gcc/real.h

   1 /* Definitions of floating-point access for GNU compiler.
   2    Copyright (C) 1989-2015 Free Software Foundation, Inc.
   3
   4    This file is part of GCC.
   5
   6    GCC is free software; you can redistribute it and/or modify it under
   7    the terms of the GNU General Public License as published by the Free
   8    Software Foundation; either version 3, or (at your option) any later
   9    version.
  10
  11    GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14    for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GCC; see the file COPYING3.  If not see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_REAL_H
  21 #define GCC_REAL_H
  22
  23 /* An expanded form of the represented number.  */
  24
  25 /* Enumerate the special cases of numbers that we encounter.  */
  26 enum real_value_class {
  27   rvc_zero,
  28   rvc_normal,
  29   rvc_inf,
  30   rvc_nan
  31 };
  32
  33 #define SIGNIFICAND_BITS        (128 + HOST_BITS_PER_LONG)
  34 #define EXP_BITS                (32 - 6)
  35 #define MAX_EXP                 ((1 << (EXP_BITS - 1)) - 1)
  36 #define SIGSZ                   (SIGNIFICAND_BITS / HOST_BITS_PER_LONG)
  37 #define SIG_MSB                 ((unsigned long)1 << (HOST_BITS_PER_LONG - 1))
  38
  39 struct GTY(()) real_value {
  40   /* Use the same underlying type for all bit-fields, so as to make
  41      sure they're packed together, otherwise REAL_VALUE_TYPE_SIZE will
  42      be miscomputed.  */
  43   unsigned int /* ENUM_BITFIELD (real_value_class) */ cl : 2;
  44   unsigned int decimal : 1;
  45   unsigned int sign : 1;
  46   unsigned int signalling : 1;
  47   unsigned int canonical : 1;
  48   unsigned int uexp : EXP_BITS;
  49   unsigned long sig[SIGSZ];
  50 };
  51
  52 #define REAL_EXP(REAL) \
  53   ((int)((REAL)->uexp ^ (unsigned int)(1 << (EXP_BITS - 1))) \
  54    - (1 << (EXP_BITS - 1)))
  55 #define SET_REAL_EXP(REAL, EXP) \
  56   ((REAL)->uexp = ((unsigned int)(EXP) & (unsigned int)((1 << EXP_BITS) - 1)))
  57
  58 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it
  59    needs to be a macro.  We do need to continue to have a structure tag
  60    so that other headers can forward declare it.  */
  61 #define REAL_VALUE_TYPE struct real_value
  62
  63 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in
  64    consecutive "w" slots.  Moreover, we've got to compute the number of "w"
  65    slots at preprocessor time, which means we can't use sizeof.  Guess.  */
  66
  67 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32)
  68 #define REAL_WIDTH \
  69   (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \
  70    + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */
  71
  72 /* Verify the guess.  */
  73 extern char test_real_width
  74   [sizeof (REAL_VALUE_TYPE) <= REAL_WIDTH * sizeof (HOST_WIDE_INT) ? 1 : -1];
  75
  76 /* Calculate the format for CONST_DOUBLE.  We need as many slots as
  77    are necessary to overlay a REAL_VALUE_TYPE on them.  This could be
  78    as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE).
  79
  80    A number of places assume that there are always at least two 'w'
  81    slots in a CONST_DOUBLE, so we provide them even if one would suffice.  */
  82
  83 #if REAL_WIDTH == 1
  84 # define CONST_DOUBLE_FORMAT     "ww"
  85 #else
  86 # if REAL_WIDTH == 2
  87 #  define CONST_DOUBLE_FORMAT    "ww"
  88 # else
  89 #  if REAL_WIDTH == 3
  90 #   define CONST_DOUBLE_FORMAT   "www"
  91 #  else
  92 #   if REAL_WIDTH == 4
  93 #    define CONST_DOUBLE_FORMAT  "wwww"
  94 #   else
  95 #    if REAL_WIDTH == 5
  96 #     define CONST_DOUBLE_FORMAT "wwwww"
  97 #    else
  98 #     if REAL_WIDTH == 6
  99 #      define CONST_DOUBLE_FORMAT "wwwwww"
 100 #     else
 101        #error "REAL_WIDTH > 6 not supported"
 102 #     endif
 103 #    endif
 104 #   endif
 105 #  endif
 106 # endif
 107 #endif
 108
 109
 110 /* Describes the properties of the specific target format in use.  */
 111 struct real_format
 112 {
 113   /* Move to and from the target bytes.  */
 114   void (*encode) (const struct real_format *, long *,
 115                   const REAL_VALUE_TYPE *);
 116   void (*decode) (const struct real_format *, REAL_VALUE_TYPE *,
 117                   const long *);
 118
 119   /* The radix of the exponent and digits of the significand.  */
 120   int b;
 121
 122   /* Size of the significand in digits of radix B.  */
 123   int p;
 124
 125   /* Size of the significant of a NaN, in digits of radix B.  */
 126   int pnan;
 127
 128   /* The minimum negative integer, x, such that b**(x-1) is normalized.  */
 129   int emin;
 130
 131   /* The maximum integer, x, such that b**(x-1) is representable.  */
 132   int emax;
 133
 134   /* The bit position of the sign bit, for determining whether a value
 135      is positive/negative, or -1 for a complex encoding.  */
 136   int signbit_ro;
 137
 138   /* The bit position of the sign bit, for changing the sign of a number,
 139      or -1 for a complex encoding.  */
 140   int signbit_rw;
 141
 142   /* Default rounding mode for operations on this format.  */
 143   bool round_towards_zero;
 144   bool has_sign_dependent_rounding;
 145
 146   /* Properties of the format.  */
 147   bool has_nans;
 148   bool has_inf;
 149   bool has_denorm;
 150   bool has_signed_zero;
 151   bool qnan_msb_set;
 152   bool canonical_nan_lsbs_set;
 153   const char *name;
 154 };
 155
 156
 157 /* The target format used for each floating point mode.
 158    Float modes are followed by decimal float modes, with entries for
 159    float modes indexed by (MODE - first float mode), and entries for
 160    decimal float modes indexed by (MODE - first decimal float mode) +
 161    the number of float modes.  */
 162 extern const struct real_format *
 163   real_format_for_mode[MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1
 164                        + MAX_MODE_DECIMAL_FLOAT - MIN_MODE_DECIMAL_FLOAT + 1];
 165
 166 #define REAL_MODE_FORMAT(MODE)                                          \
 167   (real_format_for_mode[DECIMAL_FLOAT_MODE_P (MODE)                     \
 168                         ? (((MODE) - MIN_MODE_DECIMAL_FLOAT)            \
 169                            + (MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1))     \
 170                         : GET_MODE_CLASS (MODE) == MODE_FLOAT           \
 171                         ? ((MODE) - MIN_MODE_FLOAT)                     \
 172                         : (gcc_unreachable (), 0)])
 173
 174 #define FLOAT_MODE_FORMAT(MODE) \
 175   (REAL_MODE_FORMAT (SCALAR_FLOAT_MODE_P (MODE)? (MODE) \
 176                                                : GET_MODE_INNER (MODE)))
 177
 178 /* The following macro determines whether the floating point format is
 179    composite, i.e. may contain non-consecutive mantissa bits, in which
 180    case compile-time FP overflow may not model run-time overflow.  */
 181 #define MODE_COMPOSITE_P(MODE) \
 182   (FLOAT_MODE_P (MODE) \
 183    && FLOAT_MODE_FORMAT (MODE)->pnan < FLOAT_MODE_FORMAT (MODE)->p)
 184
 185 /* Accessor macros for format properties.  */
 186 #define MODE_HAS_NANS(MODE) \
 187   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_nans)
 188 #define MODE_HAS_INFINITIES(MODE) \
 189   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_inf)
 190 #define MODE_HAS_SIGNED_ZEROS(MODE) \
 191   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_signed_zero)
 192 #define MODE_HAS_SIGN_DEPENDENT_ROUNDING(MODE) \
 193   (FLOAT_MODE_P (MODE) \
 194    && FLOAT_MODE_FORMAT (MODE)->has_sign_dependent_rounding)
 195
 196 /* This class allows functions in this file to accept a floating-point
 197    format as either a mode or an explicit real_format pointer.  In the
 198    former case the mode must be VOIDmode (which means "no particular
 199    format") or must satisfy SCALAR_FLOAT_MODE_P.  */
 200 class format_helper
 201 {
 202 public:
 203   format_helper (const real_format *format) : m_format (format) {}
 204   format_helper (machine_mode m);
 205   const real_format *operator-> () const { return m_format; }
 206   operator const real_format *() const { return m_format; }
 207
 208   bool decimal_p () const { return m_format && m_format->b == 10; }
 209
 210 private:
 211   const real_format *m_format;
 212 };
 213
 214 inline format_helper::format_helper (machine_mode m)
 215   : m_format (m == VOIDmode ? 0 : REAL_MODE_FORMAT (m))
 216 {}
 217
 218 /* Declare functions in real.c.  */
 219
 220 /* True if the given mode has a NaN representation and the treatment of
 221    NaN operands is important.  Certain optimizations, such as folding
 222    x * 0 into 0, are not correct for NaN operands, and are normally
 223    disabled for modes with NaNs.  The user can ask for them to be
 224    done anyway using the -funsafe-math-optimizations switch.  */
 225 extern bool HONOR_NANS (machine_mode);
 226 extern bool HONOR_NANS (const_tree);
 227 extern bool HONOR_NANS (const_rtx);
 228
 229 /* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs).  */
 230 extern bool HONOR_SNANS (machine_mode);
 231 extern bool HONOR_SNANS (const_tree);
 232 extern bool HONOR_SNANS (const_rtx);
 233
 234 /* As for HONOR_NANS, but true if the mode can represent infinity and
 235    the treatment of infinite values is important.  */
 236 extern bool HONOR_INFINITIES (machine_mode);
 237 extern bool HONOR_INFINITIES (const_tree);
 238 extern bool HONOR_INFINITIES (const_rtx);
 239
 240 /* Like HONOR_NANS, but true if the given mode distinguishes between
 241    positive and negative zero, and the sign of zero is important.  */
 242 extern bool HONOR_SIGNED_ZEROS (machine_mode);
 243 extern bool HONOR_SIGNED_ZEROS (const_tree);
 244 extern bool HONOR_SIGNED_ZEROS (const_rtx);
 245
 246 /* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
 247    and the rounding mode is important.  */
 248 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (machine_mode);
 249 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_tree);
 250 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_rtx);
 251
 252 /* Binary or unary arithmetic on tree_code.  */
 253 extern bool real_arithmetic (REAL_VALUE_TYPE *, int, const REAL_VALUE_TYPE *,
 254                              const REAL_VALUE_TYPE *);
 255
 256 /* Compare reals by tree_code.  */
 257 extern bool real_compare (int, const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 258
 259 /* Determine whether a floating-point value X is infinite.  */
 260 extern bool real_isinf (const REAL_VALUE_TYPE *);
 261
 262 /* Determine whether a floating-point value X is a NaN.  */
 263 extern bool real_isnan (const REAL_VALUE_TYPE *);
 264
 265 /* Determine whether a floating-point value X is finite.  */
 266 extern bool real_isfinite (const REAL_VALUE_TYPE *);
 267
 268 /* Determine whether a floating-point value X is negative.  */
 269 extern bool real_isneg (const REAL_VALUE_TYPE *);
 270
 271 /* Determine whether a floating-point value X is minus zero.  */
 272 extern bool real_isnegzero (const REAL_VALUE_TYPE *);
 273
 274 /* Test relationships between reals.  */
 275 extern bool real_identical (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 276 extern bool real_equal (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 277 extern bool real_less (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 278
 279 /* Extend or truncate to a new format.  */
 280 extern void real_convert (REAL_VALUE_TYPE *, format_helper,
 281                           const REAL_VALUE_TYPE *);
 282
 283 /* Return true if truncating to NEW is exact.  */
 284 extern bool exact_real_truncate (format_helper, const REAL_VALUE_TYPE *);
 285
 286 /* Render R as a decimal floating point constant.  */
 287 extern void real_to_decimal (char *, const REAL_VALUE_TYPE *, size_t,
 288                              size_t, int);
 289
 290 /* Render R as a decimal floating point constant, rounded so as to be
 291    parsed back to the same value when interpreted in mode MODE.  */
 292 extern void real_to_decimal_for_mode (char *, const REAL_VALUE_TYPE *, size_t,
 293                                       size_t, int, machine_mode);
 294
 295 /* Render R as a hexadecimal floating point constant.  */
 296 extern void real_to_hexadecimal (char *, const REAL_VALUE_TYPE *,
 297                                  size_t, size_t, int);
 298
 299 /* Render R as an integer.  */
 300 extern HOST_WIDE_INT real_to_integer (const REAL_VALUE_TYPE *);
 301
 302 /* Initialize R from a decimal or hexadecimal string.  Return -1 if
 303    the value underflows, +1 if overflows, and 0 otherwise.  */
 304 extern int real_from_string (REAL_VALUE_TYPE *, const char *);
 305 /* Wrapper to allow different internal representation for decimal floats. */
 306 extern void real_from_string3 (REAL_VALUE_TYPE *, const char *, format_helper);
 307
 308 extern long real_to_target (long *, const REAL_VALUE_TYPE *, format_helper);
 309
 310 extern void real_from_target (REAL_VALUE_TYPE *, const long *,
 311                               format_helper);
 312
 313 extern void real_inf (REAL_VALUE_TYPE *);
 314
 315 extern bool real_nan (REAL_VALUE_TYPE *, const char *, int, format_helper);
 316
 317 extern void real_maxval (REAL_VALUE_TYPE *, int, machine_mode);
 318
 319 extern void real_2expN (REAL_VALUE_TYPE *, int, format_helper);
 320
 321 extern unsigned int real_hash (const REAL_VALUE_TYPE *);
 322
 323
 324 /* Target formats defined in real.c.  */
 325 extern const struct real_format ieee_single_format;
 326 extern const struct real_format mips_single_format;
 327 extern const struct real_format motorola_single_format;
 328 extern const struct real_format spu_single_format;
 329 extern const struct real_format ieee_double_format;
 330 extern const struct real_format mips_double_format;
 331 extern const struct real_format motorola_double_format;
 332 extern const struct real_format ieee_extended_motorola_format;
 333 extern const struct real_format ieee_extended_intel_96_format;
 334 extern const struct real_format ieee_extended_intel_96_round_53_format;
 335 extern const struct real_format ieee_extended_intel_128_format;
 336 extern const struct real_format ibm_extended_format;
 337 extern const struct real_format mips_extended_format;
 338 extern const struct real_format ieee_quad_format;
 339 extern const struct real_format mips_quad_format;
 340 extern const struct real_format vax_f_format;
 341 extern const struct real_format vax_d_format;
 342 extern const struct real_format vax_g_format;
 343 extern const struct real_format real_internal_format;
 344 extern const struct real_format decimal_single_format;
 345 extern const struct real_format decimal_double_format;
 346 extern const struct real_format decimal_quad_format;
 347 extern const struct real_format ieee_half_format;
 348 extern const struct real_format arm_half_format;
 349
 350
 351 /* ====================================================================== */
 352 /* Crap.  */
 353
 354 /* Determine whether a floating-point value X is infinite.  */
 355 #define REAL_VALUE_ISINF(x)             real_isinf (&(x))
 356
 357 /* Determine whether a floating-point value X is a NaN.  */
 358 #define REAL_VALUE_ISNAN(x)             real_isnan (&(x))
 359
 360 /* Determine whether a floating-point value X is negative.  */
 361 #define REAL_VALUE_NEGATIVE(x)          real_isneg (&(x))
 362
 363 /* Determine whether a floating-point value X is minus zero.  */
 364 #define REAL_VALUE_MINUS_ZERO(x)        real_isnegzero (&(x))
 365
 366 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 367 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)                       \
 368   real_to_target (OUT, &(IN),                                           \
 369                   mode_for_size (LONG_DOUBLE_TYPE_SIZE, MODE_FLOAT, 0))
 370
 371 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \
 372   real_to_target (OUT, &(IN), mode_for_size (64, MODE_FLOAT, 0))
 373
 374 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 375 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \
 376   ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_FLOAT, 0)))
 377
 378 /* Real values to IEEE 754 decimal floats.  */
 379
 380 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 381 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \
 382   real_to_target (OUT, &(IN), mode_for_size (128, MODE_DECIMAL_FLOAT, 0))
 383
 384 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \
 385   real_to_target (OUT, &(IN), mode_for_size (64, MODE_DECIMAL_FLOAT, 0))
 386
 387 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 388 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \
 389   ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_DECIMAL_FLOAT, 0)))
 390
 391 extern REAL_VALUE_TYPE real_value_truncate (format_helper, REAL_VALUE_TYPE);
 392
 393 extern REAL_VALUE_TYPE real_value_negate (const REAL_VALUE_TYPE *);
 394 extern REAL_VALUE_TYPE real_value_abs (const REAL_VALUE_TYPE *);
 395
 396 extern int significand_size (format_helper);
 397
 398 extern REAL_VALUE_TYPE real_from_string2 (const char *, format_helper);
 399
 400 #define REAL_VALUE_ATOF(s, m) \
 401   real_from_string2 (s, m)
 402
 403 #define CONST_DOUBLE_ATOF(s, m) \
 404   const_double_from_real_value (real_from_string2 (s, m), m)
 405
 406 #define REAL_VALUE_FIX(r) \
 407   real_to_integer (&(r))
 408
 409 /* ??? Not quite right.  */
 410 #define REAL_VALUE_UNSIGNED_FIX(r) \
 411   real_to_integer (&(r))
 412
 413 /* ??? These were added for Paranoia support.  */
 414
 415 /* Return floor log2(R).  */
 416 extern int real_exponent (const REAL_VALUE_TYPE *);
 417
 418 /* R = A * 2**EXP.  */
 419 extern void real_ldexp (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *, int);
 420
 421 /* **** End of software floating point emulator interface macros **** */
 422 \f
 423 /* Constant real values 0, 1, 2, -1 and 0.5.  */
 424
 425 extern REAL_VALUE_TYPE dconst0;
 426 extern REAL_VALUE_TYPE dconst1;
 427 extern REAL_VALUE_TYPE dconst2;
 428 extern REAL_VALUE_TYPE dconstm1;
 429 extern REAL_VALUE_TYPE dconsthalf;
 430
 431 #define dconst_e() (*dconst_e_ptr ())
 432 #define dconst_third() (*dconst_third_ptr ())
 433 #define dconst_quarter() (*dconst_quarter_ptr ())
 434 #define dconst_sixth() (*dconst_sixth_ptr ())
 435 #define dconst_ninth() (*dconst_ninth_ptr ())
 436 #define dconst_sqrt2() (*dconst_sqrt2_ptr ())
 437
 438 /* Function to return the real value special constant 'e'.  */
 439 extern const REAL_VALUE_TYPE * dconst_e_ptr (void);
 440
 441 /* Returns a cached REAL_VALUE_TYPE corresponding to 1/n, for various n.  */
 442 extern const REAL_VALUE_TYPE *dconst_third_ptr (void);
 443 extern const REAL_VALUE_TYPE *dconst_quarter_ptr (void);
 444 extern const REAL_VALUE_TYPE *dconst_sixth_ptr (void);
 445 extern const REAL_VALUE_TYPE *dconst_ninth_ptr (void);
 446
 447 /* Returns the special REAL_VALUE_TYPE corresponding to sqrt(2).  */
 448 extern const REAL_VALUE_TYPE * dconst_sqrt2_ptr (void);
 449
 450 /* Function to return a real value (not a tree node)
 451    from a given integer constant.  */
 452 REAL_VALUE_TYPE real_value_from_int_cst (const_tree, const_tree);
 453
 454 /* Return a CONST_DOUBLE with value R and mode M.  */
 455 extern rtx const_double_from_real_value (REAL_VALUE_TYPE, machine_mode);
 456
 457 /* Replace R by 1/R in the given format, if the result is exact.  */
 458 extern bool exact_real_inverse (format_helper, REAL_VALUE_TYPE *);
 459
 460 /* Return true if arithmetic on values in IMODE that were promoted
 461    from values in TMODE is equivalent to direct arithmetic on values
 462    in TMODE.  */
 463 bool real_can_shorten_arithmetic (machine_mode, machine_mode);
 464
 465 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node.  */
 466 extern tree build_real (tree, REAL_VALUE_TYPE);
 467
 468 /* Likewise, but first truncate the value to the type.  */
 469 extern tree build_real_truncate (tree, REAL_VALUE_TYPE);
 470
 471 /* Calculate R as X raised to the integer exponent N in format FMT.  */
 472 extern bool real_powi (REAL_VALUE_TYPE *, format_helper,
 473                        const REAL_VALUE_TYPE *, HOST_WIDE_INT);
 474
 475 /* Standard round to integer value functions.  */
 476 extern void real_trunc (REAL_VALUE_TYPE *, format_helper,
 477                         const REAL_VALUE_TYPE *);
 478 extern void real_floor (REAL_VALUE_TYPE *, format_helper,
 479                         const REAL_VALUE_TYPE *);
 480 extern void real_ceil (REAL_VALUE_TYPE *, format_helper,
 481                        const REAL_VALUE_TYPE *);
 482 extern void real_round (REAL_VALUE_TYPE *, format_helper,
 483                         const REAL_VALUE_TYPE *);
 484
 485 /* Set the sign of R to the sign of X.  */
 486 extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 487
 488 /* Check whether the real constant value given is an integer.  */
 489 extern bool real_isinteger (const REAL_VALUE_TYPE *, format_helper);
 490 extern bool real_isinteger (const REAL_VALUE_TYPE *, HOST_WIDE_INT *);
 491
 492 /* Write into BUF the maximum representable finite floating-point
 493    number, (1 - b**-p) * b**emax for a given FP format FMT as a hex
 494    float string.  BUF must be large enough to contain the result.  */
 495 extern void get_max_float (const struct real_format *, char *, size_t);
 496
 497 #ifndef GENERATOR_FILE
 498 /* real related routines.  */
 499 extern wide_int real_to_integer (const REAL_VALUE_TYPE *, bool *, int);
 500 extern void real_from_integer (REAL_VALUE_TYPE *, format_helper,
 501                                const wide_int_ref &, signop);
 502 #endif
 503
 504 #endif /* ! GCC_REAL_H */