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 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 2, 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 COPYING. If not, write to the Free 19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 20 02110-1301, USA. */ 21 22 #ifndef GCC_REAL_H 23 #define GCC_REAL_H 24 25 #include "machmode.h" 26 27 /* An expanded form of the represented number. */ 28 29 /* Enumerate the special cases of numbers that we encounter. */ 30 enum real_value_class { 31 rvc_zero, 32 rvc_normal, 33 rvc_inf, 34 rvc_nan 35 }; 36 37 #define SIGNIFICAND_BITS (128 + HOST_BITS_PER_LONG) 38 #define EXP_BITS (32 - 6) 39 #define MAX_EXP ((1 << (EXP_BITS - 1)) - 1) 40 #define SIGSZ (SIGNIFICAND_BITS / HOST_BITS_PER_LONG) 41 #define SIG_MSB ((unsigned long)1 << (HOST_BITS_PER_LONG - 1)) 42 43 struct real_value GTY(()) 44 { 45 /* Use the same underlying type for all bit-fields, so as to make 46 sure they're packed together, otherwise REAL_VALUE_TYPE_SIZE will 47 be miscomputed. */ 48 unsigned int /* ENUM_BITFIELD (real_value_class) */ cl : 2; 49 unsigned int decimal : 1; 50 unsigned int sign : 1; 51 unsigned int signalling : 1; 52 unsigned int canonical : 1; 53 unsigned int uexp : EXP_BITS; 54 unsigned long sig[SIGSZ]; 55 }; 56 57 #define REAL_EXP(REAL) \ 58 ((int)((REAL)->uexp ^ (unsigned int)(1 << (EXP_BITS - 1))) \ 59 - (1 << (EXP_BITS - 1))) 60 #define SET_REAL_EXP(REAL, EXP) \ 61 ((REAL)->uexp = ((unsigned int)(EXP) & (unsigned int)((1 << EXP_BITS) - 1))) 62 63 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it 64 needs to be a macro. We do need to continue to have a structure tag 65 so that other headers can forward declare it. */ 66 #define REAL_VALUE_TYPE struct real_value 67 68 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in 69 consecutive "w" slots. Moreover, we've got to compute the number of "w" 70 slots at preprocessor time, which means we can't use sizeof. Guess. */ 71 72 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32) 73 #define REAL_WIDTH \ 74 (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \ 75 + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */ 76 77 /* Verify the guess. */ 78 extern char test_real_width 79 [sizeof(REAL_VALUE_TYPE) <= REAL_WIDTH*sizeof(HOST_WIDE_INT) ? 1 : -1]; 80 81 /* Calculate the format for CONST_DOUBLE. We need as many slots as 82 are necessary to overlay a REAL_VALUE_TYPE on them. This could be 83 as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE). 84 85 A number of places assume that there are always at least two 'w' 86 slots in a CONST_DOUBLE, so we provide them even if one would suffice. */ 87 88 #if REAL_WIDTH == 1 89 # define CONST_DOUBLE_FORMAT "ww" 90 #else 91 # if REAL_WIDTH == 2 92 # define CONST_DOUBLE_FORMAT "ww" 93 # else 94 # if REAL_WIDTH == 3 95 # define CONST_DOUBLE_FORMAT "www" 96 # else 97 # if REAL_WIDTH == 4 98 # define CONST_DOUBLE_FORMAT "wwww" 99 # else 100 # if REAL_WIDTH == 5 101 # define CONST_DOUBLE_FORMAT "wwwww" 102 # else 103 # if REAL_WIDTH == 6 104 # define CONST_DOUBLE_FORMAT "wwwwww" 105 # else 106 #error "REAL_WIDTH > 6 not supported" 107 # endif 108 # endif 109 # endif 110 # endif 111 # endif 112 #endif 113 114 115 /* Describes the properties of the specific target format in use. */ 116 struct real_format 117 { 118 /* Move to and from the target bytes. */ 119 void (*encode) (const struct real_format *, long *, 120 const REAL_VALUE_TYPE *); 121 void (*decode) (const struct real_format *, REAL_VALUE_TYPE *, 122 const long *); 123 124 /* The radix of the exponent and digits of the significand. */ 125 int b; 126 127 /* log2(b). */ 128 int log2_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 /* Properties of the format. */ 151 bool has_nans; 152 bool has_inf; 153 bool has_denorm; 154 bool has_signed_zero; 155 bool qnan_msb_set; 156 }; 157 158 159 /* The target format used for each floating point mode. 160 Float modes are followed by decimal float modes, with entries for 161 float modes indexed by (MODE - first float mode), and entries for 162 decimal float modes indexed by (MODE - first decimal float mode) + 163 the number of float modes. */ 164 extern const struct real_format * 165 real_format_for_mode[MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1 166 + MAX_MODE_DECIMAL_FLOAT - MIN_MODE_DECIMAL_FLOAT + 1]; 167 168 #define REAL_MODE_FORMAT(MODE) \ 169 (real_format_for_mode[DECIMAL_FLOAT_MODE_P (MODE) \ 170 ? ((MODE - MIN_MODE_DECIMAL_FLOAT) \ 171 + (MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1)) \ 172 : (MODE - MIN_MODE_FLOAT)]) 173 174 /* The following macro determines whether the floating point format is 175 composite, i.e. may contain non-consecutive mantissa bits, in which 176 case compile-time FP overflow may not model run-time overflow. */ 177 #define REAL_MODE_FORMAT_COMPOSITE_P(MODE) \ 178 ((REAL_MODE_FORMAT(MODE))->pnan < (REAL_MODE_FORMAT (MODE))->p) 179 180 /* Declare functions in real.c. */ 181 182 /* Binary or unary arithmetic on tree_code. */ 183 extern bool real_arithmetic (REAL_VALUE_TYPE *, int, const REAL_VALUE_TYPE *, 184 const REAL_VALUE_TYPE *); 185 186 /* Compare reals by tree_code. */ 187 extern bool real_compare (int, const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *); 188 189 /* Determine whether a floating-point value X is infinite. */ 190 extern bool real_isinf (const REAL_VALUE_TYPE *); 191 192 /* Determine whether a floating-point value X is a NaN. */ 193 extern bool real_isnan (const REAL_VALUE_TYPE *); 194 195 /* Determine whether a floating-point value X is negative. */ 196 extern bool real_isneg (const REAL_VALUE_TYPE *); 197 198 /* Determine whether a floating-point value X is minus zero. */ 199 extern bool real_isnegzero (const REAL_VALUE_TYPE *); 200 201 /* Compare two floating-point objects for bitwise identity. */ 202 extern bool real_identical (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *); 203 204 /* Extend or truncate to a new mode. */ 205 extern void real_convert (REAL_VALUE_TYPE *, enum machine_mode, 206 const REAL_VALUE_TYPE *); 207 208 /* Return true if truncating to NEW is exact. */ 209 extern bool exact_real_truncate (enum machine_mode, const REAL_VALUE_TYPE *); 210 211 /* Render R as a decimal floating point constant. */ 212 extern void real_to_decimal (char *, const REAL_VALUE_TYPE *, size_t, 213 size_t, int); 214 215 /* Render R as a hexadecimal floating point constant. */ 216 extern void real_to_hexadecimal (char *, const REAL_VALUE_TYPE *, 217 size_t, size_t, int); 218 219 /* Render R as an integer. */ 220 extern HOST_WIDE_INT real_to_integer (const REAL_VALUE_TYPE *); 221 extern void real_to_integer2 (HOST_WIDE_INT *, HOST_WIDE_INT *, 222 const REAL_VALUE_TYPE *); 223 224 /* Initialize R from a decimal or hexadecimal string. */ 225 extern void real_from_string (REAL_VALUE_TYPE *, const char *); 226 /* Wrapper to allow different internal representation for decimal floats. */ 227 extern void real_from_string3 (REAL_VALUE_TYPE *, const char *, enum machine_mode); 228 229 /* Initialize R from an integer pair HIGH/LOW. */ 230 extern void real_from_integer (REAL_VALUE_TYPE *, enum machine_mode, 231 unsigned HOST_WIDE_INT, HOST_WIDE_INT, int); 232 233 extern long real_to_target_fmt (long *, const REAL_VALUE_TYPE *, 234 const struct real_format *); 235 extern long real_to_target (long *, const REAL_VALUE_TYPE *, enum machine_mode); 236 237 extern void real_from_target_fmt (REAL_VALUE_TYPE *, const long *, 238 const struct real_format *); 239 extern void real_from_target (REAL_VALUE_TYPE *, const long *, 240 enum machine_mode); 241 242 extern void real_inf (REAL_VALUE_TYPE *); 243 244 extern bool real_nan (REAL_VALUE_TYPE *, const char *, int, enum machine_mode); 245 246 extern void real_maxval (REAL_VALUE_TYPE *, int, enum machine_mode); 247 248 extern void real_2expN (REAL_VALUE_TYPE *, int); 249 250 extern unsigned int real_hash (const REAL_VALUE_TYPE *); 251 252 253 /* Target formats defined in real.c. */ 254 extern const struct real_format ieee_single_format; 255 extern const struct real_format mips_single_format; 256 extern const struct real_format ieee_double_format; 257 extern const struct real_format mips_double_format; 258 extern const struct real_format ieee_extended_motorola_format; 259 extern const struct real_format ieee_extended_intel_96_format; 260 extern const struct real_format ieee_extended_intel_96_round_53_format; 261 extern const struct real_format ieee_extended_intel_128_format; 262 extern const struct real_format ibm_extended_format; 263 extern const struct real_format mips_extended_format; 264 extern const struct real_format ieee_quad_format; 265 extern const struct real_format mips_quad_format; 266 extern const struct real_format vax_f_format; 267 extern const struct real_format vax_d_format; 268 extern const struct real_format vax_g_format; 269 extern const struct real_format i370_single_format; 270 extern const struct real_format i370_double_format; 271 extern const struct real_format c4x_single_format; 272 extern const struct real_format c4x_extended_format; 273 extern const struct real_format real_internal_format; 274 extern const struct real_format decimal_single_format; 275 extern const struct real_format decimal_double_format; 276 extern const struct real_format decimal_quad_format; 277 278 279 /* ====================================================================== */ 280 /* Crap. */ 281 282 #define REAL_ARITHMETIC(value, code, d1, d2) \ 283 real_arithmetic (&(value), code, &(d1), &(d2)) 284 285 #define REAL_VALUES_IDENTICAL(x, y) real_identical (&(x), &(y)) 286 #define REAL_VALUES_EQUAL(x, y) real_compare (EQ_EXPR, &(x), &(y)) 287 #define REAL_VALUES_LESS(x, y) real_compare (LT_EXPR, &(x), &(y)) 288 289 /* Determine whether a floating-point value X is infinite. */ 290 #define REAL_VALUE_ISINF(x) real_isinf (&(x)) 291 292 /* Determine whether a floating-point value X is a NaN. */ 293 #define REAL_VALUE_ISNAN(x) real_isnan (&(x)) 294 295 /* Determine whether a floating-point value X is negative. */ 296 #define REAL_VALUE_NEGATIVE(x) real_isneg (&(x)) 297 298 /* Determine whether a floating-point value X is minus zero. */ 299 #define REAL_VALUE_MINUS_ZERO(x) real_isnegzero (&(x)) 300 301 /* IN is a REAL_VALUE_TYPE. OUT is an array of longs. */ 302 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) \ 303 real_to_target (OUT, &(IN), \ 304 mode_for_size (LONG_DOUBLE_TYPE_SIZE, MODE_FLOAT, 0)) 305 306 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \ 307 real_to_target (OUT, &(IN), mode_for_size (64, MODE_FLOAT, 0)) 308 309 /* IN is a REAL_VALUE_TYPE. OUT is a long. */ 310 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \ 311 ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_FLOAT, 0))) 312 313 #define REAL_VALUE_FROM_INT(r, lo, hi, mode) \ 314 real_from_integer (&(r), mode, lo, hi, 0) 315 316 #define REAL_VALUE_FROM_UNSIGNED_INT(r, lo, hi, mode) \ 317 real_from_integer (&(r), mode, lo, hi, 1) 318 319 /* Real values to IEEE 754R decimal floats. */ 320 321 /* IN is a REAL_VALUE_TYPE. OUT is an array of longs. */ 322 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \ 323 real_to_target (OUT, &(IN), mode_for_size (128, MODE_DECIMAL_FLOAT, 0)) 324 325 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \ 326 real_to_target (OUT, &(IN), mode_for_size (64, MODE_DECIMAL_FLOAT, 0)) 327 328 /* IN is a REAL_VALUE_TYPE. OUT is a long. */ 329 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \ 330 ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_DECIMAL_FLOAT, 0))) 331 332 extern REAL_VALUE_TYPE real_value_truncate (enum machine_mode, 333 REAL_VALUE_TYPE); 334 335 #define REAL_VALUE_TO_INT(plow, phigh, r) \ 336 real_to_integer2 (plow, phigh, &(r)) 337 338 extern REAL_VALUE_TYPE real_arithmetic2 (int, const REAL_VALUE_TYPE *, 339 const REAL_VALUE_TYPE *); 340 341 #define REAL_VALUE_NEGATE(X) \ 342 real_arithmetic2 (NEGATE_EXPR, &(X), NULL) 343 344 #define REAL_VALUE_ABS(X) \ 345 real_arithmetic2 (ABS_EXPR, &(X), NULL) 346 347 extern int significand_size (enum machine_mode); 348 349 extern REAL_VALUE_TYPE real_from_string2 (const char *, enum machine_mode); 350 351 #define REAL_VALUE_ATOF(s, m) \ 352 real_from_string2 (s, m) 353 354 #define CONST_DOUBLE_ATOF(s, m) \ 355 CONST_DOUBLE_FROM_REAL_VALUE (real_from_string2 (s, m), m) 356 357 #define REAL_VALUE_FIX(r) \ 358 real_to_integer (&(r)) 359 360 /* ??? Not quite right. */ 361 #define REAL_VALUE_UNSIGNED_FIX(r) \ 362 real_to_integer (&(r)) 363 364 /* ??? These were added for Paranoia support. */ 365 366 /* Return floor log2(R). */ 367 extern int real_exponent (const REAL_VALUE_TYPE *); 368 369 /* R = A * 2**EXP. */ 370 extern void real_ldexp (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *, int); 371 372 /* **** End of software floating point emulator interface macros **** */ 373 374 /* Constant real values 0, 1, 2, 3, 10, -1, -2, 0.5 and 1/3. */ 375 376 extern REAL_VALUE_TYPE dconst0; 377 extern REAL_VALUE_TYPE dconst1; 378 extern REAL_VALUE_TYPE dconst2; 379 extern REAL_VALUE_TYPE dconst3; 380 extern REAL_VALUE_TYPE dconst10; 381 extern REAL_VALUE_TYPE dconstm1; 382 extern REAL_VALUE_TYPE dconstm2; 383 extern REAL_VALUE_TYPE dconsthalf; 384 extern REAL_VALUE_TYPE dconstthird; 385 extern REAL_VALUE_TYPE dconstpi; 386 extern REAL_VALUE_TYPE dconste; 387 388 /* Function to return a real value (not a tree node) 389 from a given integer constant. */ 390 REAL_VALUE_TYPE real_value_from_int_cst (tree, tree); 391 392 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents. */ 393 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from) \ 394 ((to) = *CONST_DOUBLE_REAL_VALUE (from)) 395 396 /* Return a CONST_DOUBLE with value R and mode M. */ 397 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) \ 398 const_double_from_real_value (r, m) 399 extern rtx const_double_from_real_value (REAL_VALUE_TYPE, enum machine_mode); 400 401 /* Replace R by 1/R in the given machine mode, if the result is exact. */ 402 extern bool exact_real_inverse (enum machine_mode, REAL_VALUE_TYPE *); 403 404 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node. */ 405 extern tree build_real (tree, REAL_VALUE_TYPE); 406 407 /* Calculate R as the square root of X in the given machine mode. */ 408 extern bool real_sqrt (REAL_VALUE_TYPE *, enum machine_mode, 409 const REAL_VALUE_TYPE *); 410 411 /* Calculate R as X raised to the integer exponent N in mode MODE. */ 412 extern bool real_powi (REAL_VALUE_TYPE *, enum machine_mode, 413 const REAL_VALUE_TYPE *, HOST_WIDE_INT); 414 415 /* Standard round to integer value functions. */ 416 extern void real_trunc (REAL_VALUE_TYPE *, enum machine_mode, 417 const REAL_VALUE_TYPE *); 418 extern void real_floor (REAL_VALUE_TYPE *, enum machine_mode, 419 const REAL_VALUE_TYPE *); 420 extern void real_ceil (REAL_VALUE_TYPE *, enum machine_mode, 421 const REAL_VALUE_TYPE *); 422 extern void real_round (REAL_VALUE_TYPE *, enum machine_mode, 423 const REAL_VALUE_TYPE *); 424 425 /* Set the sign of R to the sign of X. */ 426 extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *); 427 428 #endif /* ! GCC_REAL_H */ 429