gcc/real.h

   1 /* Definitions of floating-point access for GNU compiler.
   2    Copyright (C) 1989-2021 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   /* 1 if number is decimal floating point.  */
  45   unsigned int decimal : 1;
  46   /* 1 if number is negative.  */
  47   unsigned int sign : 1;
  48   /* 1 if number is signalling.  */
  49   unsigned int signalling : 1;
  50   /* 1 if number is canonical
  51   All are generally used for handling cases in real.c.  */
  52   unsigned int canonical : 1;
  53   /* unbiased exponent of the number.  */
  54   unsigned int uexp : EXP_BITS;
  55   /* significand of the number.  */
  56   unsigned long sig[SIGSZ];
  57 };
  58
  59 #define REAL_EXP(REAL) \
  60   ((int)((REAL)->uexp ^ (unsigned int)(1 << (EXP_BITS - 1))) \
  61    - (1 << (EXP_BITS - 1)))
  62 #define SET_REAL_EXP(REAL, EXP) \
  63   ((REAL)->uexp = ((unsigned int)(EXP) & (unsigned int)((1 << EXP_BITS) - 1)))
  64
  65 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it
  66    needs to be a macro.  We do need to continue to have a structure tag
  67    so that other headers can forward declare it.  */
  68 #define REAL_VALUE_TYPE struct real_value
  69
  70 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in
  71    consecutive "w" slots.  Moreover, we've got to compute the number of "w"
  72    slots at preprocessor time, which means we can't use sizeof.  Guess.  */
  73
  74 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32)
  75 #define REAL_WIDTH \
  76   (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \
  77    + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */
  78
  79 /* Verify the guess.  */
  80 extern char test_real_width
  81   [sizeof (REAL_VALUE_TYPE) <= REAL_WIDTH * sizeof (HOST_WIDE_INT) ? 1 : -1];
  82
  83 /* Calculate the format for CONST_DOUBLE.  We need as many slots as
  84    are necessary to overlay a REAL_VALUE_TYPE on them.  This could be
  85    as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE).
  86
  87    A number of places assume that there are always at least two 'w'
  88    slots in a CONST_DOUBLE, so we provide them even if one would suffice.  */
  89
  90 #if REAL_WIDTH == 1
  91 # define CONST_DOUBLE_FORMAT     "ww"
  92 #else
  93 # if REAL_WIDTH == 2
  94 #  define CONST_DOUBLE_FORMAT    "ww"
  95 # else
  96 #  if REAL_WIDTH == 3
  97 #   define CONST_DOUBLE_FORMAT   "www"
  98 #  else
  99 #   if REAL_WIDTH == 4
 100 #    define CONST_DOUBLE_FORMAT  "wwww"
 101 #   else
 102 #    if REAL_WIDTH == 5
 103 #     define CONST_DOUBLE_FORMAT "wwwww"
 104 #    else
 105 #     if REAL_WIDTH == 6
 106 #      define CONST_DOUBLE_FORMAT "wwwwww"
 107 #     else
 108        #error "REAL_WIDTH > 6 not supported"
 109 #     endif
 110 #    endif
 111 #   endif
 112 #  endif
 113 # endif
 114 #endif
 115
 116
 117 /* Describes the properties of the specific target format in use.  */
 118 struct real_format
 119 {
 120   /* Move to and from the target bytes.  */
 121   void (*encode) (const struct real_format *, long *,
 122                   const REAL_VALUE_TYPE *);
 123   void (*decode) (const struct real_format *, REAL_VALUE_TYPE *,
 124                   const long *);
 125
 126   /* The radix of the exponent and digits of the significand.  */
 127   int b;
 128
 129   /* Size of the significand in digits of radix B.  */
 130   int p;
 131
 132   /* Size of the significant of a NaN, in digits of radix B.  */
 133   int pnan;
 134
 135   /* The minimum negative integer, x, such that b**(x-1) is normalized.  */
 136   int emin;
 137
 138   /* The maximum integer, x, such that b**(x-1) is representable.  */
 139   int emax;
 140
 141   /* The bit position of the sign bit, for determining whether a value
 142      is positive/negative, or -1 for a complex encoding.  */
 143   int signbit_ro;
 144
 145   /* The bit position of the sign bit, for changing the sign of a number,
 146      or -1 for a complex encoding.  */
 147   int signbit_rw;
 148
 149   /* If this is an IEEE interchange format, the number of bits in the
 150      format; otherwise, if it is an IEEE extended format, one more
 151      than the greatest number of bits in an interchange format it
 152      extends; otherwise 0.  Formats need not follow the IEEE 754-2008
 153      recommended practice regarding how signaling NaNs are identified,
 154      and may vary in the choice of default NaN, but must follow other
 155      IEEE practice regarding having NaNs, infinities and subnormal
 156      values, and the relation of minimum and maximum exponents, and,
 157      for interchange formats, the details of the encoding.  */
 158   int ieee_bits;
 159
 160   /* Default rounding mode for operations on this format.  */
 161   bool round_towards_zero;
 162   bool has_sign_dependent_rounding;
 163
 164   /* Properties of the format.  */
 165   bool has_nans;
 166   bool has_inf;
 167   bool has_denorm;
 168   bool has_signed_zero;
 169   bool qnan_msb_set;
 170   bool canonical_nan_lsbs_set;
 171   const char *name;
 172 };
 173
 174
 175 /* The target format used for each floating point mode.
 176    Float modes are followed by decimal float modes, with entries for
 177    float modes indexed by (MODE - first float mode), and entries for
 178    decimal float modes indexed by (MODE - first decimal float mode) +
 179    the number of float modes.  */
 180 extern const struct real_format *
 181   real_format_for_mode[MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1
 182                        + MAX_MODE_DECIMAL_FLOAT - MIN_MODE_DECIMAL_FLOAT + 1];
 183
 184 #define REAL_MODE_FORMAT(MODE)                                          \
 185   (real_format_for_mode[DECIMAL_FLOAT_MODE_P (MODE)                     \
 186                         ? (((MODE) - MIN_MODE_DECIMAL_FLOAT)            \
 187                            + (MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1))     \
 188                         : GET_MODE_CLASS (MODE) == MODE_FLOAT           \
 189                         ? ((MODE) - MIN_MODE_FLOAT)                     \
 190                         : (gcc_unreachable (), 0)])
 191
 192 #define FLOAT_MODE_FORMAT(MODE) \
 193   (REAL_MODE_FORMAT (as_a <scalar_float_mode> (GET_MODE_INNER (MODE))))
 194
 195 /* The following macro determines whether the floating point format is
 196    composite, i.e. may contain non-consecutive mantissa bits, in which
 197    case compile-time FP overflow may not model run-time overflow.  */
 198 #define MODE_COMPOSITE_P(MODE) \
 199   (FLOAT_MODE_P (MODE) \
 200    && FLOAT_MODE_FORMAT (MODE)->pnan < FLOAT_MODE_FORMAT (MODE)->p)
 201
 202 /* Accessor macros for format properties.  */
 203 #define MODE_HAS_NANS(MODE) \
 204   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_nans)
 205 #define MODE_HAS_INFINITIES(MODE) \
 206   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_inf)
 207 #define MODE_HAS_SIGNED_ZEROS(MODE) \
 208   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_signed_zero)
 209 #define MODE_HAS_SIGN_DEPENDENT_ROUNDING(MODE) \
 210   (FLOAT_MODE_P (MODE) \
 211    && FLOAT_MODE_FORMAT (MODE)->has_sign_dependent_rounding)
 212
 213 /* This class allows functions in this file to accept a floating-point
 214    format as either a mode or an explicit real_format pointer.  In the
 215    former case the mode must be VOIDmode (which means "no particular
 216    format") or must satisfy SCALAR_FLOAT_MODE_P.  */
 217 class format_helper
 218 {
 219 public:
 220   format_helper (const real_format *format) : m_format (format) {}
 221   template<typename T> format_helper (const T &);
 222   const real_format *operator-> () const { return m_format; }
 223   operator const real_format *() const { return m_format; }
 224
 225   bool decimal_p () const { return m_format && m_format->b == 10; }
 226   bool can_represent_integral_type_p (tree type) const;
 227
 228 private:
 229   const real_format *m_format;
 230 };
 231
 232 template<typename T>
 233 inline format_helper::format_helper (const T &m)
 234   : m_format (m == VOIDmode ? 0 : REAL_MODE_FORMAT (m))
 235 {}
 236
 237 /* Declare functions in real.c.  */
 238
 239 /* True if the given mode has a NaN representation and the treatment of
 240    NaN operands is important.  Certain optimizations, such as folding
 241    x * 0 into 0, are not correct for NaN operands, and are normally
 242    disabled for modes with NaNs.  The user can ask for them to be
 243    done anyway using the -funsafe-math-optimizations switch.  */
 244 extern bool HONOR_NANS (machine_mode);
 245 extern bool HONOR_NANS (const_tree);
 246 extern bool HONOR_NANS (const_rtx);
 247
 248 /* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs).  */
 249 extern bool HONOR_SNANS (machine_mode);
 250 extern bool HONOR_SNANS (const_tree);
 251 extern bool HONOR_SNANS (const_rtx);
 252
 253 /* As for HONOR_NANS, but true if the mode can represent infinity and
 254    the treatment of infinite values is important.  */
 255 extern bool HONOR_INFINITIES (machine_mode);
 256 extern bool HONOR_INFINITIES (const_tree);
 257 extern bool HONOR_INFINITIES (const_rtx);
 258
 259 /* Like HONOR_NANS, but true if the given mode distinguishes between
 260    positive and negative zero, and the sign of zero is important.  */
 261 extern bool HONOR_SIGNED_ZEROS (machine_mode);
 262 extern bool HONOR_SIGNED_ZEROS (const_tree);
 263 extern bool HONOR_SIGNED_ZEROS (const_rtx);
 264
 265 /* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
 266    and the rounding mode is important.  */
 267 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (machine_mode);
 268 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_tree);
 269 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_rtx);
 270
 271 /* Binary or unary arithmetic on tree_code.  */
 272 extern bool real_arithmetic (REAL_VALUE_TYPE *, int, const REAL_VALUE_TYPE *,
 273                              const REAL_VALUE_TYPE *);
 274
 275 /* Compare reals by tree_code.  */
 276 extern bool real_compare (int, const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 277
 278 /* Determine whether a floating-point value X is infinite.  */
 279 extern bool real_isinf (const REAL_VALUE_TYPE *);
 280
 281 /* Determine whether a floating-point value X is a NaN.  */
 282 extern bool real_isnan (const REAL_VALUE_TYPE *);
 283
 284 /* Determine whether a floating-point value X is a signaling NaN.  */
 285 extern bool real_issignaling_nan (const REAL_VALUE_TYPE *);
 286
 287 /* Determine whether a floating-point value X is finite.  */
 288 extern bool real_isfinite (const REAL_VALUE_TYPE *);
 289
 290 /* Determine whether a floating-point value X is negative.  */
 291 extern bool real_isneg (const REAL_VALUE_TYPE *);
 292
 293 /* Determine whether a floating-point value X is minus zero.  */
 294 extern bool real_isnegzero (const REAL_VALUE_TYPE *);
 295
 296 /* Test relationships between reals.  */
 297 extern bool real_identical (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 298 extern bool real_equal (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 299 extern bool real_less (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 300
 301 /* Extend or truncate to a new format.  */
 302 extern void real_convert (REAL_VALUE_TYPE *, format_helper,
 303                           const REAL_VALUE_TYPE *);
 304
 305 /* Return true if truncating to NEW is exact.  */
 306 extern bool exact_real_truncate (format_helper, const REAL_VALUE_TYPE *);
 307
 308 /* Render R as a decimal floating point constant.  */
 309 extern void real_to_decimal (char *, const REAL_VALUE_TYPE *, size_t,
 310                              size_t, int);
 311
 312 /* Render R as a decimal floating point constant, rounded so as to be
 313    parsed back to the same value when interpreted in mode MODE.  */
 314 extern void real_to_decimal_for_mode (char *, const REAL_VALUE_TYPE *, size_t,
 315                                       size_t, int, machine_mode);
 316
 317 /* Render R as a hexadecimal floating point constant.  */
 318 extern void real_to_hexadecimal (char *, const REAL_VALUE_TYPE *,
 319                                  size_t, size_t, int);
 320
 321 /* Render R as an integer.  */
 322 extern HOST_WIDE_INT real_to_integer (const REAL_VALUE_TYPE *);
 323
 324 /* Initialize R from a decimal or hexadecimal string.  Return -1 if
 325    the value underflows, +1 if overflows, and 0 otherwise.  */
 326 extern int real_from_string (REAL_VALUE_TYPE *, const char *);
 327 /* Wrapper to allow different internal representation for decimal floats. */
 328 extern void real_from_string3 (REAL_VALUE_TYPE *, const char *, format_helper);
 329
 330 extern long real_to_target (long *, const REAL_VALUE_TYPE *, format_helper);
 331
 332 extern void real_from_target (REAL_VALUE_TYPE *, const long *,
 333                               format_helper);
 334
 335 extern void real_inf (REAL_VALUE_TYPE *);
 336
 337 extern bool real_nan (REAL_VALUE_TYPE *, const char *, int, format_helper);
 338
 339 extern void real_maxval (REAL_VALUE_TYPE *, int, machine_mode);
 340
 341 extern void real_2expN (REAL_VALUE_TYPE *, int, format_helper);
 342
 343 extern unsigned int real_hash (const REAL_VALUE_TYPE *);
 344
 345
 346 /* Target formats defined in real.c.  */
 347 extern const struct real_format ieee_single_format;
 348 extern const struct real_format mips_single_format;
 349 extern const struct real_format motorola_single_format;
 350 extern const struct real_format spu_single_format;
 351 extern const struct real_format ieee_double_format;
 352 extern const struct real_format mips_double_format;
 353 extern const struct real_format motorola_double_format;
 354 extern const struct real_format ieee_extended_motorola_format;
 355 extern const struct real_format ieee_extended_intel_96_format;
 356 extern const struct real_format ieee_extended_intel_96_round_53_format;
 357 extern const struct real_format ieee_extended_intel_128_format;
 358 extern const struct real_format ibm_extended_format;
 359 extern const struct real_format mips_extended_format;
 360 extern const struct real_format ieee_quad_format;
 361 extern const struct real_format mips_quad_format;
 362 extern const struct real_format vax_f_format;
 363 extern const struct real_format vax_d_format;
 364 extern const struct real_format vax_g_format;
 365 extern const struct real_format real_internal_format;
 366 extern const struct real_format decimal_single_format;
 367 extern const struct real_format decimal_double_format;
 368 extern const struct real_format decimal_quad_format;
 369 extern const struct real_format ieee_half_format;
 370 extern const struct real_format arm_half_format;
 371 extern const struct real_format arm_bfloat_half_format;
 372
 373
 374 /* ====================================================================== */
 375 /* Crap.  */
 376
 377 /* Determine whether a floating-point value X is infinite.  */
 378 #define REAL_VALUE_ISINF(x)             real_isinf (&(x))
 379
 380 /* Determine whether a floating-point value X is a NaN.  */
 381 #define REAL_VALUE_ISNAN(x)             real_isnan (&(x))
 382
 383 /* Determine whether a floating-point value X is a signaling NaN.  */
 384 #define REAL_VALUE_ISSIGNALING_NAN(x)  real_issignaling_nan (&(x))
 385
 386 /* Determine whether a floating-point value X is negative.  */
 387 #define REAL_VALUE_NEGATIVE(x)          real_isneg (&(x))
 388
 389 /* Determine whether a floating-point value X is minus zero.  */
 390 #define REAL_VALUE_MINUS_ZERO(x)        real_isnegzero (&(x))
 391
 392 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 393 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)                       \
 394   real_to_target (OUT, &(IN),                                           \
 395                   float_mode_for_size (LONG_DOUBLE_TYPE_SIZE).require ())
 396
 397 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \
 398   real_to_target (OUT, &(IN), float_mode_for_size (64).require ())
 399
 400 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 401 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \
 402   ((OUT) = real_to_target (NULL, &(IN), float_mode_for_size (32).require ()))
 403
 404 /* Real values to IEEE 754 decimal floats.  */
 405
 406 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 407 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \
 408   real_to_target (OUT, &(IN), decimal_float_mode_for_size (128).require ())
 409
 410 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \
 411   real_to_target (OUT, &(IN), decimal_float_mode_for_size (64).require ())
 412
 413 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 414 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \
 415   ((OUT) = real_to_target (NULL, &(IN), \
 416                            decimal_float_mode_for_size (32).require ()))
 417
 418 extern REAL_VALUE_TYPE real_value_truncate (format_helper, REAL_VALUE_TYPE);
 419
 420 extern REAL_VALUE_TYPE real_value_negate (const REAL_VALUE_TYPE *);
 421 extern REAL_VALUE_TYPE real_value_abs (const REAL_VALUE_TYPE *);
 422
 423 extern int significand_size (format_helper);
 424
 425 extern REAL_VALUE_TYPE real_from_string2 (const char *, format_helper);
 426
 427 #define REAL_VALUE_ATOF(s, m) \
 428   real_from_string2 (s, m)
 429
 430 #define CONST_DOUBLE_ATOF(s, m) \
 431   const_double_from_real_value (real_from_string2 (s, m), m)
 432
 433 #define REAL_VALUE_FIX(r) \
 434   real_to_integer (&(r))
 435
 436 /* ??? Not quite right.  */
 437 #define REAL_VALUE_UNSIGNED_FIX(r) \
 438   real_to_integer (&(r))
 439
 440 /* ??? These were added for Paranoia support.  */
 441
 442 /* Return floor log2(R).  */
 443 extern int real_exponent (const REAL_VALUE_TYPE *);
 444
 445 /* R = A * 2**EXP.  */
 446 extern void real_ldexp (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *, int);
 447
 448 /* **** End of software floating point emulator interface macros **** */
 449 \f
 450 /* Constant real values 0, 1, 2, -1 and 0.5.  */
 451
 452 extern REAL_VALUE_TYPE dconst0;
 453 extern REAL_VALUE_TYPE dconst1;
 454 extern REAL_VALUE_TYPE dconst2;
 455 extern REAL_VALUE_TYPE dconstm1;
 456 extern REAL_VALUE_TYPE dconsthalf;
 457
 458 #define dconst_e() (*dconst_e_ptr ())
 459 #define dconst_third() (*dconst_third_ptr ())
 460 #define dconst_quarter() (*dconst_quarter_ptr ())
 461 #define dconst_sixth() (*dconst_sixth_ptr ())
 462 #define dconst_ninth() (*dconst_ninth_ptr ())
 463 #define dconst_sqrt2() (*dconst_sqrt2_ptr ())
 464
 465 /* Function to return the real value special constant 'e'.  */
 466 extern const REAL_VALUE_TYPE * dconst_e_ptr (void);
 467
 468 /* Returns a cached REAL_VALUE_TYPE corresponding to 1/n, for various n.  */
 469 extern const REAL_VALUE_TYPE *dconst_third_ptr (void);
 470 extern const REAL_VALUE_TYPE *dconst_quarter_ptr (void);
 471 extern const REAL_VALUE_TYPE *dconst_sixth_ptr (void);
 472 extern const REAL_VALUE_TYPE *dconst_ninth_ptr (void);
 473
 474 /* Returns the special REAL_VALUE_TYPE corresponding to sqrt(2).  */
 475 extern const REAL_VALUE_TYPE * dconst_sqrt2_ptr (void);
 476
 477 /* Function to return a real value (not a tree node)
 478    from a given integer constant.  */
 479 REAL_VALUE_TYPE real_value_from_int_cst (const_tree, const_tree);
 480
 481 /* Return a CONST_DOUBLE with value R and mode M.  */
 482 extern rtx const_double_from_real_value (REAL_VALUE_TYPE, machine_mode);
 483
 484 /* Replace R by 1/R in the given format, if the result is exact.  */
 485 extern bool exact_real_inverse (format_helper, REAL_VALUE_TYPE *);
 486
 487 /* Return true if arithmetic on values in IMODE that were promoted
 488    from values in TMODE is equivalent to direct arithmetic on values
 489    in TMODE.  */
 490 bool real_can_shorten_arithmetic (machine_mode, machine_mode);
 491
 492 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node.  */
 493 extern tree build_real (tree, REAL_VALUE_TYPE);
 494
 495 /* Likewise, but first truncate the value to the type.  */
 496 extern tree build_real_truncate (tree, REAL_VALUE_TYPE);
 497
 498 /* Calculate R as X raised to the integer exponent N in format FMT.  */
 499 extern bool real_powi (REAL_VALUE_TYPE *, format_helper,
 500                        const REAL_VALUE_TYPE *, HOST_WIDE_INT);
 501
 502 /* Standard round to integer value functions.  */
 503 extern void real_trunc (REAL_VALUE_TYPE *, format_helper,
 504                         const REAL_VALUE_TYPE *);
 505 extern void real_floor (REAL_VALUE_TYPE *, format_helper,
 506                         const REAL_VALUE_TYPE *);
 507 extern void real_ceil (REAL_VALUE_TYPE *, format_helper,
 508                        const REAL_VALUE_TYPE *);
 509 extern void real_round (REAL_VALUE_TYPE *, format_helper,
 510                         const REAL_VALUE_TYPE *);
 511 extern void real_roundeven (REAL_VALUE_TYPE *, format_helper,
 512                             const REAL_VALUE_TYPE *);
 513
 514 /* Set the sign of R to the sign of X.  */
 515 extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 516
 517 /* Check whether the real constant value given is an integer.  */
 518 extern bool real_isinteger (const REAL_VALUE_TYPE *, format_helper);
 519 extern bool real_isinteger (const REAL_VALUE_TYPE *, HOST_WIDE_INT *);
 520
 521 /* Calculate nextafter (X, Y) in format FMT.  */
 522 extern bool real_nextafter (REAL_VALUE_TYPE *, format_helper,
 523                             const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
 524
 525 /* Write into BUF the maximum representable finite floating-point
 526    number, (1 - b**-p) * b**emax for a given FP format FMT as a hex
 527    float string.  BUF must be large enough to contain the result.  */
 528 extern void get_max_float (const struct real_format *, char *, size_t, bool);
 529
 530 #ifndef GENERATOR_FILE
 531 /* real related routines.  */
 532 extern wide_int real_to_integer (const REAL_VALUE_TYPE *, bool *, int);
 533 extern void real_from_integer (REAL_VALUE_TYPE *, format_helper,
 534                                const wide_int_ref &, signop);
 535 #endif
 536
 537 /* Fills r with the largest value such that 1 + r*r won't overflow.
 538    This is used in both sin (atan (x)) and cos (atan(x)) optimizations. */
 539 extern void build_sinatan_real (REAL_VALUE_TYPE *, tree);
 540
 541 #endif /* ! GCC_REAL_H */