xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame] | 1 | /* Software floating-point emulation. |
| 2 | Copyright (C) 1997-2016 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 4 | Contributed by Richard Henderson (rth@cygnus.com), |
| 5 | Jakub Jelinek (jj@ultra.linux.cz), |
| 6 | David S. Miller (davem@redhat.com) and |
| 7 | Peter Maydell (pmaydell@chiark.greenend.org.uk). |
| 8 | |
| 9 | The GNU C Library is free software; you can redistribute it and/or |
| 10 | modify it under the terms of the GNU Lesser General Public |
| 11 | License as published by the Free Software Foundation; either |
| 12 | version 2.1 of the License, or (at your option) any later version. |
| 13 | |
| 14 | In addition to the permissions in the GNU Lesser General Public |
| 15 | License, the Free Software Foundation gives you unlimited |
| 16 | permission to link the compiled version of this file into |
| 17 | combinations with other programs, and to distribute those |
| 18 | combinations without any restriction coming from the use of this |
| 19 | file. (The Lesser General Public License restrictions do apply in |
| 20 | other respects; for example, they cover modification of the file, |
| 21 | and distribution when not linked into a combine executable.) |
| 22 | |
| 23 | The GNU C Library is distributed in the hope that it will be useful, |
| 24 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 25 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 26 | Lesser General Public License for more details. |
| 27 | |
| 28 | You should have received a copy of the GNU Lesser General Public |
| 29 | License along with the GNU C Library; if not, see |
| 30 | <http://www.gnu.org/licenses/>. */ |
| 31 | |
| 32 | #ifndef SOFT_FP_H |
| 33 | #define SOFT_FP_H 1 |
| 34 | |
| 35 | #ifdef _LIBC |
| 36 | # include <sfp-machine.h> |
| 37 | #elif defined __KERNEL__ |
| 38 | /* The Linux kernel uses asm/ names for architecture-specific |
| 39 | files. */ |
| 40 | # include <asm/sfp-machine.h> |
| 41 | #else |
| 42 | # include "sfp-machine.h" |
| 43 | #endif |
| 44 | |
| 45 | /* Allow sfp-machine to have its own byte order definitions. */ |
| 46 | #ifndef __BYTE_ORDER |
| 47 | # ifdef _LIBC |
| 48 | # include <endian.h> |
| 49 | # else |
| 50 | # error "endianness not defined by sfp-machine.h" |
| 51 | # endif |
| 52 | #endif |
| 53 | |
| 54 | /* For unreachable default cases in switch statements over bitwise OR |
| 55 | of FP_CLS_* values. */ |
| 56 | #if (defined __GNUC__ \ |
| 57 | && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5))) |
| 58 | # define _FP_UNREACHABLE __builtin_unreachable () |
| 59 | #else |
| 60 | # define _FP_UNREACHABLE abort () |
| 61 | #endif |
| 62 | |
| 63 | #if ((defined __GNUC__ \ |
| 64 | && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))) \ |
| 65 | || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L)) |
| 66 | # define _FP_STATIC_ASSERT(expr, msg) \ |
| 67 | _Static_assert ((expr), msg) |
| 68 | #else |
| 69 | # define _FP_STATIC_ASSERT(expr, msg) \ |
| 70 | extern int (*__Static_assert_function (void)) \ |
| 71 | [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })] |
| 72 | #endif |
| 73 | |
| 74 | /* In the Linux kernel, some architectures have a single function that |
| 75 | uses different kinds of unpacking and packing depending on the |
| 76 | instruction being emulated, meaning it is not readily visible to |
| 77 | the compiler that variables from _FP_DECL and _FP_FRAC_DECL_* |
| 78 | macros are only used in cases where they were initialized. */ |
| 79 | #ifdef __KERNEL__ |
| 80 | # define _FP_ZERO_INIT = 0 |
| 81 | #else |
| 82 | # define _FP_ZERO_INIT |
| 83 | #endif |
| 84 | |
| 85 | #define _FP_WORKBITS 3 |
| 86 | #define _FP_WORK_LSB ((_FP_W_TYPE) 1 << 3) |
| 87 | #define _FP_WORK_ROUND ((_FP_W_TYPE) 1 << 2) |
| 88 | #define _FP_WORK_GUARD ((_FP_W_TYPE) 1 << 1) |
| 89 | #define _FP_WORK_STICKY ((_FP_W_TYPE) 1 << 0) |
| 90 | |
| 91 | #ifndef FP_RND_NEAREST |
| 92 | # define FP_RND_NEAREST 0 |
| 93 | # define FP_RND_ZERO 1 |
| 94 | # define FP_RND_PINF 2 |
| 95 | # define FP_RND_MINF 3 |
| 96 | #endif |
| 97 | #ifndef FP_ROUNDMODE |
| 98 | # define FP_ROUNDMODE FP_RND_NEAREST |
| 99 | #endif |
| 100 | |
| 101 | /* By default don't care about exceptions. */ |
| 102 | #ifndef FP_EX_INVALID |
| 103 | # define FP_EX_INVALID 0 |
| 104 | #endif |
| 105 | #ifndef FP_EX_OVERFLOW |
| 106 | # define FP_EX_OVERFLOW 0 |
| 107 | #endif |
| 108 | #ifndef FP_EX_UNDERFLOW |
| 109 | # define FP_EX_UNDERFLOW 0 |
| 110 | #endif |
| 111 | #ifndef FP_EX_DIVZERO |
| 112 | # define FP_EX_DIVZERO 0 |
| 113 | #endif |
| 114 | #ifndef FP_EX_INEXACT |
| 115 | # define FP_EX_INEXACT 0 |
| 116 | #endif |
| 117 | #ifndef FP_EX_DENORM |
| 118 | # define FP_EX_DENORM 0 |
| 119 | #endif |
| 120 | |
| 121 | /* Sub-exceptions of "invalid". */ |
| 122 | /* Signaling NaN operand. */ |
| 123 | #ifndef FP_EX_INVALID_SNAN |
| 124 | # define FP_EX_INVALID_SNAN 0 |
| 125 | #endif |
| 126 | /* Inf * 0. */ |
| 127 | #ifndef FP_EX_INVALID_IMZ |
| 128 | # define FP_EX_INVALID_IMZ 0 |
| 129 | #endif |
| 130 | /* fma (Inf, 0, c). */ |
| 131 | #ifndef FP_EX_INVALID_IMZ_FMA |
| 132 | # define FP_EX_INVALID_IMZ_FMA 0 |
| 133 | #endif |
| 134 | /* Inf - Inf. */ |
| 135 | #ifndef FP_EX_INVALID_ISI |
| 136 | # define FP_EX_INVALID_ISI 0 |
| 137 | #endif |
| 138 | /* 0 / 0. */ |
| 139 | #ifndef FP_EX_INVALID_ZDZ |
| 140 | # define FP_EX_INVALID_ZDZ 0 |
| 141 | #endif |
| 142 | /* Inf / Inf. */ |
| 143 | #ifndef FP_EX_INVALID_IDI |
| 144 | # define FP_EX_INVALID_IDI 0 |
| 145 | #endif |
| 146 | /* sqrt (negative). */ |
| 147 | #ifndef FP_EX_INVALID_SQRT |
| 148 | # define FP_EX_INVALID_SQRT 0 |
| 149 | #endif |
| 150 | /* Invalid conversion to integer. */ |
| 151 | #ifndef FP_EX_INVALID_CVI |
| 152 | # define FP_EX_INVALID_CVI 0 |
| 153 | #endif |
| 154 | /* Invalid comparison. */ |
| 155 | #ifndef FP_EX_INVALID_VC |
| 156 | # define FP_EX_INVALID_VC 0 |
| 157 | #endif |
| 158 | |
| 159 | /* _FP_STRUCT_LAYOUT may be defined as an attribute to determine the |
| 160 | struct layout variant used for structures where bit-fields are used |
| 161 | to access specific parts of binary floating-point numbers. This is |
| 162 | required for systems where the default ABI uses struct layout with |
| 163 | differences in how consecutive bit-fields are laid out from the |
| 164 | default expected by soft-fp. */ |
| 165 | #ifndef _FP_STRUCT_LAYOUT |
| 166 | # define _FP_STRUCT_LAYOUT |
| 167 | #endif |
| 168 | |
| 169 | #ifdef _FP_DECL_EX |
| 170 | # define FP_DECL_EX \ |
| 171 | int _fex = 0; \ |
| 172 | _FP_DECL_EX |
| 173 | #else |
| 174 | # define FP_DECL_EX int _fex = 0 |
| 175 | #endif |
| 176 | |
| 177 | /* Initialize any machine-specific state used in FP_ROUNDMODE, |
| 178 | FP_TRAPPING_EXCEPTIONS or FP_HANDLE_EXCEPTIONS. */ |
| 179 | #ifndef FP_INIT_ROUNDMODE |
| 180 | # define FP_INIT_ROUNDMODE do {} while (0) |
| 181 | #endif |
| 182 | |
| 183 | /* Initialize any machine-specific state used in |
| 184 | FP_TRAPPING_EXCEPTIONS or FP_HANDLE_EXCEPTIONS. */ |
| 185 | #ifndef FP_INIT_TRAPPING_EXCEPTIONS |
| 186 | # define FP_INIT_TRAPPING_EXCEPTIONS FP_INIT_ROUNDMODE |
| 187 | #endif |
| 188 | |
| 189 | /* Initialize any machine-specific state used in |
| 190 | FP_HANDLE_EXCEPTIONS. */ |
| 191 | #ifndef FP_INIT_EXCEPTIONS |
| 192 | # define FP_INIT_EXCEPTIONS FP_INIT_TRAPPING_EXCEPTIONS |
| 193 | #endif |
| 194 | |
| 195 | #ifndef FP_HANDLE_EXCEPTIONS |
| 196 | # define FP_HANDLE_EXCEPTIONS do {} while (0) |
| 197 | #endif |
| 198 | |
| 199 | /* Whether to flush subnormal inputs to zero with the same sign. */ |
| 200 | #ifndef FP_DENORM_ZERO |
| 201 | # define FP_DENORM_ZERO 0 |
| 202 | #endif |
| 203 | |
| 204 | #ifndef FP_INHIBIT_RESULTS |
| 205 | /* By default we write the results always. |
| 206 | sfp-machine may override this and e.g. |
| 207 | check if some exceptions are unmasked |
| 208 | and inhibit it in such a case. */ |
| 209 | # define FP_INHIBIT_RESULTS 0 |
| 210 | #endif |
| 211 | |
| 212 | #define FP_SET_EXCEPTION(ex) \ |
| 213 | _fex |= (ex) |
| 214 | |
| 215 | #define FP_CUR_EXCEPTIONS \ |
| 216 | (_fex) |
| 217 | |
| 218 | #ifndef FP_TRAPPING_EXCEPTIONS |
| 219 | # define FP_TRAPPING_EXCEPTIONS 0 |
| 220 | #endif |
| 221 | |
| 222 | /* A file using soft-fp may define FP_NO_EXCEPTIONS before including |
| 223 | soft-fp.h to indicate that, although a macro used there could raise |
| 224 | exceptions, or do rounding and potentially thereby raise |
| 225 | exceptions, for some arguments, for the particular arguments used |
| 226 | in that file no exceptions or rounding can occur. Such a file |
| 227 | should not itself use macros relating to handling exceptions and |
| 228 | rounding modes; this is only for indirect uses (in particular, in |
| 229 | _FP_FROM_INT and the macros it calls). */ |
| 230 | #ifdef FP_NO_EXCEPTIONS |
| 231 | |
| 232 | # undef FP_SET_EXCEPTION |
| 233 | # define FP_SET_EXCEPTION(ex) do {} while (0) |
| 234 | |
| 235 | # undef FP_CUR_EXCEPTIONS |
| 236 | # define FP_CUR_EXCEPTIONS 0 |
| 237 | |
| 238 | # undef FP_TRAPPING_EXCEPTIONS |
| 239 | # define FP_TRAPPING_EXCEPTIONS 0 |
| 240 | |
| 241 | # undef FP_ROUNDMODE |
| 242 | # define FP_ROUNDMODE FP_RND_ZERO |
| 243 | |
| 244 | # undef _FP_TININESS_AFTER_ROUNDING |
| 245 | # define _FP_TININESS_AFTER_ROUNDING 0 |
| 246 | |
| 247 | #endif |
| 248 | |
| 249 | /* A file using soft-fp may define FP_NO_EXACT_UNDERFLOW before |
| 250 | including soft-fp.h to indicate that, although a macro used there |
| 251 | could allow for the case of exact underflow requiring the underflow |
| 252 | exception to be raised if traps are enabled, for the particular |
| 253 | arguments used in that file no exact underflow can occur. */ |
| 254 | #ifdef FP_NO_EXACT_UNDERFLOW |
| 255 | # undef FP_TRAPPING_EXCEPTIONS |
| 256 | # define FP_TRAPPING_EXCEPTIONS 0 |
| 257 | #endif |
| 258 | |
| 259 | #define _FP_ROUND_NEAREST(wc, X) \ |
| 260 | do \ |
| 261 | { \ |
| 262 | if ((_FP_FRAC_LOW_##wc (X) & 15) != _FP_WORK_ROUND) \ |
| 263 | _FP_FRAC_ADDI_##wc (X, _FP_WORK_ROUND); \ |
| 264 | } \ |
| 265 | while (0) |
| 266 | |
| 267 | #define _FP_ROUND_ZERO(wc, X) (void) 0 |
| 268 | |
| 269 | #define _FP_ROUND_PINF(wc, X) \ |
| 270 | do \ |
| 271 | { \ |
| 272 | if (!X##_s && (_FP_FRAC_LOW_##wc (X) & 7)) \ |
| 273 | _FP_FRAC_ADDI_##wc (X, _FP_WORK_LSB); \ |
| 274 | } \ |
| 275 | while (0) |
| 276 | |
| 277 | #define _FP_ROUND_MINF(wc, X) \ |
| 278 | do \ |
| 279 | { \ |
| 280 | if (X##_s && (_FP_FRAC_LOW_##wc (X) & 7)) \ |
| 281 | _FP_FRAC_ADDI_##wc (X, _FP_WORK_LSB); \ |
| 282 | } \ |
| 283 | while (0) |
| 284 | |
| 285 | #define _FP_ROUND(wc, X) \ |
| 286 | do \ |
| 287 | { \ |
| 288 | if (_FP_FRAC_LOW_##wc (X) & 7) \ |
| 289 | { \ |
| 290 | FP_SET_EXCEPTION (FP_EX_INEXACT); \ |
| 291 | switch (FP_ROUNDMODE) \ |
| 292 | { \ |
| 293 | case FP_RND_NEAREST: \ |
| 294 | _FP_ROUND_NEAREST (wc, X); \ |
| 295 | break; \ |
| 296 | case FP_RND_ZERO: \ |
| 297 | _FP_ROUND_ZERO (wc, X); \ |
| 298 | break; \ |
| 299 | case FP_RND_PINF: \ |
| 300 | _FP_ROUND_PINF (wc, X); \ |
| 301 | break; \ |
| 302 | case FP_RND_MINF: \ |
| 303 | _FP_ROUND_MINF (wc, X); \ |
| 304 | break; \ |
| 305 | } \ |
| 306 | } \ |
| 307 | } \ |
| 308 | while (0) |
| 309 | |
| 310 | #define FP_CLS_NORMAL 0 |
| 311 | #define FP_CLS_ZERO 1 |
| 312 | #define FP_CLS_INF 2 |
| 313 | #define FP_CLS_NAN 3 |
| 314 | |
| 315 | #define _FP_CLS_COMBINE(x, y) (((x) << 2) | (y)) |
| 316 | |
| 317 | #include "op-1.h" |
| 318 | #include "op-2.h" |
| 319 | #include "op-4.h" |
| 320 | #include "op-8.h" |
| 321 | #include "op-common.h" |
| 322 | |
| 323 | /* Sigh. Silly things longlong.h needs. */ |
| 324 | #define UWtype _FP_W_TYPE |
| 325 | #define W_TYPE_SIZE _FP_W_TYPE_SIZE |
| 326 | |
| 327 | typedef int QItype __attribute__ ((mode (QI))); |
| 328 | typedef int SItype __attribute__ ((mode (SI))); |
| 329 | typedef int DItype __attribute__ ((mode (DI))); |
| 330 | typedef unsigned int UQItype __attribute__ ((mode (QI))); |
| 331 | typedef unsigned int USItype __attribute__ ((mode (SI))); |
| 332 | typedef unsigned int UDItype __attribute__ ((mode (DI))); |
| 333 | #if _FP_W_TYPE_SIZE == 32 |
| 334 | typedef unsigned int UHWtype __attribute__ ((mode (HI))); |
| 335 | #elif _FP_W_TYPE_SIZE == 64 |
| 336 | typedef USItype UHWtype; |
| 337 | #endif |
| 338 | |
| 339 | #ifndef CMPtype |
| 340 | # define CMPtype int |
| 341 | #endif |
| 342 | |
| 343 | #define SI_BITS (__CHAR_BIT__ * (int) sizeof (SItype)) |
| 344 | #define DI_BITS (__CHAR_BIT__ * (int) sizeof (DItype)) |
| 345 | |
| 346 | #ifndef umul_ppmm |
| 347 | # ifdef _LIBC |
| 348 | # include <stdlib/longlong.h> |
| 349 | # else |
| 350 | # include "longlong.h" |
| 351 | # endif |
| 352 | #endif |
| 353 | |
| 354 | #endif /* !SOFT_FP_H */ |