1 /* Definitions of floating-point access for GNU compiler. 2 Copyright (C) 1989, 1991, 1994, 1996, 1997, 1998, 1999, 3 2000, 2002, 2003, 2004, 2005, 2007, 2008 Free Software Foundation, Inc. 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 3, or (at your option) any later 10 version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #ifndef GCC_REAL_H 22 #define GCC_REAL_H 23 24 #ifndef GENERATOR_FILE 25 #include <gmp.h> 26 #include <mpfr.h> 27 #endif 28 #include "machmode.h" 29 30 /* An expanded form of the represented number. */ 31 32 /* Enumerate the special cases of numbers that we encounter. */ 33 enum real_value_class { 34 rvc_zero, 35 rvc_normal, 36 rvc_inf, 37 rvc_nan 38 }; 39 40 #define SIGNIFICAND_BITS (128 + HOST_BITS_PER_LONG) 41 #define EXP_BITS (32 - 6) 42 #define MAX_EXP ((1 << (EXP_BITS - 1)) - 1) 43 #define SIGSZ (SIGNIFICAND_BITS / HOST_BITS_PER_LONG) 44 #define SIG_MSB ((unsigned long)1 << (HOST_BITS_PER_LONG - 1)) 45 46 struct real_value GTY(()) 47 { 48 /* Use the same underlying type for all bit-fields, so as to make 49 sure they're packed together, otherwise REAL_VALUE_TYPE_SIZE will 50 be miscomputed. */ 51 unsigned int /* ENUM_BITFIELD (real_value_class) */ cl : 2; 52 unsigned int decimal : 1; 53 unsigned int sign : 1; 54 unsigned int signalling : 1; 55 unsigned int canonical : 1; 56 unsigned int uexp : EXP_BITS; 57 unsigned long sig[SIGSZ]; 58 }; 59 60 #define REAL_EXP(REAL) \ 61 ((int)((REAL)->uexp ^ (unsigned int)(1 << (EXP_BITS - 1))) \ 62 - (1 << (EXP_BITS - 1))) 63 #define SET_REAL_EXP(REAL, EXP) \ 64 ((REAL)->uexp = ((unsigned int)(EXP) & (unsigned int)((1 << EXP_BITS) - 1))) 65 66 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it 67 needs to be a macro. We do need to continue to have a structure tag 68 so that other headers can forward declare it. */ 69 #define REAL_VALUE_TYPE struct real_value 70 71 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in 72 consecutive "w" slots. Moreover, we've got to compute the number of "w" 73 slots at preprocessor time, which means we can't use sizeof. Guess. */ 74 75 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32) 76 #define REAL_WIDTH \ 77 (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \ 78 + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */ 79 80 /* Verify the guess. */ 81 extern char test_real_width 82 [sizeof(REAL_VALUE_TYPE) <= REAL_WIDTH*sizeof(HOST_WIDE_INT) ? 1 : -1]; 83 84 /* Calculate the format for CONST_DOUBLE. We need as many slots as 85 are necessary to overlay a REAL_VALUE_TYPE on them. This could be 86 as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE). 87 88 A number of places assume that there are always at least two 'w' 89 slots in a CONST_DOUBLE, so we provide them even if one would suffice. */ 90 91 #if REAL_WIDTH == 1 92 # define CONST_DOUBLE_FORMAT "ww" 93 #else 94 # if REAL_WIDTH == 2 95 # define CONST_DOUBLE_FORMAT "ww" 96 # else 97 # if REAL_WIDTH == 3 98 # define CONST_DOUBLE_FORMAT "www" 99 # else 100 # if REAL_WIDTH == 4 101 # define CONST_DOUBLE_FORMAT "wwww" 102 # else 103 # if REAL_WIDTH == 5 104 # define CONST_DOUBLE_FORMAT "wwwww" 105 # else 106 # if REAL_WIDTH == 6 107 # define CONST_DOUBLE_FORMAT "wwwwww" 108 # else 109 #error "REAL_WIDTH > 6 not supported" 110 # endif 111 # endif 112 # endif 113 # endif 114 # endif 115 #endif 116 117 118 /* Describes the properties of the specific target format in use. */ 119 struct real_format 120 { 121 /* Move to and from the target bytes. */ 122 void (*encode) (const struct real_format *, long *, 123 const REAL_VALUE_TYPE *); 124 void (*decode) (const struct real_format *, REAL_VALUE_TYPE *, 125 const long *); 126 127 /* The radix of the exponent and digits of the significand. */ 128 int b; 129 130 /* Size of the significand in digits of radix B. */ 131 int p; 132 133 /* Size of the significant of a NaN, in digits of radix B. */ 134 int pnan; 135 136 /* The minimum negative integer, x, such that b**(x-1) is normalized. */ 137 int emin; 138 139 /* The maximum integer, x, such that b**(x-1) is representable. */ 140 int emax; 141 142 /* The bit position of the sign bit, for determining whether a value 143 is positive/negative, or -1 for a complex encoding. */ 144 int signbit_ro; 145 146 /* The bit position of the sign bit, for changing the sign of a number, 147 or -1 for a complex encoding. */ 148 int signbit_rw; 149 150 /* Default rounding mode for operations on this format. */ 151 bool round_towards_zero; 152 bool has_sign_dependent_rounding; 153 154 /* Properties of the format. */ 155 bool has_nans; 156 bool has_inf; 157 bool has_denorm; 158 bool has_signed_zero; 159 bool qnan_msb_set; 160 bool canonical_nan_lsbs_set; 161 }; 162 163 164 /* The target format used for each floating point mode. 165 Float modes are followed by decimal float modes, with entries for 166 float modes indexed by (MODE - first float mode), and entries for 167 decimal float modes indexed by (MODE - first decimal float mode) + 168 the number of float modes. */ 169 extern const struct real_format * 170 real_format_for_mode[MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1 171 + MAX_MODE_DECIMAL_FLOAT - MIN_MODE_DECIMAL_FLOAT + 1]; 172 173 #define REAL_MODE_FORMAT(MODE) \ 174 (real_format_for_mode[DECIMAL_FLOAT_MODE_P (MODE) \ 175 ? (((MODE) - MIN_MODE_DECIMAL_FLOAT) \ 176 + (MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1)) \ 177 : ((MODE) - MIN_MODE_FLOAT)]) 178 179 #define FLOAT_MODE_FORMAT(MODE) \ 180 (REAL_MODE_FORMAT (SCALAR_FLOAT_MODE_P (MODE)? (MODE) \ 181 : GET_MODE_INNER (MODE))) 182 183 /* The following macro determines whether the floating point format is 184 composite, i.e. may contain non-consecutive mantissa bits, in which 185 case compile-time FP overflow may not model run-time overflow. */ 186 #define MODE_COMPOSITE_P(MODE) \ 187 (FLOAT_MODE_P (MODE) \ 188 && FLOAT_MODE_FORMAT (MODE)->pnan < FLOAT_MODE_FORMAT (MODE)->p) 189 190 /* Accessor macros for format properties. */ 191 #define MODE_HAS_NANS(MODE) \ 192 (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_nans) 193 #define MODE_HAS_INFINITIES(MODE) \ 194 (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_inf) 195 #define MODE_HAS_SIGNED_ZEROS(MODE) \ 196 (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_signed_zero) 197 #define MODE_HAS_SIGN_DEPENDENT_ROUNDING(MODE) \ 198 (FLOAT_MODE_P (MODE) \ 199 && FLOAT_MODE_FORMAT (MODE)->has_sign_dependent_rounding) 200 201 202 /* Declare functions in real.c. */ 203 204 /* Binary or unary arithmetic on tree_code. */ 205 extern bool real_arithmetic (REAL_VALUE_TYPE *, int, const REAL_VALUE_TYPE *, 206 const REAL_VALUE_TYPE *); 207 208 /* Compare reals by tree_code. */ 209 extern bool real_compare (int, const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *); 210 211 /* Determine whether a floating-point value X is infinite. */ 212 extern bool real_isinf (const REAL_VALUE_TYPE *); 213 214 /* Determine whether a floating-point value X is a NaN. */ 215 extern bool real_isnan (const REAL_VALUE_TYPE *); 216 217 /* Determine whether a floating-point value X is finite. */ 218 extern bool real_isfinite (const REAL_VALUE_TYPE *); 219 220 /* Determine whether a floating-point value X is negative. */ 221 extern bool real_isneg (const REAL_VALUE_TYPE *); 222 223 /* Determine whether a floating-point value X is minus zero. */ 224 extern bool real_isnegzero (const REAL_VALUE_TYPE *); 225 226 /* Compare two floating-point objects for bitwise identity. */ 227 extern bool real_identical (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *); 228 229 /* Extend or truncate to a new mode. */ 230 extern void real_convert (REAL_VALUE_TYPE *, enum machine_mode, 231 const REAL_VALUE_TYPE *); 232 233 /* Return true if truncating to NEW is exact. */ 234 extern bool exact_real_truncate (enum machine_mode, const REAL_VALUE_TYPE *); 235 236 /* Render R as a decimal floating point constant. */ 237 extern void real_to_decimal (char *, const REAL_VALUE_TYPE *, size_t, 238 size_t, int); 239 240 /* Render R as a decimal floating point constant, rounded so as to be 241 parsed back to the same value when interpreted in mode MODE. */ 242 extern void real_to_decimal_for_mode (char *, const REAL_VALUE_TYPE *, size_t, 243 size_t, int, enum machine_mode); 244 245 /* Render R as a hexadecimal floating point constant. */ 246 extern void real_to_hexadecimal (char *, const REAL_VALUE_TYPE *, 247 size_t, size_t, int); 248 249 /* Render R as an integer. */ 250 extern HOST_WIDE_INT real_to_integer (const REAL_VALUE_TYPE *); 251 extern void real_to_integer2 (HOST_WIDE_INT *, HOST_WIDE_INT *, 252 const REAL_VALUE_TYPE *); 253 254 /* Initialize R from a decimal or hexadecimal string. Return -1 if 255 the value underflows, +1 if overflows, and 0 otherwise. */ 256 extern int real_from_string (REAL_VALUE_TYPE *, const char *); 257 /* Wrapper to allow different internal representation for decimal floats. */ 258 extern void real_from_string3 (REAL_VALUE_TYPE *, const char *, enum machine_mode); 259 260 /* Initialize R from an integer pair HIGH/LOW. */ 261 extern void real_from_integer (REAL_VALUE_TYPE *, enum machine_mode, 262 unsigned HOST_WIDE_INT, HOST_WIDE_INT, int); 263 264 extern long real_to_target_fmt (long *, const REAL_VALUE_TYPE *, 265 const struct real_format *); 266 extern long real_to_target (long *, const REAL_VALUE_TYPE *, enum machine_mode); 267 268 extern void real_from_target_fmt (REAL_VALUE_TYPE *, const long *, 269 const struct real_format *); 270 extern void real_from_target (REAL_VALUE_TYPE *, const long *, 271 enum machine_mode); 272 273 extern void real_inf (REAL_VALUE_TYPE *); 274 275 extern bool real_nan (REAL_VALUE_TYPE *, const char *, int, enum machine_mode); 276 277 extern void real_maxval (REAL_VALUE_TYPE *, int, enum machine_mode); 278 279 extern void real_2expN (REAL_VALUE_TYPE *, int, enum machine_mode); 280 281 extern unsigned int real_hash (const REAL_VALUE_TYPE *); 282 283 284 /* Target formats defined in real.c. */ 285 extern const struct real_format ieee_single_format; 286 extern const struct real_format mips_single_format; 287 extern const struct real_format motorola_single_format; 288 extern const struct real_format spu_single_format; 289 extern const struct real_format ieee_double_format; 290 extern const struct real_format mips_double_format; 291 extern const struct real_format motorola_double_format; 292 extern const struct real_format ieee_extended_motorola_format; 293 extern const struct real_format ieee_extended_intel_96_format; 294 extern const struct real_format ieee_extended_intel_96_round_53_format; 295 extern const struct real_format ieee_extended_intel_128_format; 296 extern const struct real_format ibm_extended_format; 297 extern const struct real_format mips_extended_format; 298 extern const struct real_format ieee_quad_format; 299 extern const struct real_format mips_quad_format; 300 extern const struct real_format vax_f_format; 301 extern const struct real_format vax_d_format; 302 extern const struct real_format vax_g_format; 303 extern const struct real_format real_internal_format; 304 extern const struct real_format decimal_single_format; 305 extern const struct real_format decimal_double_format; 306 extern const struct real_format decimal_quad_format; 307 308 309 /* ====================================================================== */ 310 /* Crap. */ 311 312 #define REAL_ARITHMETIC(value, code, d1, d2) \ 313 real_arithmetic (&(value), code, &(d1), &(d2)) 314 315 #define REAL_VALUES_IDENTICAL(x, y) real_identical (&(x), &(y)) 316 #define REAL_VALUES_EQUAL(x, y) real_compare (EQ_EXPR, &(x), &(y)) 317 #define REAL_VALUES_LESS(x, y) real_compare (LT_EXPR, &(x), &(y)) 318 319 /* Determine whether a floating-point value X is infinite. */ 320 #define REAL_VALUE_ISINF(x) real_isinf (&(x)) 321 322 /* Determine whether a floating-point value X is a NaN. */ 323 #define REAL_VALUE_ISNAN(x) real_isnan (&(x)) 324 325 /* Determine whether a floating-point value X is negative. */ 326 #define REAL_VALUE_NEGATIVE(x) real_isneg (&(x)) 327 328 /* Determine whether a floating-point value X is minus zero. */ 329 #define REAL_VALUE_MINUS_ZERO(x) real_isnegzero (&(x)) 330 331 /* IN is a REAL_VALUE_TYPE. OUT is an array of longs. */ 332 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) \ 333 real_to_target (OUT, &(IN), \ 334 mode_for_size (LONG_DOUBLE_TYPE_SIZE, MODE_FLOAT, 0)) 335 336 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \ 337 real_to_target (OUT, &(IN), mode_for_size (64, MODE_FLOAT, 0)) 338 339 /* IN is a REAL_VALUE_TYPE. OUT is a long. */ 340 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \ 341 ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_FLOAT, 0))) 342 343 #define REAL_VALUE_FROM_INT(r, lo, hi, mode) \ 344 real_from_integer (&(r), mode, lo, hi, 0) 345 346 #define REAL_VALUE_FROM_UNSIGNED_INT(r, lo, hi, mode) \ 347 real_from_integer (&(r), mode, lo, hi, 1) 348 349 /* Real values to IEEE 754 decimal floats. */ 350 351 /* IN is a REAL_VALUE_TYPE. OUT is an array of longs. */ 352 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \ 353 real_to_target (OUT, &(IN), mode_for_size (128, MODE_DECIMAL_FLOAT, 0)) 354 355 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \ 356 real_to_target (OUT, &(IN), mode_for_size (64, MODE_DECIMAL_FLOAT, 0)) 357 358 /* IN is a REAL_VALUE_TYPE. OUT is a long. */ 359 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \ 360 ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_DECIMAL_FLOAT, 0))) 361 362 extern REAL_VALUE_TYPE real_value_truncate (enum machine_mode, 363 REAL_VALUE_TYPE); 364 365 #define REAL_VALUE_TO_INT(plow, phigh, r) \ 366 real_to_integer2 (plow, phigh, &(r)) 367 368 extern REAL_VALUE_TYPE real_arithmetic2 (int, const REAL_VALUE_TYPE *, 369 const REAL_VALUE_TYPE *); 370 371 #define REAL_VALUE_NEGATE(X) \ 372 real_arithmetic2 (NEGATE_EXPR, &(X), NULL) 373 374 #define REAL_VALUE_ABS(X) \ 375 real_arithmetic2 (ABS_EXPR, &(X), NULL) 376 377 extern int significand_size (enum machine_mode); 378 379 extern REAL_VALUE_TYPE real_from_string2 (const char *, enum machine_mode); 380 381 #define REAL_VALUE_ATOF(s, m) \ 382 real_from_string2 (s, m) 383 384 #define CONST_DOUBLE_ATOF(s, m) \ 385 CONST_DOUBLE_FROM_REAL_VALUE (real_from_string2 (s, m), m) 386 387 #define REAL_VALUE_FIX(r) \ 388 real_to_integer (&(r)) 389 390 /* ??? Not quite right. */ 391 #define REAL_VALUE_UNSIGNED_FIX(r) \ 392 real_to_integer (&(r)) 393 394 /* ??? These were added for Paranoia support. */ 395 396 /* Return floor log2(R). */ 397 extern int real_exponent (const REAL_VALUE_TYPE *); 398 399 /* R = A * 2**EXP. */ 400 extern void real_ldexp (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *, int); 401 402 /* **** End of software floating point emulator interface macros **** */ 403 404 /* Constant real values 0, 1, 2, -1 and 0.5. */ 406 407 extern REAL_VALUE_TYPE dconst0; 408 extern REAL_VALUE_TYPE dconst1; 409 extern REAL_VALUE_TYPE dconst2; 410 extern REAL_VALUE_TYPE dconstm1; 411 extern REAL_VALUE_TYPE dconsthalf; 412 413 #define dconst_e() (*dconst_e_ptr ()) 414 #define dconst_third() (*dconst_third_ptr ()) 415 #define dconst_sqrt2() (*dconst_sqrt2_ptr ()) 416 417 /* Function to return the real value special constant 'e'. */ 418 extern const REAL_VALUE_TYPE * dconst_e_ptr (void); 419 420 /* Returns the special REAL_VALUE_TYPE corresponding to 1/3. */ 421 extern const REAL_VALUE_TYPE * dconst_third_ptr (void); 422 423 /* Returns the special REAL_VALUE_TYPE corresponding to sqrt(2). */ 424 extern const REAL_VALUE_TYPE * dconst_sqrt2_ptr (void); 425 426 /* Function to return a real value (not a tree node) 427 from a given integer constant. */ 428 REAL_VALUE_TYPE real_value_from_int_cst (const_tree, const_tree); 429 430 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents. */ 431 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from) \ 432 ((to) = *CONST_DOUBLE_REAL_VALUE (from)) 433 434 /* Return a CONST_DOUBLE with value R and mode M. */ 435 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) \ 436 const_double_from_real_value (r, m) 437 extern rtx const_double_from_real_value (REAL_VALUE_TYPE, enum machine_mode); 438 439 /* Replace R by 1/R in the given machine mode, if the result is exact. */ 440 extern bool exact_real_inverse (enum machine_mode, REAL_VALUE_TYPE *); 441 442 /* Return true if arithmetic on values in IMODE that were promoted 443 from values in TMODE is equivalent to direct arithmetic on values 444 in TMODE. */ 445 bool real_can_shorten_arithmetic (enum machine_mode, enum machine_mode); 446 447 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node. */ 448 extern tree build_real (tree, REAL_VALUE_TYPE); 449 450 /* Calculate R as the square root of X in the given machine mode. */ 451 extern bool real_sqrt (REAL_VALUE_TYPE *, enum machine_mode, 452 const REAL_VALUE_TYPE *); 453 454 /* Calculate R as X raised to the integer exponent N in mode MODE. */ 455 extern bool real_powi (REAL_VALUE_TYPE *, enum machine_mode, 456 const REAL_VALUE_TYPE *, HOST_WIDE_INT); 457 458 /* Standard round to integer value functions. */ 459 extern void real_trunc (REAL_VALUE_TYPE *, enum machine_mode, 460 const REAL_VALUE_TYPE *); 461 extern void real_floor (REAL_VALUE_TYPE *, enum machine_mode, 462 const REAL_VALUE_TYPE *); 463 extern void real_ceil (REAL_VALUE_TYPE *, enum machine_mode, 464 const REAL_VALUE_TYPE *); 465 extern void real_round (REAL_VALUE_TYPE *, enum machine_mode, 466 const REAL_VALUE_TYPE *); 467 468 /* Set the sign of R to the sign of X. */ 469 extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *); 470 471 #ifndef GENERATOR_FILE 472 /* Convert between MPFR and REAL_VALUE_TYPE. The caller is 473 responsible for initializing and clearing the MPFR parameter. */ 474 475 extern void real_from_mpfr (REAL_VALUE_TYPE *, mpfr_srcptr, tree, mp_rnd_t); 476 extern void mpfr_from_real (mpfr_ptr, const REAL_VALUE_TYPE *, mp_rnd_t); 477 #endif 478 479 /* Check whether the real constant value given is an integer. */ 480 extern bool real_isinteger (const REAL_VALUE_TYPE *c, enum machine_mode mode); 481 482 /* Write into BUF the maximum representable finite floating-point 483 number, (1 - b**-p) * b**emax for a given FP format FMT as a hex 484 float string. BUF must be large enough to contain the result. */ 485 extern void get_max_float (const struct real_format *, char *, size_t); 486 #endif /* ! GCC_REAL_H */ 487
