gcc/real.h

   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, 2009, 2010
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GCC.
   7
   8    GCC is free software; you can redistribute it and/or modify it under
   9    the terms of the GNU General Public License as published by the Free
  10    Software Foundation; either version 3, or (at your option) any later
  11    version.
  12
  13    GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16    for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GCC; see the file COPYING3.  If not see
  20    <http://www.gnu.org/licenses/>.  */
  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 GTY(()) real_value {
  44   /* Use the same underlying type for all bit-fields, so as to make
  45      sure they're packed together, otherwise REAL_VALUE_TYPE_SIZE will
  46      be miscomputed.  */
  47   unsigned int /* ENUM_BITFIELD (real_value_class) */ cl : 2;
  48   unsigned int decimal : 1;
  49   unsigned int sign : 1;
  50   unsigned int signalling : 1;
  51   unsigned int canonical : 1;
  52   unsigned int uexp : EXP_BITS;
  53   unsigned long sig[SIGSZ];
  54 };
  55
  56 #define REAL_EXP(REAL) \
  57   ((int)((REAL)->uexp ^ (unsigned int)(1 << (EXP_BITS - 1))) \
  58    - (1 << (EXP_BITS - 1)))
  59 #define SET_REAL_EXP(REAL, EXP) \
  60   ((REAL)->uexp = ((unsigned int)(EXP) & (unsigned int)((1 << EXP_BITS) - 1)))
  61
  62 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it
  63    needs to be a macro.  We do need to continue to have a structure tag
  64    so that other headers can forward declare it.  */
  65 #define REAL_VALUE_TYPE struct real_value
  66
  67 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in
  68    consecutive "w" slots.  Moreover, we've got to compute the number of "w"
  69    slots at preprocessor time, which means we can't use sizeof.  Guess.  */
  70
  71 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32)
  72 #define REAL_WIDTH \
  73   (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \
  74    + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */
  75
  76 /* Verify the guess.  */
  77 extern char test_real_width
  78   [sizeof(REAL_VALUE_TYPE) <= REAL_WIDTH*sizeof(HOST_WIDE_INT) ? 1 : -1];
  79
  80 /* Calculate the format for CONST_DOUBLE.  We need as many slots as
  81    are necessary to overlay a REAL_VALUE_TYPE on them.  This could be
  82    as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE).
  83
  84    A number of places assume that there are always at least two 'w'
  85    slots in a CONST_DOUBLE, so we provide them even if one would suffice.  */
  86
  87 #if REAL_WIDTH == 1
  88 # define CONST_DOUBLE_FORMAT     "ww"
  89 #else
  90 # if REAL_WIDTH == 2
  91 #  define CONST_DOUBLE_FORMAT    "ww"
  92 # else
  93 #  if REAL_WIDTH == 3
  94 #   define CONST_DOUBLE_FORMAT   "www"
  95 #  else
  96 #   if REAL_WIDTH == 4
  97 #    define CONST_DOUBLE_FORMAT  "wwww"
  98 #   else
  99 #    if REAL_WIDTH == 5
 100 #     define CONST_DOUBLE_FORMAT "wwwww"
 101 #    else
 102 #     if REAL_WIDTH == 6
 103 #      define CONST_DOUBLE_FORMAT "wwwwww"
 104 #     else
 105        #error "REAL_WIDTH > 6 not supported"
 106 #     endif
 107 #    endif
 108 #   endif
 109 #  endif
 110 # endif
 111 #endif
 112
 113
 114 /* Describes the properties of the specific target format in use.  */
 115 struct real_format
 116 {
 117   /* Move to and from the target bytes.  */
 118   void (*encode) (const struct real_format *, long *,
 119                   const REAL_VALUE_TYPE *);
 120   void (*decode) (const struct real_format *, REAL_VALUE_TYPE *,
 121                   const long *);
 122
 123   /* The radix of the exponent and digits of the significand.  */
 124   int b;
 125
 126   /* Size of the significand in digits of radix B.  */
 127   int p;
 128
 129   /* Size of the significant of a NaN, in digits of radix B.  */
 130   int pnan;
 131
 132   /* The minimum negative integer, x, such that b**(x-1) is normalized.  */
 133   int emin;
 134
 135   /* The maximum integer, x, such that b**(x-1) is representable.  */
 136   int emax;
 137
 138   /* The bit position of the sign bit, for determining whether a value
 139      is positive/negative, or -1 for a complex encoding.  */
 140   int signbit_ro;
 141
 142   /* The bit position of the sign bit, for changing the sign of a number,
 143      or -1 for a complex encoding.  */
 144   int signbit_rw;
 145
 146   /* Default rounding mode for operations on this format.  */
 147   bool round_towards_zero;
 148   bool has_sign_dependent_rounding;
 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   bool canonical_nan_lsbs_set;
 157 };
 158
 159
 160 /* The target format used for each floating point mode.
 161    Float modes are followed by decimal float modes, with entries for
 162    float modes indexed by (MODE - first float mode), and entries for
 163    decimal float modes indexed by (MODE - first decimal float mode) +
 164    the number of float modes.  */
 165 extern const struct real_format *
 166   real_format_for_mode[MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1
 167                        + MAX_MODE_DECIMAL_FLOAT - MIN_MODE_DECIMAL_FLOAT + 1];
 168
 169 #define REAL_MODE_FORMAT(MODE)                                          \
 170   (real_format_for_mode[DECIMAL_FLOAT_MODE_P (MODE)                     \
 171                         ? (((MODE) - MIN_MODE_DECIMAL_FLOAT)            \
 172                            + (MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1))     \
 173                         : ((MODE) - MIN_MODE_FLOAT)])
 174
 175 #define FLOAT_MODE_FORMAT(MODE) \
 176   (REAL_MODE_FORMAT (SCALAR_FLOAT_MODE_P (MODE)? (MODE) \
 177                                                : GET_MODE_INNER (MODE)))
 178
 179 /* The following macro determines whether the floating point format is
 180    composite, i.e. may contain non-consecutive mantissa bits, in which
 181    case compile-time FP overflow may not model run-time overflow.  */
 182 #define MODE_COMPOSITE_P(MODE) \
 183   (FLOAT_MODE_P (MODE) \
 184    && FLOAT_MODE_FORMAT (MODE)->pnan < FLOAT_MODE_FORMAT (MODE)->p)
 185
 186 /* Accessor macros for format properties.  */
 187 #define MODE_HAS_NANS(MODE) \
 188   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_nans)
 189 #define MODE_HAS_INFINITIES(MODE) \
 190   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_inf)
 191 #define MODE_HAS_SIGNED_ZEROS(MODE) \
 192   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_signed_zero)
 193 #define MODE_HAS_SIGN_DEPENDENT_ROUNDING(MODE) \
 194   (FLOAT_MODE_P (MODE) \
 195    && FLOAT_MODE_FORMAT (MODE)->has_sign_dependent_rounding)
 196
 197 /* True if the given mode has a NaN representation and the treatment of
 198    NaN operands is important.  Certain optimizations, such as folding
 199    x * 0 into 0, are not correct for NaN operands, and are normally
 200    disabled for modes with NaNs.  The user can ask for them to be
 201    done anyway using the -funsafe-math-optimizations switch.  */
 202 #define HONOR_NANS(MODE) \
 203   (MODE_HAS_NANS (MODE) && !flag_finite_math_only)
 204
 205 /* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs).  */
 206 #define HONOR_SNANS(MODE) (flag_signaling_nans && HONOR_NANS (MODE))
 207
 208 /* As for HONOR_NANS, but true if the mode can represent infinity and
 209    the treatment of infinite values is important.  */
 210 #define HONOR_INFINITIES(MODE) \
 211   (MODE_HAS_INFINITIES (MODE) && !flag_finite_math_only)
 212
 213 /* Like HONOR_NANS, but true if the given mode distinguishes between
 214    positive and negative zero, and the sign of zero is important.  */
 215 #define HONOR_SIGNED_ZEROS(MODE) \
 216   (MODE_HAS_SIGNED_ZEROS (MODE) && flag_signed_zeros)
 217
 218 /* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
 219    and the rounding mode is important.  */
 220 #define HONOR_SIGN_DEPENDENT_ROUNDING(MODE) \
 221   (MODE_HAS_SIGN_DEPENDENT_ROUNDING (MODE) && flag_rounding_math)
 222
 223 /* Declare functions in real.c.  */
 224
 225 /* Binary or unary arithmetic on tree_code.  */
 226 extern bool real_arithmetic (REAL_VALUE_TYPE *, int, const REAL_VALUE_TYPE *,
 227                              const REAL_VALUE_TYPE *);
 228
 229 /* Compare reals by tree_code.  */
 230 extern bool real_compare (int, const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 231
 232 /* Determine whether a floating-point value X is infinite.  */
 233 extern bool real_isinf (const REAL_VALUE_TYPE *);
 234
 235 /* Determine whether a floating-point value X is a NaN.  */
 236 extern bool real_isnan (const REAL_VALUE_TYPE *);
 237
 238 /* Determine whether a floating-point value X is finite.  */
 239 extern bool real_isfinite (const REAL_VALUE_TYPE *);
 240
 241 /* Determine whether a floating-point value X is negative.  */
 242 extern bool real_isneg (const REAL_VALUE_TYPE *);
 243
 244 /* Determine whether a floating-point value X is minus zero.  */
 245 extern bool real_isnegzero (const REAL_VALUE_TYPE *);
 246
 247 /* Compare two floating-point objects for bitwise identity.  */
 248 extern bool real_identical (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 249
 250 /* Extend or truncate to a new mode.  */
 251 extern void real_convert (REAL_VALUE_TYPE *, enum machine_mode,
 252                           const REAL_VALUE_TYPE *);
 253
 254 /* Return true if truncating to NEW is exact.  */
 255 extern bool exact_real_truncate (enum machine_mode, const REAL_VALUE_TYPE *);
 256
 257 /* Render R as a decimal floating point constant.  */
 258 extern void real_to_decimal (char *, const REAL_VALUE_TYPE *, size_t,
 259                              size_t, int);
 260
 261 /* Render R as a decimal floating point constant, rounded so as to be
 262    parsed back to the same value when interpreted in mode MODE.  */
 263 extern void real_to_decimal_for_mode (char *, const REAL_VALUE_TYPE *, size_t,
 264                                       size_t, int, enum machine_mode);
 265
 266 /* Render R as a hexadecimal floating point constant.  */
 267 extern void real_to_hexadecimal (char *, const REAL_VALUE_TYPE *,
 268                                  size_t, size_t, int);
 269
 270 /* Render R as an integer.  */
 271 extern HOST_WIDE_INT real_to_integer (const REAL_VALUE_TYPE *);
 272 extern void real_to_integer2 (HOST_WIDE_INT *, HOST_WIDE_INT *,
 273                               const REAL_VALUE_TYPE *);
 274
 275 /* Initialize R from a decimal or hexadecimal string.  Return -1 if
 276    the value underflows, +1 if overflows, and 0 otherwise.  */
 277 extern int real_from_string (REAL_VALUE_TYPE *, const char *);
 278 /* Wrapper to allow different internal representation for decimal floats. */
 279 extern void real_from_string3 (REAL_VALUE_TYPE *, const char *, enum machine_mode);
 280
 281 /* Initialize R from an integer pair HIGH/LOW.  */
 282 extern void real_from_integer (REAL_VALUE_TYPE *, enum machine_mode,
 283                                unsigned HOST_WIDE_INT, HOST_WIDE_INT, int);
 284
 285 extern long real_to_target_fmt (long *, const REAL_VALUE_TYPE *,
 286                                 const struct real_format *);
 287 extern long real_to_target (long *, const REAL_VALUE_TYPE *, enum machine_mode);
 288
 289 extern void real_from_target_fmt (REAL_VALUE_TYPE *, const long *,
 290                                   const struct real_format *);
 291 extern void real_from_target (REAL_VALUE_TYPE *, const long *,
 292                               enum machine_mode);
 293
 294 extern void real_inf (REAL_VALUE_TYPE *);
 295
 296 extern bool real_nan (REAL_VALUE_TYPE *, const char *, int, enum machine_mode);
 297
 298 extern void real_maxval (REAL_VALUE_TYPE *, int, enum machine_mode);
 299
 300 extern void real_2expN (REAL_VALUE_TYPE *, int, enum machine_mode);
 301
 302 extern unsigned int real_hash (const REAL_VALUE_TYPE *);
 303
 304
 305 /* Target formats defined in real.c.  */
 306 extern const struct real_format ieee_single_format;
 307 extern const struct real_format mips_single_format;
 308 extern const struct real_format motorola_single_format;
 309 extern const struct real_format spu_single_format;
 310 extern const struct real_format ieee_double_format;
 311 extern const struct real_format mips_double_format;
 312 extern const struct real_format motorola_double_format;
 313 extern const struct real_format ieee_extended_motorola_format;
 314 extern const struct real_format ieee_extended_intel_96_format;
 315 extern const struct real_format ieee_extended_intel_96_round_53_format;
 316 extern const struct real_format ieee_extended_intel_128_format;
 317 extern const struct real_format ibm_extended_format;
 318 extern const struct real_format mips_extended_format;
 319 extern const struct real_format ieee_quad_format;
 320 extern const struct real_format mips_quad_format;
 321 extern const struct real_format vax_f_format;
 322 extern const struct real_format vax_d_format;
 323 extern const struct real_format vax_g_format;
 324 extern const struct real_format real_internal_format;
 325 extern const struct real_format decimal_single_format;
 326 extern const struct real_format decimal_double_format;
 327 extern const struct real_format decimal_quad_format;
 328 extern const struct real_format ieee_half_format;
 329 extern const struct real_format arm_half_format;
 330
 331
 332 /* ====================================================================== */
 333 /* Crap.  */
 334
 335 #define REAL_ARITHMETIC(value, code, d1, d2) \
 336   real_arithmetic (&(value), code, &(d1), &(d2))
 337
 338 #define REAL_VALUES_IDENTICAL(x, y)     real_identical (&(x), &(y))
 339 #define REAL_VALUES_EQUAL(x, y)         real_compare (EQ_EXPR, &(x), &(y))
 340 #define REAL_VALUES_LESS(x, y)          real_compare (LT_EXPR, &(x), &(y))
 341
 342 /* Determine whether a floating-point value X is infinite.  */
 343 #define REAL_VALUE_ISINF(x)             real_isinf (&(x))
 344
 345 /* Determine whether a floating-point value X is a NaN.  */
 346 #define REAL_VALUE_ISNAN(x)             real_isnan (&(x))
 347
 348 /* Determine whether a floating-point value X is negative.  */
 349 #define REAL_VALUE_NEGATIVE(x)          real_isneg (&(x))
 350
 351 /* Determine whether a floating-point value X is minus zero.  */
 352 #define REAL_VALUE_MINUS_ZERO(x)        real_isnegzero (&(x))
 353
 354 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 355 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)                       \
 356   real_to_target (OUT, &(IN),                                           \
 357                   mode_for_size (LONG_DOUBLE_TYPE_SIZE, MODE_FLOAT, 0))
 358
 359 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \
 360   real_to_target (OUT, &(IN), mode_for_size (64, MODE_FLOAT, 0))
 361
 362 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 363 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \
 364   ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_FLOAT, 0)))
 365
 366 #define REAL_VALUE_FROM_INT(r, lo, hi, mode) \
 367   real_from_integer (&(r), mode, lo, hi, 0)
 368
 369 #define REAL_VALUE_FROM_UNSIGNED_INT(r, lo, hi, mode) \
 370   real_from_integer (&(r), mode, lo, hi, 1)
 371
 372 /* Real values to IEEE 754 decimal floats.  */
 373
 374 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 375 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \
 376   real_to_target (OUT, &(IN), mode_for_size (128, MODE_DECIMAL_FLOAT, 0))
 377
 378 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \
 379   real_to_target (OUT, &(IN), mode_for_size (64, MODE_DECIMAL_FLOAT, 0))
 380
 381 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 382 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \
 383   ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_DECIMAL_FLOAT, 0)))
 384
 385 extern REAL_VALUE_TYPE real_value_truncate (enum machine_mode,
 386                                             REAL_VALUE_TYPE);
 387
 388 #define REAL_VALUE_TO_INT(plow, phigh, r) \
 389   real_to_integer2 (plow, phigh, &(r))
 390
 391 extern REAL_VALUE_TYPE real_value_negate (const REAL_VALUE_TYPE *);
 392 extern REAL_VALUE_TYPE real_value_abs (const REAL_VALUE_TYPE *);
 393
 394 extern int significand_size (enum machine_mode);
 395
 396 extern REAL_VALUE_TYPE real_from_string2 (const char *, enum machine_mode);
 397
 398 #define REAL_VALUE_ATOF(s, m) \
 399   real_from_string2 (s, m)
 400
 401 #define CONST_DOUBLE_ATOF(s, m) \
 402   CONST_DOUBLE_FROM_REAL_VALUE (real_from_string2 (s, m), m)
 403
 404 #define REAL_VALUE_FIX(r) \
 405   real_to_integer (&(r))
 406
 407 /* ??? Not quite right.  */
 408 #define REAL_VALUE_UNSIGNED_FIX(r) \
 409   real_to_integer (&(r))
 410
 411 /* ??? These were added for Paranoia support.  */
 412
 413 /* Return floor log2(R).  */
 414 extern int real_exponent (const REAL_VALUE_TYPE *);
 415
 416 /* R = A * 2**EXP.  */
 417 extern void real_ldexp (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *, int);
 418
 419 /* **** End of software floating point emulator interface macros **** */
 420 \f
 421 /* Constant real values 0, 1, 2, -1 and 0.5.  */
 422
 423 extern REAL_VALUE_TYPE dconst0;
 424 extern REAL_VALUE_TYPE dconst1;
 425 extern REAL_VALUE_TYPE dconst2;
 426 extern REAL_VALUE_TYPE dconstm1;
 427 extern REAL_VALUE_TYPE dconsthalf;
 428
 429 #define dconst_e()  (*dconst_e_ptr ())
 430 #define dconst_third()  (*dconst_third_ptr ())
 431 #define dconst_sqrt2()  (*dconst_sqrt2_ptr ())
 432
 433 /* Function to return the real value special constant 'e'.  */
 434 extern const REAL_VALUE_TYPE * dconst_e_ptr (void);
 435
 436 /* Returns the special REAL_VALUE_TYPE corresponding to 1/3.  */
 437 extern const REAL_VALUE_TYPE * dconst_third_ptr (void);
 438
 439 /* Returns the special REAL_VALUE_TYPE corresponding to sqrt(2).  */
 440 extern const REAL_VALUE_TYPE * dconst_sqrt2_ptr (void);
 441
 442 /* Function to return a real value (not a tree node)
 443    from a given integer constant.  */
 444 REAL_VALUE_TYPE real_value_from_int_cst (const_tree, const_tree);
 445
 446 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents.  */
 447 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from) \
 448   ((to) = *CONST_DOUBLE_REAL_VALUE (from))
 449
 450 /* Return a CONST_DOUBLE with value R and mode M.  */
 451 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) \
 452   const_double_from_real_value (r, m)
 453 extern rtx const_double_from_real_value (REAL_VALUE_TYPE, enum machine_mode);
 454
 455 /* Replace R by 1/R in the given machine mode, if the result is exact.  */
 456 extern bool exact_real_inverse (enum machine_mode, REAL_VALUE_TYPE *);
 457
 458 /* Return true if arithmetic on values in IMODE that were promoted
 459    from values in TMODE is equivalent to direct arithmetic on values
 460    in TMODE.  */
 461 bool real_can_shorten_arithmetic (enum machine_mode, enum machine_mode);
 462
 463 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node.  */
 464 extern tree build_real (tree, REAL_VALUE_TYPE);
 465
 466 /* Calculate R as the square root of X in the given machine mode.  */
 467 extern bool real_sqrt (REAL_VALUE_TYPE *, enum machine_mode,
 468                        const REAL_VALUE_TYPE *);
 469
 470 /* Calculate R as X raised to the integer exponent N in mode MODE.  */
 471 extern bool real_powi (REAL_VALUE_TYPE *, enum machine_mode,
 472                        const REAL_VALUE_TYPE *, HOST_WIDE_INT);
 473
 474 /* Standard round to integer value functions.  */
 475 extern void real_trunc (REAL_VALUE_TYPE *, enum machine_mode,
 476                         const REAL_VALUE_TYPE *);
 477 extern void real_floor (REAL_VALUE_TYPE *, enum machine_mode,
 478                         const REAL_VALUE_TYPE *);
 479 extern void real_ceil (REAL_VALUE_TYPE *, enum machine_mode,
 480                        const REAL_VALUE_TYPE *);
 481 extern void real_round (REAL_VALUE_TYPE *, enum machine_mode,
 482                         const REAL_VALUE_TYPE *);
 483
 484 /* Set the sign of R to the sign of X.  */
 485 extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 486
 487 /* Check whether the real constant value given is an integer.  */
 488 extern bool real_isinteger (const REAL_VALUE_TYPE *c, enum machine_mode mode);
 489
 490 /* Write into BUF the maximum representable finite floating-point
 491    number, (1 - b**-p) * b**emax for a given FP format FMT as a hex
 492    float string.  BUF must be large enough to contain the result.  */
 493 extern void get_max_float (const struct real_format *, char *, size_t);
 494 #endif /* ! GCC_REAL_H */