689 690 /* Round and uncanonicalize a floating-point number by parts. There 691 * are FRAC_SHIFT bits that may require rounding at the bottom of the 692 * fraction; these bits will be removed. The exponent will be biased 693 * by EXP_BIAS and must be bounded by [EXP_MAX-1, 0]. 694 */ 695 696 static FloatParts round_canonical(FloatParts p, float_status *s, 697 const FloatFmt *parm) 698 { 699 const uint64_t frac_lsb = parm->frac_lsb; 700 const uint64_t frac_lsbm1 = parm->frac_lsbm1; 701 const uint64_t round_mask = parm->round_mask; 702 const uint64_t roundeven_mask = parm->roundeven_mask; 703 const int exp_max = parm->exp_max; 704 const int frac_shift = parm->frac_shift; 705 uint64_t frac, inc; 706 int exp, flags = 0; 707 bool overflow_norm; 708 709 frac = p.frac; 710 exp = p.exp; 711 712 switch (p.cls) { 713 case float_class_normal: 714 switch (s->float_rounding_mode) { 715 case float_round_nearest_even: 716 overflow_norm = false; 717 inc = ((frac & roundeven_mask) != frac_lsbm1 ? frac_lsbm1 : 0); 718 break; 719 case float_round_ties_away: 720 overflow_norm = false; 721 inc = frac_lsbm1; 722 break; 723 case float_round_to_zero: 724 overflow_norm = true; 725 inc = 0; 726 break; 727 case float_round_up: 728 inc = p.sign ? 0 : round_mask; 729 overflow_norm = p.sign; 730 break; 731 case float_round_down: 732 inc = p.sign ? round_mask : 0; 733 overflow_norm = !p.sign; 734 break; 735 case float_round_to_odd: 736 overflow_norm = true; 737 inc = frac & frac_lsb ? 0 : round_mask; 738 break; 739 default: 740 g_assert_not_reached(); 741 } 742 743 exp += parm->exp_bias; 744 if (likely(exp > 0)) { 745 if (frac & round_mask) { 746 flags |= float_flag_inexact; 747 frac += inc; 748 if (frac & DECOMPOSED_OVERFLOW_BIT) { 749 frac >>= 1; 750 exp++; 751 } 752 } 753 frac >>= frac_shift; 754 755 if (parm->arm_althp) { 756 /* ARM Alt HP eschews Inf and NaN for a wider exponent. */ 757 if (unlikely(exp > exp_max)) { 758 /* Overflow. Return the maximum normal. */ 759 flags = float_flag_invalid; 760 exp = exp_max; 761 frac = -1; 762 } 763 } else if (unlikely(exp >= exp_max)) { 764 flags |= float_flag_overflow | float_flag_inexact; 765 if (overflow_norm) { 766 exp = exp_max - 1; 767 frac = -1; 768 } else { 769 p.cls = float_class_inf; 770 goto do_inf; 771 } 772 } 773 } else if (s->flush_to_zero) { 774 flags |= float_flag_output_denormal; 775 p.cls = float_class_zero; 776 goto do_zero; 777 } else { 778 bool is_tiny = (s->float_detect_tininess 779 == float_tininess_before_rounding) 780 || (exp < 0) 781 || !((frac + inc) & DECOMPOSED_OVERFLOW_BIT); 782 783 shift64RightJamming(frac, 1 - exp, &frac); 784 if (frac & round_mask) { 785 /* Need to recompute round-to-even. */ 786 switch (s->float_rounding_mode) { 787 case float_round_nearest_even: 788 inc = ((frac & roundeven_mask) != frac_lsbm1 789 ? frac_lsbm1 : 0); 790 break; 791 case float_round_to_odd: 792 inc = frac & frac_lsb ? 0 : round_mask; 793 break; 794 } 795 flags |= float_flag_inexact; 796 frac += inc; 797 } 798 799 exp = (frac & DECOMPOSED_IMPLICIT_BIT ? 1 : 0); 800 frac >>= frac_shift; 801 802 if (is_tiny && (flags & float_flag_inexact)) { 803 flags |= float_flag_underflow; 804 } 805 if (exp == 0 && frac == 0) { 806 p.cls = float_class_zero; 807 } 808 } 809 break; 810 811 case float_class_zero: 812 do_zero: 813 exp = 0; 814 frac = 0; 815 break; 816 817 case float_class_inf: 818 do_inf: 819 assert(!parm->arm_althp); 820 exp = exp_max; 821 frac = 0; 822 break; 823 824 case float_class_qnan: 825 case float_class_snan: 826 assert(!parm->arm_althp); 827 exp = exp_max; 828 frac >>= parm->frac_shift; 829 break; 830 831 default: 832 g_assert_not_reached(); 833 } 834 835 float_raise(flags, s); 836 p.exp = exp; 837 p.frac = frac; 838 return p; 839 } 840 841 /* Explicit FloatFmt version */ 842 static FloatParts float16a_unpack_canonical(float16 f, float_status *s, 843 const FloatFmt *params) 844 { 845 return sf_canonicalize(float16_unpack_raw(f), params, s); 846 } 847 848 static FloatParts float16_unpack_canonical(float16 f, float_status *s) 849 { 850 return float16a_unpack_canonical(f, s, &float16_params); 851 } 852 853 static float16 float16a_round_pack_canonical(FloatParts p, float_status *s, 854 const FloatFmt *params) 855 { 856 return float16_pack_raw(round_canonical(p, s, params)); 857 } 858 859 static float16 float16_round_pack_canonical(FloatParts p, float_status *s) 860 { 861 return float16a_round_pack_canonical(p, s, &float16_params); 862 } 863 864 static FloatParts float32_unpack_canonical(float32 f, float_status *s) 865 { 866 return sf_canonicalize(float32_unpack_raw(f), &float32_params, s); 867 } 868 869 static float32 float32_round_pack_canonical(FloatParts p, float_status *s) 870 { 871 return float32_pack_raw(round_canonical(p, s, &float32_params)); 872 } 873 874 static FloatParts float64_unpack_canonical(float64 f, float_status *s) 875 { 876 return sf_canonicalize(float64_unpack_raw(f), &float64_params, s); 877 } 878 879 static float64 float64_round_pack_canonical(FloatParts p, float_status *s) 880 { 881 return float64_pack_raw(round_canonical(p, s, &float64_params)); 882 } 883 884 static FloatParts return_nan(FloatParts a, float_status *s) 885 { 886 switch (a.cls) { 887 case float_class_snan: 888 s->float_exception_flags |= float_flag_invalid; 889 a = parts_silence_nan(a, s); 890 /* fall through */ 891 case float_class_qnan: 892 if (s->default_nan_mode) { 893 return parts_default_nan(s); 894 } 895 break; 896 897 default: 898 g_assert_not_reached(); 899 } 900 return a; 901 } 902 903 static FloatParts pick_nan(FloatParts a, FloatParts b, float_status *s) 904 { 905 if (is_snan(a.cls) || is_snan(b.cls)) { 906 s->float_exception_flags |= float_flag_invalid; 907 } 908 909 if (s->default_nan_mode) { 910 return parts_default_nan(s); 911 } else { 912 if (pickNaN(a.cls, b.cls, 913 a.frac > b.frac || 914 (a.frac == b.frac && a.sign < b.sign))) { 915 a = b; 916 } 917 if (is_snan(a.cls)) { 918 return parts_silence_nan(a, s); 919 } 920 } 921 return a; 922 } 923 924 static FloatParts pick_nan_muladd(FloatParts a, FloatParts b, FloatParts c, 925 bool inf_zero, float_status *s) 926 { 927 int which; 928 929 if (is_snan(a.cls) || is_snan(b.cls) || is_snan(c.cls)) { 930 s->float_exception_flags |= float_flag_invalid; 931 } 932 933 which = pickNaNMulAdd(a.cls, b.cls, c.cls, inf_zero, s); 934 935 if (s->default_nan_mode) { 936 /* Note that this check is after pickNaNMulAdd so that function 937 * has an opportunity to set the Invalid flag. 938 */ 939 which = 3; 940 } 941 942 switch (which) { 943 case 0: 944 break; 945 case 1: 946 a = b; 947 break; 948 case 2: 949 a = c; 950 break; 951 case 3: 952 return parts_default_nan(s); 953 default: 954 g_assert_not_reached(); 955 } 956 957 if (is_snan(a.cls)) { 958 return parts_silence_nan(a, s); 959 } 960 return a; 961 } 962 963 /* 964 * Returns the result of adding or subtracting the values of the 965 * floating-point values `a' and `b'. The operation is performed 966 * according to the IEC/IEEE Standard for Binary Floating-Point 967 * Arithmetic. 968 */ 969 970 static FloatParts addsub_floats(FloatParts a, FloatParts b, bool subtract, 971 float_status *s) 972 { 973 bool a_sign = a.sign; 974 bool b_sign = b.sign ^ subtract; 975 976 if (a_sign != b_sign) { 977 /* Subtraction */ 978 979 if (a.cls == float_class_normal && b.cls == float_class_normal) { 980 if (a.exp > b.exp || (a.exp == b.exp && a.frac >= b.frac)) { 981 shift64RightJamming(b.frac, a.exp - b.exp, &b.frac); 982 a.frac = a.frac - b.frac; 983 } else { 984 shift64RightJamming(a.frac, b.exp - a.exp, &a.frac); 985 a.frac = b.frac - a.frac; 986 a.exp = b.exp; 987 a_sign ^= 1; 988 } 989 990 if (a.frac == 0) { 991 a.cls = float_class_zero; 992 a.sign = s->float_rounding_mode == float_round_down; 993 } else { 994 int shift = clz64(a.frac) - 1; 995 a.frac = a.frac << shift; 996 a.exp = a.exp - shift; 997 a.sign = a_sign; 998 } 999 return a; 1000 } 1001 if (is_nan(a.cls) || is_nan(b.cls)) { 1002 return pick_nan(a, b, s); 1003 } 1004 if (a.cls == float_class_inf) { 1005 if (b.cls == float_class_inf) { 1006 float_raise(float_flag_invalid, s); 1007 return parts_default_nan(s); 1008 } 1009 return a; 1010 } 1011 if (a.cls == float_class_zero && b.cls == float_class_zero) { 1012 a.sign = s->float_rounding_mode == float_round_down; 1013 return a; 1014 } 1015 if (a.cls == float_class_zero || b.cls == float_class_inf) { 1016 b.sign = a_sign ^ 1; 1017 return b; 1018 } 1019 if (b.cls == float_class_zero) { 1020 return a; 1021 } 1022 } else { 1023 /* Addition */ 1024 if (a.cls == float_class_normal && b.cls == float_class_normal) { 1025 if (a.exp > b.exp) { 1026 shift64RightJamming(b.frac, a.exp - b.exp, &b.frac); 1027 } else if (a.exp < b.exp) { 1028 shift64RightJamming(a.frac, b.exp - a.exp, &a.frac); 1029 a.exp = b.exp; 1030 } 1031 a.frac += b.frac; 1032 if (a.frac & DECOMPOSED_OVERFLOW_BIT) { 1033 shift64RightJamming(a.frac, 1, &a.frac); 1034 a.exp += 1; 1035 } 1036 return a; 1037 } 1038 if (is_nan(a.cls) || is_nan(b.cls)) { 1039 return pick_nan(a, b, s); 1040 } 1041 if (a.cls == float_class_inf || b.cls == float_class_zero) { 1042 return a; 1043 } 1044 if (b.cls == float_class_inf || a.cls == float_class_zero) { 1045 b.sign = b_sign; 1046 return b; 1047 } 1048 } 1049 g_assert_not_reached(); 1050 } 1051 1052 /* 1053 * Returns the result of adding or subtracting the floating-point 1054 * values `a' and `b'. The operation is performed according to the 1055 * IEC/IEEE Standard for Binary Floating-Point Arithmetic. 1056 */ 1057 1058 float16 QEMU_FLATTEN float16_add(float16 a, float16 b, float_status *status) 1059 { 1060 FloatParts pa = float16_unpack_canonical(a, status); 1061 FloatParts pb = float16_unpack_canonical(b, status); 1062 FloatParts pr = addsub_floats(pa, pb, false, status); 1063 1064 return float16_round_pack_canonical(pr, status); 1065 } 1066 1067 float16 QEMU_FLATTEN float16_sub(float16 a, float16 b, float_status *status) 1068 { 1069 FloatParts pa = float16_unpack_canonical(a, status); 1070 FloatParts pb = float16_unpack_canonical(b, status); 1071 FloatParts pr = addsub_floats(pa, pb, true, status); 1072 1073 return float16_round_pack_canonical(pr, status); 1074 } 1075 1076 static float32 QEMU_SOFTFLOAT_ATTR 1077 soft_f32_addsub(float32 a, float32 b, bool subtract, float_status *status) 1078 { 1079 FloatParts pa = float32_unpack_canonical(a, status); 1080 FloatParts pb = float32_unpack_canonical(b, status); 1081 FloatParts pr = addsub_floats(pa, pb, subtract, status); 1082 1083 return float32_round_pack_canonical(pr, status); 1084 } 1085 1086 static inline float32 soft_f32_add(float32 a, float32 b, float_status *status) 1087 { 1088 return soft_f32_addsub(a, b, false, status); 1089 } 1090 1091 static inline float32 soft_f32_sub(float32 a, float32 b, float_status *status) 1092 { 1093 return soft_f32_addsub(a, b, true, status); 1094 } 1095 1096 static float64 QEMU_SOFTFLOAT_ATTR 1097 soft_f64_addsub(float64 a, float64 b, bool subtract, float_status *status) 1098 { 1099 FloatParts pa = float64_unpack_canonical(a, status); 1100 FloatParts pb = float64_unpack_canonical(b, status); 1101 FloatParts pr = addsub_floats(pa, pb, subtract, status); 1102 1103 return float64_round_pack_canonical(pr, status); 1104 } 1105 1106 static inline float64 soft_f64_add(float64 a, float64 b, float_status *status) 1107 { 1108 return soft_f64_addsub(a, b, false, status); 1109 } 1110 1111 static inline float64 soft_f64_sub(float64 a, float64 b, float_status *status) 1112 { 1113 return soft_f64_addsub(a, b, true, status); 1114 } 1115 1116 static float hard_f32_add(float a, float b) 1117 { 1118 return a + b; 1119 } 1120 1121 static float hard_f32_sub(float a, float b) 1122 { 1123 return a - b; 1124 } 1125 1126 static double hard_f64_add(double a, double b) 1127 { 1128 return a + b; 1129 } 1130 1131 static double hard_f64_sub(double a, double b) 1132 { 1133 return a - b; 1134 } 1135 1136 static bool f32_addsub_post(union_float32 a, union_float32 b) 1137 { 1138 if (QEMU_HARDFLOAT_2F32_USE_FP) { 1139 return !(fpclassify(a.h) == FP_ZERO && fpclassify(b.h) == FP_ZERO); 1140 } 1141 return !(float32_is_zero(a.s) && float32_is_zero(b.s)); 1142 } 1143 1144 static bool f64_addsub_post(union_float64 a, union_float64 b) 1145 { 1146 if (QEMU_HARDFLOAT_2F64_USE_FP) { 1147 return !(fpclassify(a.h) == FP_ZERO && fpclassify(b.h) == FP_ZERO); 1148 } else { 1149 return !(float64_is_zero(a.s) && float64_is_zero(b.s)); 1150 } 1151 } 1152 1153 static float32 float32_addsub(float32 a, float32 b, float_status *s, 1154 hard_f32_op2_fn hard, soft_f32_op2_fn soft) 1155 { 1156 return float32_gen2(a, b, s, hard, soft, 1157 f32_is_zon2, f32_addsub_post, NULL, NULL); 1158 } 1159 1160 static float64 float64_addsub(float64 a, float64 b, float_status *s, 1161 hard_f64_op2_fn hard, soft_f64_op2_fn soft) 1162 { 1163 return float64_gen2(a, b, s, hard, soft, 1164 f64_is_zon2, f64_addsub_post, NULL, NULL); 1165 } 1166 1167 float32 QEMU_FLATTEN 1168 float32_add(float32 a, float32 b, float_status *s) 1169 { 1170 return float32_addsub(a, b, s, hard_f32_add, soft_f32_add); 1171 } 1172 1173 float32 QEMU_FLATTEN 1174 float32_sub(float32 a, float32 b, float_status *s) 1175 { 1176 return float32_addsub(a, b, s, hard_f32_sub, soft_f32_sub); 1177 } 1178 1179 float64 QEMU_FLATTEN 1180 float64_add(float64 a, float64 b, float_status *s) 1181 { 1182 return float64_addsub(a, b, s, hard_f64_add, soft_f64_add); 1183 } 1184 1185 float64 QEMU_FLATTEN 1186 float64_sub(float64 a, float64 b, float_status *s) 1187 { 1188 return float64_addsub(a, b, s, hard_f64_sub, soft_f64_sub); 1189 } 1190 1191 /* 1192 * Returns the result of multiplying the floating-point values `a' and 1193 * `b'. The operation is performed according to the IEC/IEEE Standard 1194 * for Binary Floating-Point Arithmetic. 1195 */ 1196 1197 static FloatParts mul_floats(FloatParts a, FloatParts b, float_status *s) 1198 { 1199 bool sign = a.sign ^ b.sign; 1200 1201 if (a.cls == float_class_normal && b.cls == float_class_normal) { 1202 uint64_t hi, lo; 1203 int exp = a.exp + b.exp; 1204 1205 mul64To128(a.frac, b.frac, &hi, &lo); 1206 shift128RightJamming(hi, lo, DECOMPOSED_BINARY_POINT, &hi, &lo); 1207 if (lo & DECOMPOSED_OVERFLOW_BIT) { 1208 shift64RightJamming(lo, 1, &lo); 1209 exp += 1; 1210 } 1211 1212 /* Re-use a */ 1213 a.exp = exp; 1214 a.sign = sign; 1215 a.frac = lo; 1216 return a; 1217 } 1218 /* handle all the NaN cases */ 1219 if (is_nan(a.cls) || is_nan(b.cls)) { 1220 return pick_nan(a, b, s); 1221 } 1222 /* Inf * Zero == NaN */ 1223 if ((a.cls == float_class_inf && b.cls == float_class_zero) || 1224 (a.cls == float_class_zero && b.cls == float_class_inf)) { 1225 s->float_exception_flags |= float_flag_invalid; 1226 return parts_default_nan(s); 1227 } 1228 /* Multiply by 0 or Inf */ 1229 if (a.cls == float_class_inf || a.cls == float_class_zero) { 1230 a.sign = sign; 1231 return a; 1232 } 1233 if (b.cls == float_class_inf || b.cls == float_class_zero) { 1234 b.sign = sign; 1235 return b; 1236 } 1237 g_assert_not_reached(); 1238 } 1239 1240 float16 QEMU_FLATTEN float16_mul(float16 a, float16 b, float_status *status) 1241 { 1242 FloatParts pa = float16_unpack_canonical(a, status); 1243 FloatParts pb = float16_unpack_canonical(b, status); 1244 FloatParts pr = mul_floats(pa, pb, status); 1245 1246 return float16_round_pack_canonical(pr, status); 1247 } 1248 1249 static float32 QEMU_SOFTFLOAT_ATTR 1250 soft_f32_mul(float32 a, float32 b, float_status *status) 1251 { 1252 FloatParts pa = float32_unpack_canonical(a, status); 1253 FloatParts pb = float32_unpack_canonical(b, status); 1254 FloatParts pr = mul_floats(pa, pb, status); 1255 1256 return float32_round_pack_canonical(pr, status); 1257 } 1258 1259 static float64 QEMU_SOFTFLOAT_ATTR 1260 soft_f64_mul(float64 a, float64 b, float_status *status) 1261 { 1262 FloatParts pa = float64_unpack_canonical(a, status); 1263 FloatParts pb = float64_unpack_canonical(b, status); 1264 FloatParts pr = mul_floats(pa, pb, status); 1265 1266 return float64_round_pack_canonical(pr, status); 1267 } 1268 1269 static float hard_f32_mul(float a, float b) 1270 { 1271 return a * b; 1272 } 1273 1274 static double hard_f64_mul(double a, double b) 1275 { 1276 return a * b; 1277 } 1278 1279 static bool f32_mul_fast_test(union_float32 a, union_float32 b) 1280 { 1281 return float32_is_zero(a.s) || float32_is_zero(b.s); 1282 } 1283 1284 static bool f64_mul_fast_test(union_float64 a, union_float64 b) 1285 { 1286 return float64_is_zero(a.s) || float64_is_zero(b.s); 1287 } 1288 1289 static float32 f32_mul_fast_op(float32 a, float32 b, float_status *s) 1290 { 1291 bool signbit = float32_is_neg(a) ^ float32_is_neg(b); 1292 1293 return float32_set_sign(float32_zero, signbit); 1294 } 1295 1296 static float64 f64_mul_fast_op(float64 a, float64 b, float_status *s) 1297 { 1298 bool signbit = float64_is_neg(a) ^ float64_is_neg(b); 1299 1300 return float64_set_sign(float64_zero, signbit); 1301 } 1302 1303 float32 QEMU_FLATTEN 1304 float32_mul(float32 a, float32 b, float_status *s) 1305 { 1306 return float32_gen2(a, b, s, hard_f32_mul, soft_f32_mul, 1307 f32_is_zon2, NULL, f32_mul_fast_test, f32_mul_fast_op); 1308 } 1309 1310 float64 QEMU_FLATTEN 1311 float64_mul(float64 a, float64 b, float_status *s) 1312 { 1313 return float64_gen2(a, b, s, hard_f64_mul, soft_f64_mul, 1314 f64_is_zon2, NULL, f64_mul_fast_test, f64_mul_fast_op); 1315 } 1316 1317 /* 1318 * Returns the result of multiplying the floating-point values `a' and 1319 * `b' then adding 'c', with no intermediate rounding step after the 1320 * multiplication. The operation is performed according to the 1321 * IEC/IEEE Standard for Binary Floating-Point Arithmetic 754-2008. 1322 * The flags argument allows the caller to select negation of the 1323 * addend, the intermediate product, or the final result. (The 1324 * difference between this and having the caller do a separate 1325 * negation is that negating externally will flip the sign bit on 1326 * NaNs.) 1327 */ 1328 1329 static FloatParts muladd_floats(FloatParts a, FloatParts b, FloatParts c, 1330 int flags, float_status *s) 1331 { 1332 bool inf_zero = ((1 << a.cls) | (1 << b.cls)) == 1333 ((1 << float_class_inf) | (1 << float_class_zero)); 1334 bool p_sign; 1335 bool sign_flip = flags & float_muladd_negate_result; 1336 FloatClass p_class; 1337 uint64_t hi, lo; 1338 int p_exp; 1339 1340 /* It is implementation-defined whether the cases of (0,inf,qnan) 1341 * and (inf,0,qnan) raise InvalidOperation or not (and what QNaN 1342 * they return if they do), so we have to hand this information 1343 * off to the target-specific pick-a-NaN routine. 1344 */ 1345 if (is_nan(a.cls) || is_nan(b.cls) || is_nan(c.cls)) { 1346 return pick_nan_muladd(a, b, c, inf_zero, s); 1347 } 1348 1349 if (inf_zero) { 1350 s->float_exception_flags |= float_flag_invalid; 1351 return parts_default_nan(s); 1352 } 1353 1354 if (flags & float_muladd_negate_c) { 1355 c.sign ^= 1; 1356 } 1357 1358 p_sign = a.sign ^ b.sign; 1359 1360 if (flags & float_muladd_negate_product) { 1361 p_sign ^= 1; 1362 } 1363 1364 if (a.cls == float_class_inf || b.cls == float_class_inf) { 1365 p_class = float_class_inf; 1366 } else if (a.cls == float_class_zero || b.cls == float_class_zero) { 1367 p_class = float_class_zero; 1368 } else { 1369 p_class = float_class_normal; 1370 } 1371 1372 if (c.cls == float_class_inf) { 1373 if (p_class == float_class_inf && p_sign != c.sign) { 1374 s->float_exception_flags |= float_flag_invalid; 1375 return parts_default_nan(s); 1376 } else { 1377 a.cls = float_class_inf; 1378 a.sign = c.sign ^ sign_flip; 1379 return a; 1380 } 1381 } 1382 1383 if (p_class == float_class_inf) { 1384 a.cls = float_class_inf; 1385 a.sign = p_sign ^ sign_flip; 1386 return a; 1387 } 1388 1389 if (p_class == float_class_zero) { 1390 if (c.cls == float_class_zero) { 1391 if (p_sign != c.sign) { 1392 p_sign = s->float_rounding_mode == float_round_down; 1393 } 1394 c.sign = p_sign; 1395 } else if (flags & float_muladd_halve_result) { 1396 c.exp -= 1; 1397 } 1398 c.sign ^= sign_flip; 1399 return c; 1400 } 1401 1402 /* a & b should be normals now... */ 1403 assert(a.cls == float_class_normal && 1404 b.cls == float_class_normal); 1405 1406 p_exp = a.exp + b.exp; 1407 1408 /* Multiply of 2 62-bit numbers produces a (2*62) == 124-bit 1409 * result. 1410 */ 1411 mul64To128(a.frac, b.frac, &hi, &lo); 1412 /* binary point now at bit 124 */ 1413 1414 /* check for overflow */ 1415 if (hi & (1ULL << (DECOMPOSED_BINARY_POINT * 2 + 1 - 64))) { 1416 shift128RightJamming(hi, lo, 1, &hi, &lo); 1417 p_exp += 1; 1418 } 1419 1420 /* + add/sub */ 1421 if (c.cls == float_class_zero) { 1422 /* move binary point back to 62 */ 1423 shift128RightJamming(hi, lo, DECOMPOSED_BINARY_POINT, &hi, &lo); 1424 } else { 1425 int exp_diff = p_exp - c.exp; 1426 if (p_sign == c.sign) { 1427 /* Addition */ 1428 if (exp_diff <= 0) { 1429 shift128RightJamming(hi, lo, 1430 DECOMPOSED_BINARY_POINT - exp_diff, 1431 &hi, &lo); 1432 lo += c.frac; 1433 p_exp = c.exp; 1434 } else { 1435 uint64_t c_hi, c_lo; 1436 /* shift c to the same binary point as the product (124) */ 1437 c_hi = c.frac >> 2; 1438 c_lo = 0; 1439 shift128RightJamming(c_hi, c_lo, 1440 exp_diff, 1441 &c_hi, &c_lo); 1442 add128(hi, lo, c_hi, c_lo, &hi, &lo); 1443 /* move binary point back to 62 */ 1444 shift128RightJamming(hi, lo, DECOMPOSED_BINARY_POINT, &hi, &lo); 1445 } 1446 1447 if (lo & DECOMPOSED_OVERFLOW_BIT) { 1448 shift64RightJamming(lo, 1, &lo); 1449 p_exp += 1; 1450 } 1451 1452 } else { 1453 /* Subtraction */ 1454 uint64_t c_hi, c_lo; 1455 /* make C binary point match product at bit 124 */ 1456 c_hi = c.frac >> 2; 1457 c_lo = 0; 1458 1459 if (exp_diff <= 0) { 1460 shift128RightJamming(hi, lo, -exp_diff, &hi, &lo); 1461 if (exp_diff == 0 1462 && 1463 (hi > c_hi || (hi == c_hi && lo >= c_lo))) { 1464 sub128(hi, lo, c_hi, c_lo, &hi, &lo); 1465 } else { 1466 sub128(c_hi, c_lo, hi, lo, &hi, &lo); 1467 p_sign ^= 1; 1468 p_exp = c.exp; 1469 } 1470 } else { 1471 shift128RightJamming(c_hi, c_lo, 1472 exp_diff, 1473 &c_hi, &c_lo); 1474 sub128(hi, lo, c_hi, c_lo, &hi, &lo); 1475 } 1476 1477 if (hi == 0 && lo == 0) { 1478 a.cls = float_class_zero; 1479 a.sign = s->float_rounding_mode == float_round_down; 1480 a.sign ^= sign_flip; 1481 return a; 1482 } else { 1483 int shift; 1484 if (hi != 0) { 1485 shift = clz64(hi); 1486 } else { 1487 shift = clz64(lo) + 64; 1488 } 1489 /* Normalizing to a binary point of 124 is the 1490 correct adjust for the exponent. However since we're 1491 shifting, we might as well put the binary point back 1492 at 62 where we really want it. Therefore shift as 1493 if we're leaving 1 bit at the top of the word, but 1494 adjust the exponent as if we're leaving 3 bits. */ 1495 shift -= 1; 1496 if (shift >= 64) { 1497 lo = lo << (shift - 64); 1498 } else { 1499 hi = (hi << shift) | (lo >> (64 - shift)); 1500 lo = hi | ((lo << shift) != 0); 1501 } 1502 p_exp -= shift - 2; 1503 } 1504 } 1505 } 1506 1507 if (flags & float_muladd_halve_result) { 1508 p_exp -= 1; 1509 } 1510 1511 /* finally prepare our result */ 1512 a.cls = float_class_normal; 1513 a.sign = p_sign ^ sign_flip; 1514 a.exp = p_exp; 1515 a.frac = lo; 1516 1517 return a; 1518 } 1519 1520 float16 QEMU_FLATTEN float16_muladd(float16 a, float16 b, float16 c, 1521 int flags, float_status *status) 1522 { 1523 FloatParts pa = float16_unpack_canonical(a, status); 1524 FloatParts pb = float16_unpack_canonical(b, status); 1525 FloatParts pc = float16_unpack_canonical(c, status); 1526 FloatParts pr = muladd_floats(pa, pb, pc, flags, status); 1527 1528 return float16_round_pack_canonical(pr, status); 1529 } 1530 1531 static float32 QEMU_SOFTFLOAT_ATTR 1532 soft_f32_muladd(float32 a, float32 b, float32 c, int flags, 1533 float_status *status) 1534 { 1535 FloatParts pa = float32_unpack_canonical(a, status); 1536 FloatParts pb = float32_unpack_canonical(b, status); 1537 FloatParts pc = float32_unpack_canonical(c, status); 1538 FloatParts pr = muladd_floats(pa, pb, pc, flags, status); 1539 1540 return float32_round_pack_canonical(pr, status); 1541 } 1542 1543 static float64 QEMU_SOFTFLOAT_ATTR 1544 soft_f64_muladd(float64 a, float64 b, float64 c, int flags, 1545 float_status *status) 1546 { 1547 FloatParts pa = float64_unpack_canonical(a, status); 1548 FloatParts pb = float64_unpack_canonical(b, status); 1549 FloatParts pc = float64_unpack_canonical(c, status); 1550 FloatParts pr = muladd_floats(pa, pb, pc, flags, status); 1551 1552 return float64_round_pack_canonical(pr, status); 1553 } 1554 1555 static bool force_soft_fma; 1556 1557 float32 QEMU_FLATTEN 1558 float32_muladd(float32 xa, float32 xb, float32 xc, int flags, float_status *s) 1559 { 1560 union_float32 ua, ub, uc, ur; 1561 1562 ua.s = xa; 1563 ub.s = xb; 1564 uc.s = xc; 1565 1566 if (unlikely(!can_use_fpu(s))) { 1567 goto soft; 1568 } 1569 if (unlikely(flags & float_muladd_halve_result)) { 1570 goto soft; 1571 } 1572 1573 float32_input_flush3(&ua.s, &ub.s, &uc.s, s); 1574 if (unlikely(!f32_is_zon3(ua, ub, uc))) { 1575 goto soft; 1576 } 1577 1578 if (unlikely(force_soft_fma)) { 1579 goto soft; 1580 } 1581 1582 /* 1583 * When (a || b) == 0, there's no need to check for under/over flow, 1584 * since we know the addend is (normal || 0) and the product is 0. 1585 */ 1586 if (float32_is_zero(ua.s) || float32_is_zero(ub.s)) { 1587 union_float32 up; 1588 bool prod_sign; 1589 1590 prod_sign = float32_is_neg(ua.s) ^ float32_is_neg(ub.s); 1591 prod_sign ^= !!(flags & float_muladd_negate_product); 1592 up.s = float32_set_sign(float32_zero, prod_sign); 1593 1594 if (flags & float_muladd_negate_c) { 1595 uc.h = -uc.h; 1596 } 1597 ur.h = up.h + uc.h; 1598 } else { 1599 union_float32 ua_orig = ua; 1600 union_float32 uc_orig = uc; 1601 1602 if (flags & float_muladd_negate_product) { 1603 ua.h = -ua.h; 1604 } 1605 if (flags & float_muladd_negate_c) { 1606 uc.h = -uc.h; 1607 } 1608 1609 ur.h = fmaf(ua.h, ub.h, uc.h); 1610 1611 if (unlikely(f32_is_inf(ur))) { 1612 s->float_exception_flags |= float_flag_overflow; 1613 } else if (unlikely(fabsf(ur.h) <= FLT_MIN)) { 1614 ua = ua_orig; 1615 uc = uc_orig; 1616 goto soft; 1617 } 1618 } 1619 if (flags & float_muladd_negate_result) { 1620 return float32_chs(ur.s); 1621 } 1622 return ur.s; 1623 1624 soft: 1625 return soft_f32_muladd(ua.s, ub.s, uc.s, flags, s); 1626 } 1627 1628 float64 QEMU_FLATTEN 1629 float64_muladd(float64 xa, float64 xb, float64 xc, int flags, float_status *s) 1630 { 1631 union_float64 ua, ub, uc, ur; 1632 1633 ua.s = xa; 1634 ub.s = xb; 1635 uc.s = xc; 1636 1637 if (unlikely(!can_use_fpu(s))) { 1638 goto soft; 1639 } 1640 if (unlikely(flags & float_muladd_halve_result)) { 1641 goto soft; 1642 } 1643 1644 float64_input_flush3(&ua.s, &ub.s, &uc.s, s); 1645 if (unlikely(!f64_is_zon3(ua, ub, uc))) { 1646 goto soft; 1647 } 1648 1649 if (unlikely(force_soft_fma)) { 1650 goto soft; 1651 } 1652 1653 /* 1654 * When (a || b) == 0, there's no need to check for under/over flow, 1655 * since we know the addend is (normal || 0) and the product is 0. 1656 */ 1657 if (float64_is_zero(ua.s) || float64_is_zero(ub.s)) { 1658 union_float64 up; 1659 bool prod_sign; 1660 1661 prod_sign = float64_is_neg(ua.s) ^ float64_is_neg(ub.s); 1662 prod_sign ^= !!(flags & float_muladd_negate_product); 1663 up.s = float64_set_sign(float64_zero, prod_sign); 1664 1665 if (flags & float_muladd_negate_c) { 1666 uc.h = -uc.h; 1667 } 1668 ur.h = up.h + uc.h; 1669 } else { 1670 union_float64 ua_orig = ua; 1671 union_float64 uc_orig = uc; 1672 1673 if (flags & float_muladd_negate_product) { 1674 ua.h = -ua.h; 1675 } 1676 if (flags & float_muladd_negate_c) { 1677 uc.h = -uc.h; 1678 } 1679 1680 ur.h = fma(ua.h, ub.h, uc.h); 1681 1682 if (unlikely(f64_is_inf(ur))) { 1683 s->float_exception_flags |= float_flag_overflow; 1684 } else if (unlikely(fabs(ur.h) <= FLT_MIN)) { 1685 ua = ua_orig; 1686 uc = uc_orig; 1687 goto soft; 1688 } 1689 } 1690 if (flags & float_muladd_negate_result) { 1691 return float64_chs(ur.s); 1692 } 1693 return ur.s; 1694 1695 soft: 1696 return soft_f64_muladd(ua.s, ub.s, uc.s, flags, s); 1697 } 1698 1699 /* 1700 * Returns the result of dividing the floating-point value `a' by the 1701 * corresponding value `b'. The operation is performed according to 1702 * the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 1703 */ 1704 1705 static FloatParts div_floats(FloatParts a, FloatParts b, float_status *s) 1706 { 1707 bool sign = a.sign ^ b.sign; 1708 1709 if (a.cls == float_class_normal && b.cls == float_class_normal) { 1710 uint64_t n0, n1, q, r; 1711 int exp = a.exp - b.exp; 1712 1713 /* 1714 * We want a 2*N / N-bit division to produce exactly an N-bit 1715 * result, so that we do not lose any precision and so that we 1716 * do not have to renormalize afterward. If A.frac < B.frac, 1717 * then division would produce an (N-1)-bit result; shift A left 1718 * by one to produce the an N-bit result, and decrement the 1719 * exponent to match. 1720 * 1721 * The udiv_qrnnd algorithm that we're using requires normalization, 1722 * i.e. the msb of the denominator must be set. Since we know that 1723 * DECOMPOSED_BINARY_POINT is msb-1, the inputs must be shifted left 1724 * by one (more), and the remainder must be shifted right by one. 1725 */ 1726 if (a.frac < b.frac) { 1727 exp -= 1; 1728 shift128Left(0, a.frac, DECOMPOSED_BINARY_POINT + 2, &n1, &n0); 1729 } else { 1730 shift128Left(0, a.frac, DECOMPOSED_BINARY_POINT + 1, &n1, &n0); 1731 } 1732 q = udiv_qrnnd(&r, n1, n0, b.frac << 1); 1733 1734 /* 1735 * Set lsb if there is a remainder, to set inexact. 1736 * As mentioned above, to find the actual value of the remainder we 1737 * would need to shift right, but (1) we are only concerned about 1738 * non-zero-ness, and (2) the remainder will always be even because 1739 * both inputs to the division primitive are even. 1740 */ 1741 a.frac = q | (r != 0); 1742 a.sign = sign; 1743 a.exp = exp; 1744 return a; 1745 } 1746 /* handle all the NaN cases */ 1747 if (is_nan(a.cls) || is_nan(b.cls)) { 1748 return pick_nan(a, b, s); 1749 } 1750 /* 0/0 or Inf/Inf */ 1751 if (a.cls == b.cls 1752 && 1753 (a.cls == float_class_inf || a.cls == float_class_zero)) { 1754 s->float_exception_flags |= float_flag_invalid; 1755 return parts_default_nan(s); 1756 } 1757 /* Inf / x or 0 / x */ 1758 if (a.cls == float_class_inf || a.cls == float_class_zero) { 1759 a.sign = sign; 1760 return a; 1761 } 1762 /* Div 0 => Inf */ 1763 if (b.cls == float_class_zero) { 1764 s->float_exception_flags |= float_flag_divbyzero; 1765 a.cls = float_class_inf; 1766 a.sign = sign; 1767 return a; 1768 } 1769 /* Div by Inf */ 1770 if (b.cls == float_class_inf) { 1771 a.cls = float_class_zero; 1772 a.sign = sign; 1773 return a; 1774 } 1775 g_assert_not_reached(); 1776 } 1777 1778 float16 float16_div(float16 a, float16 b, float_status *status) 1779 { 1780 FloatParts pa = float16_unpack_canonical(a, status); 1781 FloatParts pb = float16_unpack_canonical(b, status); 1782 FloatParts pr = div_floats(pa, pb, status); 1783 1784 return float16_round_pack_canonical(pr, status); 1785 } 1786 1787 static float32 QEMU_SOFTFLOAT_ATTR 1788 soft_f32_div(float32 a, float32 b, float_status *status) 1789 { 1790 FloatParts pa = float32_unpack_canonical(a, status); 1791 FloatParts pb = float32_unpack_canonical(b, status); 1792 FloatParts pr = div_floats(pa, pb, status); 1793 1794 return float32_round_pack_canonical(pr, status); 1795 } 1796 1797 static float64 QEMU_SOFTFLOAT_ATTR 1798 soft_f64_div(float64 a, float64 b, float_status *status) 1799 { 1800 FloatParts pa = float64_unpack_canonical(a, status); 1801 FloatParts pb = float64_unpack_canonical(b, status); 1802 FloatParts pr = div_floats(pa, pb, status); 1803 1804 return float64_round_pack_canonical(pr, status); 1805 } 1806 1807 static float hard_f32_div(float a, float b) 1808 { 1809 return a / b; 1810 } 1811 1812 static double hard_f64_div(double a, double b) 1813 { 1814 return a / b; 1815 } 1816 1817 static bool f32_div_pre(union_float32 a, union_float32 b) 1818 { 1819 if (QEMU_HARDFLOAT_2F32_USE_FP) { 1820 return (fpclassify(a.h) == FP_NORMAL || fpclassify(a.h) == FP_ZERO) && 1821 fpclassify(b.h) == FP_NORMAL; 1822 } 1823 return float32_is_zero_or_normal(a.s) && float32_is_normal(b.s); 1824 } 1825 1826 static bool f64_div_pre(union_float64 a, union_float64 b) 1827 { 1828 if (QEMU_HARDFLOAT_2F64_USE_FP) { 1829 return (fpclassify(a.h) == FP_NORMAL || fpclassify(a.h) == FP_ZERO) && 1830 fpclassify(b.h) == FP_NORMAL; 1831 } 1832 return float64_is_zero_or_normal(a.s) && float64_is_normal(b.s); 1833 } 1834 1835 static bool f32_div_post(union_float32 a, union_float32 b) 1836 { 1837 if (QEMU_HARDFLOAT_2F32_USE_FP) { 1838 return fpclassify(a.h) != FP_ZERO; 1839 } 1840 return !float32_is_zero(a.s); 1841 } 1842 1843 static bool f64_div_post(union_float64 a, union_float64 b) 1844 { 1845 if (QEMU_HARDFLOAT_2F64_USE_FP) { 1846 return fpclassify(a.h) != FP_ZERO; 1847 } 1848 return !float64_is_zero(a.s); 1849 } 1850 1851 float32 QEMU_FLATTEN 1852 float32_div(float32 a, float32 b, float_status *s) 1853 { 1854 return float32_gen2(a, b, s, hard_f32_div, soft_f32_div, 1855 f32_div_pre, f32_div_post, NULL, NULL); 1856 } 1857 1858 float64 QEMU_FLATTEN 1859 float64_div(float64 a, float64 b, float_status *s) 1860 { 1861 return float64_gen2(a, b, s, hard_f64_div, soft_f64_div, 1862 f64_div_pre, f64_div_post, NULL, NULL); 1863 } 1864 1865 /* 1866 * Float to Float conversions 1867 * 1868 * Returns the result of converting one float format to another. The 1869 * conversion is performed according to the IEC/IEEE Standard for 1870 * Binary Floating-Point Arithmetic. 1871 * 1872 * The float_to_float helper only needs to take care of raising 1873 * invalid exceptions and handling the conversion on NaNs. 1874 */ 1875 1876 static FloatParts float_to_float(FloatParts a, const FloatFmt *dstf, 1877 float_status *s) 1878 { 1879 if (dstf->arm_althp) { 1880 switch (a.cls) { 1881 case float_class_qnan: 1882 case float_class_snan: 1883 /* There is no NaN in the destination format. Raise Invalid 1884 * and return a zero with the sign of the input NaN. 1885 */ 1886 s->float_exception_flags |= float_flag_invalid; 1887 a.cls = float_class_zero; 1888 a.frac = 0; 1889 a.exp = 0; 1890 break; 1891 1892 case float_class_inf: 1893 /* There is no Inf in the destination format. Raise Invalid 1894 * and return the maximum normal with the correct sign. 1895 */ 1896 s->float_exception_flags |= float_flag_invalid; 1897 a.cls = float_class_normal; 1898 a.exp = dstf->exp_max; 1899 a.frac = ((1ull << dstf->frac_size) - 1) << dstf->frac_shift; 1900 break; 1901 1902 default: 1903 break; 1904 } 1905 } else if (is_nan(a.cls)) { 1906 if (is_snan(a.cls)) { 1907 s->float_exception_flags |= float_flag_invalid; 1908 a = parts_silence_nan(a, s); 1909 } 1910 if (s->default_nan_mode) { 1911 return parts_default_nan(s); 1912 } 1913 } 1914 return a; 1915 } 1916 1917 float32 float16_to_float32(float16 a, bool ieee, float_status *s) 1918 { 1919 const FloatFmt *fmt16 = ieee ? &float16_params : &float16_params_ahp; 1920 FloatParts p = float16a_unpack_canonical(a, s, fmt16); 1921 FloatParts pr = float_to_float(p, &float32_params, s); 1922 return float32_round_pack_canonical(pr, s); 1923 } 1924 1925 float64 float16_to_float64(float16 a, bool ieee, float_status *s) 1926 { 1927 const FloatFmt *fmt16 = ieee ? &float16_params : &float16_params_ahp; 1928 FloatParts p = float16a_unpack_canonical(a, s, fmt16); 1929 FloatParts pr = float_to_float(p, &float64_params, s); 1930 return float64_round_pack_canonical(pr, s); 1931 } 1932 1933 float16 float32_to_float16(float32 a, bool ieee, float_status *s) 1934 { 1935 const FloatFmt *fmt16 = ieee ? &float16_params : &float16_params_ahp; 1936 FloatParts p = float32_unpack_canonical(a, s); 1937 FloatParts pr = float_to_float(p, fmt16, s); 1938 return float16a_round_pack_canonical(pr, s, fmt16); 1939 } 1940 1941 float64 float32_to_float64(float32 a, float_status *s) 1942 { 1943 FloatParts p = float32_unpack_canonical(a, s); 1944 FloatParts pr = float_to_float(p, &float64_params, s); 1945 return float64_round_pack_canonical(pr, s); 1946 } 1947 1948 float16 float64_to_float16(float64 a, bool ieee, float_status *s) 1949 { 1950 const FloatFmt *fmt16 = ieee ? &float16_params : &float16_params_ahp; 1951 FloatParts p = float64_unpack_canonical(a, s); 1952 FloatParts pr = float_to_float(p, fmt16, s); 1953 return float16a_round_pack_canonical(pr, s, fmt16); 1954 } 1955 1956 float32 float64_to_float32(float64 a, float_status *s) 1957 { 1958 FloatParts p = float64_unpack_canonical(a, s); 1959 FloatParts pr = float_to_float(p, &float32_params, s); 1960 return float32_round_pack_canonical(pr, s); 1961 } 1962 1963 /* 1964 * Rounds the floating-point value `a' to an integer, and returns the 1965 * result as a floating-point value. The operation is performed 1966 * according to the IEC/IEEE Standard for Binary Floating-Point 1967 * Arithmetic. 1968 */ 1969 1970 static FloatParts round_to_int(FloatParts a, int rmode, 1971 int scale, float_status *s) 1972 { 1973 switch (a.cls) { 1974 case float_class_qnan: 1975 case float_class_snan: 1976 return return_nan(a, s); 1977 1978 case float_class_zero: 1979 case float_class_inf: 1980 /* already "integral" */ 1981 break; 1982 1983 case float_class_normal: 1984 scale = MIN(MAX(scale, -0x10000), 0x10000); 1985 a.exp += scale; 1986 1987 if (a.exp >= DECOMPOSED_BINARY_POINT) { 1988 /* already integral */ 1989 break; 1990 } 1991 if (a.exp < 0) { 1992 bool one; 1993 /* all fractional */ 1994 s->float_exception_flags |= float_flag_inexact; 1995 switch (rmode) { 1996 case float_round_nearest_even: 1997 one = a.exp == -1 && a.frac > DECOMPOSED_IMPLICIT_BIT; 1998 break; 1999 case float_round_ties_away: 2000 one = a.exp == -1 && a.frac >= DECOMPOSED_IMPLICIT_BIT; 2001 break; 2002 case float_round_to_zero: 2003 one = false; 2004 break; 2005 case float_round_up: 2006 one = !a.sign; 2007 break; 2008 case float_round_down: 2009 one = a.sign; 2010 break; 2011 case float_round_to_odd: 2012 one = true; 2013 break; 2014 default: 2015 g_assert_not_reached(); 2016 } 2017 2018 if (one) { 2019 a.frac = DECOMPOSED_IMPLICIT_BIT; 2020 a.exp = 0; 2021 } else { 2022 a.cls = float_class_zero; 2023 } 2024 } else { 2025 uint64_t frac_lsb = DECOMPOSED_IMPLICIT_BIT >> a.exp; 2026 uint64_t frac_lsbm1 = frac_lsb >> 1; 2027 uint64_t rnd_even_mask = (frac_lsb - 1) | frac_lsb; 2028 uint64_t rnd_mask = rnd_even_mask >> 1; 2029 uint64_t inc; 2030 2031 switch (rmode) { 2032 case float_round_nearest_even: 2033 inc = ((a.frac & rnd_even_mask) != frac_lsbm1 ? frac_lsbm1 : 0); 2034 break; 2035 case float_round_ties_away: 2036 inc = frac_lsbm1; 2037 break; 2038 case float_round_to_zero: 2039 inc = 0; 2040 break; 2041 case float_round_up: 2042 inc = a.sign ? 0 : rnd_mask; 2043 break; 2044 case float_round_down: 2045 inc = a.sign ? rnd_mask : 0; 2046 break; 2047 case float_round_to_odd: 2048 inc = a.frac & frac_lsb ? 0 : rnd_mask; 2049 break; 2050 default: 2051 g_assert_not_reached(); 2052 } 2053 2054 if (a.frac & rnd_mask) { 2055 s->float_exception_flags |= float_flag_inexact; 2056 a.frac += inc; 2057 a.frac &= ~rnd_mask; 2058 if (a.frac & DECOMPOSED_OVERFLOW_BIT) { 2059 a.frac >>= 1; 2060 a.exp++; 2061 } 2062 } 2063 } 2064 break; 2065 default: 2066 g_assert_not_reached(); 2067 } 2068 return a; 2069 } 2070 2071 float16 float16_round_to_int(float16 a, float_status *s) 2072 { 2073 FloatParts pa = float16_unpack_canonical(a, s); 2074 FloatParts pr = round_to_int(pa, s->float_rounding_mode, 0, s); 2075 return float16_round_pack_canonical(pr, s); 2076 } 2077 2078 float32 float32_round_to_int(float32 a, float_status *s) 2079 { 2080 FloatParts pa = float32_unpack_canonical(a, s); 2081 FloatParts pr = round_to_int(pa, s->float_rounding_mode, 0, s); 2082 return float32_round_pack_canonical(pr, s); 2083 } 2084 2085 float64 float64_round_to_int(float64 a, float_status *s) 2086 { 2087 FloatParts pa = float64_unpack_canonical(a, s); 2088 FloatParts pr = round_to_int(pa, s->float_rounding_mode, 0, s); 2089 return float64_round_pack_canonical(pr, s); 2090 } 2091 2092 /* 2093 * Returns the result of converting the floating-point value `a' to 2094 * the two's complement integer format. The conversion is performed 2095 * according to the IEC/IEEE Standard for Binary Floating-Point 2096 * Arithmetic---which means in particular that the conversion is 2097 * rounded according to the current rounding mode. If `a' is a NaN, 2098 * the largest positive integer is returned. Otherwise, if the 2099 * conversion overflows, the largest integer with the same sign as `a' 2100 * is returned. 2101 */ 2102 2103 static int64_t round_to_int_and_pack(FloatParts in, int rmode, int scale, 2104 int64_t min, int64_t max, 2105 float_status *s) 2106 { 2107 uint64_t r; 2108 int orig_flags = get_float_exception_flags(s); 2109 FloatParts p = round_to_int(in, rmode, scale, s); 2110 2111 switch (p.cls) { 2112 case float_class_snan: 2113 case float_class_qnan: 2114 s->float_exception_flags = orig_flags | float_flag_invalid; 2115 return max; 2116 case float_class_inf: 2117 s->float_exception_flags = orig_flags | float_flag_invalid; 2118 return p.sign ? min : max; 2119 case float_class_zero: 2120 return 0; 2121 case float_class_normal: 2122 if (p.exp < DECOMPOSED_BINARY_POINT) { 2123 r = p.frac >> (DECOMPOSED_BINARY_POINT - p.exp); 2124 } else if (p.exp - DECOMPOSED_BINARY_POINT < 2) { 2125 r = p.frac << (p.exp - DECOMPOSED_BINARY_POINT); 2126 } else { 2127 r = UINT64_MAX; 2128 } 2129 if (p.sign) { 2130 if (r <= -(uint64_t) min) { 2131 return -r; 2132 } else { 2133 s->float_exception_flags = orig_flags | float_flag_invalid; 2134 return min; 2135 } 2136 } else { 2137 if (r <= max) { 2138 return r; 2139 } else { 2140 s->float_exception_flags = orig_flags | float_flag_invalid; 2141 return max; 2142 } 2143 } 2144 default: 2145 g_assert_not_reached(); 2146 } 2147 } 2148 2149 int16_t float16_to_int16_scalbn(float16 a, int rmode, int scale, 2150 float_status *s) 2151 { 2152 return round_to_int_and_pack(float16_unpack_canonical(a, s), 2153 rmode, scale, INT16_MIN, INT16_MAX, s); 2154 } 2155 2156 int32_t float16_to_int32_scalbn(float16 a, int rmode, int scale, 2157 float_status *s) 2158 { 2159 return round_to_int_and_pack(float16_unpack_canonical(a, s), 2160 rmode, scale, INT32_MIN, INT32_MAX, s); 2161 } 2162 2163 int64_t float16_to_int64_scalbn(float16 a, int rmode, int scale, 2164 float_status *s) 2165 { 2166 return round_to_int_and_pack(float16_unpack_canonical(a, s), 2167 rmode, scale, INT64_MIN, INT64_MAX, s); 2168 } 2169 2170 int16_t float32_to_int16_scalbn(float32 a, int rmode, int scale, 2171 float_status *s) 2172 { 2173 return round_to_int_and_pack(float32_unpack_canonical(a, s), 2174 rmode, scale, INT16_MIN, INT16_MAX, s); 2175 } 2176 2177 int32_t float32_to_int32_scalbn(float32 a, int rmode, int scale, 2178 float_status *s) 2179 { 2180 return round_to_int_and_pack(float32_unpack_canonical(a, s), 2181 rmode, scale, INT32_MIN, INT32_MAX, s); 2182 } 2183 2184 int64_t float32_to_int64_scalbn(float32 a, int rmode, int scale, 2185 float_status *s) 2186 { 2187 return round_to_int_and_pack(float32_unpack_canonical(a, s), 2188 rmode, scale, INT64_MIN, INT64_MAX, s); 2189 } 2190 2191 int16_t float64_to_int16_scalbn(float64 a, int rmode, int scale, 2192 float_status *s) 2193 { 2194 return round_to_int_and_pack(float64_unpack_canonical(a, s), 2195 rmode, scale, INT16_MIN, INT16_MAX, s); 2196 } 2197 2198 int32_t float64_to_int32_scalbn(float64 a, int rmode, int scale, 2199 float_status *s) 2200 { 2201 return round_to_int_and_pack(float64_unpack_canonical(a, s), 2202 rmode, scale, INT32_MIN, INT32_MAX, s); 2203 } 2204 2205 int64_t float64_to_int64_scalbn(float64 a, int rmode, int scale, 2206 float_status *s) 2207 { 2208 return round_to_int_and_pack(float64_unpack_canonical(a, s), 2209 rmode, scale, INT64_MIN, INT64_MAX, s); 2210 } 2211 2212 int16_t float16_to_int16(float16 a, float_status *s) 2213 { 2214 return float16_to_int16_scalbn(a, s->float_rounding_mode, 0, s); 2215 } 2216 2217 int32_t float16_to_int32(float16 a, float_status *s) 2218 { 2219 return float16_to_int32_scalbn(a, s->float_rounding_mode, 0, s); 2220 } 2221 2222 int64_t float16_to_int64(float16 a, float_status *s) 2223 { 2224 return float16_to_int64_scalbn(a, s->float_rounding_mode, 0, s); 2225 } 2226 2227 int16_t float32_to_int16(float32 a, float_status *s) 2228 { 2229 return float32_to_int16_scalbn(a, s->float_rounding_mode, 0, s); 2230 } 2231 2232 int32_t float32_to_int32(float32 a, float_status *s) 2233 { 2234 return float32_to_int32_scalbn(a, s->float_rounding_mode, 0, s); 2235 } 2236 2237 int64_t float32_to_int64(float32 a, float_status *s) 2238 { 2239 return float32_to_int64_scalbn(a, s->float_rounding_mode, 0, s); 2240 } 2241 2242 int16_t float64_to_int16(float64 a, float_status *s) 2243 { 2244 return float64_to_int16_scalbn(a, s->float_rounding_mode, 0, s); 2245 } 2246 2247 int32_t float64_to_int32(float64 a, float_status *s) 2248 { 2249 return float64_to_int32_scalbn(a, s->float_rounding_mode, 0, s); 2250 } 2251 2252 int64_t float64_to_int64(float64 a, float_status *s) 2253 { 2254 return float64_to_int64_scalbn(a, s->float_rounding_mode, 0, s); 2255 } 2256 2257 int16_t float16_to_int16_round_to_zero(float16 a, float_status *s) 2258 { 2259 return float16_to_int16_scalbn(a, float_round_to_zero, 0, s); 2260 } 2261 2262 int32_t float16_to_int32_round_to_zero(float16 a, float_status *s) 2263 { 2264 return float16_to_int32_scalbn(a, float_round_to_zero, 0, s); 2265 } 2266 2267 int64_t float16_to_int64_round_to_zero(float16 a, float_status *s) 2268 { 2269 return float16_to_int64_scalbn(a, float_round_to_zero, 0, s); 2270 } 2271 2272 int16_t float32_to_int16_round_to_zero(float32 a, float_status *s) 2273 { 2274 return float32_to_int16_scalbn(a, float_round_to_zero, 0, s); 2275 } 2276 2277 int32_t float32_to_int32_round_to_zero(float32 a, float_status *s) 2278 { 2279 return float32_to_int32_scalbn(a, float_round_to_zero, 0, s); 2280 } 2281 2282 int64_t float32_to_int64_round_to_zero(float32 a, float_status *s) 2283 { 2284 return float32_to_int64_scalbn(a, float_round_to_zero, 0, s); 2285 } 2286 2287 int16_t float64_to_int16_round_to_zero(float64 a, float_status *s) 2288 { 2289 return float64_to_int16_scalbn(a, float_round_to_zero, 0, s); 2290 } 2291 2292 int32_t float64_to_int32_round_to_zero(float64 a, float_status *s) 2293 { 2294 return float64_to_int32_scalbn(a, float_round_to_zero, 0, s); 2295 } 2296 2297 int64_t float64_to_int64_round_to_zero(float64 a, float_status *s) 2298 { 2299 return float64_to_int64_scalbn(a, float_round_to_zero, 0, s); 2300 } 2301 2302 /* 2303 * Returns the result of converting the floating-point value `a' to 2304 * the unsigned integer format. The conversion is performed according 2305 * to the IEC/IEEE Standard for Binary Floating-Point 2306 * Arithmetic---which means in particular that the conversion is 2307 * rounded according to the current rounding mode. If `a' is a NaN, 2308 * the largest unsigned integer is returned. Otherwise, if the 2309 * conversion overflows, the largest unsigned integer is returned. If 2310 * the 'a' is negative, the result is rounded and zero is returned; 2311 * values that do not round to zero will raise the inexact exception 2312 * flag. 2313 */ 2314 2315 static uint64_t round_to_uint_and_pack(FloatParts in, int rmode, int scale, 2316 uint64_t max, float_status *s) 2317 { 2318 int orig_flags = get_float_exception_flags(s); 2319 FloatParts p = round_to_int(in, rmode, scale, s); 2320 uint64_t r; 2321 2322 switch (p.cls) { 2323 case float_class_snan: 2324 case float_class_qnan: 2325 s->float_exception_flags = orig_flags | float_flag_invalid; 2326 return max; 2327 case float_class_inf: 2328 s->float_exception_flags = orig_flags | float_flag_invalid; 2329 return p.sign ? 0 : max; 2330 case float_class_zero: 2331 return 0; 2332 case float_class_normal: 2333 if (p.sign) { 2334 s->float_exception_flags = orig_flags | float_flag_invalid; 2335 return 0; 2336 } 2337 2338 if (p.exp < DECOMPOSED_BINARY_POINT) { 2339 r = p.frac >> (DECOMPOSED_BINARY_POINT - p.exp); 2340 } else if (p.exp - DECOMPOSED_BINARY_POINT < 2) { 2341 r = p.frac << (p.exp - DECOMPOSED_BINARY_POINT); 2342 } else { 2343 s->float_exception_flags = orig_flags | float_flag_invalid; 2344 return max; 2345 } 2346 2347 /* For uint64 this will never trip, but if p.exp is too large 2348 * to shift a decomposed fraction we shall have exited via the 2349 * 3rd leg above. 2350 */ 2351 if (r > max) { 2352 s->float_exception_flags = orig_flags | float_flag_invalid; 2353 return max; 2354 } 2355 return r; 2356 default: 2357 g_assert_not_reached(); 2358 } 2359 } 2360 2361 uint16_t float16_to_uint16_scalbn(float16 a, int rmode, int scale, 2362 float_status *s) 2363 { 2364 return round_to_uint_and_pack(float16_unpack_canonical(a, s), 2365 rmode, scale, UINT16_MAX, s); 2366 } 2367 2368 uint32_t float16_to_uint32_scalbn(float16 a, int rmode, int scale, 2369 float_status *s) 2370 { 2371 return round_to_uint_and_pack(float16_unpack_canonical(a, s), 2372 rmode, scale, UINT32_MAX, s); 2373 } 2374 2375 uint64_t float16_to_uint64_scalbn(float16 a, int rmode, int scale, 2376 float_status *s) 2377 { 2378 return round_to_uint_and_pack(float16_unpack_canonical(a, s), 2379 rmode, scale, UINT64_MAX, s); 2380 } 2381 2382 uint16_t float32_to_uint16_scalbn(float32 a, int rmode, int scale, 2383 float_status *s) 2384 { 2385 return round_to_uint_and_pack(float32_unpack_canonical(a, s), 2386 rmode, scale, UINT16_MAX, s); 2387 } 2388 2389 uint32_t float32_to_uint32_scalbn(float32 a, int rmode, int scale, 2390 float_status *s) 2391 { 2392 return round_to_uint_and_pack(float32_unpack_canonical(a, s), 2393 rmode, scale, UINT32_MAX, s); 2394 } 2395 2396 uint64_t float32_to_uint64_scalbn(float32 a, int rmode, int scale, 2397 float_status *s) 2398 { 2399 return round_to_uint_and_pack(float32_unpack_canonical(a, s), 2400 rmode, scale, UINT64_MAX, s); 2401 } 2402 2403 uint16_t float64_to_uint16_scalbn(float64 a, int rmode, int scale, 2404 float_status *s) 2405 { 2406 return round_to_uint_and_pack(float64_unpack_canonical(a, s), 2407 rmode, scale, UINT16_MAX, s); 2408 } 2409 2410 uint32_t float64_to_uint32_scalbn(float64 a, int rmode, int scale, 2411 float_status *s) 2412 { 2413 return round_to_uint_and_pack(float64_unpack_canonical(a, s), 2414 rmode, scale, UINT32_MAX, s); 2415 } 2416 2417 uint64_t float64_to_uint64_scalbn(float64 a, int rmode, int scale, 2418 float_status *s) 2419 { 2420 return round_to_uint_and_pack(float64_unpack_canonical(a, s), 2421 rmode, scale, UINT64_MAX, s); 2422 } 2423 2424 uint16_t float16_to_uint16(float16 a, float_status *s) 2425 { 2426 return float16_to_uint16_scalbn(a, s->float_rounding_mode, 0, s); 2427 } 2428 2429 uint32_t float16_to_uint32(float16 a, float_status *s) 2430 { 2431 return float16_to_uint32_scalbn(a, s->float_rounding_mode, 0, s); 2432 } 2433 2434 uint64_t float16_to_uint64(float16 a, float_status *s) 2435 { 2436 return float16_to_uint64_scalbn(a, s->float_rounding_mode, 0, s); 2437 } 2438 2439 uint16_t float32_to_uint16(float32 a, float_status *s) 2440 { 2441 return float32_to_uint16_scalbn(a, s->float_rounding_mode, 0, s); 2442 } 2443 2444 uint32_t float32_to_uint32(float32 a, float_status *s) 2445 { 2446 return float32_to_uint32_scalbn(a, s->float_rounding_mode, 0, s); 2447 } 2448 2449 uint64_t float32_to_uint64(float32 a, float_status *s) 2450 { 2451 return float32_to_uint64_scalbn(a, s->float_rounding_mode, 0, s); 2452 } 2453 2454 uint16_t float64_to_uint16(float64 a, float_status *s) 2455 { 2456 return float64_to_uint16_scalbn(a, s->float_rounding_mode, 0, s); 2457 } 2458 2459 uint32_t float64_to_uint32(float64 a, float_status *s) 2460 { 2461 return float64_to_uint32_scalbn(a, s->float_rounding_mode, 0, s); 2462 } 2463 2464 uint64_t float64_to_uint64(float64 a, float_status *s) 2465 { 2466 return float64_to_uint64_scalbn(a, s->float_rounding_mode, 0, s); 2467 } 2468 2469 uint16_t float16_to_uint16_round_to_zero(float16 a, float_status *s) 2470 { 2471 return float16_to_uint16_scalbn(a, float_round_to_zero, 0, s); 2472 } 2473 2474 uint32_t float16_to_uint32_round_to_zero(float16 a, float_status *s) 2475 { 2476 return float16_to_uint32_scalbn(a, float_round_to_zero, 0, s); 2477 } 2478 2479 uint64_t float16_to_uint64_round_to_zero(float16 a, float_status *s) 2480 { 2481 return float16_to_uint64_scalbn(a, float_round_to_zero, 0, s); 2482 } 2483 2484 uint16_t float32_to_uint16_round_to_zero(float32 a, float_status *s) 2485 { 2486 return float32_to_uint16_scalbn(a, float_round_to_zero, 0, s); 2487 } 2488 2489 uint32_t float32_to_uint32_round_to_zero(float32 a, float_status *s) 2490 { 2491 return float32_to_uint32_scalbn(a, float_round_to_zero, 0, s); 2492 } 2493 2494 uint64_t float32_to_uint64_round_to_zero(float32 a, float_status *s) 2495 { 2496 return float32_to_uint64_scalbn(a, float_round_to_zero, 0, s); 2497 } 2498 2499 uint16_t float64_to_uint16_round_to_zero(float64 a, float_status *s) 2500 { 2501 return float64_to_uint16_scalbn(a, float_round_to_zero, 0, s); 2502 } 2503 2504 uint32_t float64_to_uint32_round_to_zero(float64 a, float_status *s) 2505 { 2506 return float64_to_uint32_scalbn(a, float_round_to_zero, 0, s); 2507 } 2508 2509 uint64_t float64_to_uint64_round_to_zero(float64 a, float_status *s) 2510 { 2511 return float64_to_uint64_scalbn(a, float_round_to_zero, 0, s); 2512 } 2513 2514 /* 2515 * Integer to float conversions 2516 * 2517 * Returns the result of converting the two's complement integer `a' 2518 * to the floating-point format. The conversion is performed according 2519 * to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 2520 */ 2521 2522 static FloatParts int_to_float(int64_t a, int scale, float_status *status) 2523 { 2524 FloatParts r = { .sign = false }; 2525 2526 if (a == 0) { 2527 r.cls = float_class_zero; 2528 } else { 2529 uint64_t f = a; 2530 int shift; 2531 2532 r.cls = float_class_normal; 2533 if (a < 0) { 2534 f = -f; 2535 r.sign = true; 2536 } 2537 shift = clz64(f) - 1; 2538 scale = MIN(MAX(scale, -0x10000), 0x10000); 2539 2540 r.exp = DECOMPOSED_BINARY_POINT - shift + scale; 2541 r.frac = (shift < 0 ? DECOMPOSED_IMPLICIT_BIT : f << shift); 2542 } 2543 2544 return r; 2545 } 2546 2547 float16 int64_to_float16_scalbn(int64_t a, int scale, float_status *status) 2548 { 2549 FloatParts pa = int_to_float(a, scale, status); 2550 return float16_round_pack_canonical(pa, status); 2551 } 2552 2553 float16 int32_to_float16_scalbn(int32_t a, int scale, float_status *status) 2554 { 2555 return int64_to_float16_scalbn(a, scale, status); 2556 } 2557 2558 float16 int16_to_float16_scalbn(int16_t a, int scale, float_status *status) 2559 { 2560 return int64_to_float16_scalbn(a, scale, status); 2561 } 2562 2563 float16 int64_to_float16(int64_t a, float_status *status) 2564 { 2565 return int64_to_float16_scalbn(a, 0, status); 2566 } 2567 2568 float16 int32_to_float16(int32_t a, float_status *status) 2569 { 2570 return int64_to_float16_scalbn(a, 0, status); 2571 } 2572 2573 float16 int16_to_float16(int16_t a, float_status *status) 2574 { 2575 return int64_to_float16_scalbn(a, 0, status); 2576 } 2577 2578 float32 int64_to_float32_scalbn(int64_t a, int scale, float_status *status) 2579 { 2580 FloatParts pa = int_to_float(a, scale, status); 2581 return float32_round_pack_canonical(pa, status); 2582 } 2583 2584 float32 int32_to_float32_scalbn(int32_t a, int scale, float_status *status) 2585 { 2586 return int64_to_float32_scalbn(a, scale, status); 2587 } 2588 2589 float32 int16_to_float32_scalbn(int16_t a, int scale, float_status *status) 2590 { 2591 return int64_to_float32_scalbn(a, scale, status); 2592 } 2593 2594 float32 int64_to_float32(int64_t a, float_status *status) 2595 { 2596 return int64_to_float32_scalbn(a, 0, status); 2597 } 2598 2599 float32 int32_to_float32(int32_t a, float_status *status) 2600 { 2601 return int64_to_float32_scalbn(a, 0, status); 2602 } 2603 2604 float32 int16_to_float32(int16_t a, float_status *status) 2605 { 2606 return int64_to_float32_scalbn(a, 0, status); 2607 } 2608 2609 float64 int64_to_float64_scalbn(int64_t a, int scale, float_status *status) 2610 { 2611 FloatParts pa = int_to_float(a, scale, status); 2612 return float64_round_pack_canonical(pa, status); 2613 } 2614 2615 float64 int32_to_float64_scalbn(int32_t a, int scale, float_status *status) 2616 { 2617 return int64_to_float64_scalbn(a, scale, status); 2618 } 2619 2620 float64 int16_to_float64_scalbn(int16_t a, int scale, float_status *status) 2621 { 2622 return int64_to_float64_scalbn(a, scale, status); 2623 } 2624 2625 float64 int64_to_float64(int64_t a, float_status *status) 2626 { 2627 return int64_to_float64_scalbn(a, 0, status); 2628 } 2629 2630 float64 int32_to_float64(int32_t a, float_status *status) 2631 { 2632 return int64_to_float64_scalbn(a, 0, status); 2633 } 2634 2635 float64 int16_to_float64(int16_t a, float_status *status) 2636 { 2637 return int64_to_float64_scalbn(a, 0, status); 2638 } 2639 2640 2641 /* 2642 * Unsigned Integer to float conversions 2643 * 2644 * Returns the result of converting the unsigned integer `a' to the 2645 * floating-point format. The conversion is performed according to the 2646 * IEC/IEEE Standard for Binary Floating-Point Arithmetic. 2647 */ 2648 2649 static FloatParts uint_to_float(uint64_t a, int scale, float_status *status) 2650 { 2651 FloatParts r = { .sign = false }; 2652 2653 if (a == 0) { 2654 r.cls = float_class_zero; 2655 } else { 2656 scale = MIN(MAX(scale, -0x10000), 0x10000); 2657 r.cls = float_class_normal; 2658 if ((int64_t)a < 0) { 2659 r.exp = DECOMPOSED_BINARY_POINT + 1 + scale; 2660 shift64RightJamming(a, 1, &a); 2661 r.frac = a; 2662 } else { 2663 int shift = clz64(a) - 1; 2664 r.exp = DECOMPOSED_BINARY_POINT - shift + scale; 2665 r.frac = a << shift; 2666 } 2667 } 2668 2669 return r; 2670 } 2671 2672 float16 uint64_to_float16_scalbn(uint64_t a, int scale, float_status *status) 2673 { 2674 FloatParts pa = uint_to_float(a, scale, status); 2675 return float16_round_pack_canonical(pa, status); 2676 } 2677 2678 float16 uint32_to_float16_scalbn(uint32_t a, int scale, float_status *status) 2679 { 2680 return uint64_to_float16_scalbn(a, scale, status); 2681 } 2682 2683 float16 uint16_to_float16_scalbn(uint16_t a, int scale, float_status *status) 2684 { 2685 return uint64_to_float16_scalbn(a, scale, status); 2686 } 2687 2688 float16 uint64_to_float16(uint64_t a, float_status *status) 2689 { 2690 return uint64_to_float16_scalbn(a, 0, status); 2691 } 2692 2693 float16 uint32_to_float16(uint32_t a, float_status *status) 2694 { 2695 return uint64_to_float16_scalbn(a, 0, status); 2696 } 2697 2698 float16 uint16_to_float16(uint16_t a, float_status *status) 2699 { 2700 return uint64_to_float16_scalbn(a, 0, status); 2701 } 2702 2703 float32 uint64_to_float32_scalbn(uint64_t a, int scale, float_status *status) 2704 { 2705 FloatParts pa = uint_to_float(a, scale, status); 2706 return float32_round_pack_canonical(pa, status); 2707 } 2708 2709 float32 uint32_to_float32_scalbn(uint32_t a, int scale, float_status *status) 2710 { 2711 return uint64_to_float32_scalbn(a, scale, status); 2712 } 2713 2714 float32 uint16_to_float32_scalbn(uint16_t a, int scale, float_status *status) 2715 { 2716 return uint64_to_float32_scalbn(a, scale, status); 2717 } 2718 2719 float32 uint64_to_float32(uint64_t a, float_status *status) 2720 { 2721 return uint64_to_float32_scalbn(a, 0, status); 2722 } 2723 2724 float32 uint32_to_float32(uint32_t a, float_status *status) 2725 { 2726 return uint64_to_float32_scalbn(a, 0, status); 2727 } 2728 2729 float32 uint16_to_float32(uint16_t a, float_status *status) 2730 { 2731 return uint64_to_float32_scalbn(a, 0, status); 2732 } 2733 2734 float64 uint64_to_float64_scalbn(uint64_t a, int scale, float_status *status) 2735 { 2736 FloatParts pa = uint_to_float(a, scale, status); 2737 return float64_round_pack_canonical(pa, status); 2738 } 2739 2740 float64 uint32_to_float64_scalbn(uint32_t a, int scale, float_status *status) 2741 { 2742 return uint64_to_float64_scalbn(a, scale, status); 2743 } 2744 2745 float64 uint16_to_float64_scalbn(uint16_t a, int scale, float_status *status) 2746 { 2747 return uint64_to_float64_scalbn(a, scale, status); 2748 } 2749 2750 float64 uint64_to_float64(uint64_t a, float_status *status) 2751 { 2752 return uint64_to_float64_scalbn(a, 0, status); 2753 } 2754 2755 float64 uint32_to_float64(uint32_t a, float_status *status) 2756 { 2757 return uint64_to_float64_scalbn(a, 0, status); 2758 } 2759 2760 float64 uint16_to_float64(uint16_t a, float_status *status) 2761 { 2762 return uint64_to_float64_scalbn(a, 0, status); 2763 } 2764 2765 /* Float Min/Max */ 2766 /* min() and max() functions. These can't be implemented as 2767 * 'compare and pick one input' because that would mishandle 2768 * NaNs and +0 vs -0. 2769 * 2770 * minnum() and maxnum() functions. These are similar to the min() 2771 * and max() functions but if one of the arguments is a QNaN and 2772 * the other is numerical then the numerical argument is returned. 2773 * SNaNs will get quietened before being returned. 2774 * minnum() and maxnum correspond to the IEEE 754-2008 minNum() 2775 * and maxNum() operations. min() and max() are the typical min/max 2776 * semantics provided by many CPUs which predate that specification. 2777 * 2778 * minnummag() and maxnummag() functions correspond to minNumMag() 2779 * and minNumMag() from the IEEE-754 2008. 2780 */ 2781 static FloatParts minmax_floats(FloatParts a, FloatParts b, bool ismin, 2782 bool ieee, bool ismag, float_status *s) 2783 { 2784 if (unlikely(is_nan(a.cls) || is_nan(b.cls))) { 2785 if (ieee) { 2786 /* Takes two floating-point values `a' and `b', one of 2787 * which is a NaN, and returns the appropriate NaN 2788 * result. If either `a' or `b' is a signaling NaN, 2789 * the invalid exception is raised. 2790 */ 2791 if (is_snan(a.cls) || is_snan(b.cls)) { 2792 return pick_nan(a, b, s); 2793 } else if (is_nan(a.cls) && !is_nan(b.cls)) { 2794 return b; 2795 } else if (is_nan(b.cls) && !is_nan(a.cls)) { 2796 return a; 2797 } 2798 } 2799 return pick_nan(a, b, s); 2800 } else { 2801 int a_exp, b_exp; 2802 2803 switch (a.cls) { 2804 case float_class_normal: 2805 a_exp = a.exp; 2806 break; 2807 case float_class_inf: 2808 a_exp = INT_MAX; 2809 break; 2810 case float_class_zero: 2811 a_exp = INT_MIN; 2812 break; 2813 default: 2814 g_assert_not_reached(); 2815 break; 2816 } 2817 switch (b.cls) { 2818 case float_class_normal: 2819 b_exp = b.exp; 2820 break; 2821 case float_class_inf: 2822 b_exp = INT_MAX; 2823 break; 2824 case float_class_zero: 2825 b_exp = INT_MIN; 2826 break; 2827 default: 2828 g_assert_not_reached(); 2829 break; 2830 } 2831 2832 if (ismag && (a_exp != b_exp || a.frac != b.frac)) { 2833 bool a_less = a_exp < b_exp; 2834 if (a_exp == b_exp) { 2835 a_less = a.frac < b.frac; 2836 } 2837 return a_less ^ ismin ? b : a; 2838 } 2839 2840 if (a.sign == b.sign) { 2841 bool a_less = a_exp < b_exp; 2842 if (a_exp == b_exp) { 2843 a_less = a.frac < b.frac; 2844 } 2845 return a.sign ^ a_less ^ ismin ? b : a; 2846 } else { 2847 return a.sign ^ ismin ? b : a; 2848 } 2849 } 2850 } 2851 2852 #define MINMAX(sz, name, ismin, isiee, ismag) \ 2853 float ## sz float ## sz ## _ ## name(float ## sz a, float ## sz b, \ 2854 float_status *s) \ 2855 { \ 2856 FloatParts pa = float ## sz ## _unpack_canonical(a, s); \ 2857 FloatParts pb = float ## sz ## _unpack_canonical(b, s); \ 2858 FloatParts pr = minmax_floats(pa, pb, ismin, isiee, ismag, s); \ 2859 \ 2860 return float ## sz ## _round_pack_canonical(pr, s); \ 2861 } 2862 2863 MINMAX(16, min, true, false, false) 2864 MINMAX(16, minnum, true, true, false) 2865 MINMAX(16, minnummag, true, true, true) 2866 MINMAX(16, max, false, false, false) 2867 MINMAX(16, maxnum, false, true, false) 2868 MINMAX(16, maxnummag, false, true, true) 2869 2870 MINMAX(32, min, true, false, false) 2871 MINMAX(32, minnum, true, true, false) 2872 MINMAX(32, minnummag, true, true, true) 2873 MINMAX(32, max, false, false, false) 2874 MINMAX(32, maxnum, false, true, false) 2875 MINMAX(32, maxnummag, false, true, true) 2876 2877 MINMAX(64, min, true, false, false) 2878 MINMAX(64, minnum, true, true, false) 2879 MINMAX(64, minnummag, true, true, true) 2880 MINMAX(64, max, false, false, false) 2881 MINMAX(64, maxnum, false, true, false) 2882 MINMAX(64, maxnummag, false, true, true) 2883 2884 #undef MINMAX 2885 2886 /* Floating point compare */ 2887 static int compare_floats(FloatParts a, FloatParts b, bool is_quiet, 2888 float_status *s) 2889 { 2890 if (is_nan(a.cls) || is_nan(b.cls)) { 2891 if (!is_quiet || 2892 a.cls == float_class_snan || 2893 b.cls == float_class_snan) { 2894 s->float_exception_flags |= float_flag_invalid; 2895 } 2896 return float_relation_unordered; 2897 } 2898 2899 if (a.cls == float_class_zero) { 2900 if (b.cls == float_class_zero) { 2901 return float_relation_equal; 2902 } 2903 return b.sign ? float_relation_greater : float_relation_less; 2904 } else if (b.cls == float_class_zero) { 2905 return a.sign ? float_relation_less : float_relation_greater; 2906 } 2907 2908 /* The only really important thing about infinity is its sign. If 2909 * both are infinities the sign marks the smallest of the two. 2910 */ 2911 if (a.cls == float_class_inf) { 2912 if ((b.cls == float_class_inf) && (a.sign == b.sign)) { 2913 return float_relation_equal; 2914 } 2915 return a.sign ? float_relation_less : float_relation_greater; 2916 } else if (b.cls == float_class_inf) { 2917 return b.sign ? float_relation_greater : float_relation_less; 2918 } 2919 2920 if (a.sign != b.sign) { 2921 return a.sign ? float_relation_less : float_relation_greater; 2922 } 2923 2924 if (a.exp == b.exp) { 2925 if (a.frac == b.frac) { 2926 return float_relation_equal; 2927 } 2928 if (a.sign) { 2929 return a.frac > b.frac ? 2930 float_relation_less : float_relation_greater; 2931 } else { 2932 return a.frac > b.frac ? 2933 float_relation_greater : float_relation_less; 2934 } 2935 } else { 2936 if (a.sign) { 2937 return a.exp > b.exp ? float_relation_less : float_relation_greater; 2938 } else { 2939 return a.exp > b.exp ? float_relation_greater : float_relation_less; 2940 } 2941 } 2942 } 2943 2944 #define COMPARE(name, attr, sz) \ 2945 static int attr \ 2946 name(float ## sz a, float ## sz b, bool is_quiet, float_status *s) \ 2947 { \ 2948 FloatParts pa = float ## sz ## _unpack_canonical(a, s); \ 2949 FloatParts pb = float ## sz ## _unpack_canonical(b, s); \ 2950 return compare_floats(pa, pb, is_quiet, s); \ 2951 } 2952 2953 COMPARE(soft_f16_compare, QEMU_FLATTEN, 16) 2954 COMPARE(soft_f32_compare, QEMU_SOFTFLOAT_ATTR, 32) 2955 COMPARE(soft_f64_compare, QEMU_SOFTFLOAT_ATTR, 64) 2956 2957 #undef COMPARE 2958 2959 int float16_compare(float16 a, float16 b, float_status *s) 2960 { 2961 return soft_f16_compare(a, b, false, s); 2962 } 2963 2964 int float16_compare_quiet(float16 a, float16 b, float_status *s) 2965 { 2966 return soft_f16_compare(a, b, true, s); 2967 } 2968 2969 static int QEMU_FLATTEN 2970 f32_compare(float32 xa, float32 xb, bool is_quiet, float_status *s) 2971 { 2972 union_float32 ua, ub; 2973 2974 ua.s = xa; 2975 ub.s = xb; 2976 2977 if (QEMU_NO_HARDFLOAT) { 2978 goto soft; 2979 } 2980 2981 float32_input_flush2(&ua.s, &ub.s, s); 2982 if (isgreaterequal(ua.h, ub.h)) { 2983 if (isgreater(ua.h, ub.h)) { 2984 return float_relation_greater; 2985 } 2986 return float_relation_equal; 2987 } 2988 if (likely(isless(ua.h, ub.h))) { 2989 return float_relation_less; 2990 } 2991 /* The only condition remaining is unordered. 2992 * Fall through to set flags. 2993 */ 2994 soft: 2995 return soft_f32_compare(ua.s, ub.s, is_quiet, s); 2996 } 2997 2998 int float32_compare(float32 a, float32 b, float_status *s) 2999 { 3000 return f32_compare(a, b, false, s); 3001 } 3002 3003 int float32_compare_quiet(float32 a, float32 b, float_status *s) 3004 { 3005 return f32_compare(a, b, true, s); 3006 } 3007 3008 static int QEMU_FLATTEN 3009 f64_compare(float64 xa, float64 xb, bool is_quiet, float_status *s) 3010 { 3011 union_float64 ua, ub; 3012 3013 ua.s = xa; 3014 ub.s = xb; 3015 3016 if (QEMU_NO_HARDFLOAT) { 3017 goto soft; 3018 } 3019 3020 float64_input_flush2(&ua.s, &ub.s, s); 3021 if (isgreaterequal(ua.h, ub.h)) { 3022 if (isgreater(ua.h, ub.h)) { 3023 return float_relation_greater; 3024 } 3025 return float_relation_equal; 3026 } 3027 if (likely(isless(ua.h, ub.h))) { 3028 return float_relation_less; 3029 } 3030 /* The only condition remaining is unordered. 3031 * Fall through to set flags. 3032 */ 3033 soft: 3034 return soft_f64_compare(ua.s, ub.s, is_quiet, s); 3035 } 3036 3037 int float64_compare(float64 a, float64 b, float_status *s) 3038 { 3039 return f64_compare(a, b, false, s); 3040 } 3041 3042 int float64_compare_quiet(float64 a, float64 b, float_status *s) 3043 { 3044 return f64_compare(a, b, true, s); 3045 } 3046 3047 /* Multiply A by 2 raised to the power N. */ 3048 static FloatParts scalbn_decomposed(FloatParts a, int n, float_status *s) 3049 { 3050 if (unlikely(is_nan(a.cls))) { 3051 return return_nan(a, s); 3052 } 3053 if (a.cls == float_class_normal) { 3054 /* The largest float type (even though not supported by FloatParts) 3055 * is float128, which has a 15 bit exponent. Bounding N to 16 bits 3056 * still allows rounding to infinity, without allowing overflow 3057 * within the int32_t that backs FloatParts.exp. 3058 */ 3059 n = MIN(MAX(n, -0x10000), 0x10000); 3060 a.exp += n; 3061 } 3062 return a; 3063 } 3064 3065 float16 float16_scalbn(float16 a, int n, float_status *status) 3066 { 3067 FloatParts pa = float16_unpack_canonical(a, status); 3068 FloatParts pr = scalbn_decomposed(pa, n, status); 3069 return float16_round_pack_canonical(pr, status); 3070 } 3071 3072 float32 float32_scalbn(float32 a, int n, float_status *status) 3073 { 3074 FloatParts pa = float32_unpack_canonical(a, status); 3075 FloatParts pr = scalbn_decomposed(pa, n, status); 3076 return float32_round_pack_canonical(pr, status); 3077 } 3078 3079 float64 float64_scalbn(float64 a, int n, float_status *status) 3080 { 3081 FloatParts pa = float64_unpack_canonical(a, status); 3082 FloatParts pr = scalbn_decomposed(pa, n, status); 3083 return float64_round_pack_canonical(pr, status); 3084 } 3085 3086 /* 3087 * Square Root 3088 * 3089 * The old softfloat code did an approximation step before zeroing in 3090 * on the final result. However for simpleness we just compute the 3091 * square root by iterating down from the implicit bit to enough extra 3092 * bits to ensure we get a correctly rounded result. 3093 * 3094 * This does mean however the calculation is slower than before, 3095 * especially for 64 bit floats. 3096 */ 3097 3098 static FloatParts sqrt_float(FloatParts a, float_status *s, const FloatFmt *p) 3099 { 3100 uint64_t a_frac, r_frac, s_frac; 3101 int bit, last_bit; 3102 3103 if (is_nan(a.cls)) { 3104 return return_nan(a, s); 3105 } 3106 if (a.cls == float_class_zero) { 3107 return a; /* sqrt(+-0) = +-0 */ 3108 } 3109 if (a.sign) { 3110 s->float_exception_flags |= float_flag_invalid; 3111 return parts_default_nan(s); 3112 } 3113 if (a.cls == float_class_inf) { 3114 return a; /* sqrt(+inf) = +inf */ 3115 } 3116 3117 assert(a.cls == float_class_normal); 3118 3119 /* We need two overflow bits at the top. Adding room for that is a 3120 * right shift. If the exponent is odd, we can discard the low bit 3121 * by multiplying the fraction by 2; that's a left shift. Combine 3122 * those and we shift right if the exponent is even. 3123 */ 3124 a_frac = a.frac; 3125 if (!(a.exp & 1)) { 3126 a_frac >>= 1; 3127 } 3128 a.exp >>= 1; 3129 3130 /* Bit-by-bit computation of sqrt. */ 3131 r_frac = 0; 3132 s_frac = 0; 3133 3134 /* Iterate from implicit bit down to the 3 extra bits to compute a 3135 * properly rounded result. Remember we've inserted one more bit 3136 * at the top, so these positions are one less. 3137 */ 3138 bit = DECOMPOSED_BINARY_POINT - 1; 3139 last_bit = MAX(p->frac_shift - 4, 0); 3140 do { 3141 uint64_t q = 1ULL << bit; 3142 uint64_t t_frac = s_frac + q; 3143 if (t_frac <= a_frac) { 3144 s_frac = t_frac + q; 3145 a_frac -= t_frac; 3146 r_frac += q; 3147 } 3148 a_frac <<= 1; 3149 } while (--bit >= last_bit); 3150 3151 /* Undo the right shift done above. If there is any remaining 3152 * fraction, the result is inexact. Set the sticky bit. 3153 */ 3154 a.frac = (r_frac << 1) + (a_frac != 0); 3155 3156 return a; 3157 } 3158 3159 float16 QEMU_FLATTEN float16_sqrt(float16 a, float_status *status) 3160 { 3161 FloatParts pa = float16_unpack_canonical(a, status); 3162 FloatParts pr = sqrt_float(pa, status, &float16_params); 3163 return float16_round_pack_canonical(pr, status); 3164 } 3165 3166 static float32 QEMU_SOFTFLOAT_ATTR 3167 soft_f32_sqrt(float32 a, float_status *status) 3168 { 3169 FloatParts pa = float32_unpack_canonical(a, status); 3170 FloatParts pr = sqrt_float(pa, status, &float32_params); 3171 return float32_round_pack_canonical(pr, status); 3172 } 3173 3174 static float64 QEMU_SOFTFLOAT_ATTR 3175 soft_f64_sqrt(float64 a, float_status *status) 3176 { 3177 FloatParts pa = float64_unpack_canonical(a, status); 3178 FloatParts pr = sqrt_float(pa, status, &float64_params); 3179 return float64_round_pack_canonical(pr, status); 3180 } 3181 3182 float32 QEMU_FLATTEN float32_sqrt(float32 xa, float_status *s) 3183 { 3184 union_float32 ua, ur; 3185 3186 ua.s = xa; 3187 if (unlikely(!can_use_fpu(s))) { 3188 goto soft; 3189 } 3190 3191 float32_input_flush1(&ua.s, s); 3192 if (QEMU_HARDFLOAT_1F32_USE_FP) { 3193 if (unlikely(!(fpclassify(ua.h) == FP_NORMAL || 3194 fpclassify(ua.h) == FP_ZERO) || 3195 signbit(ua.h))) { 3196 goto soft; 3197 } 3198 } else if (unlikely(!float32_is_zero_or_normal(ua.s) || 3199 float32_is_neg(ua.s))) { 3200 goto soft; 3201 } 3202 ur.h = sqrtf(ua.h); 3203 return ur.s; 3204 3205 soft: 3206 return soft_f32_sqrt(ua.s, s); 3207 } 3208 3209 float64 QEMU_FLATTEN float64_sqrt(float64 xa, float_status *s) 3210 { 3211 union_float64 ua, ur; 3212 3213 ua.s = xa; 3214 if (unlikely(!can_use_fpu(s))) { 3215 goto soft; 3216 } 3217 3218 float64_input_flush1(&ua.s, s); 3219 if (QEMU_HARDFLOAT_1F64_USE_FP) { 3220 if (unlikely(!(fpclassify(ua.h) == FP_NORMAL || 3221 fpclassify(ua.h) == FP_ZERO) || 3222 signbit(ua.h))) { 3223 goto soft; 3224 } 3225 } else if (unlikely(!float64_is_zero_or_normal(ua.s) || 3226 float64_is_neg(ua.s))) { 3227 goto soft; 3228 } 3229 ur.h = sqrt(ua.h); 3230 return ur.s; 3231 3232 soft: 3233 return soft_f64_sqrt(ua.s, s); 3234 } 3235 3236 /*---------------------------------------------------------------------------- 3237 | The pattern for a default generated NaN. 3238 *----------------------------------------------------------------------------*/ 3239 3240 float16 float16_default_nan(float_status *status) 3241 { 3242 FloatParts p = parts_default_nan(status); 3243 p.frac >>= float16_params.frac_shift; 3244 return float16_pack_raw(p); 3245 } 3246 3247 float32 float32_default_nan(float_status *status) 3248 { 3249 FloatParts p = parts_default_nan(status); 3250 p.frac >>= float32_params.frac_shift; 3251 return float32_pack_raw(p); 3252 } 3253 3254 float64 float64_default_nan(float_status *status) 3255 { 3256 FloatParts p = parts_default_nan(status); 3257 p.frac >>= float64_params.frac_shift; 3258 return float64_pack_raw(p); 3259 } 3260 3261 float128 float128_default_nan(float_status *status) 3262 { 3263 FloatParts p = parts_default_nan(status); 3264 float128 r; 3265 3266 /* Extrapolate from the choices made by parts_default_nan to fill 3267 * in the quad-floating format. If the low bit is set, assume we 3268 * want to set all non-snan bits. 3269 */ 3270 r.low = -(p.frac & 1); 3271 r.high = p.frac >> (DECOMPOSED_BINARY_POINT - 48); 3272 r.high |= LIT64(0x7FFF000000000000); 3273 r.high |= (uint64_t)p.sign << 63; 3274 3275 return r; 3276 } 3277 3278 /*---------------------------------------------------------------------------- 3279 | Returns a quiet NaN from a signalling NaN for the floating point value `a'. 3280 *----------------------------------------------------------------------------*/ 3281 3282 float16 float16_silence_nan(float16 a, float_status *status) 3283 { 3284 FloatParts p = float16_unpack_raw(a); 3285 p.frac <<= float16_params.frac_shift; 3286 p = parts_silence_nan(p, status); 3287 p.frac >>= float16_params.frac_shift; 3288 return float16_pack_raw(p); 3289 } 3290 3291 float32 float32_silence_nan(float32 a, float_status *status) 3292 { 3293 FloatParts p = float32_unpack_raw(a); 3294 p.frac <<= float32_params.frac_shift; 3295 p = parts_silence_nan(p, status); 3296 p.frac >>= float32_params.frac_shift; 3297 return float32_pack_raw(p); 3298 } 3299 3300 float64 float64_silence_nan(float64 a, float_status *status) 3301 { 3302 FloatParts p = float64_unpack_raw(a); 3303 p.frac <<= float64_params.frac_shift; 3304 p = parts_silence_nan(p, status); 3305 p.frac >>= float64_params.frac_shift; 3306 return float64_pack_raw(p); 3307 } 3308 3309 /*---------------------------------------------------------------------------- 3310 | Takes a 64-bit fixed-point value `absZ' with binary point between bits 6 3311 | and 7, and returns the properly rounded 32-bit integer corresponding to the 3312 | input. If `zSign' is 1, the input is negated before being converted to an 3313 | integer. Bit 63 of `absZ' must be zero. Ordinarily, the fixed-point input 3314 | is simply rounded to an integer, with the inexact exception raised if the 3315 | input cannot be represented exactly as an integer. However, if the fixed- 3316 | point input is too large, the invalid exception is raised and the largest 3317 | positive or negative integer is returned. 3318 *----------------------------------------------------------------------------*/ 3319 3320 static int32_t roundAndPackInt32(flag zSign, uint64_t absZ, float_status *status) 3321 { 3322 int8_t roundingMode; 3323 flag roundNearestEven; 3324 int8_t roundIncrement, roundBits; 3325 int32_t z; 3326 3327 roundingMode = status->float_rounding_mode; 3328 roundNearestEven = ( roundingMode == float_round_nearest_even ); 3329 switch (roundingMode) { 3330 case float_round_nearest_even: 3331 case float_round_ties_away: 3332 roundIncrement = 0x40; 3333 break; 3334 case float_round_to_zero: 3335 roundIncrement = 0; 3336 break; 3337 case float_round_up: 3338 roundIncrement = zSign ? 0 : 0x7f; 3339 break; 3340 case float_round_down: 3341 roundIncrement = zSign ? 0x7f : 0; 3342 break; 3343 case float_round_to_odd: 3344 roundIncrement = absZ & 0x80 ? 0 : 0x7f; 3345 break; 3346 default: 3347 abort(); 3348 } 3349 roundBits = absZ & 0x7F; 3350 absZ = ( absZ + roundIncrement )>>7; 3351 absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); 3352 z = absZ; 3353 if ( zSign ) z = - z; 3354 if ( ( absZ>>32 ) || ( z && ( ( z < 0 ) ^ zSign ) ) ) { 3355 float_raise(float_flag_invalid, status); 3356 return zSign ? (int32_t) 0x80000000 : 0x7FFFFFFF; 3357 } 3358 if (roundBits) { 3359 status->float_exception_flags |= float_flag_inexact; 3360 } 3361 return z; 3362 3363 } 3364 3365 /*---------------------------------------------------------------------------- 3366 | Takes the 128-bit fixed-point value formed by concatenating `absZ0' and 3367 | `absZ1', with binary point between bits 63 and 64 (between the input words), 3368 | and returns the properly rounded 64-bit integer corresponding to the input. 3369 | If `zSign' is 1, the input is negated before being converted to an integer. 3370 | Ordinarily, the fixed-point input is simply rounded to an integer, with 3371 | the inexact exception raised if the input cannot be represented exactly as 3372 | an integer. However, if the fixed-point input is too large, the invalid 3373 | exception is raised and the largest positive or negative integer is 3374 | returned. 3375 *----------------------------------------------------------------------------*/ 3376 3377 static int64_t roundAndPackInt64(flag zSign, uint64_t absZ0, uint64_t absZ1, 3378 float_status *status) 3379 { 3380 int8_t roundingMode; 3381 flag roundNearestEven, increment; 3382 int64_t z; 3383 3384 roundingMode = status->float_rounding_mode; 3385 roundNearestEven = ( roundingMode == float_round_nearest_even ); 3386 switch (roundingMode) { 3387 case float_round_nearest_even: 3388 case float_round_ties_away: 3389 increment = ((int64_t) absZ1 < 0); 3390 break; 3391 case float_round_to_zero: 3392 increment = 0; 3393 break; 3394 case float_round_up: 3395 increment = !zSign && absZ1; 3396 break; 3397 case float_round_down: 3398 increment = zSign && absZ1; 3399 break; 3400 case float_round_to_odd: 3401 increment = !(absZ0 & 1) && absZ1; 3402 break; 3403 default: 3404 abort(); 3405 } 3406 if ( increment ) { 3407 ++absZ0; 3408 if ( absZ0 == 0 ) goto overflow; 3409 absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven ); 3410 } 3411 z = absZ0; 3412 if ( zSign ) z = - z; 3413 if ( z && ( ( z < 0 ) ^ zSign ) ) { 3414 overflow: 3415 float_raise(float_flag_invalid, status); 3416 return 3417 zSign ? (int64_t) LIT64( 0x8000000000000000 ) 3418 : LIT64( 0x7FFFFFFFFFFFFFFF ); 3419 } 3420 if (absZ1) { 3421 status->float_exception_flags |= float_flag_inexact; 3422 } 3423 return z; 3424 3425 } 3426 3427 /*---------------------------------------------------------------------------- 3428 | Takes the 128-bit fixed-point value formed by concatenating `absZ0' and 3429 | `absZ1', with binary point between bits 63 and 64 (between the input words), 3430 | and returns the properly rounded 64-bit unsigned integer corresponding to the 3431 | input. Ordinarily, the fixed-point input is simply rounded to an integer, 3432 | with the inexact exception raised if the input cannot be represented exactly 3433 | as an integer. However, if the fixed-point input is too large, the invalid 3434 | exception is raised and the largest unsigned integer is returned. 3435 *----------------------------------------------------------------------------*/ 3436 3437 static int64_t roundAndPackUint64(flag zSign, uint64_t absZ0, 3438 uint64_t absZ1, float_status *status) 3439 { 3440 int8_t roundingMode; 3441 flag roundNearestEven, increment; 3442 3443 roundingMode = status->float_rounding_mode; 3444 roundNearestEven = (roundingMode == float_round_nearest_even); 3445 switch (roundingMode) { 3446 case float_round_nearest_even: 3447 case float_round_ties_away: 3448 increment = ((int64_t)absZ1 < 0); 3449 break; 3450 case float_round_to_zero: 3451 increment = 0; 3452 break; 3453 case float_round_up: 3454 increment = !zSign && absZ1; 3455 break; 3456 case float_round_down: 3457 increment = zSign && absZ1; 3458 break; 3459 case float_round_to_odd: 3460 increment = !(absZ0 & 1) && absZ1; 3461 break; 3462 default: 3463 abort(); 3464 } 3465 if (increment) { 3466 ++absZ0; 3467 if (absZ0 == 0) { 3468 float_raise(float_flag_invalid, status); 3469 return LIT64(0xFFFFFFFFFFFFFFFF); 3470 } 3471 absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven); 3472 } 3473 3474 if (zSign && absZ0) { 3475 float_raise(float_flag_invalid, status); 3476 return 0; 3477 } 3478 3479 if (absZ1) { 3480 status->float_exception_flags |= float_flag_inexact; 3481 } 3482 return absZ0; 3483 } 3484 3485 /*---------------------------------------------------------------------------- 3486 | If `a' is denormal and we are in flush-to-zero mode then set the 3487 | input-denormal exception and return zero. Otherwise just return the value. 3488 *----------------------------------------------------------------------------*/ 3489 float32 float32_squash_input_denormal(float32 a, float_status *status) 3490 { 3491 if (status->flush_inputs_to_zero) { 3492 if (extractFloat32Exp(a) == 0 && extractFloat32Frac(a) != 0) { 3493 float_raise(float_flag_input_denormal, status); 3494 return make_float32(float32_val(a) & 0x80000000); 3495 } 3496 } 3497 return a; 3498 } 3499 3500 /*---------------------------------------------------------------------------- 3501 | Normalizes the subnormal single-precision floating-point value represented 3502 | by the denormalized significand `aSig'. The normalized exponent and 3503 | significand are stored at the locations pointed to by `zExpPtr' and 3504 | `zSigPtr', respectively. 3505 *----------------------------------------------------------------------------*/ 3506 3507 static void 3508 normalizeFloat32Subnormal(uint32_t aSig, int *zExpPtr, uint32_t *zSigPtr) 3509 { 3510 int8_t shiftCount; 3511 3512 shiftCount = clz32(aSig) - 8; 3513 *zSigPtr = aSig<<shiftCount; 3514 *zExpPtr = 1 - shiftCount; 3515 3516 } 3517 3518 /*---------------------------------------------------------------------------- 3519 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', 3520 | and significand `zSig', and returns the proper single-precision floating- 3521 | point value corresponding to the abstract input. Ordinarily, the abstract 3522 | value is simply rounded and packed into the single-precision format, with 3523 | the inexact exception raised if the abstract input cannot be represented 3524 | exactly. However, if the abstract value is too large, the overflow and 3525 | inexact exceptions are raised and an infinity or maximal finite value is 3526 | returned. If the abstract value is too small, the input value is rounded to 3527 | a subnormal number, and the underflow and inexact exceptions are raised if 3528 | the abstract input cannot be represented exactly as a subnormal single- 3529 | precision floating-point number. 3530 | The input significand `zSig' has its binary point between bits 30 3531 | and 29, which is 7 bits to the left of the usual location. This shifted 3532 | significand must be normalized or smaller. If `zSig' is not normalized, 3533 | `zExp' must be 0; in that case, the result returned is a subnormal number, 3534 | and it must not require rounding. In the usual case that `zSig' is 3535 | normalized, `zExp' must be 1 less than the ``true'' floating-point exponent. 3536 | The handling of underflow and overflow follows the IEC/IEEE Standard for 3537 | Binary Floating-Point Arithmetic. 3538 *----------------------------------------------------------------------------*/ 3539 3540 static float32 roundAndPackFloat32(flag zSign, int zExp, uint32_t zSig, 3541 float_status *status) 3542 { 3543 int8_t roundingMode; 3544 flag roundNearestEven; 3545 int8_t roundIncrement, roundBits; 3546 flag isTiny; 3547 3548 roundingMode = status->float_rounding_mode; 3549 roundNearestEven = ( roundingMode == float_round_nearest_even ); 3550 switch (roundingMode) { 3551 case float_round_nearest_even: 3552 case float_round_ties_away: 3553 roundIncrement = 0x40; 3554 break; 3555 case float_round_to_zero: 3556 roundIncrement = 0; 3557 break; 3558 case float_round_up: 3559 roundIncrement = zSign ? 0 : 0x7f; 3560 break; 3561 case float_round_down: 3562 roundIncrement = zSign ? 0x7f : 0; 3563 break; 3564 case float_round_to_odd: 3565 roundIncrement = zSig & 0x80 ? 0 : 0x7f; 3566 break; 3567 default: 3568 abort(); 3569 break; 3570 } 3571 roundBits = zSig & 0x7F; 3572 if ( 0xFD <= (uint16_t) zExp ) { 3573 if ( ( 0xFD < zExp ) 3574 || ( ( zExp == 0xFD ) 3575 && ( (int32_t) ( zSig + roundIncrement ) < 0 ) ) 3576 ) { 3577 bool overflow_to_inf = roundingMode != float_round_to_odd && 3578 roundIncrement != 0; 3579 float_raise(float_flag_overflow | float_flag_inexact, status); 3580 return packFloat32(zSign, 0xFF, -!overflow_to_inf); 3581 } 3582 if ( zExp < 0 ) { 3583 if (status->flush_to_zero) { 3584 float_raise(float_flag_output_denormal, status); 3585 return packFloat32(zSign, 0, 0); 3586 } 3587 isTiny = 3588 (status->float_detect_tininess 3589 == float_tininess_before_rounding) 3590 || ( zExp < -1 ) 3591 || ( zSig + roundIncrement < 0x80000000 ); 3592 shift32RightJamming( zSig, - zExp, &zSig ); 3593 zExp = 0; 3594 roundBits = zSig & 0x7F; 3595 if (isTiny && roundBits) { 3596 float_raise(float_flag_underflow, status); 3597 } 3598 if (roundingMode == float_round_to_odd) { 3599 /* 3600 * For round-to-odd case, the roundIncrement depends on 3601 * zSig which just changed. 3602 */ 3603 roundIncrement = zSig & 0x80 ? 0 : 0x7f; 3604 } 3605 } 3606 } 3607 if (roundBits) { 3608 status->float_exception_flags |= float_flag_inexact; 3609 } 3610 zSig = ( zSig + roundIncrement )>>7; 3611 zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); 3612 if ( zSig == 0 ) zExp = 0; 3613 return packFloat32( zSign, zExp, zSig ); 3614 3615 } 3616 3617 /*---------------------------------------------------------------------------- 3618 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', 3619 | and significand `zSig', and returns the proper single-precision floating- 3620 | point value corresponding to the abstract input. This routine is just like 3621 | `roundAndPackFloat32' except that `zSig' does not have to be normalized. 3622 | Bit 31 of `zSig' must be zero, and `zExp' must be 1 less than the ``true'' 3623 | floating-point exponent. 3624 *----------------------------------------------------------------------------*/ 3625 3626 static float32 3627 normalizeRoundAndPackFloat32(flag zSign, int zExp, uint32_t zSig, 3628 float_status *status) 3629 { 3630 int8_t shiftCount; 3631 3632 shiftCount = clz32(zSig) - 1; 3633 return roundAndPackFloat32(zSign, zExp - shiftCount, zSig<<shiftCount, 3634 status); 3635 3636 } 3637 3638 /*---------------------------------------------------------------------------- 3639 | If `a' is denormal and we are in flush-to-zero mode then set the 3640 | input-denormal exception and return zero. Otherwise just return the value. 3641 *----------------------------------------------------------------------------*/ 3642 float64 float64_squash_input_denormal(float64 a, float_status *status) 3643 { 3644 if (status->flush_inputs_to_zero) { 3645 if (extractFloat64Exp(a) == 0 && extractFloat64Frac(a) != 0) { 3646 float_raise(float_flag_input_denormal, status); 3647 return make_float64(float64_val(a) & (1ULL << 63)); 3648 } 3649 } 3650 return a; 3651 } 3652 3653 /*---------------------------------------------------------------------------- 3654 | Normalizes the subnormal double-precision floating-point value represented 3655 | by the denormalized significand `aSig'. The normalized exponent and 3656 | significand are stored at the locations pointed to by `zExpPtr' and 3657 | `zSigPtr', respectively. 3658 *----------------------------------------------------------------------------*/ 3659 3660 static void 3661 normalizeFloat64Subnormal(uint64_t aSig, int *zExpPtr, uint64_t *zSigPtr) 3662 { 3663 int8_t shiftCount; 3664 3665 shiftCount = clz64(aSig) - 11; 3666 *zSigPtr = aSig<<shiftCount; 3667 *zExpPtr = 1 - shiftCount; 3668 3669 } 3670 3671 /*---------------------------------------------------------------------------- 3672 | Packs the sign `zSign', exponent `zExp', and significand `zSig' into a 3673 | double-precision floating-point value, returning the result. After being 3674 | shifted into the proper positions, the three fields are simply added 3675 | together to form the result. This means that any integer portion of `zSig' 3676 | will be added into the exponent. Since a properly normalized significand 3677 | will have an integer portion equal to 1, the `zExp' input should be 1 less 3678 | than the desired result exponent whenever `zSig' is a complete, normalized 3679 | significand. 3680 *----------------------------------------------------------------------------*/ 3681 3682 static inline float64 packFloat64(flag zSign, int zExp, uint64_t zSig) 3683 { 3684 3685 return make_float64( 3686 ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) zExp )<<52 ) + zSig); 3687 3688 } 3689 3690 /*---------------------------------------------------------------------------- 3691 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', 3692 | and significand `zSig', and returns the proper double-precision floating- 3693 | point value corresponding to the abstract input. Ordinarily, the abstract 3694 | value is simply rounded and packed into the double-precision format, with 3695 | the inexact exception raised if the abstract input cannot be represented 3696 | exactly. However, if the abstract value is too large, the overflow and 3697 | inexact exceptions are raised and an infinity or maximal finite value is 3698 | returned. If the abstract value is too small, the input value is rounded to 3699 | a subnormal number, and the underflow and inexact exceptions are raised if 3700 | the abstract input cannot be represented exactly as a subnormal double- 3701 | precision floating-point number. 3702 | The input significand `zSig' has its binary point between bits 62 3703 | and 61, which is 10 bits to the left of the usual location. This shifted 3704 | significand must be normalized or smaller. If `zSig' is not normalized, 3705 | `zExp' must be 0; in that case, the result returned is a subnormal number, 3706 | and it must not require rounding. In the usual case that `zSig' is 3707 | normalized, `zExp' must be 1 less than the ``true'' floating-point exponent. 3708 | The handling of underflow and overflow follows the IEC/IEEE Standard for 3709 | Binary Floating-Point Arithmetic. 3710 *----------------------------------------------------------------------------*/ 3711 3712 static float64 roundAndPackFloat64(flag zSign, int zExp, uint64_t zSig, 3713 float_status *status) 3714 { 3715 int8_t roundingMode; 3716 flag roundNearestEven; 3717 int roundIncrement, roundBits; 3718 flag isTiny; 3719 3720 roundingMode = status->float_rounding_mode; 3721 roundNearestEven = ( roundingMode == float_round_nearest_even ); 3722 switch (roundingMode) { 3723 case float_round_nearest_even: 3724 case float_round_ties_away: 3725 roundIncrement = 0x200; 3726 break; 3727 case float_round_to_zero: 3728 roundIncrement = 0; 3729 break; 3730 case float_round_up: 3731 roundIncrement = zSign ? 0 : 0x3ff; 3732 break; 3733 case float_round_down: 3734 roundIncrement = zSign ? 0x3ff : 0; 3735 break; 3736 case float_round_to_odd: 3737 roundIncrement = (zSig & 0x400) ? 0 : 0x3ff; 3738 break; 3739 default: 3740 abort(); 3741 } 3742 roundBits = zSig & 0x3FF; 3743 if ( 0x7FD <= (uint16_t) zExp ) { 3744 if ( ( 0x7FD < zExp ) 3745 || ( ( zExp == 0x7FD ) 3746 && ( (int64_t) ( zSig + roundIncrement ) < 0 ) ) 3747 ) { 3748 bool overflow_to_inf = roundingMode != float_round_to_odd && 3749 roundIncrement != 0; 3750 float_raise(float_flag_overflow | float_flag_inexact, status); 3751 return packFloat64(zSign, 0x7FF, -(!overflow_to_inf)); 3752 } 3753 if ( zExp < 0 ) { 3754 if (status->flush_to_zero) { 3755 float_raise(float_flag_output_denormal, status); 3756 return packFloat64(zSign, 0, 0); 3757 } 3758 isTiny = 3759 (status->float_detect_tininess 3760 == float_tininess_before_rounding) 3761 || ( zExp < -1 ) 3762 || ( zSig + roundIncrement < LIT64( 0x8000000000000000 ) ); 3763 shift64RightJamming( zSig, - zExp, &zSig ); 3764 zExp = 0; 3765 roundBits = zSig & 0x3FF; 3766 if (isTiny && roundBits) { 3767 float_raise(float_flag_underflow, status); 3768 } 3769 if (roundingMode == float_round_to_odd) { 3770 /* 3771 * For round-to-odd case, the roundIncrement depends on 3772 * zSig which just changed. 3773 */ 3774 roundIncrement = (zSig & 0x400) ? 0 : 0x3ff; 3775 } 3776 } 3777 } 3778 if (roundBits) { 3779 status->float_exception_flags |= float_flag_inexact; 3780 } 3781 zSig = ( zSig + roundIncrement )>>10; 3782 zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven ); 3783 if ( zSig == 0 ) zExp = 0; 3784 return packFloat64( zSign, zExp, zSig ); 3785 3786 } 3787 3788 /*---------------------------------------------------------------------------- 3789 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', 3790 | and significand `zSig', and returns the proper double-precision floating- 3791 | point value corresponding to the abstract input. This routine is just like 3792 | `roundAndPackFloat64' except that `zSig' does not have to be normalized. 3793 | Bit 63 of `zSig' must be zero, and `zExp' must be 1 less than the ``true'' 3794 | floating-point exponent. 3795 *----------------------------------------------------------------------------*/ 3796 3797 static float64 3798 normalizeRoundAndPackFloat64(flag zSign, int zExp, uint64_t zSig, 3799 float_status *status) 3800 { 3801 int8_t shiftCount; 3802 3803 shiftCount = clz64(zSig) - 1; 3804 return roundAndPackFloat64(zSign, zExp - shiftCount, zSig<<shiftCount, 3805 status); 3806 3807 } 3808 3809 /*---------------------------------------------------------------------------- 3810 | Normalizes the subnormal extended double-precision floating-point value 3811 | represented by the denormalized significand `aSig'. The normalized exponent 3812 | and significand are stored at the locations pointed to by `zExpPtr' and 3813 | `zSigPtr', respectively. 3814 *----------------------------------------------------------------------------*/ 3815 3816 void normalizeFloatx80Subnormal(uint64_t aSig, int32_t *zExpPtr, 3817 uint64_t *zSigPtr) 3818 { 3819 int8_t shiftCount; 3820 3821 shiftCount = clz64(aSig); 3822 *zSigPtr = aSig<<shiftCount; 3823 *zExpPtr = 1 - shiftCount; 3824 } 3825 3826 /*---------------------------------------------------------------------------- 3827 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', 3828 | and extended significand formed by the concatenation of `zSig0' and `zSig1', 3829 | and returns the proper extended double-precision floating-point value 3830 | corresponding to the abstract input. Ordinarily, the abstract value is 3831 | rounded and packed into the extended double-precision format, with the 3832 | inexact exception raised if the abstract input cannot be represented 3833 | exactly. However, if the abstract value is too large, the overflow and 3834 | inexact exceptions are raised and an infinity or maximal finite value is 3835 | returned. If the abstract value is too small, the input value is rounded to 3836 | a subnormal number, and the underflow and inexact exceptions are raised if 3837 | the abstract input cannot be represented exactly as a subnormal extended 3838 | double-precision floating-point number. 3839 | If `roundingPrecision' is 32 or 64, the result is rounded to the same 3840 | number of bits as single or double precision, respectively. Otherwise, the 3841 | result is rounded to the full precision of the extended double-precision 3842 | format. 3843 | The input significand must be normalized or smaller. If the input 3844 | significand is not normalized, `zExp' must be 0; in that case, the result 3845 | returned is a subnormal number, and it must not require rounding. The 3846 | handling of underflow and overflow follows the IEC/IEEE Standard for Binary 3847 | Floating-Point Arithmetic. 3848 *----------------------------------------------------------------------------*/ 3849 3850 floatx80 roundAndPackFloatx80(int8_t roundingPrecision, flag zSign, 3851 int32_t zExp, uint64_t zSig0, uint64_t zSig1, 3852 float_status *status) 3853 { 3854 int8_t roundingMode; 3855 flag roundNearestEven, increment, isTiny; 3856 int64_t roundIncrement, roundMask, roundBits; 3857 3858 roundingMode = status->float_rounding_mode; 3859 roundNearestEven = ( roundingMode == float_round_nearest_even ); 3860 if ( roundingPrecision == 80 ) goto precision80; 3861 if ( roundingPrecision == 64 ) { 3862 roundIncrement = LIT64( 0x0000000000000400 ); 3863 roundMask = LIT64( 0x00000000000007FF ); 3864 } 3865 else if ( roundingPrecision == 32 ) { 3866 roundIncrement = LIT64( 0x0000008000000000 ); 3867 roundMask = LIT64( 0x000000FFFFFFFFFF ); 3868 } 3869 else { 3870 goto precision80; 3871 } 3872 zSig0 |= ( zSig1 != 0 ); 3873 switch (roundingMode) { 3874 case float_round_nearest_even: 3875 case float_round_ties_away: 3876 break; 3877 case float_round_to_zero: 3878 roundIncrement = 0; 3879 break; 3880 case float_round_up: 3881 roundIncrement = zSign ? 0 : roundMask; 3882 break; 3883 case float_round_down: 3884 roundIncrement = zSign ? roundMask : 0; 3885 break; 3886 default: 3887 abort(); 3888 } 3889 roundBits = zSig0 & roundMask; 3890 if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) { 3891 if ( ( 0x7FFE < zExp ) 3892 || ( ( zExp == 0x7FFE ) && ( zSig0 + roundIncrement < zSig0 ) ) 3893 ) { 3894 goto overflow; 3895 } 3896 if ( zExp <= 0 ) { 3897 if (status->flush_to_zero) { 3898 float_raise(float_flag_output_denormal, status); 3899 return packFloatx80(zSign, 0, 0); 3900 } 3901 isTiny = 3902 (status->float_detect_tininess 3903 == float_tininess_before_rounding) 3904 || ( zExp < 0 ) 3905 || ( zSig0 <= zSig0 + roundIncrement ); 3906 shift64RightJamming( zSig0, 1 - zExp, &zSig0 ); 3907 zExp = 0; 3908 roundBits = zSig0 & roundMask; 3909 if (isTiny && roundBits) { 3910 float_raise(float_flag_underflow, status); 3911 } 3912 if (roundBits) { 3913 status->float_exception_flags |= float_flag_inexact; 3914 } 3915 zSig0 += roundIncrement; 3916 if ( (int64_t) zSig0 < 0 ) zExp = 1; 3917 roundIncrement = roundMask + 1; 3918 if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) { 3919 roundMask |= roundIncrement; 3920 } 3921 zSig0 &= ~ roundMask; 3922 return packFloatx80( zSign, zExp, zSig0 ); 3923 } 3924 } 3925 if (roundBits) { 3926 status->float_exception_flags |= float_flag_inexact; 3927 } 3928 zSig0 += roundIncrement; 3929 if ( zSig0 < roundIncrement ) { 3930 ++zExp; 3931 zSig0 = LIT64( 0x8000000000000000 ); 3932 } 3933 roundIncrement = roundMask + 1; 3934 if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) { 3935 roundMask |= roundIncrement; 3936 } 3937 zSig0 &= ~ roundMask; 3938 if ( zSig0 == 0 ) zExp = 0; 3939 return packFloatx80( zSign, zExp, zSig0 ); 3940 precision80: 3941 switch (roundingMode) { 3942 case float_round_nearest_even: 3943 case float_round_ties_away: 3944 increment = ((int64_t)zSig1 < 0); 3945 break; 3946 case float_round_to_zero: 3947 increment = 0; 3948 break; 3949 case float_round_up: 3950 increment = !zSign && zSig1; 3951 break; 3952 case float_round_down: 3953 increment = zSign && zSig1; 3954 break; 3955 default: 3956 abort(); 3957 } 3958 if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) { 3959 if ( ( 0x7FFE < zExp ) 3960 || ( ( zExp == 0x7FFE ) 3961 && ( zSig0 == LIT64( 0xFFFFFFFFFFFFFFFF ) ) 3962 && increment 3963 ) 3964 ) { 3965 roundMask = 0; 3966 overflow: 3967 float_raise(float_flag_overflow | float_flag_inexact, status); 3968 if ( ( roundingMode == float_round_to_zero ) 3969 || ( zSign && ( roundingMode == float_round_up ) ) 3970 || ( ! zSign && ( roundingMode == float_round_down ) ) 3971 ) { 3972 return packFloatx80( zSign, 0x7FFE, ~ roundMask ); 3973 } 3974 return packFloatx80(zSign, 3975 floatx80_infinity_high, 3976 floatx80_infinity_low); 3977 } 3978 if ( zExp <= 0 ) { 3979 isTiny = 3980 (status->float_detect_tininess 3981 == float_tininess_before_rounding) 3982 || ( zExp < 0 ) 3983 || ! increment 3984 || ( zSig0 < LIT64( 0xFFFFFFFFFFFFFFFF ) ); 3985 shift64ExtraRightJamming( zSig0, zSig1, 1 - zExp, &zSig0, &zSig1 ); 3986 zExp = 0; 3987 if (isTiny && zSig1) { 3988 float_raise(float_flag_underflow, status); 3989 } 3990 if (zSig1) { 3991 status->float_exception_flags |= float_flag_inexact; 3992 } 3993 switch (roundingMode) { 3994 case float_round_nearest_even: 3995 case float_round_ties_away: 3996 increment = ((int64_t)zSig1 < 0); 3997 break; 3998 case float_round_to_zero: 3999 increment = 0; 4000 break; 4001 case float_round_up: 4002 increment = !zSign && zSig1; 4003 break; 4004 case float_round_down: 4005 increment = zSign && zSig1; 4006 break; 4007 default: 4008 abort(); 4009 } 4010 if ( increment ) { 4011 ++zSig0; 4012 zSig0 &= 4013 ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); 4014 if ( (int64_t) zSig0 < 0 ) zExp = 1; 4015 } 4016 return packFloatx80( zSign, zExp, zSig0 ); 4017 } 4018 } 4019 if (zSig1) { 4020 status->float_exception_flags |= float_flag_inexact; 4021 } 4022 if ( increment ) { 4023 ++zSig0; 4024 if ( zSig0 == 0 ) { 4025 ++zExp; 4026 zSig0 = LIT64( 0x8000000000000000 ); 4027 } 4028 else { 4029 zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); 4030 } 4031 } 4032 else { 4033 if ( zSig0 == 0 ) zExp = 0; 4034 } 4035 return packFloatx80( zSign, zExp, zSig0 ); 4036 4037 } 4038 4039 /*---------------------------------------------------------------------------- 4040 | Takes an abstract floating-point value having sign `zSign', exponent 4041 | `zExp', and significand formed by the concatenation of `zSig0' and `zSig1', 4042 | and returns the proper extended double-precision floating-point value 4043 | corresponding to the abstract input. This routine is just like 4044 | `roundAndPackFloatx80' except that the input significand does not have to be 4045 | normalized. 4046 *----------------------------------------------------------------------------*/ 4047 4048 floatx80 normalizeRoundAndPackFloatx80(int8_t roundingPrecision, 4049 flag zSign, int32_t zExp, 4050 uint64_t zSig0, uint64_t zSig1, 4051 float_status *status) 4052 { 4053 int8_t shiftCount; 4054 4055 if ( zSig0 == 0 ) { 4056 zSig0 = zSig1; 4057 zSig1 = 0; 4058 zExp -= 64; 4059 } 4060 shiftCount = clz64(zSig0); 4061 shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 ); 4062 zExp -= shiftCount; 4063 return roundAndPackFloatx80(roundingPrecision, zSign, zExp, 4064 zSig0, zSig1, status); 4065 4066 } 4067 4068 /*---------------------------------------------------------------------------- 4069 | Returns the least-significant 64 fraction bits of the quadruple-precision 4070 | floating-point value `a'. 4071 *----------------------------------------------------------------------------*/ 4072 4073 static inline uint64_t extractFloat128Frac1( float128 a ) 4074 { 4075 4076 return a.low; 4077 4078 } 4079 4080 /*---------------------------------------------------------------------------- 4081 | Returns the most-significant 48 fraction bits of the quadruple-precision 4082 | floating-point value `a'. 4083 *----------------------------------------------------------------------------*/ 4084 4085 static inline uint64_t extractFloat128Frac0( float128 a ) 4086 { 4087 4088 return a.high & LIT64( 0x0000FFFFFFFFFFFF ); 4089 4090 } 4091 4092 /*---------------------------------------------------------------------------- 4093 | Returns the exponent bits of the quadruple-precision floating-point value 4094 | `a'. 4095 *----------------------------------------------------------------------------*/ 4096 4097 static inline int32_t extractFloat128Exp( float128 a ) 4098 { 4099 4100 return ( a.high>>48 ) & 0x7FFF; 4101 4102 } 4103 4104 /*---------------------------------------------------------------------------- 4105 | Returns the sign bit of the quadruple-precision floating-point value `a'. 4106 *----------------------------------------------------------------------------*/ 4107 4108 static inline flag extractFloat128Sign( float128 a ) 4109 { 4110 4111 return a.high>>63; 4112 4113 } 4114 4115 /*---------------------------------------------------------------------------- 4116 | Normalizes the subnormal quadruple-precision floating-point value 4117 | represented by the denormalized significand formed by the concatenation of 4118 | `aSig0' and `aSig1'. The normalized exponent is stored at the location 4119 | pointed to by `zExpPtr'. The most significant 49 bits of the normalized 4120 | significand are stored at the location pointed to by `zSig0Ptr', and the 4121 | least significant 64 bits of the normalized significand are stored at the 4122 | location pointed to by `zSig1Ptr'. 4123 *----------------------------------------------------------------------------*/ 4124 4125 static void 4126 normalizeFloat128Subnormal( 4127 uint64_t aSig0, 4128 uint64_t aSig1, 4129 int32_t *zExpPtr, 4130 uint64_t *zSig0Ptr, 4131 uint64_t *zSig1Ptr 4132 ) 4133 { 4134 int8_t shiftCount; 4135 4136 if ( aSig0 == 0 ) { 4137 shiftCount = clz64(aSig1) - 15; 4138 if ( shiftCount < 0 ) { 4139 *zSig0Ptr = aSig1>>( - shiftCount ); 4140 *zSig1Ptr = aSig1<<( shiftCount & 63 ); 4141 } 4142 else { 4143 *zSig0Ptr = aSig1<<shiftCount; 4144 *zSig1Ptr = 0; 4145 } 4146 *zExpPtr = - shiftCount - 63; 4147 } 4148 else { 4149 shiftCount = clz64(aSig0) - 15; 4150 shortShift128Left( aSig0, aSig1, shiftCount, zSig0Ptr, zSig1Ptr ); 4151 *zExpPtr = 1 - shiftCount; 4152 } 4153 4154 } 4155 4156 /*---------------------------------------------------------------------------- 4157 | Packs the sign `zSign', the exponent `zExp', and the significand formed 4158 | by the concatenation of `zSig0' and `zSig1' into a quadruple-precision 4159 | floating-point value, returning the result. After being shifted into the 4160 | proper positions, the three fields `zSign', `zExp', and `zSig0' are simply 4161 | added together to form the most significant 32 bits of the result. This 4162 | means that any integer portion of `zSig0' will be added into the exponent. 4163 | Since a properly normalized significand will have an integer portion equal 4164 | to 1, the `zExp' input should be 1 less than the desired result exponent 4165 | whenever `zSig0' and `zSig1' concatenated form a complete, normalized 4166 | significand. 4167 *----------------------------------------------------------------------------*/ 4168 4169 static inline float128 4170 packFloat128( flag zSign, int32_t zExp, uint64_t zSig0, uint64_t zSig1 ) 4171 { 4172 float128 z; 4173 4174 z.low = zSig1; 4175 z.high = ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) zExp )<<48 ) + zSig0; 4176 return z; 4177 4178 } 4179 4180 /*---------------------------------------------------------------------------- 4181 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', 4182 | and extended significand formed by the concatenation of `zSig0', `zSig1', 4183 | and `zSig2', and returns the proper quadruple-precision floating-point value 4184 | corresponding to the abstract input. Ordinarily, the abstract value is 4185 | simply rounded and packed into the quadruple-precision format, with the 4186 | inexact exception raised if the abstract input cannot be represented 4187 | exactly. However, if the abstract value is too large, the overflow and 4188 | inexact exceptions are raised and an infinity or maximal finite value is 4189 | returned. If the abstract value is too small, the input value is rounded to 4190 | a subnormal number, and the underflow and inexact exceptions are raised if 4191 | the abstract input cannot be represented exactly as a subnormal quadruple- 4192 | precision floating-point number. 4193 | The input significand must be normalized or smaller. If the input 4194 | significand is not normalized, `zExp' must be 0; in that case, the result 4195 | returned is a subnormal number, and it must not require rounding. In the 4196 | usual case that the input significand is normalized, `zExp' must be 1 less 4197 | than the ``true'' floating-point exponent. The handling of underflow and 4198 | overflow follows the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4199 *----------------------------------------------------------------------------*/ 4200 4201 static float128 roundAndPackFloat128(flag zSign, int32_t zExp, 4202 uint64_t zSig0, uint64_t zSig1, 4203 uint64_t zSig2, float_status *status) 4204 { 4205 int8_t roundingMode; 4206 flag roundNearestEven, increment, isTiny; 4207 4208 roundingMode = status->float_rounding_mode; 4209 roundNearestEven = ( roundingMode == float_round_nearest_even ); 4210 switch (roundingMode) { 4211 case float_round_nearest_even: 4212 case float_round_ties_away: 4213 increment = ((int64_t)zSig2 < 0); 4214 break; 4215 case float_round_to_zero: 4216 increment = 0; 4217 break; 4218 case float_round_up: 4219 increment = !zSign && zSig2; 4220 break; 4221 case float_round_down: 4222 increment = zSign && zSig2; 4223 break; 4224 case float_round_to_odd: 4225 increment = !(zSig1 & 0x1) && zSig2; 4226 break; 4227 default: 4228 abort(); 4229 } 4230 if ( 0x7FFD <= (uint32_t) zExp ) { 4231 if ( ( 0x7FFD < zExp ) 4232 || ( ( zExp == 0x7FFD ) 4233 && eq128( 4234 LIT64( 0x0001FFFFFFFFFFFF ), 4235 LIT64( 0xFFFFFFFFFFFFFFFF ), 4236 zSig0, 4237 zSig1 4238 ) 4239 && increment 4240 ) 4241 ) { 4242 float_raise(float_flag_overflow | float_flag_inexact, status); 4243 if ( ( roundingMode == float_round_to_zero ) 4244 || ( zSign && ( roundingMode == float_round_up ) ) 4245 || ( ! zSign && ( roundingMode == float_round_down ) ) 4246 || (roundingMode == float_round_to_odd) 4247 ) { 4248 return 4249 packFloat128( 4250 zSign, 4251 0x7FFE, 4252 LIT64( 0x0000FFFFFFFFFFFF ), 4253 LIT64( 0xFFFFFFFFFFFFFFFF ) 4254 ); 4255 } 4256 return packFloat128( zSign, 0x7FFF, 0, 0 ); 4257 } 4258 if ( zExp < 0 ) { 4259 if (status->flush_to_zero) { 4260 float_raise(float_flag_output_denormal, status); 4261 return packFloat128(zSign, 0, 0, 0); 4262 } 4263 isTiny = 4264 (status->float_detect_tininess 4265 == float_tininess_before_rounding) 4266 || ( zExp < -1 ) 4267 || ! increment 4268 || lt128( 4269 zSig0, 4270 zSig1, 4271 LIT64( 0x0001FFFFFFFFFFFF ), 4272 LIT64( 0xFFFFFFFFFFFFFFFF ) 4273 ); 4274 shift128ExtraRightJamming( 4275 zSig0, zSig1, zSig2, - zExp, &zSig0, &zSig1, &zSig2 ); 4276 zExp = 0; 4277 if (isTiny && zSig2) { 4278 float_raise(float_flag_underflow, status); 4279 } 4280 switch (roundingMode) { 4281 case float_round_nearest_even: 4282 case float_round_ties_away: 4283 increment = ((int64_t)zSig2 < 0); 4284 break; 4285 case float_round_to_zero: 4286 increment = 0; 4287 break; 4288 case float_round_up: 4289 increment = !zSign && zSig2; 4290 break; 4291 case float_round_down: 4292 increment = zSign && zSig2; 4293 break; 4294 case float_round_to_odd: 4295 increment = !(zSig1 & 0x1) && zSig2; 4296 break; 4297 default: 4298 abort(); 4299 } 4300 } 4301 } 4302 if (zSig2) { 4303 status->float_exception_flags |= float_flag_inexact; 4304 } 4305 if ( increment ) { 4306 add128( zSig0, zSig1, 0, 1, &zSig0, &zSig1 ); 4307 zSig1 &= ~ ( ( zSig2 + zSig2 == 0 ) & roundNearestEven ); 4308 } 4309 else { 4310 if ( ( zSig0 | zSig1 ) == 0 ) zExp = 0; 4311 } 4312 return packFloat128( zSign, zExp, zSig0, zSig1 ); 4313 4314 } 4315 4316 /*---------------------------------------------------------------------------- 4317 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', 4318 | and significand formed by the concatenation of `zSig0' and `zSig1', and 4319 | returns the proper quadruple-precision floating-point value corresponding 4320 | to the abstract input. This routine is just like `roundAndPackFloat128' 4321 | except that the input significand has fewer bits and does not have to be 4322 | normalized. In all cases, `zExp' must be 1 less than the ``true'' floating- 4323 | point exponent. 4324 *----------------------------------------------------------------------------*/ 4325 4326 static float128 normalizeRoundAndPackFloat128(flag zSign, int32_t zExp, 4327 uint64_t zSig0, uint64_t zSig1, 4328 float_status *status) 4329 { 4330 int8_t shiftCount; 4331 uint64_t zSig2; 4332 4333 if ( zSig0 == 0 ) { 4334 zSig0 = zSig1; 4335 zSig1 = 0; 4336 zExp -= 64; 4337 } 4338 shiftCount = clz64(zSig0) - 15; 4339 if ( 0 <= shiftCount ) { 4340 zSig2 = 0; 4341 shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 ); 4342 } 4343 else { 4344 shift128ExtraRightJamming( 4345 zSig0, zSig1, 0, - shiftCount, &zSig0, &zSig1, &zSig2 ); 4346 } 4347 zExp -= shiftCount; 4348 return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status); 4349 4350 } 4351 4352 4353 /*---------------------------------------------------------------------------- 4354 | Returns the result of converting the 32-bit two's complement integer `a' 4355 | to the extended double-precision floating-point format. The conversion 4356 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 4357 | Arithmetic. 4358 *----------------------------------------------------------------------------*/ 4359 4360 floatx80 int32_to_floatx80(int32_t a, float_status *status) 4361 { 4362 flag zSign; 4363 uint32_t absA; 4364 int8_t shiftCount; 4365 uint64_t zSig; 4366 4367 if ( a == 0 ) return packFloatx80( 0, 0, 0 ); 4368 zSign = ( a < 0 ); 4369 absA = zSign ? - a : a; 4370 shiftCount = clz32(absA) + 32; 4371 zSig = absA; 4372 return packFloatx80( zSign, 0x403E - shiftCount, zSig<<shiftCount ); 4373 4374 } 4375 4376 /*---------------------------------------------------------------------------- 4377 | Returns the result of converting the 32-bit two's complement integer `a' to 4378 | the quadruple-precision floating-point format. The conversion is performed 4379 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4380 *----------------------------------------------------------------------------*/ 4381 4382 float128 int32_to_float128(int32_t a, float_status *status) 4383 { 4384 flag zSign; 4385 uint32_t absA; 4386 int8_t shiftCount; 4387 uint64_t zSig0; 4388 4389 if ( a == 0 ) return packFloat128( 0, 0, 0, 0 ); 4390 zSign = ( a < 0 ); 4391 absA = zSign ? - a : a; 4392 shiftCount = clz32(absA) + 17; 4393 zSig0 = absA; 4394 return packFloat128( zSign, 0x402E - shiftCount, zSig0<<shiftCount, 0 ); 4395 4396 } 4397 4398 /*---------------------------------------------------------------------------- 4399 | Returns the result of converting the 64-bit two's complement integer `a' 4400 | to the extended double-precision floating-point format. The conversion 4401 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 4402 | Arithmetic. 4403 *----------------------------------------------------------------------------*/ 4404 4405 floatx80 int64_to_floatx80(int64_t a, float_status *status) 4406 { 4407 flag zSign; 4408 uint64_t absA; 4409 int8_t shiftCount; 4410 4411 if ( a == 0 ) return packFloatx80( 0, 0, 0 ); 4412 zSign = ( a < 0 ); 4413 absA = zSign ? - a : a; 4414 shiftCount = clz64(absA); 4415 return packFloatx80( zSign, 0x403E - shiftCount, absA<<shiftCount ); 4416 4417 } 4418 4419 /*---------------------------------------------------------------------------- 4420 | Returns the result of converting the 64-bit two's complement integer `a' to 4421 | the quadruple-precision floating-point format. The conversion is performed 4422 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4423 *----------------------------------------------------------------------------*/ 4424 4425 float128 int64_to_float128(int64_t a, float_status *status) 4426 { 4427 flag zSign; 4428 uint64_t absA; 4429 int8_t shiftCount; 4430 int32_t zExp; 4431 uint64_t zSig0, zSig1; 4432 4433 if ( a == 0 ) return packFloat128( 0, 0, 0, 0 ); 4434 zSign = ( a < 0 ); 4435 absA = zSign ? - a : a; 4436 shiftCount = clz64(absA) + 49; 4437 zExp = 0x406E - shiftCount; 4438 if ( 64 <= shiftCount ) { 4439 zSig1 = 0; 4440 zSig0 = absA; 4441 shiftCount -= 64; 4442 } 4443 else { 4444 zSig1 = absA; 4445 zSig0 = 0; 4446 } 4447 shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 ); 4448 return packFloat128( zSign, zExp, zSig0, zSig1 ); 4449 4450 } 4451 4452 /*---------------------------------------------------------------------------- 4453 | Returns the result of converting the 64-bit unsigned integer `a' 4454 | to the quadruple-precision floating-point format. The conversion is performed 4455 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4456 *----------------------------------------------------------------------------*/ 4457 4458 float128 uint64_to_float128(uint64_t a, float_status *status) 4459 { 4460 if (a == 0) { 4461 return float128_zero; 4462 } 4463 return normalizeRoundAndPackFloat128(0, 0x406E, 0, a, status); 4464 } 4465 4466 /*---------------------------------------------------------------------------- 4467 | Returns the result of converting the single-precision floating-point value 4468 | `a' to the extended double-precision floating-point format. The conversion 4469 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 4470 | Arithmetic. 4471 *----------------------------------------------------------------------------*/ 4472 4473 floatx80 float32_to_floatx80(float32 a, float_status *status) 4474 { 4475 flag aSign; 4476 int aExp; 4477 uint32_t aSig; 4478 4479 a = float32_squash_input_denormal(a, status); 4480 aSig = extractFloat32Frac( a ); 4481 aExp = extractFloat32Exp( a ); 4482 aSign = extractFloat32Sign( a ); 4483 if ( aExp == 0xFF ) { 4484 if (aSig) { 4485 return commonNaNToFloatx80(float32ToCommonNaN(a, status), status); 4486 } 4487 return packFloatx80(aSign, 4488 floatx80_infinity_high, 4489 floatx80_infinity_low); 4490 } 4491 if ( aExp == 0 ) { 4492 if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 ); 4493 normalizeFloat32Subnormal( aSig, &aExp, &aSig ); 4494 } 4495 aSig |= 0x00800000; 4496 return packFloatx80( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<40 ); 4497 4498 } 4499 4500 /*---------------------------------------------------------------------------- 4501 | Returns the result of converting the single-precision floating-point value 4502 | `a' to the double-precision floating-point format. The conversion is 4503 | performed according to the IEC/IEEE Standard for Binary Floating-Point 4504 | Arithmetic. 4505 *----------------------------------------------------------------------------*/ 4506 4507 float128 float32_to_float128(float32 a, float_status *status) 4508 { 4509 flag aSign; 4510 int aExp; 4511 uint32_t aSig; 4512 4513 a = float32_squash_input_denormal(a, status); 4514 aSig = extractFloat32Frac( a ); 4515 aExp = extractFloat32Exp( a ); 4516 aSign = extractFloat32Sign( a ); 4517 if ( aExp == 0xFF ) { 4518 if (aSig) { 4519 return commonNaNToFloat128(float32ToCommonNaN(a, status), status); 4520 } 4521 return packFloat128( aSign, 0x7FFF, 0, 0 ); 4522 } 4523 if ( aExp == 0 ) { 4524 if ( aSig == 0 ) return packFloat128( aSign, 0, 0, 0 ); 4525 normalizeFloat32Subnormal( aSig, &aExp, &aSig ); 4526 --aExp; 4527 } 4528 return packFloat128( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<25, 0 ); 4529 4530 } 4531 4532 /*---------------------------------------------------------------------------- 4533 | Returns the remainder of the single-precision floating-point value `a' 4534 | with respect to the corresponding value `b'. The operation is performed 4535 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4536 *----------------------------------------------------------------------------*/ 4537 4538 float32 float32_rem(float32 a, float32 b, float_status *status) 4539 { 4540 flag aSign, zSign; 4541 int aExp, bExp, expDiff; 4542 uint32_t aSig, bSig; 4543 uint32_t q; 4544 uint64_t aSig64, bSig64, q64; 4545 uint32_t alternateASig; 4546 int32_t sigMean; 4547 a = float32_squash_input_denormal(a, status); 4548 b = float32_squash_input_denormal(b, status); 4549 4550 aSig = extractFloat32Frac( a ); 4551 aExp = extractFloat32Exp( a ); 4552 aSign = extractFloat32Sign( a ); 4553 bSig = extractFloat32Frac( b ); 4554 bExp = extractFloat32Exp( b ); 4555 if ( aExp == 0xFF ) { 4556 if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) { 4557 return propagateFloat32NaN(a, b, status); 4558 } 4559 float_raise(float_flag_invalid, status); 4560 return float32_default_nan(status); 4561 } 4562 if ( bExp == 0xFF ) { 4563 if (bSig) { 4564 return propagateFloat32NaN(a, b, status); 4565 } 4566 return a; 4567 } 4568 if ( bExp == 0 ) { 4569 if ( bSig == 0 ) { 4570 float_raise(float_flag_invalid, status); 4571 return float32_default_nan(status); 4572 } 4573 normalizeFloat32Subnormal( bSig, &bExp, &bSig ); 4574 } 4575 if ( aExp == 0 ) { 4576 if ( aSig == 0 ) return a; 4577 normalizeFloat32Subnormal( aSig, &aExp, &aSig ); 4578 } 4579 expDiff = aExp - bExp; 4580 aSig |= 0x00800000; 4581 bSig |= 0x00800000; 4582 if ( expDiff < 32 ) { 4583 aSig <<= 8; 4584 bSig <<= 8; 4585 if ( expDiff < 0 ) { 4586 if ( expDiff < -1 ) return a; 4587 aSig >>= 1; 4588 } 4589 q = ( bSig <= aSig ); 4590 if ( q ) aSig -= bSig; 4591 if ( 0 < expDiff ) { 4592 q = ( ( (uint64_t) aSig )<<32 ) / bSig; 4593 q >>= 32 - expDiff; 4594 bSig >>= 2; 4595 aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q; 4596 } 4597 else { 4598 aSig >>= 2; 4599 bSig >>= 2; 4600 } 4601 } 4602 else { 4603 if ( bSig <= aSig ) aSig -= bSig; 4604 aSig64 = ( (uint64_t) aSig )<<40; 4605 bSig64 = ( (uint64_t) bSig )<<40; 4606 expDiff -= 64; 4607 while ( 0 < expDiff ) { 4608 q64 = estimateDiv128To64( aSig64, 0, bSig64 ); 4609 q64 = ( 2 < q64 ) ? q64 - 2 : 0; 4610 aSig64 = - ( ( bSig * q64 )<<38 ); 4611 expDiff -= 62; 4612 } 4613 expDiff += 64; 4614 q64 = estimateDiv128To64( aSig64, 0, bSig64 ); 4615 q64 = ( 2 < q64 ) ? q64 - 2 : 0; 4616 q = q64>>( 64 - expDiff ); 4617 bSig <<= 6; 4618 aSig = ( ( aSig64>>33 )<<( expDiff - 1 ) ) - bSig * q; 4619 } 4620 do { 4621 alternateASig = aSig; 4622 ++q; 4623 aSig -= bSig; 4624 } while ( 0 <= (int32_t) aSig ); 4625 sigMean = aSig + alternateASig; 4626 if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) { 4627 aSig = alternateASig; 4628 } 4629 zSign = ( (int32_t) aSig < 0 ); 4630 if ( zSign ) aSig = - aSig; 4631 return normalizeRoundAndPackFloat32(aSign ^ zSign, bExp, aSig, status); 4632 } 4633 4634 4635 4636 /*---------------------------------------------------------------------------- 4637 | Returns the binary exponential of the single-precision floating-point value 4638 | `a'. The operation is performed according to the IEC/IEEE Standard for 4639 | Binary Floating-Point Arithmetic. 4640 | 4641 | Uses the following identities: 4642 | 4643 | 1. ------------------------------------------------------------------------- 4644 | x x*ln(2) 4645 | 2 = e 4646 | 4647 | 2. ------------------------------------------------------------------------- 4648 | 2 3 4 5 n 4649 | x x x x x x x 4650 | e = 1 + --- + --- + --- + --- + --- + ... + --- + ... 4651 | 1! 2! 3! 4! 5! n! 4652 *----------------------------------------------------------------------------*/ 4653 4654 static const float64 float32_exp2_coefficients[15] = 4655 { 4656 const_float64( 0x3ff0000000000000ll ), /* 1 */ 4657 const_float64( 0x3fe0000000000000ll ), /* 2 */ 4658 const_float64( 0x3fc5555555555555ll ), /* 3 */ 4659 const_float64( 0x3fa5555555555555ll ), /* 4 */ 4660 const_float64( 0x3f81111111111111ll ), /* 5 */ 4661 const_float64( 0x3f56c16c16c16c17ll ), /* 6 */ 4662 const_float64( 0x3f2a01a01a01a01all ), /* 7 */ 4663 const_float64( 0x3efa01a01a01a01all ), /* 8 */ 4664 const_float64( 0x3ec71de3a556c734ll ), /* 9 */ 4665 const_float64( 0x3e927e4fb7789f5cll ), /* 10 */ 4666 const_float64( 0x3e5ae64567f544e4ll ), /* 11 */ 4667 const_float64( 0x3e21eed8eff8d898ll ), /* 12 */ 4668 const_float64( 0x3de6124613a86d09ll ), /* 13 */ 4669 const_float64( 0x3da93974a8c07c9dll ), /* 14 */ 4670 const_float64( 0x3d6ae7f3e733b81fll ), /* 15 */ 4671 }; 4672 4673 float32 float32_exp2(float32 a, float_status *status) 4674 { 4675 flag aSign; 4676 int aExp; 4677 uint32_t aSig; 4678 float64 r, x, xn; 4679 int i; 4680 a = float32_squash_input_denormal(a, status); 4681 4682 aSig = extractFloat32Frac( a ); 4683 aExp = extractFloat32Exp( a ); 4684 aSign = extractFloat32Sign( a ); 4685 4686 if ( aExp == 0xFF) { 4687 if (aSig) { 4688 return propagateFloat32NaN(a, float32_zero, status); 4689 } 4690 return (aSign) ? float32_zero : a; 4691 } 4692 if (aExp == 0) { 4693 if (aSig == 0) return float32_one; 4694 } 4695 4696 float_raise(float_flag_inexact, status); 4697 4698 /* ******************************* */ 4699 /* using float64 for approximation */ 4700 /* ******************************* */ 4701 x = float32_to_float64(a, status); 4702 x = float64_mul(x, float64_ln2, status); 4703 4704 xn = x; 4705 r = float64_one; 4706 for (i = 0 ; i < 15 ; i++) { 4707 float64 f; 4708 4709 f = float64_mul(xn, float32_exp2_coefficients[i], status); 4710 r = float64_add(r, f, status); 4711 4712 xn = float64_mul(xn, x, status); 4713 } 4714 4715 return float64_to_float32(r, status); 4716 } 4717 4718 /*---------------------------------------------------------------------------- 4719 | Returns the binary log of the single-precision floating-point value `a'. 4720 | The operation is performed according to the IEC/IEEE Standard for Binary 4721 | Floating-Point Arithmetic. 4722 *----------------------------------------------------------------------------*/ 4723 float32 float32_log2(float32 a, float_status *status) 4724 { 4725 flag aSign, zSign; 4726 int aExp; 4727 uint32_t aSig, zSig, i; 4728 4729 a = float32_squash_input_denormal(a, status); 4730 aSig = extractFloat32Frac( a ); 4731 aExp = extractFloat32Exp( a ); 4732 aSign = extractFloat32Sign( a ); 4733 4734 if ( aExp == 0 ) { 4735 if ( aSig == 0 ) return packFloat32( 1, 0xFF, 0 ); 4736 normalizeFloat32Subnormal( aSig, &aExp, &aSig ); 4737 } 4738 if ( aSign ) { 4739 float_raise(float_flag_invalid, status); 4740 return float32_default_nan(status); 4741 } 4742 if ( aExp == 0xFF ) { 4743 if (aSig) { 4744 return propagateFloat32NaN(a, float32_zero, status); 4745 } 4746 return a; 4747 } 4748 4749 aExp -= 0x7F; 4750 aSig |= 0x00800000; 4751 zSign = aExp < 0; 4752 zSig = aExp << 23; 4753 4754 for (i = 1 << 22; i > 0; i >>= 1) { 4755 aSig = ( (uint64_t)aSig * aSig ) >> 23; 4756 if ( aSig & 0x01000000 ) { 4757 aSig >>= 1; 4758 zSig |= i; 4759 } 4760 } 4761 4762 if ( zSign ) 4763 zSig = -zSig; 4764 4765 return normalizeRoundAndPackFloat32(zSign, 0x85, zSig, status); 4766 } 4767 4768 /*---------------------------------------------------------------------------- 4769 | Returns 1 if the single-precision floating-point value `a' is equal to 4770 | the corresponding value `b', and 0 otherwise. The invalid exception is 4771 | raised if either operand is a NaN. Otherwise, the comparison is performed 4772 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4773 *----------------------------------------------------------------------------*/ 4774 4775 int float32_eq(float32 a, float32 b, float_status *status) 4776 { 4777 uint32_t av, bv; 4778 a = float32_squash_input_denormal(a, status); 4779 b = float32_squash_input_denormal(b, status); 4780 4781 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4782 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4783 ) { 4784 float_raise(float_flag_invalid, status); 4785 return 0; 4786 } 4787 av = float32_val(a); 4788 bv = float32_val(b); 4789 return ( av == bv ) || ( (uint32_t) ( ( av | bv )<<1 ) == 0 ); 4790 } 4791 4792 /*---------------------------------------------------------------------------- 4793 | Returns 1 if the single-precision floating-point value `a' is less than 4794 | or equal to the corresponding value `b', and 0 otherwise. The invalid 4795 | exception is raised if either operand is a NaN. The comparison is performed 4796 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4797 *----------------------------------------------------------------------------*/ 4798 4799 int float32_le(float32 a, float32 b, float_status *status) 4800 { 4801 flag aSign, bSign; 4802 uint32_t av, bv; 4803 a = float32_squash_input_denormal(a, status); 4804 b = float32_squash_input_denormal(b, status); 4805 4806 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4807 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4808 ) { 4809 float_raise(float_flag_invalid, status); 4810 return 0; 4811 } 4812 aSign = extractFloat32Sign( a ); 4813 bSign = extractFloat32Sign( b ); 4814 av = float32_val(a); 4815 bv = float32_val(b); 4816 if ( aSign != bSign ) return aSign || ( (uint32_t) ( ( av | bv )<<1 ) == 0 ); 4817 return ( av == bv ) || ( aSign ^ ( av < bv ) ); 4818 4819 } 4820 4821 /*---------------------------------------------------------------------------- 4822 | Returns 1 if the single-precision floating-point value `a' is less than 4823 | the corresponding value `b', and 0 otherwise. The invalid exception is 4824 | raised if either operand is a NaN. The comparison is performed according 4825 | to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4826 *----------------------------------------------------------------------------*/ 4827 4828 int float32_lt(float32 a, float32 b, float_status *status) 4829 { 4830 flag aSign, bSign; 4831 uint32_t av, bv; 4832 a = float32_squash_input_denormal(a, status); 4833 b = float32_squash_input_denormal(b, status); 4834 4835 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4836 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4837 ) { 4838 float_raise(float_flag_invalid, status); 4839 return 0; 4840 } 4841 aSign = extractFloat32Sign( a ); 4842 bSign = extractFloat32Sign( b ); 4843 av = float32_val(a); 4844 bv = float32_val(b); 4845 if ( aSign != bSign ) return aSign && ( (uint32_t) ( ( av | bv )<<1 ) != 0 ); 4846 return ( av != bv ) && ( aSign ^ ( av < bv ) ); 4847 4848 } 4849 4850 /*---------------------------------------------------------------------------- 4851 | Returns 1 if the single-precision floating-point values `a' and `b' cannot 4852 | be compared, and 0 otherwise. The invalid exception is raised if either 4853 | operand is a NaN. The comparison is performed according to the IEC/IEEE 4854 | Standard for Binary Floating-Point Arithmetic. 4855 *----------------------------------------------------------------------------*/ 4856 4857 int float32_unordered(float32 a, float32 b, float_status *status) 4858 { 4859 a = float32_squash_input_denormal(a, status); 4860 b = float32_squash_input_denormal(b, status); 4861 4862 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4863 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4864 ) { 4865 float_raise(float_flag_invalid, status); 4866 return 1; 4867 } 4868 return 0; 4869 } 4870 4871 /*---------------------------------------------------------------------------- 4872 | Returns 1 if the single-precision floating-point value `a' is equal to 4873 | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an 4874 | exception. The comparison is performed according to the IEC/IEEE Standard 4875 | for Binary Floating-Point Arithmetic. 4876 *----------------------------------------------------------------------------*/ 4877 4878 int float32_eq_quiet(float32 a, float32 b, float_status *status) 4879 { 4880 a = float32_squash_input_denormal(a, status); 4881 b = float32_squash_input_denormal(b, status); 4882 4883 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4884 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4885 ) { 4886 if (float32_is_signaling_nan(a, status) 4887 || float32_is_signaling_nan(b, status)) { 4888 float_raise(float_flag_invalid, status); 4889 } 4890 return 0; 4891 } 4892 return ( float32_val(a) == float32_val(b) ) || 4893 ( (uint32_t) ( ( float32_val(a) | float32_val(b) )<<1 ) == 0 ); 4894 } 4895 4896 /*---------------------------------------------------------------------------- 4897 | Returns 1 if the single-precision floating-point value `a' is less than or 4898 | equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not 4899 | cause an exception. Otherwise, the comparison is performed according to the 4900 | IEC/IEEE Standard for Binary Floating-Point Arithmetic. 4901 *----------------------------------------------------------------------------*/ 4902 4903 int float32_le_quiet(float32 a, float32 b, float_status *status) 4904 { 4905 flag aSign, bSign; 4906 uint32_t av, bv; 4907 a = float32_squash_input_denormal(a, status); 4908 b = float32_squash_input_denormal(b, status); 4909 4910 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4911 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4912 ) { 4913 if (float32_is_signaling_nan(a, status) 4914 || float32_is_signaling_nan(b, status)) { 4915 float_raise(float_flag_invalid, status); 4916 } 4917 return 0; 4918 } 4919 aSign = extractFloat32Sign( a ); 4920 bSign = extractFloat32Sign( b ); 4921 av = float32_val(a); 4922 bv = float32_val(b); 4923 if ( aSign != bSign ) return aSign || ( (uint32_t) ( ( av | bv )<<1 ) == 0 ); 4924 return ( av == bv ) || ( aSign ^ ( av < bv ) ); 4925 4926 } 4927 4928 /*---------------------------------------------------------------------------- 4929 | Returns 1 if the single-precision floating-point value `a' is less than 4930 | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an 4931 | exception. Otherwise, the comparison is performed according to the IEC/IEEE 4932 | Standard for Binary Floating-Point Arithmetic. 4933 *----------------------------------------------------------------------------*/ 4934 4935 int float32_lt_quiet(float32 a, float32 b, float_status *status) 4936 { 4937 flag aSign, bSign; 4938 uint32_t av, bv; 4939 a = float32_squash_input_denormal(a, status); 4940 b = float32_squash_input_denormal(b, status); 4941 4942 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4943 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4944 ) { 4945 if (float32_is_signaling_nan(a, status) 4946 || float32_is_signaling_nan(b, status)) { 4947 float_raise(float_flag_invalid, status); 4948 } 4949 return 0; 4950 } 4951 aSign = extractFloat32Sign( a ); 4952 bSign = extractFloat32Sign( b ); 4953 av = float32_val(a); 4954 bv = float32_val(b); 4955 if ( aSign != bSign ) return aSign && ( (uint32_t) ( ( av | bv )<<1 ) != 0 ); 4956 return ( av != bv ) && ( aSign ^ ( av < bv ) ); 4957 4958 } 4959 4960 /*---------------------------------------------------------------------------- 4961 | Returns 1 if the single-precision floating-point values `a' and `b' cannot 4962 | be compared, and 0 otherwise. Quiet NaNs do not cause an exception. The 4963 | comparison is performed according to the IEC/IEEE Standard for Binary 4964 | Floating-Point Arithmetic. 4965 *----------------------------------------------------------------------------*/ 4966 4967 int float32_unordered_quiet(float32 a, float32 b, float_status *status) 4968 { 4969 a = float32_squash_input_denormal(a, status); 4970 b = float32_squash_input_denormal(b, status); 4971 4972 if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) 4973 || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) 4974 ) { 4975 if (float32_is_signaling_nan(a, status) 4976 || float32_is_signaling_nan(b, status)) { 4977 float_raise(float_flag_invalid, status); 4978 } 4979 return 1; 4980 } 4981 return 0; 4982 } 4983 4984 /*---------------------------------------------------------------------------- 4985 | If `a' is denormal and we are in flush-to-zero mode then set the 4986 | input-denormal exception and return zero. Otherwise just return the value. 4987 *----------------------------------------------------------------------------*/ 4988 float16 float16_squash_input_denormal(float16 a, float_status *status) 4989 { 4990 if (status->flush_inputs_to_zero) { 4991 if (extractFloat16Exp(a) == 0 && extractFloat16Frac(a) != 0) { 4992 float_raise(float_flag_input_denormal, status); 4993 return make_float16(float16_val(a) & 0x8000); 4994 } 4995 } 4996 return a; 4997 } 4998 4999 /*---------------------------------------------------------------------------- 5000 | Returns the result of converting the double-precision floating-point value 5001 | `a' to the extended double-precision floating-point format. The conversion 5002 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 5003 | Arithmetic. 5004 *----------------------------------------------------------------------------*/ 5005 5006 floatx80 float64_to_floatx80(float64 a, float_status *status) 5007 { 5008 flag aSign; 5009 int aExp; 5010 uint64_t aSig; 5011 5012 a = float64_squash_input_denormal(a, status); 5013 aSig = extractFloat64Frac( a ); 5014 aExp = extractFloat64Exp( a ); 5015 aSign = extractFloat64Sign( a ); 5016 if ( aExp == 0x7FF ) { 5017 if (aSig) { 5018 return commonNaNToFloatx80(float64ToCommonNaN(a, status), status); 5019 } 5020 return packFloatx80(aSign, 5021 floatx80_infinity_high, 5022 floatx80_infinity_low); 5023 } 5024 if ( aExp == 0 ) { 5025 if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 ); 5026 normalizeFloat64Subnormal( aSig, &aExp, &aSig ); 5027 } 5028 return 5029 packFloatx80( 5030 aSign, aExp + 0x3C00, ( aSig | LIT64( 0x0010000000000000 ) )<<11 ); 5031 5032 } 5033 5034 /*---------------------------------------------------------------------------- 5035 | Returns the result of converting the double-precision floating-point value 5036 | `a' to the quadruple-precision floating-point format. The conversion is 5037 | performed according to the IEC/IEEE Standard for Binary Floating-Point 5038 | Arithmetic. 5039 *----------------------------------------------------------------------------*/ 5040 5041 float128 float64_to_float128(float64 a, float_status *status) 5042 { 5043 flag aSign; 5044 int aExp; 5045 uint64_t aSig, zSig0, zSig1; 5046 5047 a = float64_squash_input_denormal(a, status); 5048 aSig = extractFloat64Frac( a ); 5049 aExp = extractFloat64Exp( a ); 5050 aSign = extractFloat64Sign( a ); 5051 if ( aExp == 0x7FF ) { 5052 if (aSig) { 5053 return commonNaNToFloat128(float64ToCommonNaN(a, status), status); 5054 } 5055 return packFloat128( aSign, 0x7FFF, 0, 0 ); 5056 } 5057 if ( aExp == 0 ) { 5058 if ( aSig == 0 ) return packFloat128( aSign, 0, 0, 0 ); 5059 normalizeFloat64Subnormal( aSig, &aExp, &aSig ); 5060 --aExp; 5061 } 5062 shift128Right( aSig, 0, 4, &zSig0, &zSig1 ); 5063 return packFloat128( aSign, aExp + 0x3C00, zSig0, zSig1 ); 5064 5065 } 5066 5067 5068 /*---------------------------------------------------------------------------- 5069 | Returns the remainder of the double-precision floating-point value `a' 5070 | with respect to the corresponding value `b'. The operation is performed 5071 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 5072 *----------------------------------------------------------------------------*/ 5073 5074 float64 float64_rem(float64 a, float64 b, float_status *status) 5075 { 5076 flag aSign, zSign; 5077 int aExp, bExp, expDiff; 5078 uint64_t aSig, bSig; 5079 uint64_t q, alternateASig; 5080 int64_t sigMean; 5081 5082 a = float64_squash_input_denormal(a, status); 5083 b = float64_squash_input_denormal(b, status); 5084 aSig = extractFloat64Frac( a ); 5085 aExp = extractFloat64Exp( a ); 5086 aSign = extractFloat64Sign( a ); 5087 bSig = extractFloat64Frac( b ); 5088 bExp = extractFloat64Exp( b ); 5089 if ( aExp == 0x7FF ) { 5090 if ( aSig || ( ( bExp == 0x7FF ) && bSig ) ) { 5091 return propagateFloat64NaN(a, b, status); 5092 } 5093 float_raise(float_flag_invalid, status); 5094 return float64_default_nan(status); 5095 } 5096 if ( bExp == 0x7FF ) { 5097 if (bSig) { 5098 return propagateFloat64NaN(a, b, status); 5099 } 5100 return a; 5101 } 5102 if ( bExp == 0 ) { 5103 if ( bSig == 0 ) { 5104 float_raise(float_flag_invalid, status); 5105 return float64_default_nan(status); 5106 } 5107 normalizeFloat64Subnormal( bSig, &bExp, &bSig ); 5108 } 5109 if ( aExp == 0 ) { 5110 if ( aSig == 0 ) return a; 5111 normalizeFloat64Subnormal( aSig, &aExp, &aSig ); 5112 } 5113 expDiff = aExp - bExp; 5114 aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<11; 5115 bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11; 5116 if ( expDiff < 0 ) { 5117 if ( expDiff < -1 ) return a; 5118 aSig >>= 1; 5119 } 5120 q = ( bSig <= aSig ); 5121 if ( q ) aSig -= bSig; 5122 expDiff -= 64; 5123 while ( 0 < expDiff ) { 5124 q = estimateDiv128To64( aSig, 0, bSig ); 5125 q = ( 2 < q ) ? q - 2 : 0; 5126 aSig = - ( ( bSig>>2 ) * q ); 5127 expDiff -= 62; 5128 } 5129 expDiff += 64; 5130 if ( 0 < expDiff ) { 5131 q = estimateDiv128To64( aSig, 0, bSig ); 5132 q = ( 2 < q ) ? q - 2 : 0; 5133 q >>= 64 - expDiff; 5134 bSig >>= 2; 5135 aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q; 5136 } 5137 else { 5138 aSig >>= 2; 5139 bSig >>= 2; 5140 } 5141 do { 5142 alternateASig = aSig; 5143 ++q; 5144 aSig -= bSig; 5145 } while ( 0 <= (int64_t) aSig ); 5146 sigMean = aSig + alternateASig; 5147 if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) { 5148 aSig = alternateASig; 5149 } 5150 zSign = ( (int64_t) aSig < 0 ); 5151 if ( zSign ) aSig = - aSig; 5152 return normalizeRoundAndPackFloat64(aSign ^ zSign, bExp, aSig, status); 5153 5154 } 5155 5156 /*---------------------------------------------------------------------------- 5157 | Returns the binary log of the double-precision floating-point value `a'. 5158 | The operation is performed according to the IEC/IEEE Standard for Binary 5159 | Floating-Point Arithmetic. 5160 *----------------------------------------------------------------------------*/ 5161 float64 float64_log2(float64 a, float_status *status) 5162 { 5163 flag aSign, zSign; 5164 int aExp; 5165 uint64_t aSig, aSig0, aSig1, zSig, i; 5166 a = float64_squash_input_denormal(a, status); 5167 5168 aSig = extractFloat64Frac( a ); 5169 aExp = extractFloat64Exp( a ); 5170 aSign = extractFloat64Sign( a ); 5171 5172 if ( aExp == 0 ) { 5173 if ( aSig == 0 ) return packFloat64( 1, 0x7FF, 0 ); 5174 normalizeFloat64Subnormal( aSig, &aExp, &aSig ); 5175 } 5176 if ( aSign ) { 5177 float_raise(float_flag_invalid, status); 5178 return float64_default_nan(status); 5179 } 5180 if ( aExp == 0x7FF ) { 5181 if (aSig) { 5182 return propagateFloat64NaN(a, float64_zero, status); 5183 } 5184 return a; 5185 } 5186 5187 aExp -= 0x3FF; 5188 aSig |= LIT64( 0x0010000000000000 ); 5189 zSign = aExp < 0; 5190 zSig = (uint64_t)aExp << 52; 5191 for (i = 1LL << 51; i > 0; i >>= 1) { 5192 mul64To128( aSig, aSig, &aSig0, &aSig1 ); 5193 aSig = ( aSig0 << 12 ) | ( aSig1 >> 52 ); 5194 if ( aSig & LIT64( 0x0020000000000000 ) ) { 5195 aSig >>= 1; 5196 zSig |= i; 5197 } 5198 } 5199 5200 if ( zSign ) 5201 zSig = -zSig; 5202 return normalizeRoundAndPackFloat64(zSign, 0x408, zSig, status); 5203 } 5204 5205 /*---------------------------------------------------------------------------- 5206 | Returns 1 if the double-precision floating-point value `a' is equal to the 5207 | corresponding value `b', and 0 otherwise. The invalid exception is raised 5208 | if either operand is a NaN. Otherwise, the comparison is performed 5209 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 5210 *----------------------------------------------------------------------------*/ 5211 5212 int float64_eq(float64 a, float64 b, float_status *status) 5213 { 5214 uint64_t av, bv; 5215 a = float64_squash_input_denormal(a, status); 5216 b = float64_squash_input_denormal(b, status); 5217 5218 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5219 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5220 ) { 5221 float_raise(float_flag_invalid, status); 5222 return 0; 5223 } 5224 av = float64_val(a); 5225 bv = float64_val(b); 5226 return ( av == bv ) || ( (uint64_t) ( ( av | bv )<<1 ) == 0 ); 5227 5228 } 5229 5230 /*---------------------------------------------------------------------------- 5231 | Returns 1 if the double-precision floating-point value `a' is less than or 5232 | equal to the corresponding value `b', and 0 otherwise. The invalid 5233 | exception is raised if either operand is a NaN. The comparison is performed 5234 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 5235 *----------------------------------------------------------------------------*/ 5236 5237 int float64_le(float64 a, float64 b, float_status *status) 5238 { 5239 flag aSign, bSign; 5240 uint64_t av, bv; 5241 a = float64_squash_input_denormal(a, status); 5242 b = float64_squash_input_denormal(b, status); 5243 5244 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5245 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5246 ) { 5247 float_raise(float_flag_invalid, status); 5248 return 0; 5249 } 5250 aSign = extractFloat64Sign( a ); 5251 bSign = extractFloat64Sign( b ); 5252 av = float64_val(a); 5253 bv = float64_val(b); 5254 if ( aSign != bSign ) return aSign || ( (uint64_t) ( ( av | bv )<<1 ) == 0 ); 5255 return ( av == bv ) || ( aSign ^ ( av < bv ) ); 5256 5257 } 5258 5259 /*---------------------------------------------------------------------------- 5260 | Returns 1 if the double-precision floating-point value `a' is less than 5261 | the corresponding value `b', and 0 otherwise. The invalid exception is 5262 | raised if either operand is a NaN. The comparison is performed according 5263 | to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 5264 *----------------------------------------------------------------------------*/ 5265 5266 int float64_lt(float64 a, float64 b, float_status *status) 5267 { 5268 flag aSign, bSign; 5269 uint64_t av, bv; 5270 5271 a = float64_squash_input_denormal(a, status); 5272 b = float64_squash_input_denormal(b, status); 5273 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5274 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5275 ) { 5276 float_raise(float_flag_invalid, status); 5277 return 0; 5278 } 5279 aSign = extractFloat64Sign( a ); 5280 bSign = extractFloat64Sign( b ); 5281 av = float64_val(a); 5282 bv = float64_val(b); 5283 if ( aSign != bSign ) return aSign && ( (uint64_t) ( ( av | bv )<<1 ) != 0 ); 5284 return ( av != bv ) && ( aSign ^ ( av < bv ) ); 5285 5286 } 5287 5288 /*---------------------------------------------------------------------------- 5289 | Returns 1 if the double-precision floating-point values `a' and `b' cannot 5290 | be compared, and 0 otherwise. The invalid exception is raised if either 5291 | operand is a NaN. The comparison is performed according to the IEC/IEEE 5292 | Standard for Binary Floating-Point Arithmetic. 5293 *----------------------------------------------------------------------------*/ 5294 5295 int float64_unordered(float64 a, float64 b, float_status *status) 5296 { 5297 a = float64_squash_input_denormal(a, status); 5298 b = float64_squash_input_denormal(b, status); 5299 5300 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5301 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5302 ) { 5303 float_raise(float_flag_invalid, status); 5304 return 1; 5305 } 5306 return 0; 5307 } 5308 5309 /*---------------------------------------------------------------------------- 5310 | Returns 1 if the double-precision floating-point value `a' is equal to the 5311 | corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an 5312 | exception.The comparison is performed according to the IEC/IEEE Standard 5313 | for Binary Floating-Point Arithmetic. 5314 *----------------------------------------------------------------------------*/ 5315 5316 int float64_eq_quiet(float64 a, float64 b, float_status *status) 5317 { 5318 uint64_t av, bv; 5319 a = float64_squash_input_denormal(a, status); 5320 b = float64_squash_input_denormal(b, status); 5321 5322 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5323 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5324 ) { 5325 if (float64_is_signaling_nan(a, status) 5326 || float64_is_signaling_nan(b, status)) { 5327 float_raise(float_flag_invalid, status); 5328 } 5329 return 0; 5330 } 5331 av = float64_val(a); 5332 bv = float64_val(b); 5333 return ( av == bv ) || ( (uint64_t) ( ( av | bv )<<1 ) == 0 ); 5334 5335 } 5336 5337 /*---------------------------------------------------------------------------- 5338 | Returns 1 if the double-precision floating-point value `a' is less than or 5339 | equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not 5340 | cause an exception. Otherwise, the comparison is performed according to the 5341 | IEC/IEEE Standard for Binary Floating-Point Arithmetic. 5342 *----------------------------------------------------------------------------*/ 5343 5344 int float64_le_quiet(float64 a, float64 b, float_status *status) 5345 { 5346 flag aSign, bSign; 5347 uint64_t av, bv; 5348 a = float64_squash_input_denormal(a, status); 5349 b = float64_squash_input_denormal(b, status); 5350 5351 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5352 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5353 ) { 5354 if (float64_is_signaling_nan(a, status) 5355 || float64_is_signaling_nan(b, status)) { 5356 float_raise(float_flag_invalid, status); 5357 } 5358 return 0; 5359 } 5360 aSign = extractFloat64Sign( a ); 5361 bSign = extractFloat64Sign( b ); 5362 av = float64_val(a); 5363 bv = float64_val(b); 5364 if ( aSign != bSign ) return aSign || ( (uint64_t) ( ( av | bv )<<1 ) == 0 ); 5365 return ( av == bv ) || ( aSign ^ ( av < bv ) ); 5366 5367 } 5368 5369 /*---------------------------------------------------------------------------- 5370 | Returns 1 if the double-precision floating-point value `a' is less than 5371 | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an 5372 | exception. Otherwise, the comparison is performed according to the IEC/IEEE 5373 | Standard for Binary Floating-Point Arithmetic. 5374 *----------------------------------------------------------------------------*/ 5375 5376 int float64_lt_quiet(float64 a, float64 b, float_status *status) 5377 { 5378 flag aSign, bSign; 5379 uint64_t av, bv; 5380 a = float64_squash_input_denormal(a, status); 5381 b = float64_squash_input_denormal(b, status); 5382 5383 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5384 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5385 ) { 5386 if (float64_is_signaling_nan(a, status) 5387 || float64_is_signaling_nan(b, status)) { 5388 float_raise(float_flag_invalid, status); 5389 } 5390 return 0; 5391 } 5392 aSign = extractFloat64Sign( a ); 5393 bSign = extractFloat64Sign( b ); 5394 av = float64_val(a); 5395 bv = float64_val(b); 5396 if ( aSign != bSign ) return aSign && ( (uint64_t) ( ( av | bv )<<1 ) != 0 ); 5397 return ( av != bv ) && ( aSign ^ ( av < bv ) ); 5398 5399 } 5400 5401 /*---------------------------------------------------------------------------- 5402 | Returns 1 if the double-precision floating-point values `a' and `b' cannot 5403 | be compared, and 0 otherwise. Quiet NaNs do not cause an exception. The 5404 | comparison is performed according to the IEC/IEEE Standard for Binary 5405 | Floating-Point Arithmetic. 5406 *----------------------------------------------------------------------------*/ 5407 5408 int float64_unordered_quiet(float64 a, float64 b, float_status *status) 5409 { 5410 a = float64_squash_input_denormal(a, status); 5411 b = float64_squash_input_denormal(b, status); 5412 5413 if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) 5414 || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) 5415 ) { 5416 if (float64_is_signaling_nan(a, status) 5417 || float64_is_signaling_nan(b, status)) { 5418 float_raise(float_flag_invalid, status); 5419 } 5420 return 1; 5421 } 5422 return 0; 5423 } 5424 5425 /*---------------------------------------------------------------------------- 5426 | Returns the result of converting the extended double-precision floating- 5427 | point value `a' to the 32-bit two's complement integer format. The 5428 | conversion is performed according to the IEC/IEEE Standard for Binary 5429 | Floating-Point Arithmetic---which means in particular that the conversion 5430 | is rounded according to the current rounding mode. If `a' is a NaN, the 5431 | largest positive integer is returned. Otherwise, if the conversion 5432 | overflows, the largest integer with the same sign as `a' is returned. 5433 *----------------------------------------------------------------------------*/ 5434 5435 int32_t floatx80_to_int32(floatx80 a, float_status *status) 5436 { 5437 flag aSign; 5438 int32_t aExp, shiftCount; 5439 uint64_t aSig; 5440 5441 if (floatx80_invalid_encoding(a)) { 5442 float_raise(float_flag_invalid, status); 5443 return 1 << 31; 5444 } 5445 aSig = extractFloatx80Frac( a ); 5446 aExp = extractFloatx80Exp( a ); 5447 aSign = extractFloatx80Sign( a ); 5448 if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) aSign = 0; 5449 shiftCount = 0x4037 - aExp; 5450 if ( shiftCount <= 0 ) shiftCount = 1; 5451 shift64RightJamming( aSig, shiftCount, &aSig ); 5452 return roundAndPackInt32(aSign, aSig, status); 5453 5454 } 5455 5456 /*---------------------------------------------------------------------------- 5457 | Returns the result of converting the extended double-precision floating- 5458 | point value `a' to the 32-bit two's complement integer format. The 5459 | conversion is performed according to the IEC/IEEE Standard for Binary 5460 | Floating-Point Arithmetic, except that the conversion is always rounded 5461 | toward zero. If `a' is a NaN, the largest positive integer is returned. 5462 | Otherwise, if the conversion overflows, the largest integer with the same 5463 | sign as `a' is returned. 5464 *----------------------------------------------------------------------------*/ 5465 5466 int32_t floatx80_to_int32_round_to_zero(floatx80 a, float_status *status) 5467 { 5468 flag aSign; 5469 int32_t aExp, shiftCount; 5470 uint64_t aSig, savedASig; 5471 int32_t z; 5472 5473 if (floatx80_invalid_encoding(a)) { 5474 float_raise(float_flag_invalid, status); 5475 return 1 << 31; 5476 } 5477 aSig = extractFloatx80Frac( a ); 5478 aExp = extractFloatx80Exp( a ); 5479 aSign = extractFloatx80Sign( a ); 5480 if ( 0x401E < aExp ) { 5481 if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) aSign = 0; 5482 goto invalid; 5483 } 5484 else if ( aExp < 0x3FFF ) { 5485 if (aExp || aSig) { 5486 status->float_exception_flags |= float_flag_inexact; 5487 } 5488 return 0; 5489 } 5490 shiftCount = 0x403E - aExp; 5491 savedASig = aSig; 5492 aSig >>= shiftCount; 5493 z = aSig; 5494 if ( aSign ) z = - z; 5495 if ( ( z < 0 ) ^ aSign ) { 5496 invalid: 5497 float_raise(float_flag_invalid, status); 5498 return aSign ? (int32_t) 0x80000000 : 0x7FFFFFFF; 5499 } 5500 if ( ( aSig<<shiftCount ) != savedASig ) { 5501 status->float_exception_flags |= float_flag_inexact; 5502 } 5503 return z; 5504 5505 } 5506 5507 /*---------------------------------------------------------------------------- 5508 | Returns the result of converting the extended double-precision floating- 5509 | point value `a' to the 64-bit two's complement integer format. The 5510 | conversion is performed according to the IEC/IEEE Standard for Binary 5511 | Floating-Point Arithmetic---which means in particular that the conversion 5512 | is rounded according to the current rounding mode. If `a' is a NaN, 5513 | the largest positive integer is returned. Otherwise, if the conversion 5514 | overflows, the largest integer with the same sign as `a' is returned. 5515 *----------------------------------------------------------------------------*/ 5516 5517 int64_t floatx80_to_int64(floatx80 a, float_status *status) 5518 { 5519 flag aSign; 5520 int32_t aExp, shiftCount; 5521 uint64_t aSig, aSigExtra; 5522 5523 if (floatx80_invalid_encoding(a)) { 5524 float_raise(float_flag_invalid, status); 5525 return 1ULL << 63; 5526 } 5527 aSig = extractFloatx80Frac( a ); 5528 aExp = extractFloatx80Exp( a ); 5529 aSign = extractFloatx80Sign( a ); 5530 shiftCount = 0x403E - aExp; 5531 if ( shiftCount <= 0 ) { 5532 if ( shiftCount ) { 5533 float_raise(float_flag_invalid, status); 5534 if (!aSign || floatx80_is_any_nan(a)) { 5535 return LIT64( 0x7FFFFFFFFFFFFFFF ); 5536 } 5537 return (int64_t) LIT64( 0x8000000000000000 ); 5538 } 5539 aSigExtra = 0; 5540 } 5541 else { 5542 shift64ExtraRightJamming( aSig, 0, shiftCount, &aSig, &aSigExtra ); 5543 } 5544 return roundAndPackInt64(aSign, aSig, aSigExtra, status); 5545 5546 } 5547 5548 /*---------------------------------------------------------------------------- 5549 | Returns the result of converting the extended double-precision floating- 5550 | point value `a' to the 64-bit two's complement integer format. The 5551 | conversion is performed according to the IEC/IEEE Standard for Binary 5552 | Floating-Point Arithmetic, except that the conversion is always rounded 5553 | toward zero. If `a' is a NaN, the largest positive integer is returned. 5554 | Otherwise, if the conversion overflows, the largest integer with the same 5555 | sign as `a' is returned. 5556 *----------------------------------------------------------------------------*/ 5557 5558 int64_t floatx80_to_int64_round_to_zero(floatx80 a, float_status *status) 5559 { 5560 flag aSign; 5561 int32_t aExp, shiftCount; 5562 uint64_t aSig; 5563 int64_t z; 5564 5565 if (floatx80_invalid_encoding(a)) { 5566 float_raise(float_flag_invalid, status); 5567 return 1ULL << 63; 5568 } 5569 aSig = extractFloatx80Frac( a ); 5570 aExp = extractFloatx80Exp( a ); 5571 aSign = extractFloatx80Sign( a ); 5572 shiftCount = aExp - 0x403E; 5573 if ( 0 <= shiftCount ) { 5574 aSig &= LIT64( 0x7FFFFFFFFFFFFFFF ); 5575 if ( ( a.high != 0xC03E ) || aSig ) { 5576 float_raise(float_flag_invalid, status); 5577 if ( ! aSign || ( ( aExp == 0x7FFF ) && aSig ) ) { 5578 return LIT64( 0x7FFFFFFFFFFFFFFF ); 5579 } 5580 } 5581 return (int64_t) LIT64( 0x8000000000000000 ); 5582 } 5583 else if ( aExp < 0x3FFF ) { 5584 if (aExp | aSig) { 5585 status->float_exception_flags |= float_flag_inexact; 5586 } 5587 return 0; 5588 } 5589 z = aSig>>( - shiftCount ); 5590 if ( (uint64_t) ( aSig<<( shiftCount & 63 ) ) ) { 5591 status->float_exception_flags |= float_flag_inexact; 5592 } 5593 if ( aSign ) z = - z; 5594 return z; 5595 5596 } 5597 5598 /*---------------------------------------------------------------------------- 5599 | Returns the result of converting the extended double-precision floating- 5600 | point value `a' to the single-precision floating-point format. The 5601 | conversion is performed according to the IEC/IEEE Standard for Binary 5602 | Floating-Point Arithmetic. 5603 *----------------------------------------------------------------------------*/ 5604 5605 float32 floatx80_to_float32(floatx80 a, float_status *status) 5606 { 5607 flag aSign; 5608 int32_t aExp; 5609 uint64_t aSig; 5610 5611 if (floatx80_invalid_encoding(a)) { 5612 float_raise(float_flag_invalid, status); 5613 return float32_default_nan(status); 5614 } 5615 aSig = extractFloatx80Frac( a ); 5616 aExp = extractFloatx80Exp( a ); 5617 aSign = extractFloatx80Sign( a ); 5618 if ( aExp == 0x7FFF ) { 5619 if ( (uint64_t) ( aSig<<1 ) ) { 5620 return commonNaNToFloat32(floatx80ToCommonNaN(a, status), status); 5621 } 5622 return packFloat32( aSign, 0xFF, 0 ); 5623 } 5624 shift64RightJamming( aSig, 33, &aSig ); 5625 if ( aExp || aSig ) aExp -= 0x3F81; 5626 return roundAndPackFloat32(aSign, aExp, aSig, status); 5627 5628 } 5629 5630 /*---------------------------------------------------------------------------- 5631 | Returns the result of converting the extended double-precision floating- 5632 | point value `a' to the double-precision floating-point format. The 5633 | conversion is performed according to the IEC/IEEE Standard for Binary 5634 | Floating-Point Arithmetic. 5635 *----------------------------------------------------------------------------*/ 5636 5637 float64 floatx80_to_float64(floatx80 a, float_status *status) 5638 { 5639 flag aSign; 5640 int32_t aExp; 5641 uint64_t aSig, zSig; 5642 5643 if (floatx80_invalid_encoding(a)) { 5644 float_raise(float_flag_invalid, status); 5645 return float64_default_nan(status); 5646 } 5647 aSig = extractFloatx80Frac( a ); 5648 aExp = extractFloatx80Exp( a ); 5649 aSign = extractFloatx80Sign( a ); 5650 if ( aExp == 0x7FFF ) { 5651 if ( (uint64_t) ( aSig<<1 ) ) { 5652 return commonNaNToFloat64(floatx80ToCommonNaN(a, status), status); 5653 } 5654 return packFloat64( aSign, 0x7FF, 0 ); 5655 } 5656 shift64RightJamming( aSig, 1, &zSig ); 5657 if ( aExp || aSig ) aExp -= 0x3C01; 5658 return roundAndPackFloat64(aSign, aExp, zSig, status); 5659 5660 } 5661 5662 /*---------------------------------------------------------------------------- 5663 | Returns the result of converting the extended double-precision floating- 5664 | point value `a' to the quadruple-precision floating-point format. The 5665 | conversion is performed according to the IEC/IEEE Standard for Binary 5666 | Floating-Point Arithmetic. 5667 *----------------------------------------------------------------------------*/ 5668 5669 float128 floatx80_to_float128(floatx80 a, float_status *status) 5670 { 5671 flag aSign; 5672 int aExp; 5673 uint64_t aSig, zSig0, zSig1; 5674 5675 if (floatx80_invalid_encoding(a)) { 5676 float_raise(float_flag_invalid, status); 5677 return float128_default_nan(status); 5678 } 5679 aSig = extractFloatx80Frac( a ); 5680 aExp = extractFloatx80Exp( a ); 5681 aSign = extractFloatx80Sign( a ); 5682 if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) { 5683 return commonNaNToFloat128(floatx80ToCommonNaN(a, status), status); 5684 } 5685 shift128Right( aSig<<1, 0, 16, &zSig0, &zSig1 ); 5686 return packFloat128( aSign, aExp, zSig0, zSig1 ); 5687 5688 } 5689 5690 /*---------------------------------------------------------------------------- 5691 | Rounds the extended double-precision floating-point value `a' 5692 | to the precision provided by floatx80_rounding_precision and returns the 5693 | result as an extended double-precision floating-point value. 5694 | The operation is performed according to the IEC/IEEE Standard for Binary 5695 | Floating-Point Arithmetic. 5696 *----------------------------------------------------------------------------*/ 5697 5698 floatx80 floatx80_round(floatx80 a, float_status *status) 5699 { 5700 return roundAndPackFloatx80(status->floatx80_rounding_precision, 5701 extractFloatx80Sign(a), 5702 extractFloatx80Exp(a), 5703 extractFloatx80Frac(a), 0, status); 5704 } 5705 5706 /*---------------------------------------------------------------------------- 5707 | Rounds the extended double-precision floating-point value `a' to an integer, 5708 | and returns the result as an extended quadruple-precision floating-point 5709 | value. The operation is performed according to the IEC/IEEE Standard for 5710 | Binary Floating-Point Arithmetic. 5711 *----------------------------------------------------------------------------*/ 5712 5713 floatx80 floatx80_round_to_int(floatx80 a, float_status *status) 5714 { 5715 flag aSign; 5716 int32_t aExp; 5717 uint64_t lastBitMask, roundBitsMask; 5718 floatx80 z; 5719 5720 if (floatx80_invalid_encoding(a)) { 5721 float_raise(float_flag_invalid, status); 5722 return floatx80_default_nan(status); 5723 } 5724 aExp = extractFloatx80Exp( a ); 5725 if ( 0x403E <= aExp ) { 5726 if ( ( aExp == 0x7FFF ) && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) { 5727 return propagateFloatx80NaN(a, a, status); 5728 } 5729 return a; 5730 } 5731 if ( aExp < 0x3FFF ) { 5732 if ( ( aExp == 0 ) 5733 && ( (uint64_t) ( extractFloatx80Frac( a )<<1 ) == 0 ) ) { 5734 return a; 5735 } 5736 status->float_exception_flags |= float_flag_inexact; 5737 aSign = extractFloatx80Sign( a ); 5738 switch (status->float_rounding_mode) { 5739 case float_round_nearest_even: 5740 if ( ( aExp == 0x3FFE ) && (uint64_t) ( extractFloatx80Frac( a )<<1 ) 5741 ) { 5742 return 5743 packFloatx80( aSign, 0x3FFF, LIT64( 0x8000000000000000 ) ); 5744 } 5745 break; 5746 case float_round_ties_away: 5747 if (aExp == 0x3FFE) { 5748 return packFloatx80(aSign, 0x3FFF, LIT64(0x8000000000000000)); 5749 } 5750 break; 5751 case float_round_down: 5752 return 5753 aSign ? 5754 packFloatx80( 1, 0x3FFF, LIT64( 0x8000000000000000 ) ) 5755 : packFloatx80( 0, 0, 0 ); 5756 case float_round_up: 5757 return 5758 aSign ? packFloatx80( 1, 0, 0 ) 5759 : packFloatx80( 0, 0x3FFF, LIT64( 0x8000000000000000 ) ); 5760 } 5761 return packFloatx80( aSign, 0, 0 ); 5762 } 5763 lastBitMask = 1; 5764 lastBitMask <<= 0x403E - aExp; 5765 roundBitsMask = lastBitMask - 1; 5766 z = a; 5767 switch (status->float_rounding_mode) { 5768 case float_round_nearest_even: 5769 z.low += lastBitMask>>1; 5770 if ((z.low & roundBitsMask) == 0) { 5771 z.low &= ~lastBitMask; 5772 } 5773 break; 5774 case float_round_ties_away: 5775 z.low += lastBitMask >> 1; 5776 break; 5777 case float_round_to_zero: 5778 break; 5779 case float_round_up: 5780 if (!extractFloatx80Sign(z)) { 5781 z.low += roundBitsMask; 5782 } 5783 break; 5784 case float_round_down: 5785 if (extractFloatx80Sign(z)) { 5786 z.low += roundBitsMask; 5787 } 5788 break; 5789 default: 5790 abort(); 5791 } 5792 z.low &= ~ roundBitsMask; 5793 if ( z.low == 0 ) { 5794 ++z.high; 5795 z.low = LIT64( 0x8000000000000000 ); 5796 } 5797 if (z.low != a.low) { 5798 status->float_exception_flags |= float_flag_inexact; 5799 } 5800 return z; 5801 5802 } 5803 5804 /*---------------------------------------------------------------------------- 5805 | Returns the result of adding the absolute values of the extended double- 5806 | precision floating-point values `a' and `b'. If `zSign' is 1, the sum is 5807 | negated before being returned. `zSign' is ignored if the result is a NaN. 5808 | The addition is performed according to the IEC/IEEE Standard for Binary 5809 | Floating-Point Arithmetic. 5810 *----------------------------------------------------------------------------*/ 5811 5812 static floatx80 addFloatx80Sigs(floatx80 a, floatx80 b, flag zSign, 5813 float_status *status) 5814 { 5815 int32_t aExp, bExp, zExp; 5816 uint64_t aSig, bSig, zSig0, zSig1; 5817 int32_t expDiff; 5818 5819 aSig = extractFloatx80Frac( a ); 5820 aExp = extractFloatx80Exp( a ); 5821 bSig = extractFloatx80Frac( b ); 5822 bExp = extractFloatx80Exp( b ); 5823 expDiff = aExp - bExp; 5824 if ( 0 < expDiff ) { 5825 if ( aExp == 0x7FFF ) { 5826 if ((uint64_t)(aSig << 1)) { 5827 return propagateFloatx80NaN(a, b, status); 5828 } 5829 return a; 5830 } 5831 if ( bExp == 0 ) --expDiff; 5832 shift64ExtraRightJamming( bSig, 0, expDiff, &bSig, &zSig1 ); 5833 zExp = aExp; 5834 } 5835 else if ( expDiff < 0 ) { 5836 if ( bExp == 0x7FFF ) { 5837 if ((uint64_t)(bSig << 1)) { 5838 return propagateFloatx80NaN(a, b, status); 5839 } 5840 return packFloatx80(zSign, 5841 floatx80_infinity_high, 5842 floatx80_infinity_low); 5843 } 5844 if ( aExp == 0 ) ++expDiff; 5845 shift64ExtraRightJamming( aSig, 0, - expDiff, &aSig, &zSig1 ); 5846 zExp = bExp; 5847 } 5848 else { 5849 if ( aExp == 0x7FFF ) { 5850 if ( (uint64_t) ( ( aSig | bSig )<<1 ) ) { 5851 return propagateFloatx80NaN(a, b, status); 5852 } 5853 return a; 5854 } 5855 zSig1 = 0; 5856 zSig0 = aSig + bSig; 5857 if ( aExp == 0 ) { 5858 normalizeFloatx80Subnormal( zSig0, &zExp, &zSig0 ); 5859 goto roundAndPack; 5860 } 5861 zExp = aExp; 5862 goto shiftRight1; 5863 } 5864 zSig0 = aSig + bSig; 5865 if ( (int64_t) zSig0 < 0 ) goto roundAndPack; 5866 shiftRight1: 5867 shift64ExtraRightJamming( zSig0, zSig1, 1, &zSig0, &zSig1 ); 5868 zSig0 |= LIT64( 0x8000000000000000 ); 5869 ++zExp; 5870 roundAndPack: 5871 return roundAndPackFloatx80(status->floatx80_rounding_precision, 5872 zSign, zExp, zSig0, zSig1, status); 5873 } 5874 5875 /*---------------------------------------------------------------------------- 5876 | Returns the result of subtracting the absolute values of the extended 5877 | double-precision floating-point values `a' and `b'. If `zSign' is 1, the 5878 | difference is negated before being returned. `zSign' is ignored if the 5879 | result is a NaN. The subtraction is performed according to the IEC/IEEE 5880 | Standard for Binary Floating-Point Arithmetic. 5881 *----------------------------------------------------------------------------*/ 5882 5883 static floatx80 subFloatx80Sigs(floatx80 a, floatx80 b, flag zSign, 5884 float_status *status) 5885 { 5886 int32_t aExp, bExp, zExp; 5887 uint64_t aSig, bSig, zSig0, zSig1; 5888 int32_t expDiff; 5889 5890 aSig = extractFloatx80Frac( a ); 5891 aExp = extractFloatx80Exp( a ); 5892 bSig = extractFloatx80Frac( b ); 5893 bExp = extractFloatx80Exp( b ); 5894 expDiff = aExp - bExp; 5895 if ( 0 < expDiff ) goto aExpBigger; 5896 if ( expDiff < 0 ) goto bExpBigger; 5897 if ( aExp == 0x7FFF ) { 5898 if ( (uint64_t) ( ( aSig | bSig )<<1 ) ) { 5899 return propagateFloatx80NaN(a, b, status); 5900 } 5901 float_raise(float_flag_invalid, status); 5902 return floatx80_default_nan(status); 5903 } 5904 if ( aExp == 0 ) { 5905 aExp = 1; 5906 bExp = 1; 5907 } 5908 zSig1 = 0; 5909 if ( bSig < aSig ) goto aBigger; 5910 if ( aSig < bSig ) goto bBigger; 5911 return packFloatx80(status->float_rounding_mode == float_round_down, 0, 0); 5912 bExpBigger: 5913 if ( bExp == 0x7FFF ) { 5914 if ((uint64_t)(bSig << 1)) { 5915 return propagateFloatx80NaN(a, b, status); 5916 } 5917 return packFloatx80(zSign ^ 1, floatx80_infinity_high, 5918 floatx80_infinity_low); 5919 } 5920 if ( aExp == 0 ) ++expDiff; 5921 shift128RightJamming( aSig, 0, - expDiff, &aSig, &zSig1 ); 5922 bBigger: 5923 sub128( bSig, 0, aSig, zSig1, &zSig0, &zSig1 ); 5924 zExp = bExp; 5925 zSign ^= 1; 5926 goto normalizeRoundAndPack; 5927 aExpBigger: 5928 if ( aExp == 0x7FFF ) { 5929 if ((uint64_t)(aSig << 1)) { 5930 return propagateFloatx80NaN(a, b, status); 5931 } 5932 return a; 5933 } 5934 if ( bExp == 0 ) --expDiff; 5935 shift128RightJamming( bSig, 0, expDiff, &bSig, &zSig1 ); 5936 aBigger: 5937 sub128( aSig, 0, bSig, zSig1, &zSig0, &zSig1 ); 5938 zExp = aExp; 5939 normalizeRoundAndPack: 5940 return normalizeRoundAndPackFloatx80(status->floatx80_rounding_precision, 5941 zSign, zExp, zSig0, zSig1, status); 5942 } 5943 5944 /*---------------------------------------------------------------------------- 5945 | Returns the result of adding the extended double-precision floating-point 5946 | values `a' and `b'. The operation is performed according to the IEC/IEEE 5947 | Standard for Binary Floating-Point Arithmetic. 5948 *----------------------------------------------------------------------------*/ 5949 5950 floatx80 floatx80_add(floatx80 a, floatx80 b, float_status *status) 5951 { 5952 flag aSign, bSign; 5953 5954 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 5955 float_raise(float_flag_invalid, status); 5956 return floatx80_default_nan(status); 5957 } 5958 aSign = extractFloatx80Sign( a ); 5959 bSign = extractFloatx80Sign( b ); 5960 if ( aSign == bSign ) { 5961 return addFloatx80Sigs(a, b, aSign, status); 5962 } 5963 else { 5964 return subFloatx80Sigs(a, b, aSign, status); 5965 } 5966 5967 } 5968 5969 /*---------------------------------------------------------------------------- 5970 | Returns the result of subtracting the extended double-precision floating- 5971 | point values `a' and `b'. The operation is performed according to the 5972 | IEC/IEEE Standard for Binary Floating-Point Arithmetic. 5973 *----------------------------------------------------------------------------*/ 5974 5975 floatx80 floatx80_sub(floatx80 a, floatx80 b, float_status *status) 5976 { 5977 flag aSign, bSign; 5978 5979 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 5980 float_raise(float_flag_invalid, status); 5981 return floatx80_default_nan(status); 5982 } 5983 aSign = extractFloatx80Sign( a ); 5984 bSign = extractFloatx80Sign( b ); 5985 if ( aSign == bSign ) { 5986 return subFloatx80Sigs(a, b, aSign, status); 5987 } 5988 else { 5989 return addFloatx80Sigs(a, b, aSign, status); 5990 } 5991 5992 } 5993 5994 /*---------------------------------------------------------------------------- 5995 | Returns the result of multiplying the extended double-precision floating- 5996 | point values `a' and `b'. The operation is performed according to the 5997 | IEC/IEEE Standard for Binary Floating-Point Arithmetic. 5998 *----------------------------------------------------------------------------*/ 5999 6000 floatx80 floatx80_mul(floatx80 a, floatx80 b, float_status *status) 6001 { 6002 flag aSign, bSign, zSign; 6003 int32_t aExp, bExp, zExp; 6004 uint64_t aSig, bSig, zSig0, zSig1; 6005 6006 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 6007 float_raise(float_flag_invalid, status); 6008 return floatx80_default_nan(status); 6009 } 6010 aSig = extractFloatx80Frac( a ); 6011 aExp = extractFloatx80Exp( a ); 6012 aSign = extractFloatx80Sign( a ); 6013 bSig = extractFloatx80Frac( b ); 6014 bExp = extractFloatx80Exp( b ); 6015 bSign = extractFloatx80Sign( b ); 6016 zSign = aSign ^ bSign; 6017 if ( aExp == 0x7FFF ) { 6018 if ( (uint64_t) ( aSig<<1 ) 6019 || ( ( bExp == 0x7FFF ) && (uint64_t) ( bSig<<1 ) ) ) { 6020 return propagateFloatx80NaN(a, b, status); 6021 } 6022 if ( ( bExp | bSig ) == 0 ) goto invalid; 6023 return packFloatx80(zSign, floatx80_infinity_high, 6024 floatx80_infinity_low); 6025 } 6026 if ( bExp == 0x7FFF ) { 6027 if ((uint64_t)(bSig << 1)) { 6028 return propagateFloatx80NaN(a, b, status); 6029 } 6030 if ( ( aExp | aSig ) == 0 ) { 6031 invalid: 6032 float_raise(float_flag_invalid, status); 6033 return floatx80_default_nan(status); 6034 } 6035 return packFloatx80(zSign, floatx80_infinity_high, 6036 floatx80_infinity_low); 6037 } 6038 if ( aExp == 0 ) { 6039 if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 ); 6040 normalizeFloatx80Subnormal( aSig, &aExp, &aSig ); 6041 } 6042 if ( bExp == 0 ) { 6043 if ( bSig == 0 ) return packFloatx80( zSign, 0, 0 ); 6044 normalizeFloatx80Subnormal( bSig, &bExp, &bSig ); 6045 } 6046 zExp = aExp + bExp - 0x3FFE; 6047 mul64To128( aSig, bSig, &zSig0, &zSig1 ); 6048 if ( 0 < (int64_t) zSig0 ) { 6049 shortShift128Left( zSig0, zSig1, 1, &zSig0, &zSig1 ); 6050 --zExp; 6051 } 6052 return roundAndPackFloatx80(status->floatx80_rounding_precision, 6053 zSign, zExp, zSig0, zSig1, status); 6054 } 6055 6056 /*---------------------------------------------------------------------------- 6057 | Returns the result of dividing the extended double-precision floating-point 6058 | value `a' by the corresponding value `b'. The operation is performed 6059 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 6060 *----------------------------------------------------------------------------*/ 6061 6062 floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status) 6063 { 6064 flag aSign, bSign, zSign; 6065 int32_t aExp, bExp, zExp; 6066 uint64_t aSig, bSig, zSig0, zSig1; 6067 uint64_t rem0, rem1, rem2, term0, term1, term2; 6068 6069 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 6070 float_raise(float_flag_invalid, status); 6071 return floatx80_default_nan(status); 6072 } 6073 aSig = extractFloatx80Frac( a ); 6074 aExp = extractFloatx80Exp( a ); 6075 aSign = extractFloatx80Sign( a ); 6076 bSig = extractFloatx80Frac( b ); 6077 bExp = extractFloatx80Exp( b ); 6078 bSign = extractFloatx80Sign( b ); 6079 zSign = aSign ^ bSign; 6080 if ( aExp == 0x7FFF ) { 6081 if ((uint64_t)(aSig << 1)) { 6082 return propagateFloatx80NaN(a, b, status); 6083 } 6084 if ( bExp == 0x7FFF ) { 6085 if ((uint64_t)(bSig << 1)) { 6086 return propagateFloatx80NaN(a, b, status); 6087 } 6088 goto invalid; 6089 } 6090 return packFloatx80(zSign, floatx80_infinity_high, 6091 floatx80_infinity_low); 6092 } 6093 if ( bExp == 0x7FFF ) { 6094 if ((uint64_t)(bSig << 1)) { 6095 return propagateFloatx80NaN(a, b, status); 6096 } 6097 return packFloatx80( zSign, 0, 0 ); 6098 } 6099 if ( bExp == 0 ) { 6100 if ( bSig == 0 ) { 6101 if ( ( aExp | aSig ) == 0 ) { 6102 invalid: 6103 float_raise(float_flag_invalid, status); 6104 return floatx80_default_nan(status); 6105 } 6106 float_raise(float_flag_divbyzero, status); 6107 return packFloatx80(zSign, floatx80_infinity_high, 6108 floatx80_infinity_low); 6109 } 6110 normalizeFloatx80Subnormal( bSig, &bExp, &bSig ); 6111 } 6112 if ( aExp == 0 ) { 6113 if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 ); 6114 normalizeFloatx80Subnormal( aSig, &aExp, &aSig ); 6115 } 6116 zExp = aExp - bExp + 0x3FFE; 6117 rem1 = 0; 6118 if ( bSig <= aSig ) { 6119 shift128Right( aSig, 0, 1, &aSig, &rem1 ); 6120 ++zExp; 6121 } 6122 zSig0 = estimateDiv128To64( aSig, rem1, bSig ); 6123 mul64To128( bSig, zSig0, &term0, &term1 ); 6124 sub128( aSig, rem1, term0, term1, &rem0, &rem1 ); 6125 while ( (int64_t) rem0 < 0 ) { 6126 --zSig0; 6127 add128( rem0, rem1, 0, bSig, &rem0, &rem1 ); 6128 } 6129 zSig1 = estimateDiv128To64( rem1, 0, bSig ); 6130 if ( (uint64_t) ( zSig1<<1 ) <= 8 ) { 6131 mul64To128( bSig, zSig1, &term1, &term2 ); 6132 sub128( rem1, 0, term1, term2, &rem1, &rem2 ); 6133 while ( (int64_t) rem1 < 0 ) { 6134 --zSig1; 6135 add128( rem1, rem2, 0, bSig, &rem1, &rem2 ); 6136 } 6137 zSig1 |= ( ( rem1 | rem2 ) != 0 ); 6138 } 6139 return roundAndPackFloatx80(status->floatx80_rounding_precision, 6140 zSign, zExp, zSig0, zSig1, status); 6141 } 6142 6143 /*---------------------------------------------------------------------------- 6144 | Returns the remainder of the extended double-precision floating-point value 6145 | `a' with respect to the corresponding value `b'. The operation is performed 6146 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 6147 *----------------------------------------------------------------------------*/ 6148 6149 floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status) 6150 { 6151 flag aSign, zSign; 6152 int32_t aExp, bExp, expDiff; 6153 uint64_t aSig0, aSig1, bSig; 6154 uint64_t q, term0, term1, alternateASig0, alternateASig1; 6155 6156 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 6157 float_raise(float_flag_invalid, status); 6158 return floatx80_default_nan(status); 6159 } 6160 aSig0 = extractFloatx80Frac( a ); 6161 aExp = extractFloatx80Exp( a ); 6162 aSign = extractFloatx80Sign( a ); 6163 bSig = extractFloatx80Frac( b ); 6164 bExp = extractFloatx80Exp( b ); 6165 if ( aExp == 0x7FFF ) { 6166 if ( (uint64_t) ( aSig0<<1 ) 6167 || ( ( bExp == 0x7FFF ) && (uint64_t) ( bSig<<1 ) ) ) { 6168 return propagateFloatx80NaN(a, b, status); 6169 } 6170 goto invalid; 6171 } 6172 if ( bExp == 0x7FFF ) { 6173 if ((uint64_t)(bSig << 1)) { 6174 return propagateFloatx80NaN(a, b, status); 6175 } 6176 return a; 6177 } 6178 if ( bExp == 0 ) { 6179 if ( bSig == 0 ) { 6180 invalid: 6181 float_raise(float_flag_invalid, status); 6182 return floatx80_default_nan(status); 6183 } 6184 normalizeFloatx80Subnormal( bSig, &bExp, &bSig ); 6185 } 6186 if ( aExp == 0 ) { 6187 if ( (uint64_t) ( aSig0<<1 ) == 0 ) return a; 6188 normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 ); 6189 } 6190 bSig |= LIT64( 0x8000000000000000 ); 6191 zSign = aSign; 6192 expDiff = aExp - bExp; 6193 aSig1 = 0; 6194 if ( expDiff < 0 ) { 6195 if ( expDiff < -1 ) return a; 6196 shift128Right( aSig0, 0, 1, &aSig0, &aSig1 ); 6197 expDiff = 0; 6198 } 6199 q = ( bSig <= aSig0 ); 6200 if ( q ) aSig0 -= bSig; 6201 expDiff -= 64; 6202 while ( 0 < expDiff ) { 6203 q = estimateDiv128To64( aSig0, aSig1, bSig ); 6204 q = ( 2 < q ) ? q - 2 : 0; 6205 mul64To128( bSig, q, &term0, &term1 ); 6206 sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 ); 6207 shortShift128Left( aSig0, aSig1, 62, &aSig0, &aSig1 ); 6208 expDiff -= 62; 6209 } 6210 expDiff += 64; 6211 if ( 0 < expDiff ) { 6212 q = estimateDiv128To64( aSig0, aSig1, bSig ); 6213 q = ( 2 < q ) ? q - 2 : 0; 6214 q >>= 64 - expDiff; 6215 mul64To128( bSig, q<<( 64 - expDiff ), &term0, &term1 ); 6216 sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 ); 6217 shortShift128Left( 0, bSig, 64 - expDiff, &term0, &term1 ); 6218 while ( le128( term0, term1, aSig0, aSig1 ) ) { 6219 ++q; 6220 sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 ); 6221 } 6222 } 6223 else { 6224 term1 = 0; 6225 term0 = bSig; 6226 } 6227 sub128( term0, term1, aSig0, aSig1, &alternateASig0, &alternateASig1 ); 6228 if ( lt128( alternateASig0, alternateASig1, aSig0, aSig1 ) 6229 || ( eq128( alternateASig0, alternateASig1, aSig0, aSig1 ) 6230 && ( q & 1 ) ) 6231 ) { 6232 aSig0 = alternateASig0; 6233 aSig1 = alternateASig1; 6234 zSign = ! zSign; 6235 } 6236 return 6237 normalizeRoundAndPackFloatx80( 6238 80, zSign, bExp + expDiff, aSig0, aSig1, status); 6239 6240 } 6241 6242 /*---------------------------------------------------------------------------- 6243 | Returns the square root of the extended double-precision floating-point 6244 | value `a'. The operation is performed according to the IEC/IEEE Standard 6245 | for Binary Floating-Point Arithmetic. 6246 *----------------------------------------------------------------------------*/ 6247 6248 floatx80 floatx80_sqrt(floatx80 a, float_status *status) 6249 { 6250 flag aSign; 6251 int32_t aExp, zExp; 6252 uint64_t aSig0, aSig1, zSig0, zSig1, doubleZSig0; 6253 uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3; 6254 6255 if (floatx80_invalid_encoding(a)) { 6256 float_raise(float_flag_invalid, status); 6257 return floatx80_default_nan(status); 6258 } 6259 aSig0 = extractFloatx80Frac( a ); 6260 aExp = extractFloatx80Exp( a ); 6261 aSign = extractFloatx80Sign( a ); 6262 if ( aExp == 0x7FFF ) { 6263 if ((uint64_t)(aSig0 << 1)) { 6264 return propagateFloatx80NaN(a, a, status); 6265 } 6266 if ( ! aSign ) return a; 6267 goto invalid; 6268 } 6269 if ( aSign ) { 6270 if ( ( aExp | aSig0 ) == 0 ) return a; 6271 invalid: 6272 float_raise(float_flag_invalid, status); 6273 return floatx80_default_nan(status); 6274 } 6275 if ( aExp == 0 ) { 6276 if ( aSig0 == 0 ) return packFloatx80( 0, 0, 0 ); 6277 normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 ); 6278 } 6279 zExp = ( ( aExp - 0x3FFF )>>1 ) + 0x3FFF; 6280 zSig0 = estimateSqrt32( aExp, aSig0>>32 ); 6281 shift128Right( aSig0, 0, 2 + ( aExp & 1 ), &aSig0, &aSig1 ); 6282 zSig0 = estimateDiv128To64( aSig0, aSig1, zSig0<<32 ) + ( zSig0<<30 ); 6283 doubleZSig0 = zSig0<<1; 6284 mul64To128( zSig0, zSig0, &term0, &term1 ); 6285 sub128( aSig0, aSig1, term0, term1, &rem0, &rem1 ); 6286 while ( (int64_t) rem0 < 0 ) { 6287 --zSig0; 6288 doubleZSig0 -= 2; 6289 add128( rem0, rem1, zSig0>>63, doubleZSig0 | 1, &rem0, &rem1 ); 6290 } 6291 zSig1 = estimateDiv128To64( rem1, 0, doubleZSig0 ); 6292 if ( ( zSig1 & LIT64( 0x3FFFFFFFFFFFFFFF ) ) <= 5 ) { 6293 if ( zSig1 == 0 ) zSig1 = 1; 6294 mul64To128( doubleZSig0, zSig1, &term1, &term2 ); 6295 sub128( rem1, 0, term1, term2, &rem1, &rem2 ); 6296 mul64To128( zSig1, zSig1, &term2, &term3 ); 6297 sub192( rem1, rem2, 0, 0, term2, term3, &rem1, &rem2, &rem3 ); 6298 while ( (int64_t) rem1 < 0 ) { 6299 --zSig1; 6300 shortShift128Left( 0, zSig1, 1, &term2, &term3 ); 6301 term3 |= 1; 6302 term2 |= doubleZSig0; 6303 add192( rem1, rem2, rem3, 0, term2, term3, &rem1, &rem2, &rem3 ); 6304 } 6305 zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 ); 6306 } 6307 shortShift128Left( 0, zSig1, 1, &zSig0, &zSig1 ); 6308 zSig0 |= doubleZSig0; 6309 return roundAndPackFloatx80(status->floatx80_rounding_precision, 6310 0, zExp, zSig0, zSig1, status); 6311 } 6312 6313 /*---------------------------------------------------------------------------- 6314 | Returns 1 if the extended double-precision floating-point value `a' is equal 6315 | to the corresponding value `b', and 0 otherwise. The invalid exception is 6316 | raised if either operand is a NaN. Otherwise, the comparison is performed 6317 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 6318 *----------------------------------------------------------------------------*/ 6319 6320 int floatx80_eq(floatx80 a, floatx80 b, float_status *status) 6321 { 6322 6323 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b) 6324 || (extractFloatx80Exp(a) == 0x7FFF 6325 && (uint64_t) (extractFloatx80Frac(a) << 1)) 6326 || (extractFloatx80Exp(b) == 0x7FFF 6327 && (uint64_t) (extractFloatx80Frac(b) << 1)) 6328 ) { 6329 float_raise(float_flag_invalid, status); 6330 return 0; 6331 } 6332 return 6333 ( a.low == b.low ) 6334 && ( ( a.high == b.high ) 6335 || ( ( a.low == 0 ) 6336 && ( (uint16_t) ( ( a.high | b.high )<<1 ) == 0 ) ) 6337 ); 6338 6339 } 6340 6341 /*---------------------------------------------------------------------------- 6342 | Returns 1 if the extended double-precision floating-point value `a' is 6343 | less than or equal to the corresponding value `b', and 0 otherwise. The 6344 | invalid exception is raised if either operand is a NaN. The comparison is 6345 | performed according to the IEC/IEEE Standard for Binary Floating-Point 6346 | Arithmetic. 6347 *----------------------------------------------------------------------------*/ 6348 6349 int floatx80_le(floatx80 a, floatx80 b, float_status *status) 6350 { 6351 flag aSign, bSign; 6352 6353 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b) 6354 || (extractFloatx80Exp(a) == 0x7FFF 6355 && (uint64_t) (extractFloatx80Frac(a) << 1)) 6356 || (extractFloatx80Exp(b) == 0x7FFF 6357 && (uint64_t) (extractFloatx80Frac(b) << 1)) 6358 ) { 6359 float_raise(float_flag_invalid, status); 6360 return 0; 6361 } 6362 aSign = extractFloatx80Sign( a ); 6363 bSign = extractFloatx80Sign( b ); 6364 if ( aSign != bSign ) { 6365 return 6366 aSign 6367 || ( ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 6368 == 0 ); 6369 } 6370 return 6371 aSign ? le128( b.high, b.low, a.high, a.low ) 6372 : le128( a.high, a.low, b.high, b.low ); 6373 6374 } 6375 6376 /*---------------------------------------------------------------------------- 6377 | Returns 1 if the extended double-precision floating-point value `a' is 6378 | less than the corresponding value `b', and 0 otherwise. The invalid 6379 | exception is raised if either operand is a NaN. The comparison is performed 6380 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 6381 *----------------------------------------------------------------------------*/ 6382 6383 int floatx80_lt(floatx80 a, floatx80 b, float_status *status) 6384 { 6385 flag aSign, bSign; 6386 6387 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b) 6388 || (extractFloatx80Exp(a) == 0x7FFF 6389 && (uint64_t) (extractFloatx80Frac(a) << 1)) 6390 || (extractFloatx80Exp(b) == 0x7FFF 6391 && (uint64_t) (extractFloatx80Frac(b) << 1)) 6392 ) { 6393 float_raise(float_flag_invalid, status); 6394 return 0; 6395 } 6396 aSign = extractFloatx80Sign( a ); 6397 bSign = extractFloatx80Sign( b ); 6398 if ( aSign != bSign ) { 6399 return 6400 aSign 6401 && ( ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 6402 != 0 ); 6403 } 6404 return 6405 aSign ? lt128( b.high, b.low, a.high, a.low ) 6406 : lt128( a.high, a.low, b.high, b.low ); 6407 6408 } 6409 6410 /*---------------------------------------------------------------------------- 6411 | Returns 1 if the extended double-precision floating-point values `a' and `b' 6412 | cannot be compared, and 0 otherwise. The invalid exception is raised if 6413 | either operand is a NaN. The comparison is performed according to the 6414 | IEC/IEEE Standard for Binary Floating-Point Arithmetic. 6415 *----------------------------------------------------------------------------*/ 6416 int floatx80_unordered(floatx80 a, floatx80 b, float_status *status) 6417 { 6418 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b) 6419 || (extractFloatx80Exp(a) == 0x7FFF 6420 && (uint64_t) (extractFloatx80Frac(a) << 1)) 6421 || (extractFloatx80Exp(b) == 0x7FFF 6422 && (uint64_t) (extractFloatx80Frac(b) << 1)) 6423 ) { 6424 float_raise(float_flag_invalid, status); 6425 return 1; 6426 } 6427 return 0; 6428 } 6429 6430 /*---------------------------------------------------------------------------- 6431 | Returns 1 if the extended double-precision floating-point value `a' is 6432 | equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not 6433 | cause an exception. The comparison is performed according to the IEC/IEEE 6434 | Standard for Binary Floating-Point Arithmetic. 6435 *----------------------------------------------------------------------------*/ 6436 6437 int floatx80_eq_quiet(floatx80 a, floatx80 b, float_status *status) 6438 { 6439 6440 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 6441 float_raise(float_flag_invalid, status); 6442 return 0; 6443 } 6444 if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) 6445 && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) 6446 || ( ( extractFloatx80Exp( b ) == 0x7FFF ) 6447 && (uint64_t) ( extractFloatx80Frac( b )<<1 ) ) 6448 ) { 6449 if (floatx80_is_signaling_nan(a, status) 6450 || floatx80_is_signaling_nan(b, status)) { 6451 float_raise(float_flag_invalid, status); 6452 } 6453 return 0; 6454 } 6455 return 6456 ( a.low == b.low ) 6457 && ( ( a.high == b.high ) 6458 || ( ( a.low == 0 ) 6459 && ( (uint16_t) ( ( a.high | b.high )<<1 ) == 0 ) ) 6460 ); 6461 6462 } 6463 6464 /*---------------------------------------------------------------------------- 6465 | Returns 1 if the extended double-precision floating-point value `a' is less 6466 | than or equal to the corresponding value `b', and 0 otherwise. Quiet NaNs 6467 | do not cause an exception. Otherwise, the comparison is performed according 6468 | to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 6469 *----------------------------------------------------------------------------*/ 6470 6471 int floatx80_le_quiet(floatx80 a, floatx80 b, float_status *status) 6472 { 6473 flag aSign, bSign; 6474 6475 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 6476 float_raise(float_flag_invalid, status); 6477 return 0; 6478 } 6479 if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) 6480 && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) 6481 || ( ( extractFloatx80Exp( b ) == 0x7FFF ) 6482 && (uint64_t) ( extractFloatx80Frac( b )<<1 ) ) 6483 ) { 6484 if (floatx80_is_signaling_nan(a, status) 6485 || floatx80_is_signaling_nan(b, status)) { 6486 float_raise(float_flag_invalid, status); 6487 } 6488 return 0; 6489 } 6490 aSign = extractFloatx80Sign( a ); 6491 bSign = extractFloatx80Sign( b ); 6492 if ( aSign != bSign ) { 6493 return 6494 aSign 6495 || ( ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 6496 == 0 ); 6497 } 6498 return 6499 aSign ? le128( b.high, b.low, a.high, a.low ) 6500 : le128( a.high, a.low, b.high, b.low ); 6501 6502 } 6503 6504 /*---------------------------------------------------------------------------- 6505 | Returns 1 if the extended double-precision floating-point value `a' is less 6506 | than the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause 6507 | an exception. Otherwise, the comparison is performed according to the 6508 | IEC/IEEE Standard for Binary Floating-Point Arithmetic. 6509 *----------------------------------------------------------------------------*/ 6510 6511 int floatx80_lt_quiet(floatx80 a, floatx80 b, float_status *status) 6512 { 6513 flag aSign, bSign; 6514 6515 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 6516 float_raise(float_flag_invalid, status); 6517 return 0; 6518 } 6519 if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) 6520 && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) 6521 || ( ( extractFloatx80Exp( b ) == 0x7FFF ) 6522 && (uint64_t) ( extractFloatx80Frac( b )<<1 ) ) 6523 ) { 6524 if (floatx80_is_signaling_nan(a, status) 6525 || floatx80_is_signaling_nan(b, status)) { 6526 float_raise(float_flag_invalid, status); 6527 } 6528 return 0; 6529 } 6530 aSign = extractFloatx80Sign( a ); 6531 bSign = extractFloatx80Sign( b ); 6532 if ( aSign != bSign ) { 6533 return 6534 aSign 6535 && ( ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 6536 != 0 ); 6537 } 6538 return 6539 aSign ? lt128( b.high, b.low, a.high, a.low ) 6540 : lt128( a.high, a.low, b.high, b.low ); 6541 6542 } 6543 6544 /*---------------------------------------------------------------------------- 6545 | Returns 1 if the extended double-precision floating-point values `a' and `b' 6546 | cannot be compared, and 0 otherwise. Quiet NaNs do not cause an exception. 6547 | The comparison is performed according to the IEC/IEEE Standard for Binary 6548 | Floating-Point Arithmetic. 6549 *----------------------------------------------------------------------------*/ 6550 int floatx80_unordered_quiet(floatx80 a, floatx80 b, float_status *status) 6551 { 6552 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 6553 float_raise(float_flag_invalid, status); 6554 return 1; 6555 } 6556 if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) 6557 && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) 6558 || ( ( extractFloatx80Exp( b ) == 0x7FFF ) 6559 && (uint64_t) ( extractFloatx80Frac( b )<<1 ) ) 6560 ) { 6561 if (floatx80_is_signaling_nan(a, status) 6562 || floatx80_is_signaling_nan(b, status)) { 6563 float_raise(float_flag_invalid, status); 6564 } 6565 return 1; 6566 } 6567 return 0; 6568 } 6569 6570 /*---------------------------------------------------------------------------- 6571 | Returns the result of converting the quadruple-precision floating-point 6572 | value `a' to the 32-bit two's complement integer format. The conversion 6573 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 6574 | Arithmetic---which means in particular that the conversion is rounded 6575 | according to the current rounding mode. If `a' is a NaN, the largest 6576 | positive integer is returned. Otherwise, if the conversion overflows, the 6577 | largest integer with the same sign as `a' is returned. 6578 *----------------------------------------------------------------------------*/ 6579 6580 int32_t float128_to_int32(float128 a, float_status *status) 6581 { 6582 flag aSign; 6583 int32_t aExp, shiftCount; 6584 uint64_t aSig0, aSig1; 6585 6586 aSig1 = extractFloat128Frac1( a ); 6587 aSig0 = extractFloat128Frac0( a ); 6588 aExp = extractFloat128Exp( a ); 6589 aSign = extractFloat128Sign( a ); 6590 if ( ( aExp == 0x7FFF ) && ( aSig0 | aSig1 ) ) aSign = 0; 6591 if ( aExp ) aSig0 |= LIT64( 0x0001000000000000 ); 6592 aSig0 |= ( aSig1 != 0 ); 6593 shiftCount = 0x4028 - aExp; 6594 if ( 0 < shiftCount ) shift64RightJamming( aSig0, shiftCount, &aSig0 ); 6595 return roundAndPackInt32(aSign, aSig0, status); 6596 6597 } 6598 6599 /*---------------------------------------------------------------------------- 6600 | Returns the result of converting the quadruple-precision floating-point 6601 | value `a' to the 32-bit two's complement integer format. The conversion 6602 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 6603 | Arithmetic, except that the conversion is always rounded toward zero. If 6604 | `a' is a NaN, the largest positive integer is returned. Otherwise, if the 6605 | conversion overflows, the largest integer with the same sign as `a' is 6606 | returned. 6607 *----------------------------------------------------------------------------*/ 6608 6609 int32_t float128_to_int32_round_to_zero(float128 a, float_status *status) 6610 { 6611 flag aSign; 6612 int32_t aExp, shiftCount; 6613 uint64_t aSig0, aSig1, savedASig; 6614 int32_t z; 6615 6616 aSig1 = extractFloat128Frac1( a ); 6617 aSig0 = extractFloat128Frac0( a ); 6618 aExp = extractFloat128Exp( a ); 6619 aSign = extractFloat128Sign( a ); 6620 aSig0 |= ( aSig1 != 0 ); 6621 if ( 0x401E < aExp ) { 6622 if ( ( aExp == 0x7FFF ) && aSig0 ) aSign = 0; 6623 goto invalid; 6624 } 6625 else if ( aExp < 0x3FFF ) { 6626 if (aExp || aSig0) { 6627 status->float_exception_flags |= float_flag_inexact; 6628 } 6629 return 0; 6630 } 6631 aSig0 |= LIT64( 0x0001000000000000 ); 6632 shiftCount = 0x402F - aExp; 6633 savedASig = aSig0; 6634 aSig0 >>= shiftCount; 6635 z = aSig0; 6636 if ( aSign ) z = - z; 6637 if ( ( z < 0 ) ^ aSign ) { 6638 invalid: 6639 float_raise(float_flag_invalid, status); 6640 return aSign ? (int32_t) 0x80000000 : 0x7FFFFFFF; 6641 } 6642 if ( ( aSig0<<shiftCount ) != savedASig ) { 6643 status->float_exception_flags |= float_flag_inexact; 6644 } 6645 return z; 6646 6647 } 6648 6649 /*---------------------------------------------------------------------------- 6650 | Returns the result of converting the quadruple-precision floating-point 6651 | value `a' to the 64-bit two's complement integer format. The conversion 6652 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 6653 | Arithmetic---which means in particular that the conversion is rounded 6654 | according to the current rounding mode. If `a' is a NaN, the largest 6655 | positive integer is returned. Otherwise, if the conversion overflows, the 6656 | largest integer with the same sign as `a' is returned. 6657 *----------------------------------------------------------------------------*/ 6658 6659 int64_t float128_to_int64(float128 a, float_status *status) 6660 { 6661 flag aSign; 6662 int32_t aExp, shiftCount; 6663 uint64_t aSig0, aSig1; 6664 6665 aSig1 = extractFloat128Frac1( a ); 6666 aSig0 = extractFloat128Frac0( a ); 6667 aExp = extractFloat128Exp( a ); 6668 aSign = extractFloat128Sign( a ); 6669 if ( aExp ) aSig0 |= LIT64( 0x0001000000000000 ); 6670 shiftCount = 0x402F - aExp; 6671 if ( shiftCount <= 0 ) { 6672 if ( 0x403E < aExp ) { 6673 float_raise(float_flag_invalid, status); 6674 if ( ! aSign 6675 || ( ( aExp == 0x7FFF ) 6676 && ( aSig1 || ( aSig0 != LIT64( 0x0001000000000000 ) ) ) 6677 ) 6678 ) { 6679 return LIT64( 0x7FFFFFFFFFFFFFFF ); 6680 } 6681 return (int64_t) LIT64( 0x8000000000000000 ); 6682 } 6683 shortShift128Left( aSig0, aSig1, - shiftCount, &aSig0, &aSig1 ); 6684 } 6685 else { 6686 shift64ExtraRightJamming( aSig0, aSig1, shiftCount, &aSig0, &aSig1 ); 6687 } 6688 return roundAndPackInt64(aSign, aSig0, aSig1, status); 6689 6690 } 6691 6692 /*---------------------------------------------------------------------------- 6693 | Returns the result of converting the quadruple-precision floating-point 6694 | value `a' to the 64-bit two's complement integer format. The conversion 6695 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 6696 | Arithmetic, except that the conversion is always rounded toward zero. 6697 | If `a' is a NaN, the largest positive integer is returned. Otherwise, if 6698 | the conversion overflows, the largest integer with the same sign as `a' is 6699 | returned. 6700 *----------------------------------------------------------------------------*/ 6701 6702 int64_t float128_to_int64_round_to_zero(float128 a, float_status *status) 6703 { 6704 flag aSign; 6705 int32_t aExp, shiftCount; 6706 uint64_t aSig0, aSig1; 6707 int64_t z; 6708 6709 aSig1 = extractFloat128Frac1( a ); 6710 aSig0 = extractFloat128Frac0( a ); 6711 aExp = extractFloat128Exp( a ); 6712 aSign = extractFloat128Sign( a ); 6713 if ( aExp ) aSig0 |= LIT64( 0x0001000000000000 ); 6714 shiftCount = aExp - 0x402F; 6715 if ( 0 < shiftCount ) { 6716 if ( 0x403E <= aExp ) { 6717 aSig0 &= LIT64( 0x0000FFFFFFFFFFFF ); 6718 if ( ( a.high == LIT64( 0xC03E000000000000 ) ) 6719 && ( aSig1 < LIT64( 0x0002000000000000 ) ) ) { 6720 if (aSig1) { 6721 status->float_exception_flags |= float_flag_inexact; 6722 } 6723 } 6724 else { 6725 float_raise(float_flag_invalid, status); 6726 if ( ! aSign || ( ( aExp == 0x7FFF ) && ( aSig0 | aSig1 ) ) ) { 6727 return LIT64( 0x7FFFFFFFFFFFFFFF ); 6728 } 6729 } 6730 return (int64_t) LIT64( 0x8000000000000000 ); 6731 } 6732 z = ( aSig0<<shiftCount ) | ( aSig1>>( ( - shiftCount ) & 63 ) ); 6733 if ( (uint64_t) ( aSig1<<shiftCount ) ) { 6734 status->float_exception_flags |= float_flag_inexact; 6735 } 6736 } 6737 else { 6738 if ( aExp < 0x3FFF ) { 6739 if ( aExp | aSig0 | aSig1 ) { 6740 status->float_exception_flags |= float_flag_inexact; 6741 } 6742 return 0; 6743 } 6744 z = aSig0>>( - shiftCount ); 6745 if ( aSig1 6746 || ( shiftCount && (uint64_t) ( aSig0<<( shiftCount & 63 ) ) ) ) { 6747 status->float_exception_flags |= float_flag_inexact; 6748 } 6749 } 6750 if ( aSign ) z = - z; 6751 return z; 6752 6753 } 6754 6755 /*---------------------------------------------------------------------------- 6756 | Returns the result of converting the quadruple-precision floating-point value 6757 | `a' to the 64-bit unsigned integer format. The conversion is 6758 | performed according to the IEC/IEEE Standard for Binary Floating-Point 6759 | Arithmetic---which means in particular that the conversion is rounded 6760 | according to the current rounding mode. If `a' is a NaN, the largest 6761 | positive integer is returned. If the conversion overflows, the 6762 | largest unsigned integer is returned. If 'a' is negative, the value is 6763 | rounded and zero is returned; negative values that do not round to zero 6764 | will raise the inexact exception. 6765 *----------------------------------------------------------------------------*/ 6766 6767 uint64_t float128_to_uint64(float128 a, float_status *status) 6768 { 6769 flag aSign; 6770 int aExp; 6771 int shiftCount; 6772 uint64_t aSig0, aSig1; 6773 6774 aSig0 = extractFloat128Frac0(a); 6775 aSig1 = extractFloat128Frac1(a); 6776 aExp = extractFloat128Exp(a); 6777 aSign = extractFloat128Sign(a); 6778 if (aSign && (aExp > 0x3FFE)) { 6779 float_raise(float_flag_invalid, status); 6780 if (float128_is_any_nan(a)) { 6781 return LIT64(0xFFFFFFFFFFFFFFFF); 6782 } else { 6783 return 0; 6784 } 6785 } 6786 if (aExp) { 6787 aSig0 |= LIT64(0x0001000000000000); 6788 } 6789 shiftCount = 0x402F - aExp; 6790 if (shiftCount <= 0) { 6791 if (0x403E < aExp) { 6792 float_raise(float_flag_invalid, status); 6793 return LIT64(0xFFFFFFFFFFFFFFFF); 6794 } 6795 shortShift128Left(aSig0, aSig1, -shiftCount, &aSig0, &aSig1); 6796 } else { 6797 shift64ExtraRightJamming(aSig0, aSig1, shiftCount, &aSig0, &aSig1); 6798 } 6799 return roundAndPackUint64(aSign, aSig0, aSig1, status); 6800 } 6801 6802 uint64_t float128_to_uint64_round_to_zero(float128 a, float_status *status) 6803 { 6804 uint64_t v; 6805 signed char current_rounding_mode = status->float_rounding_mode; 6806 6807 set_float_rounding_mode(float_round_to_zero, status); 6808 v = float128_to_uint64(a, status); 6809 set_float_rounding_mode(current_rounding_mode, status); 6810 6811 return v; 6812 } 6813 6814 /*---------------------------------------------------------------------------- 6815 | Returns the result of converting the quadruple-precision floating-point 6816 | value `a' to the 32-bit unsigned integer format. The conversion 6817 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 6818 | Arithmetic except that the conversion is always rounded toward zero. 6819 | If `a' is a NaN, the largest positive integer is returned. Otherwise, 6820 | if the conversion overflows, the largest unsigned integer is returned. 6821 | If 'a' is negative, the value is rounded and zero is returned; negative 6822 | values that do not round to zero will raise the inexact exception. 6823 *----------------------------------------------------------------------------*/ 6824 6825 uint32_t float128_to_uint32_round_to_zero(float128 a, float_status *status) 6826 { 6827 uint64_t v; 6828 uint32_t res; 6829 int old_exc_flags = get_float_exception_flags(status); 6830 6831 v = float128_to_uint64_round_to_zero(a, status); 6832 if (v > 0xffffffff) { 6833 res = 0xffffffff; 6834 } else { 6835 return v; 6836 } 6837 set_float_exception_flags(old_exc_flags, status); 6838 float_raise(float_flag_invalid, status); 6839 return res; 6840 } 6841 6842 /*---------------------------------------------------------------------------- 6843 | Returns the result of converting the quadruple-precision floating-point value 6844 | `a' to the 32-bit unsigned integer format. The conversion is 6845 | performed according to the IEC/IEEE Standard for Binary Floating-Point 6846 | Arithmetic---which means in particular that the conversion is rounded 6847 | according to the current rounding mode. If `a' is a NaN, the largest 6848 | positive integer is returned. If the conversion overflows, the 6849 | largest unsigned integer is returned. If 'a' is negative, the value is 6850 | rounded and zero is returned; negative values that do not round to zero 6851 | will raise the inexact exception. 6852 *----------------------------------------------------------------------------*/ 6853 6854 uint32_t float128_to_uint32(float128 a, float_status *status) 6855 { 6856 uint64_t v; 6857 uint32_t res; 6858 int old_exc_flags = get_float_exception_flags(status); 6859 6860 v = float128_to_uint64(a, status); 6861 if (v > 0xffffffff) { 6862 res = 0xffffffff; 6863 } else { 6864 return v; 6865 } 6866 set_float_exception_flags(old_exc_flags, status); 6867 float_raise(float_flag_invalid, status); 6868 return res; 6869 } 6870 6871 /*---------------------------------------------------------------------------- 6872 | Returns the result of converting the quadruple-precision floating-point 6873 | value `a' to the single-precision floating-point format. The conversion 6874 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 6875 | Arithmetic. 6876 *----------------------------------------------------------------------------*/ 6877 6878 float32 float128_to_float32(float128 a, float_status *status) 6879 { 6880 flag aSign; 6881 int32_t aExp; 6882 uint64_t aSig0, aSig1; 6883 uint32_t zSig; 6884 6885 aSig1 = extractFloat128Frac1( a ); 6886 aSig0 = extractFloat128Frac0( a ); 6887 aExp = extractFloat128Exp( a ); 6888 aSign = extractFloat128Sign( a ); 6889 if ( aExp == 0x7FFF ) { 6890 if ( aSig0 | aSig1 ) { 6891 return commonNaNToFloat32(float128ToCommonNaN(a, status), status); 6892 } 6893 return packFloat32( aSign, 0xFF, 0 ); 6894 } 6895 aSig0 |= ( aSig1 != 0 ); 6896 shift64RightJamming( aSig0, 18, &aSig0 ); 6897 zSig = aSig0; 6898 if ( aExp || zSig ) { 6899 zSig |= 0x40000000; 6900 aExp -= 0x3F81; 6901 } 6902 return roundAndPackFloat32(aSign, aExp, zSig, status); 6903 6904 } 6905 6906 /*---------------------------------------------------------------------------- 6907 | Returns the result of converting the quadruple-precision floating-point 6908 | value `a' to the double-precision floating-point format. The conversion 6909 | is performed according to the IEC/IEEE Standard for Binary Floating-Point 6910 | Arithmetic. 6911 *----------------------------------------------------------------------------*/ 6912 6913 float64 float128_to_float64(float128 a, float_status *status) 6914 { 6915 flag aSign; 6916 int32_t aExp; 6917 uint64_t aSig0, aSig1; 6918 6919 aSig1 = extractFloat128Frac1( a ); 6920 aSig0 = extractFloat128Frac0( a ); 6921 aExp = extractFloat128Exp( a ); 6922 aSign = extractFloat128Sign( a ); 6923 if ( aExp == 0x7FFF ) { 6924 if ( aSig0 | aSig1 ) { 6925 return commonNaNToFloat64(float128ToCommonNaN(a, status), status); 6926 } 6927 return packFloat64( aSign, 0x7FF, 0 ); 6928 } 6929 shortShift128Left( aSig0, aSig1, 14, &aSig0, &aSig1 ); 6930 aSig0 |= ( aSig1 != 0 ); 6931 if ( aExp || aSig0 ) { 6932 aSig0 |= LIT64( 0x4000000000000000 ); 6933 aExp -= 0x3C01; 6934 } 6935 return roundAndPackFloat64(aSign, aExp, aSig0, status); 6936 6937 } 6938 6939 /*---------------------------------------------------------------------------- 6940 | Returns the result of converting the quadruple-precision floating-point 6941 | value `a' to the extended double-precision floating-point format. The 6942 | conversion is performed according to the IEC/IEEE Standard for Binary 6943 | Floating-Point Arithmetic. 6944 *----------------------------------------------------------------------------*/ 6945 6946 floatx80 float128_to_floatx80(float128 a, float_status *status) 6947 { 6948 flag aSign; 6949 int32_t aExp; 6950 uint64_t aSig0, aSig1; 6951 6952 aSig1 = extractFloat128Frac1( a ); 6953 aSig0 = extractFloat128Frac0( a ); 6954 aExp = extractFloat128Exp( a ); 6955 aSign = extractFloat128Sign( a ); 6956 if ( aExp == 0x7FFF ) { 6957 if ( aSig0 | aSig1 ) { 6958 return commonNaNToFloatx80(float128ToCommonNaN(a, status), status); 6959 } 6960 return packFloatx80(aSign, floatx80_infinity_high, 6961 floatx80_infinity_low); 6962 } 6963 if ( aExp == 0 ) { 6964 if ( ( aSig0 | aSig1 ) == 0 ) return packFloatx80( aSign, 0, 0 ); 6965 normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 ); 6966 } 6967 else { 6968 aSig0 |= LIT64( 0x0001000000000000 ); 6969 } 6970 shortShift128Left( aSig0, aSig1, 15, &aSig0, &aSig1 ); 6971 return roundAndPackFloatx80(80, aSign, aExp, aSig0, aSig1, status); 6972 6973 } 6974 6975 /*---------------------------------------------------------------------------- 6976 | Rounds the quadruple-precision floating-point value `a' to an integer, and 6977 | returns the result as a quadruple-precision floating-point value. The 6978 | operation is performed according to the IEC/IEEE Standard for Binary 6979 | Floating-Point Arithmetic. 6980 *----------------------------------------------------------------------------*/ 6981 6982 float128 float128_round_to_int(float128 a, float_status *status) 6983 { 6984 flag aSign; 6985 int32_t aExp; 6986 uint64_t lastBitMask, roundBitsMask; 6987 float128 z; 6988 6989 aExp = extractFloat128Exp( a ); 6990 if ( 0x402F <= aExp ) { 6991 if ( 0x406F <= aExp ) { 6992 if ( ( aExp == 0x7FFF ) 6993 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) 6994 ) { 6995 return propagateFloat128NaN(a, a, status); 6996 } 6997 return a; 6998 } 6999 lastBitMask = 1; 7000 lastBitMask = ( lastBitMask<<( 0x406E - aExp ) )<<1; 7001 roundBitsMask = lastBitMask - 1; 7002 z = a; 7003 switch (status->float_rounding_mode) { 7004 case float_round_nearest_even: 7005 if ( lastBitMask ) { 7006 add128( z.high, z.low, 0, lastBitMask>>1, &z.high, &z.low ); 7007 if ( ( z.low & roundBitsMask ) == 0 ) z.low &= ~ lastBitMask; 7008 } 7009 else { 7010 if ( (int64_t) z.low < 0 ) { 7011 ++z.high; 7012 if ( (uint64_t) ( z.low<<1 ) == 0 ) z.high &= ~1; 7013 } 7014 } 7015 break; 7016 case float_round_ties_away: 7017 if (lastBitMask) { 7018 add128(z.high, z.low, 0, lastBitMask >> 1, &z.high, &z.low); 7019 } else { 7020 if ((int64_t) z.low < 0) { 7021 ++z.high; 7022 } 7023 } 7024 break; 7025 case float_round_to_zero: 7026 break; 7027 case float_round_up: 7028 if (!extractFloat128Sign(z)) { 7029 add128(z.high, z.low, 0, roundBitsMask, &z.high, &z.low); 7030 } 7031 break; 7032 case float_round_down: 7033 if (extractFloat128Sign(z)) { 7034 add128(z.high, z.low, 0, roundBitsMask, &z.high, &z.low); 7035 } 7036 break; 7037 case float_round_to_odd: 7038 /* 7039 * Note that if lastBitMask == 0, the last bit is the lsb 7040 * of high, and roundBitsMask == -1. 7041 */ 7042 if ((lastBitMask ? z.low & lastBitMask : z.high & 1) == 0) { 7043 add128(z.high, z.low, 0, roundBitsMask, &z.high, &z.low); 7044 } 7045 break; 7046 default: 7047 abort(); 7048 } 7049 z.low &= ~ roundBitsMask; 7050 } 7051 else { 7052 if ( aExp < 0x3FFF ) { 7053 if ( ( ( (uint64_t) ( a.high<<1 ) ) | a.low ) == 0 ) return a; 7054 status->float_exception_flags |= float_flag_inexact; 7055 aSign = extractFloat128Sign( a ); 7056 switch (status->float_rounding_mode) { 7057 case float_round_nearest_even: 7058 if ( ( aExp == 0x3FFE ) 7059 && ( extractFloat128Frac0( a ) 7060 | extractFloat128Frac1( a ) ) 7061 ) { 7062 return packFloat128( aSign, 0x3FFF, 0, 0 ); 7063 } 7064 break; 7065 case float_round_ties_away: 7066 if (aExp == 0x3FFE) { 7067 return packFloat128(aSign, 0x3FFF, 0, 0); 7068 } 7069 break; 7070 case float_round_down: 7071 return 7072 aSign ? packFloat128( 1, 0x3FFF, 0, 0 ) 7073 : packFloat128( 0, 0, 0, 0 ); 7074 case float_round_up: 7075 return 7076 aSign ? packFloat128( 1, 0, 0, 0 ) 7077 : packFloat128( 0, 0x3FFF, 0, 0 ); 7078 7079 case float_round_to_odd: 7080 return packFloat128(aSign, 0x3FFF, 0, 0); 7081 } 7082 return packFloat128( aSign, 0, 0, 0 ); 7083 } 7084 lastBitMask = 1; 7085 lastBitMask <<= 0x402F - aExp; 7086 roundBitsMask = lastBitMask - 1; 7087 z.low = 0; 7088 z.high = a.high; 7089 switch (status->float_rounding_mode) { 7090 case float_round_nearest_even: 7091 z.high += lastBitMask>>1; 7092 if ( ( ( z.high & roundBitsMask ) | a.low ) == 0 ) { 7093 z.high &= ~ lastBitMask; 7094 } 7095 break; 7096 case float_round_ties_away: 7097 z.high += lastBitMask>>1; 7098 break; 7099 case float_round_to_zero: 7100 break; 7101 case float_round_up: 7102 if (!extractFloat128Sign(z)) { 7103 z.high |= ( a.low != 0 ); 7104 z.high += roundBitsMask; 7105 } 7106 break; 7107 case float_round_down: 7108 if (extractFloat128Sign(z)) { 7109 z.high |= (a.low != 0); 7110 z.high += roundBitsMask; 7111 } 7112 break; 7113 case float_round_to_odd: 7114 if ((z.high & lastBitMask) == 0) { 7115 z.high |= (a.low != 0); 7116 z.high += roundBitsMask; 7117 } 7118 break; 7119 default: 7120 abort(); 7121 } 7122 z.high &= ~ roundBitsMask; 7123 } 7124 if ( ( z.low != a.low ) || ( z.high != a.high ) ) { 7125 status->float_exception_flags |= float_flag_inexact; 7126 } 7127 return z; 7128 7129 } 7130 7131 /*---------------------------------------------------------------------------- 7132 | Returns the result of adding the absolute values of the quadruple-precision 7133 | floating-point values `a' and `b'. If `zSign' is 1, the sum is negated 7134 | before being returned. `zSign' is ignored if the result is a NaN. 7135 | The addition is performed according to the IEC/IEEE Standard for Binary 7136 | Floating-Point Arithmetic. 7137 *----------------------------------------------------------------------------*/ 7138 7139 static float128 addFloat128Sigs(float128 a, float128 b, flag zSign, 7140 float_status *status) 7141 { 7142 int32_t aExp, bExp, zExp; 7143 uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2; 7144 int32_t expDiff; 7145 7146 aSig1 = extractFloat128Frac1( a ); 7147 aSig0 = extractFloat128Frac0( a ); 7148 aExp = extractFloat128Exp( a ); 7149 bSig1 = extractFloat128Frac1( b ); 7150 bSig0 = extractFloat128Frac0( b ); 7151 bExp = extractFloat128Exp( b ); 7152 expDiff = aExp - bExp; 7153 if ( 0 < expDiff ) { 7154 if ( aExp == 0x7FFF ) { 7155 if (aSig0 | aSig1) { 7156 return propagateFloat128NaN(a, b, status); 7157 } 7158 return a; 7159 } 7160 if ( bExp == 0 ) { 7161 --expDiff; 7162 } 7163 else { 7164 bSig0 |= LIT64( 0x0001000000000000 ); 7165 } 7166 shift128ExtraRightJamming( 7167 bSig0, bSig1, 0, expDiff, &bSig0, &bSig1, &zSig2 ); 7168 zExp = aExp; 7169 } 7170 else if ( expDiff < 0 ) { 7171 if ( bExp == 0x7FFF ) { 7172 if (bSig0 | bSig1) { 7173 return propagateFloat128NaN(a, b, status); 7174 } 7175 return packFloat128( zSign, 0x7FFF, 0, 0 ); 7176 } 7177 if ( aExp == 0 ) { 7178 ++expDiff; 7179 } 7180 else { 7181 aSig0 |= LIT64( 0x0001000000000000 ); 7182 } 7183 shift128ExtraRightJamming( 7184 aSig0, aSig1, 0, - expDiff, &aSig0, &aSig1, &zSig2 ); 7185 zExp = bExp; 7186 } 7187 else { 7188 if ( aExp == 0x7FFF ) { 7189 if ( aSig0 | aSig1 | bSig0 | bSig1 ) { 7190 return propagateFloat128NaN(a, b, status); 7191 } 7192 return a; 7193 } 7194 add128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 ); 7195 if ( aExp == 0 ) { 7196 if (status->flush_to_zero) { 7197 if (zSig0 | zSig1) { 7198 float_raise(float_flag_output_denormal, status); 7199 } 7200 return packFloat128(zSign, 0, 0, 0); 7201 } 7202 return packFloat128( zSign, 0, zSig0, zSig1 ); 7203 } 7204 zSig2 = 0; 7205 zSig0 |= LIT64( 0x0002000000000000 ); 7206 zExp = aExp; 7207 goto shiftRight1; 7208 } 7209 aSig0 |= LIT64( 0x0001000000000000 ); 7210 add128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 ); 7211 --zExp; 7212 if ( zSig0 < LIT64( 0x0002000000000000 ) ) goto roundAndPack; 7213 ++zExp; 7214 shiftRight1: 7215 shift128ExtraRightJamming( 7216 zSig0, zSig1, zSig2, 1, &zSig0, &zSig1, &zSig2 ); 7217 roundAndPack: 7218 return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status); 7219 7220 } 7221 7222 /*---------------------------------------------------------------------------- 7223 | Returns the result of subtracting the absolute values of the quadruple- 7224 | precision floating-point values `a' and `b'. If `zSign' is 1, the 7225 | difference is negated before being returned. `zSign' is ignored if the 7226 | result is a NaN. The subtraction is performed according to the IEC/IEEE 7227 | Standard for Binary Floating-Point Arithmetic. 7228 *----------------------------------------------------------------------------*/ 7229 7230 static float128 subFloat128Sigs(float128 a, float128 b, flag zSign, 7231 float_status *status) 7232 { 7233 int32_t aExp, bExp, zExp; 7234 uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1; 7235 int32_t expDiff; 7236 7237 aSig1 = extractFloat128Frac1( a ); 7238 aSig0 = extractFloat128Frac0( a ); 7239 aExp = extractFloat128Exp( a ); 7240 bSig1 = extractFloat128Frac1( b ); 7241 bSig0 = extractFloat128Frac0( b ); 7242 bExp = extractFloat128Exp( b ); 7243 expDiff = aExp - bExp; 7244 shortShift128Left( aSig0, aSig1, 14, &aSig0, &aSig1 ); 7245 shortShift128Left( bSig0, bSig1, 14, &bSig0, &bSig1 ); 7246 if ( 0 < expDiff ) goto aExpBigger; 7247 if ( expDiff < 0 ) goto bExpBigger; 7248 if ( aExp == 0x7FFF ) { 7249 if ( aSig0 | aSig1 | bSig0 | bSig1 ) { 7250 return propagateFloat128NaN(a, b, status); 7251 } 7252 float_raise(float_flag_invalid, status); 7253 return float128_default_nan(status); 7254 } 7255 if ( aExp == 0 ) { 7256 aExp = 1; 7257 bExp = 1; 7258 } 7259 if ( bSig0 < aSig0 ) goto aBigger; 7260 if ( aSig0 < bSig0 ) goto bBigger; 7261 if ( bSig1 < aSig1 ) goto aBigger; 7262 if ( aSig1 < bSig1 ) goto bBigger; 7263 return packFloat128(status->float_rounding_mode == float_round_down, 7264 0, 0, 0); 7265 bExpBigger: 7266 if ( bExp == 0x7FFF ) { 7267 if (bSig0 | bSig1) { 7268 return propagateFloat128NaN(a, b, status); 7269 } 7270 return packFloat128( zSign ^ 1, 0x7FFF, 0, 0 ); 7271 } 7272 if ( aExp == 0 ) { 7273 ++expDiff; 7274 } 7275 else { 7276 aSig0 |= LIT64( 0x4000000000000000 ); 7277 } 7278 shift128RightJamming( aSig0, aSig1, - expDiff, &aSig0, &aSig1 ); 7279 bSig0 |= LIT64( 0x4000000000000000 ); 7280 bBigger: 7281 sub128( bSig0, bSig1, aSig0, aSig1, &zSig0, &zSig1 ); 7282 zExp = bExp; 7283 zSign ^= 1; 7284 goto normalizeRoundAndPack; 7285 aExpBigger: 7286 if ( aExp == 0x7FFF ) { 7287 if (aSig0 | aSig1) { 7288 return propagateFloat128NaN(a, b, status); 7289 } 7290 return a; 7291 } 7292 if ( bExp == 0 ) { 7293 --expDiff; 7294 } 7295 else { 7296 bSig0 |= LIT64( 0x4000000000000000 ); 7297 } 7298 shift128RightJamming( bSig0, bSig1, expDiff, &bSig0, &bSig1 ); 7299 aSig0 |= LIT64( 0x4000000000000000 ); 7300 aBigger: 7301 sub128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 ); 7302 zExp = aExp; 7303 normalizeRoundAndPack: 7304 --zExp; 7305 return normalizeRoundAndPackFloat128(zSign, zExp - 14, zSig0, zSig1, 7306 status); 7307 7308 } 7309 7310 /*---------------------------------------------------------------------------- 7311 | Returns the result of adding the quadruple-precision floating-point values 7312 | `a' and `b'. The operation is performed according to the IEC/IEEE Standard 7313 | for Binary Floating-Point Arithmetic. 7314 *----------------------------------------------------------------------------*/ 7315 7316 float128 float128_add(float128 a, float128 b, float_status *status) 7317 { 7318 flag aSign, bSign; 7319 7320 aSign = extractFloat128Sign( a ); 7321 bSign = extractFloat128Sign( b ); 7322 if ( aSign == bSign ) { 7323 return addFloat128Sigs(a, b, aSign, status); 7324 } 7325 else { 7326 return subFloat128Sigs(a, b, aSign, status); 7327 } 7328 7329 } 7330 7331 /*---------------------------------------------------------------------------- 7332 | Returns the result of subtracting the quadruple-precision floating-point 7333 | values `a' and `b'. The operation is performed according to the IEC/IEEE 7334 | Standard for Binary Floating-Point Arithmetic. 7335 *----------------------------------------------------------------------------*/ 7336 7337 float128 float128_sub(float128 a, float128 b, float_status *status) 7338 { 7339 flag aSign, bSign; 7340 7341 aSign = extractFloat128Sign( a ); 7342 bSign = extractFloat128Sign( b ); 7343 if ( aSign == bSign ) { 7344 return subFloat128Sigs(a, b, aSign, status); 7345 } 7346 else { 7347 return addFloat128Sigs(a, b, aSign, status); 7348 } 7349 7350 } 7351 7352 /*---------------------------------------------------------------------------- 7353 | Returns the result of multiplying the quadruple-precision floating-point 7354 | values `a' and `b'. The operation is performed according to the IEC/IEEE 7355 | Standard for Binary Floating-Point Arithmetic. 7356 *----------------------------------------------------------------------------*/ 7357 7358 float128 float128_mul(float128 a, float128 b, float_status *status) 7359 { 7360 flag aSign, bSign, zSign; 7361 int32_t aExp, bExp, zExp; 7362 uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2, zSig3; 7363 7364 aSig1 = extractFloat128Frac1( a ); 7365 aSig0 = extractFloat128Frac0( a ); 7366 aExp = extractFloat128Exp( a ); 7367 aSign = extractFloat128Sign( a ); 7368 bSig1 = extractFloat128Frac1( b ); 7369 bSig0 = extractFloat128Frac0( b ); 7370 bExp = extractFloat128Exp( b ); 7371 bSign = extractFloat128Sign( b ); 7372 zSign = aSign ^ bSign; 7373 if ( aExp == 0x7FFF ) { 7374 if ( ( aSig0 | aSig1 ) 7375 || ( ( bExp == 0x7FFF ) && ( bSig0 | bSig1 ) ) ) { 7376 return propagateFloat128NaN(a, b, status); 7377 } 7378 if ( ( bExp | bSig0 | bSig1 ) == 0 ) goto invalid; 7379 return packFloat128( zSign, 0x7FFF, 0, 0 ); 7380 } 7381 if ( bExp == 0x7FFF ) { 7382 if (bSig0 | bSig1) { 7383 return propagateFloat128NaN(a, b, status); 7384 } 7385 if ( ( aExp | aSig0 | aSig1 ) == 0 ) { 7386 invalid: 7387 float_raise(float_flag_invalid, status); 7388 return float128_default_nan(status); 7389 } 7390 return packFloat128( zSign, 0x7FFF, 0, 0 ); 7391 } 7392 if ( aExp == 0 ) { 7393 if ( ( aSig0 | aSig1 ) == 0 ) return packFloat128( zSign, 0, 0, 0 ); 7394 normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 ); 7395 } 7396 if ( bExp == 0 ) { 7397 if ( ( bSig0 | bSig1 ) == 0 ) return packFloat128( zSign, 0, 0, 0 ); 7398 normalizeFloat128Subnormal( bSig0, bSig1, &bExp, &bSig0, &bSig1 ); 7399 } 7400 zExp = aExp + bExp - 0x4000; 7401 aSig0 |= LIT64( 0x0001000000000000 ); 7402 shortShift128Left( bSig0, bSig1, 16, &bSig0, &bSig1 ); 7403 mul128To256( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1, &zSig2, &zSig3 ); 7404 add128( zSig0, zSig1, aSig0, aSig1, &zSig0, &zSig1 ); 7405 zSig2 |= ( zSig3 != 0 ); 7406 if ( LIT64( 0x0002000000000000 ) <= zSig0 ) { 7407 shift128ExtraRightJamming( 7408 zSig0, zSig1, zSig2, 1, &zSig0, &zSig1, &zSig2 ); 7409 ++zExp; 7410 } 7411 return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status); 7412 7413 } 7414 7415 /*---------------------------------------------------------------------------- 7416 | Returns the result of dividing the quadruple-precision floating-point value 7417 | `a' by the corresponding value `b'. The operation is performed according to 7418 | the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 7419 *----------------------------------------------------------------------------*/ 7420 7421 float128 float128_div(float128 a, float128 b, float_status *status) 7422 { 7423 flag aSign, bSign, zSign; 7424 int32_t aExp, bExp, zExp; 7425 uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2; 7426 uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3; 7427 7428 aSig1 = extractFloat128Frac1( a ); 7429 aSig0 = extractFloat128Frac0( a ); 7430 aExp = extractFloat128Exp( a ); 7431 aSign = extractFloat128Sign( a ); 7432 bSig1 = extractFloat128Frac1( b ); 7433 bSig0 = extractFloat128Frac0( b ); 7434 bExp = extractFloat128Exp( b ); 7435 bSign = extractFloat128Sign( b ); 7436 zSign = aSign ^ bSign; 7437 if ( aExp == 0x7FFF ) { 7438 if (aSig0 | aSig1) { 7439 return propagateFloat128NaN(a, b, status); 7440 } 7441 if ( bExp == 0x7FFF ) { 7442 if (bSig0 | bSig1) { 7443 return propagateFloat128NaN(a, b, status); 7444 } 7445 goto invalid; 7446 } 7447 return packFloat128( zSign, 0x7FFF, 0, 0 ); 7448 } 7449 if ( bExp == 0x7FFF ) { 7450 if (bSig0 | bSig1) { 7451 return propagateFloat128NaN(a, b, status); 7452 } 7453 return packFloat128( zSign, 0, 0, 0 ); 7454 } 7455 if ( bExp == 0 ) { 7456 if ( ( bSig0 | bSig1 ) == 0 ) { 7457 if ( ( aExp | aSig0 | aSig1 ) == 0 ) { 7458 invalid: 7459 float_raise(float_flag_invalid, status); 7460 return float128_default_nan(status); 7461 } 7462 float_raise(float_flag_divbyzero, status); 7463 return packFloat128( zSign, 0x7FFF, 0, 0 ); 7464 } 7465 normalizeFloat128Subnormal( bSig0, bSig1, &bExp, &bSig0, &bSig1 ); 7466 } 7467 if ( aExp == 0 ) { 7468 if ( ( aSig0 | aSig1 ) == 0 ) return packFloat128( zSign, 0, 0, 0 ); 7469 normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 ); 7470 } 7471 zExp = aExp - bExp + 0x3FFD; 7472 shortShift128Left( 7473 aSig0 | LIT64( 0x0001000000000000 ), aSig1, 15, &aSig0, &aSig1 ); 7474 shortShift128Left( 7475 bSig0 | LIT64( 0x0001000000000000 ), bSig1, 15, &bSig0, &bSig1 ); 7476 if ( le128( bSig0, bSig1, aSig0, aSig1 ) ) { 7477 shift128Right( aSig0, aSig1, 1, &aSig0, &aSig1 ); 7478 ++zExp; 7479 } 7480 zSig0 = estimateDiv128To64( aSig0, aSig1, bSig0 ); 7481 mul128By64To192( bSig0, bSig1, zSig0, &term0, &term1, &term2 ); 7482 sub192( aSig0, aSig1, 0, term0, term1, term2, &rem0, &rem1, &rem2 ); 7483 while ( (int64_t) rem0 < 0 ) { 7484 --zSig0; 7485 add192( rem0, rem1, rem2, 0, bSig0, bSig1, &rem0, &rem1, &rem2 ); 7486 } 7487 zSig1 = estimateDiv128To64( rem1, rem2, bSig0 ); 7488 if ( ( zSig1 & 0x3FFF ) <= 4 ) { 7489 mul128By64To192( bSig0, bSig1, zSig1, &term1, &term2, &term3 ); 7490 sub192( rem1, rem2, 0, term1, term2, term3, &rem1, &rem2, &rem3 ); 7491 while ( (int64_t) rem1 < 0 ) { 7492 --zSig1; 7493 add192( rem1, rem2, rem3, 0, bSig0, bSig1, &rem1, &rem2, &rem3 ); 7494 } 7495 zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 ); 7496 } 7497 shift128ExtraRightJamming( zSig0, zSig1, 0, 15, &zSig0, &zSig1, &zSig2 ); 7498 return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status); 7499 7500 } 7501 7502 /*---------------------------------------------------------------------------- 7503 | Returns the remainder of the quadruple-precision floating-point value `a' 7504 | with respect to the corresponding value `b'. The operation is performed 7505 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 7506 *----------------------------------------------------------------------------*/ 7507 7508 float128 float128_rem(float128 a, float128 b, float_status *status) 7509 { 7510 flag aSign, zSign; 7511 int32_t aExp, bExp, expDiff; 7512 uint64_t aSig0, aSig1, bSig0, bSig1, q, term0, term1, term2; 7513 uint64_t allZero, alternateASig0, alternateASig1, sigMean1; 7514 int64_t sigMean0; 7515 7516 aSig1 = extractFloat128Frac1( a ); 7517 aSig0 = extractFloat128Frac0( a ); 7518 aExp = extractFloat128Exp( a ); 7519 aSign = extractFloat128Sign( a ); 7520 bSig1 = extractFloat128Frac1( b ); 7521 bSig0 = extractFloat128Frac0( b ); 7522 bExp = extractFloat128Exp( b ); 7523 if ( aExp == 0x7FFF ) { 7524 if ( ( aSig0 | aSig1 ) 7525 || ( ( bExp == 0x7FFF ) && ( bSig0 | bSig1 ) ) ) { 7526 return propagateFloat128NaN(a, b, status); 7527 } 7528 goto invalid; 7529 } 7530 if ( bExp == 0x7FFF ) { 7531 if (bSig0 | bSig1) { 7532 return propagateFloat128NaN(a, b, status); 7533 } 7534 return a; 7535 } 7536 if ( bExp == 0 ) { 7537 if ( ( bSig0 | bSig1 ) == 0 ) { 7538 invalid: 7539 float_raise(float_flag_invalid, status); 7540 return float128_default_nan(status); 7541 } 7542 normalizeFloat128Subnormal( bSig0, bSig1, &bExp, &bSig0, &bSig1 ); 7543 } 7544 if ( aExp == 0 ) { 7545 if ( ( aSig0 | aSig1 ) == 0 ) return a; 7546 normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 ); 7547 } 7548 expDiff = aExp - bExp; 7549 if ( expDiff < -1 ) return a; 7550 shortShift128Left( 7551 aSig0 | LIT64( 0x0001000000000000 ), 7552 aSig1, 7553 15 - ( expDiff < 0 ), 7554 &aSig0, 7555 &aSig1 7556 ); 7557 shortShift128Left( 7558 bSig0 | LIT64( 0x0001000000000000 ), bSig1, 15, &bSig0, &bSig1 ); 7559 q = le128( bSig0, bSig1, aSig0, aSig1 ); 7560 if ( q ) sub128( aSig0, aSig1, bSig0, bSig1, &aSig0, &aSig1 ); 7561 expDiff -= 64; 7562 while ( 0 < expDiff ) { 7563 q = estimateDiv128To64( aSig0, aSig1, bSig0 ); 7564 q = ( 4 < q ) ? q - 4 : 0; 7565 mul128By64To192( bSig0, bSig1, q, &term0, &term1, &term2 ); 7566 shortShift192Left( term0, term1, term2, 61, &term1, &term2, &allZero ); 7567 shortShift128Left( aSig0, aSig1, 61, &aSig0, &allZero ); 7568 sub128( aSig0, 0, term1, term2, &aSig0, &aSig1 ); 7569 expDiff -= 61; 7570 } 7571 if ( -64 < expDiff ) { 7572 q = estimateDiv128To64( aSig0, aSig1, bSig0 ); 7573 q = ( 4 < q ) ? q - 4 : 0; 7574 q >>= - expDiff; 7575 shift128Right( bSig0, bSig1, 12, &bSig0, &bSig1 ); 7576 expDiff += 52; 7577 if ( expDiff < 0 ) { 7578 shift128Right( aSig0, aSig1, - expDiff, &aSig0, &aSig1 ); 7579 } 7580 else { 7581 shortShift128Left( aSig0, aSig1, expDiff, &aSig0, &aSig1 ); 7582 } 7583 mul128By64To192( bSig0, bSig1, q, &term0, &term1, &term2 ); 7584 sub128( aSig0, aSig1, term1, term2, &aSig0, &aSig1 ); 7585 } 7586 else { 7587 shift128Right( aSig0, aSig1, 12, &aSig0, &aSig1 ); 7588 shift128Right( bSig0, bSig1, 12, &bSig0, &bSig1 ); 7589 } 7590 do { 7591 alternateASig0 = aSig0; 7592 alternateASig1 = aSig1; 7593 ++q; 7594 sub128( aSig0, aSig1, bSig0, bSig1, &aSig0, &aSig1 ); 7595 } while ( 0 <= (int64_t) aSig0 ); 7596 add128( 7597 aSig0, aSig1, alternateASig0, alternateASig1, (uint64_t *)&sigMean0, &sigMean1 ); 7598 if ( ( sigMean0 < 0 ) 7599 || ( ( ( sigMean0 | sigMean1 ) == 0 ) && ( q & 1 ) ) ) { 7600 aSig0 = alternateASig0; 7601 aSig1 = alternateASig1; 7602 } 7603 zSign = ( (int64_t) aSig0 < 0 ); 7604 if ( zSign ) sub128( 0, 0, aSig0, aSig1, &aSig0, &aSig1 ); 7605 return normalizeRoundAndPackFloat128(aSign ^ zSign, bExp - 4, aSig0, aSig1, 7606 status); 7607 } 7608 7609 /*---------------------------------------------------------------------------- 7610 | Returns the square root of the quadruple-precision floating-point value `a'. 7611 | The operation is performed according to the IEC/IEEE Standard for Binary 7612 | Floating-Point Arithmetic. 7613 *----------------------------------------------------------------------------*/ 7614 7615 float128 float128_sqrt(float128 a, float_status *status) 7616 { 7617 flag aSign; 7618 int32_t aExp, zExp; 7619 uint64_t aSig0, aSig1, zSig0, zSig1, zSig2, doubleZSig0; 7620 uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3; 7621 7622 aSig1 = extractFloat128Frac1( a ); 7623 aSig0 = extractFloat128Frac0( a ); 7624 aExp = extractFloat128Exp( a ); 7625 aSign = extractFloat128Sign( a ); 7626 if ( aExp == 0x7FFF ) { 7627 if (aSig0 | aSig1) { 7628 return propagateFloat128NaN(a, a, status); 7629 } 7630 if ( ! aSign ) return a; 7631 goto invalid; 7632 } 7633 if ( aSign ) { 7634 if ( ( aExp | aSig0 | aSig1 ) == 0 ) return a; 7635 invalid: 7636 float_raise(float_flag_invalid, status); 7637 return float128_default_nan(status); 7638 } 7639 if ( aExp == 0 ) { 7640 if ( ( aSig0 | aSig1 ) == 0 ) return packFloat128( 0, 0, 0, 0 ); 7641 normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 ); 7642 } 7643 zExp = ( ( aExp - 0x3FFF )>>1 ) + 0x3FFE; 7644 aSig0 |= LIT64( 0x0001000000000000 ); 7645 zSig0 = estimateSqrt32( aExp, aSig0>>17 ); 7646 shortShift128Left( aSig0, aSig1, 13 - ( aExp & 1 ), &aSig0, &aSig1 ); 7647 zSig0 = estimateDiv128To64( aSig0, aSig1, zSig0<<32 ) + ( zSig0<<30 ); 7648 doubleZSig0 = zSig0<<1; 7649 mul64To128( zSig0, zSig0, &term0, &term1 ); 7650 sub128( aSig0, aSig1, term0, term1, &rem0, &rem1 ); 7651 while ( (int64_t) rem0 < 0 ) { 7652 --zSig0; 7653 doubleZSig0 -= 2; 7654 add128( rem0, rem1, zSig0>>63, doubleZSig0 | 1, &rem0, &rem1 ); 7655 } 7656 zSig1 = estimateDiv128To64( rem1, 0, doubleZSig0 ); 7657 if ( ( zSig1 & 0x1FFF ) <= 5 ) { 7658 if ( zSig1 == 0 ) zSig1 = 1; 7659 mul64To128( doubleZSig0, zSig1, &term1, &term2 ); 7660 sub128( rem1, 0, term1, term2, &rem1, &rem2 ); 7661 mul64To128( zSig1, zSig1, &term2, &term3 ); 7662 sub192( rem1, rem2, 0, 0, term2, term3, &rem1, &rem2, &rem3 ); 7663 while ( (int64_t) rem1 < 0 ) { 7664 --zSig1; 7665 shortShift128Left( 0, zSig1, 1, &term2, &term3 ); 7666 term3 |= 1; 7667 term2 |= doubleZSig0; 7668 add192( rem1, rem2, rem3, 0, term2, term3, &rem1, &rem2, &rem3 ); 7669 } 7670 zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 ); 7671 } 7672 shift128ExtraRightJamming( zSig0, zSig1, 0, 14, &zSig0, &zSig1, &zSig2 ); 7673 return roundAndPackFloat128(0, zExp, zSig0, zSig1, zSig2, status); 7674 7675 } 7676 7677 /*---------------------------------------------------------------------------- 7678 | Returns 1 if the quadruple-precision floating-point value `a' is equal to 7679 | the corresponding value `b', and 0 otherwise. The invalid exception is 7680 | raised if either operand is a NaN. Otherwise, the comparison is performed 7681 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 7682 *----------------------------------------------------------------------------*/ 7683 7684 int float128_eq(float128 a, float128 b, float_status *status) 7685 { 7686 7687 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7688 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7689 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7690 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7691 ) { 7692 float_raise(float_flag_invalid, status); 7693 return 0; 7694 } 7695 return 7696 ( a.low == b.low ) 7697 && ( ( a.high == b.high ) 7698 || ( ( a.low == 0 ) 7699 && ( (uint64_t) ( ( a.high | b.high )<<1 ) == 0 ) ) 7700 ); 7701 7702 } 7703 7704 /*---------------------------------------------------------------------------- 7705 | Returns 1 if the quadruple-precision floating-point value `a' is less than 7706 | or equal to the corresponding value `b', and 0 otherwise. The invalid 7707 | exception is raised if either operand is a NaN. The comparison is performed 7708 | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 7709 *----------------------------------------------------------------------------*/ 7710 7711 int float128_le(float128 a, float128 b, float_status *status) 7712 { 7713 flag aSign, bSign; 7714 7715 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7716 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7717 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7718 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7719 ) { 7720 float_raise(float_flag_invalid, status); 7721 return 0; 7722 } 7723 aSign = extractFloat128Sign( a ); 7724 bSign = extractFloat128Sign( b ); 7725 if ( aSign != bSign ) { 7726 return 7727 aSign 7728 || ( ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 7729 == 0 ); 7730 } 7731 return 7732 aSign ? le128( b.high, b.low, a.high, a.low ) 7733 : le128( a.high, a.low, b.high, b.low ); 7734 7735 } 7736 7737 /*---------------------------------------------------------------------------- 7738 | Returns 1 if the quadruple-precision floating-point value `a' is less than 7739 | the corresponding value `b', and 0 otherwise. The invalid exception is 7740 | raised if either operand is a NaN. The comparison is performed according 7741 | to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. 7742 *----------------------------------------------------------------------------*/ 7743 7744 int float128_lt(float128 a, float128 b, float_status *status) 7745 { 7746 flag aSign, bSign; 7747 7748 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7749 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7750 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7751 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7752 ) { 7753 float_raise(float_flag_invalid, status); 7754 return 0; 7755 } 7756 aSign = extractFloat128Sign( a ); 7757 bSign = extractFloat128Sign( b ); 7758 if ( aSign != bSign ) { 7759 return 7760 aSign 7761 && ( ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 7762 != 0 ); 7763 } 7764 return 7765 aSign ? lt128( b.high, b.low, a.high, a.low ) 7766 : lt128( a.high, a.low, b.high, b.low ); 7767 7768 } 7769 7770 /*---------------------------------------------------------------------------- 7771 | Returns 1 if the quadruple-precision floating-point values `a' and `b' cannot 7772 | be compared, and 0 otherwise. The invalid exception is raised if either 7773 | operand is a NaN. The comparison is performed according to the IEC/IEEE 7774 | Standard for Binary Floating-Point Arithmetic. 7775 *----------------------------------------------------------------------------*/ 7776 7777 int float128_unordered(float128 a, float128 b, float_status *status) 7778 { 7779 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7780 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7781 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7782 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7783 ) { 7784 float_raise(float_flag_invalid, status); 7785 return 1; 7786 } 7787 return 0; 7788 } 7789 7790 /*---------------------------------------------------------------------------- 7791 | Returns 1 if the quadruple-precision floating-point value `a' is equal to 7792 | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an 7793 | exception. The comparison is performed according to the IEC/IEEE Standard 7794 | for Binary Floating-Point Arithmetic. 7795 *----------------------------------------------------------------------------*/ 7796 7797 int float128_eq_quiet(float128 a, float128 b, float_status *status) 7798 { 7799 7800 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7801 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7802 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7803 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7804 ) { 7805 if (float128_is_signaling_nan(a, status) 7806 || float128_is_signaling_nan(b, status)) { 7807 float_raise(float_flag_invalid, status); 7808 } 7809 return 0; 7810 } 7811 return 7812 ( a.low == b.low ) 7813 && ( ( a.high == b.high ) 7814 || ( ( a.low == 0 ) 7815 && ( (uint64_t) ( ( a.high | b.high )<<1 ) == 0 ) ) 7816 ); 7817 7818 } 7819 7820 /*---------------------------------------------------------------------------- 7821 | Returns 1 if the quadruple-precision floating-point value `a' is less than 7822 | or equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not 7823 | cause an exception. Otherwise, the comparison is performed according to the 7824 | IEC/IEEE Standard for Binary Floating-Point Arithmetic. 7825 *----------------------------------------------------------------------------*/ 7826 7827 int float128_le_quiet(float128 a, float128 b, float_status *status) 7828 { 7829 flag aSign, bSign; 7830 7831 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7832 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7833 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7834 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7835 ) { 7836 if (float128_is_signaling_nan(a, status) 7837 || float128_is_signaling_nan(b, status)) { 7838 float_raise(float_flag_invalid, status); 7839 } 7840 return 0; 7841 } 7842 aSign = extractFloat128Sign( a ); 7843 bSign = extractFloat128Sign( b ); 7844 if ( aSign != bSign ) { 7845 return 7846 aSign 7847 || ( ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 7848 == 0 ); 7849 } 7850 return 7851 aSign ? le128( b.high, b.low, a.high, a.low ) 7852 : le128( a.high, a.low, b.high, b.low ); 7853 7854 } 7855 7856 /*---------------------------------------------------------------------------- 7857 | Returns 1 if the quadruple-precision floating-point value `a' is less than 7858 | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an 7859 | exception. Otherwise, the comparison is performed according to the IEC/IEEE 7860 | Standard for Binary Floating-Point Arithmetic. 7861 *----------------------------------------------------------------------------*/ 7862 7863 int float128_lt_quiet(float128 a, float128 b, float_status *status) 7864 { 7865 flag aSign, bSign; 7866 7867 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7868 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7869 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7870 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7871 ) { 7872 if (float128_is_signaling_nan(a, status) 7873 || float128_is_signaling_nan(b, status)) { 7874 float_raise(float_flag_invalid, status); 7875 } 7876 return 0; 7877 } 7878 aSign = extractFloat128Sign( a ); 7879 bSign = extractFloat128Sign( b ); 7880 if ( aSign != bSign ) { 7881 return 7882 aSign 7883 && ( ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) 7884 != 0 ); 7885 } 7886 return 7887 aSign ? lt128( b.high, b.low, a.high, a.low ) 7888 : lt128( a.high, a.low, b.high, b.low ); 7889 7890 } 7891 7892 /*---------------------------------------------------------------------------- 7893 | Returns 1 if the quadruple-precision floating-point values `a' and `b' cannot 7894 | be compared, and 0 otherwise. Quiet NaNs do not cause an exception. The 7895 | comparison is performed according to the IEC/IEEE Standard for Binary 7896 | Floating-Point Arithmetic. 7897 *----------------------------------------------------------------------------*/ 7898 7899 int float128_unordered_quiet(float128 a, float128 b, float_status *status) 7900 { 7901 if ( ( ( extractFloat128Exp( a ) == 0x7FFF ) 7902 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) 7903 || ( ( extractFloat128Exp( b ) == 0x7FFF ) 7904 && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) ) 7905 ) { 7906 if (float128_is_signaling_nan(a, status) 7907 || float128_is_signaling_nan(b, status)) { 7908 float_raise(float_flag_invalid, status); 7909 } 7910 return 1; 7911 } 7912 return 0; 7913 } 7914 7915 static inline int floatx80_compare_internal(floatx80 a, floatx80 b, 7916 int is_quiet, float_status *status) 7917 { 7918 flag aSign, bSign; 7919 7920 if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) { 7921 float_raise(float_flag_invalid, status); 7922 return float_relation_unordered; 7923 } 7924 if (( ( extractFloatx80Exp( a ) == 0x7fff ) && 7925 ( extractFloatx80Frac( a )<<1 ) ) || 7926 ( ( extractFloatx80Exp( b ) == 0x7fff ) && 7927 ( extractFloatx80Frac( b )<<1 ) )) { 7928 if (!is_quiet || 7929 floatx80_is_signaling_nan(a, status) || 7930 floatx80_is_signaling_nan(b, status)) { 7931 float_raise(float_flag_invalid, status); 7932 } 7933 return float_relation_unordered; 7934 } 7935 aSign = extractFloatx80Sign( a ); 7936 bSign = extractFloatx80Sign( b ); 7937 if ( aSign != bSign ) { 7938 7939 if ( ( ( (uint16_t) ( ( a.high | b.high ) << 1 ) ) == 0) && 7940 ( ( a.low | b.low ) == 0 ) ) { 7941 /* zero case */ 7942 return float_relation_equal; 7943 } else { 7944 return 1 - (2 * aSign); 7945 } 7946 } else { 7947 if (a.low == b.low && a.high == b.high) { 7948 return float_relation_equal; 7949 } else { 7950 return 1 - 2 * (aSign ^ ( lt128( a.high, a.low, b.high, b.low ) )); 7951 } 7952 } 7953 } 7954 7955 int floatx80_compare(floatx80 a, floatx80 b, float_status *status) 7956 { 7957 return floatx80_compare_internal(a, b, 0, status); 7958 } 7959 7960 int floatx80_compare_quiet(floatx80 a, floatx80 b, float_status *status) 7961 { 7962 return floatx80_compare_internal(a, b, 1, status); 7963 } 7964 7965 static inline int float128_compare_internal(float128 a, float128 b, 7966 int is_quiet, float_status *status) 7967 { 7968 flag aSign, bSign; 7969 7970 if (( ( extractFloat128Exp( a ) == 0x7fff ) && 7971 ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) || 7972 ( ( extractFloat128Exp( b ) == 0x7fff ) && 7973 ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )) { 7974 if (!is_quiet || 7975 float128_is_signaling_nan(a, status) || 7976 float128_is_signaling_nan(b, status)) { 7977 float_raise(float_flag_invalid, status); 7978 } 7979 return float_relation_unordered; 7980 } 7981 aSign = extractFloat128Sign( a ); 7982 bSign = extractFloat128Sign( b ); 7983 if ( aSign != bSign ) { 7984 if ( ( ( ( a.high | b.high )<<1 ) | a.low | b.low ) == 0 ) { 7985 /* zero case */ 7986 return float_relation_equal; 7987 } else { 7988 return 1 - (2 * aSign); 7989 } 7990 } else { 7991 if (a.low == b.low && a.high == b.high) { 7992 return float_relation_equal; 7993 } else { 7994 return 1 - 2 * (aSign ^ ( lt128( a.high, a.low, b.high, b.low ) )); 7995 } 7996 } 7997 } 7998 7999 int float128_compare(float128 a, float128 b, float_status *status) 8000 { 8001 return float128_compare_internal(a, b, 0, status); 8002 } 8003 8004 int float128_compare_quiet(float128 a, float128 b, float_status *status) 8005 { 8006 return float128_compare_internal(a, b, 1, status); 8007 } 8008 8009 floatx80 floatx80_scalbn(floatx80 a, int n, float_status *status) 8010 { 8011 flag aSign; 8012 int32_t aExp; 8013 uint64_t aSig; 8014 8015 if (floatx80_invalid_encoding(a)) { 8016 float_raise(float_flag_invalid, status); 8017 return floatx80_default_nan(status); 8018 } 8019 aSig = extractFloatx80Frac( a ); 8020 aExp = extractFloatx80Exp( a ); 8021 aSign = extractFloatx80Sign( a ); 8022 8023 if ( aExp == 0x7FFF ) { 8024 if ( aSig<<1 ) { 8025 return propagateFloatx80NaN(a, a, status); 8026 } 8027 return a; 8028 } 8029 8030 if (aExp == 0) { 8031 if (aSig == 0) { 8032 return a; 8033 } 8034 aExp++; 8035 } 8036 8037 if (n > 0x10000) { 8038 n = 0x10000; 8039 } else if (n < -0x10000) { 8040 n = -0x10000; 8041 } 8042 8043 aExp += n; 8044 return normalizeRoundAndPackFloatx80(status->floatx80_rounding_precision, 8045 aSign, aExp, aSig, 0, status); 8046 } 8047 8048 float128 float128_scalbn(float128 a, int n, float_status *status) 8049 { 8050 flag aSign; 8051 int32_t aExp; 8052 uint64_t aSig0, aSig1; 8053 8054 aSig1 = extractFloat128Frac1( a ); 8055 aSig0 = extractFloat128Frac0( a ); 8056 aExp = extractFloat128Exp( a ); 8057 aSign = extractFloat128Sign( a ); 8058 if ( aExp == 0x7FFF ) { 8059 if ( aSig0 | aSig1 ) { 8060 return propagateFloat128NaN(a, a, status); 8061 } 8062 return a; 8063 } 8064 if (aExp != 0) { 8065 aSig0 |= LIT64( 0x0001000000000000 ); 8066 } else if (aSig0 == 0 && aSig1 == 0) { 8067 return a; 8068 } else { 8069 aExp++; 8070 } 8071 8072 if (n > 0x10000) { 8073 n = 0x10000; 8074 } else if (n < -0x10000) { 8075 n = -0x10000; 8076 } 8077 8078 aExp += n - 1; 8079 return normalizeRoundAndPackFloat128( aSign, aExp, aSig0, aSig1 8080 , status); 8081 8082 } 8083 8084 static void __attribute__((constructor)) softfloat_init(void) 8085 { 8086 union_float64 ua, ub, uc, ur; 8087 8088 if (QEMU_NO_HARDFLOAT) { 8089 return; 8090 } 8091 /* 8092 * Test that the host's FMA is not obviously broken. For example, 8093 * glibc < 2.23 can perform an incorrect FMA on certain hosts; see 8094 * https://sourceware.org/bugzilla/show_bug.cgi?id=13304 8095 */ 8096 ua.s = 0x0020000000000001ULL; 8097 ub.s = 0x3ca0000000000000ULL; 8098 uc.s = 0x0020000000000000ULL; 8099 ur.h = fma(ua.h, ub.h, uc.h); 8100 if (ur.s != 0x0020000000000001ULL) { 8101 force_soft_fma = true; 8102 } 8103 } 8104