1 /* Software floating-point emulation. 2 Copyright (C) 1997-2015 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 */ 355