gcc/real.h

   1 /* Definitions of floating-point access for GNU compiler.
   2    Copyright (C) 1989, 1991, 1994, 1996, 1997, 1998,
   3    1999, 2000 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, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #ifndef GCC_REAL_H
  23 #define GCC_REAL_H
  24
  25 /* Define codes for all the float formats that we know of.  */
  26 #define UNKNOWN_FLOAT_FORMAT 0
  27 #define IEEE_FLOAT_FORMAT 1
  28 #define VAX_FLOAT_FORMAT 2
  29 #define IBM_FLOAT_FORMAT 3
  30 #define C4X_FLOAT_FORMAT 4
  31
  32 /* Default to IEEE float if not specified.  Nearly all machines use it.  */
  33
  34 #ifndef TARGET_FLOAT_FORMAT
  35 #define TARGET_FLOAT_FORMAT     IEEE_FLOAT_FORMAT
  36 #endif
  37
  38 #ifndef HOST_FLOAT_FORMAT
  39 #define HOST_FLOAT_FORMAT       IEEE_FLOAT_FORMAT
  40 #endif
  41
  42 #ifndef INTEL_EXTENDED_IEEE_FORMAT
  43 #define INTEL_EXTENDED_IEEE_FORMAT 0
  44 #endif
  45
  46 #if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
  47 #define REAL_INFINITY
  48 #endif
  49
  50 /* If FLOAT_WORDS_BIG_ENDIAN and HOST_FLOAT_WORDS_BIG_ENDIAN are not defined
  51    in the header files, then this implies the word-endianness is the same as
  52    for integers.  */
  53
  54 /* This is defined 0 or 1, like WORDS_BIG_ENDIAN.  */
  55 #ifndef FLOAT_WORDS_BIG_ENDIAN
  56 #define FLOAT_WORDS_BIG_ENDIAN WORDS_BIG_ENDIAN
  57 #endif
  58
  59 /* This is defined 0 or 1, unlike HOST_WORDS_BIG_ENDIAN.  */
  60 #ifndef HOST_FLOAT_WORDS_BIG_ENDIAN
  61 #ifdef HOST_WORDS_BIG_ENDIAN
  62 #define HOST_FLOAT_WORDS_BIG_ENDIAN 1
  63 #else
  64 #define HOST_FLOAT_WORDS_BIG_ENDIAN 0
  65 #endif
  66 #endif
  67
  68 /* Defining REAL_ARITHMETIC invokes a floating point emulator
  69    that can produce a target machine format differing by more
  70    than just endian-ness from the host's format.  The emulator
  71    is also used to support extended real XFmode.  */
  72 #ifndef LONG_DOUBLE_TYPE_SIZE
  73 #define LONG_DOUBLE_TYPE_SIZE 64
  74 #endif
  75 /* MAX_LONG_DOUBLE_TYPE_SIZE is a constant tested by #if.
  76    LONG_DOUBLE_TYPE_SIZE can vary at compiler run time.
  77    So long as macros like REAL_VALUE_TO_TARGET_LONG_DOUBLE cannot
  78    vary too, however, then XFmode and TFmode long double
  79    cannot both be supported at the same time.  */
  80 #ifndef MAX_LONG_DOUBLE_TYPE_SIZE
  81 #define MAX_LONG_DOUBLE_TYPE_SIZE LONG_DOUBLE_TYPE_SIZE
  82 #endif
  83 #if (MAX_LONG_DOUBLE_TYPE_SIZE == 96) || (MAX_LONG_DOUBLE_TYPE_SIZE == 128)
  84 #ifndef REAL_ARITHMETIC
  85 #define REAL_ARITHMETIC
  86 #endif
  87 #endif
  88 #ifdef REAL_ARITHMETIC
  89 /* **** Start of software floating point emulator interface macros **** */
  90
  91 /* Support 80-bit extended real XFmode if LONG_DOUBLE_TYPE_SIZE
  92    has been defined to be 96 in the tm.h machine file.  */
  93 #if (MAX_LONG_DOUBLE_TYPE_SIZE == 96)
  94 #define REAL_IS_NOT_DOUBLE
  95 #define REAL_ARITHMETIC
  96 typedef struct {
  97   HOST_WIDE_INT r[(11 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
  98 } realvaluetype;
  99 #define REAL_VALUE_TYPE realvaluetype
 100
 101 #else /* no XFmode support */
 102
 103 #if (MAX_LONG_DOUBLE_TYPE_SIZE == 128)
 104
 105 #define REAL_IS_NOT_DOUBLE
 106 #define REAL_ARITHMETIC
 107 typedef struct {
 108   HOST_WIDE_INT r[(19 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
 109 } realvaluetype;
 110 #define REAL_VALUE_TYPE realvaluetype
 111
 112 #else /* not TFmode */
 113
 114 #if HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
 115 /* If no XFmode support, then a REAL_VALUE_TYPE is 64 bits wide
 116    but it is not necessarily a host machine double.  */
 117 #define REAL_IS_NOT_DOUBLE
 118 typedef struct {
 119   HOST_WIDE_INT r[(7 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
 120 } realvaluetype;
 121 #define REAL_VALUE_TYPE realvaluetype
 122 #else
 123 /* If host and target formats are compatible, then a REAL_VALUE_TYPE
 124    is actually a host machine double.  */
 125 #define REAL_VALUE_TYPE double
 126 #endif
 127
 128 #endif /* no TFmode support */
 129 #endif /* no XFmode support */
 130
 131 extern unsigned int significand_size    PARAMS ((enum machine_mode));
 132
 133 /* If emulation has been enabled by defining REAL_ARITHMETIC or by
 134    setting LONG_DOUBLE_TYPE_SIZE to 96 or 128, then define macros so that
 135    they invoke emulator functions. This will succeed only if the machine
 136    files have been updated to use these macros in place of any
 137    references to host machine `double' or `float' types.  */
 138 #ifdef REAL_ARITHMETIC
 139 #undef REAL_ARITHMETIC
 140 #define REAL_ARITHMETIC(value, code, d1, d2) \
 141   earith (&(value), (code), &(d1), &(d2))
 142
 143 /* Declare functions in real.c.  */
 144 extern void earith              PARAMS ((REAL_VALUE_TYPE *, int,
 145                                        REAL_VALUE_TYPE *, REAL_VALUE_TYPE *));
 146 extern REAL_VALUE_TYPE etrunci  PARAMS ((REAL_VALUE_TYPE));
 147 extern REAL_VALUE_TYPE etruncui PARAMS ((REAL_VALUE_TYPE));
 148 extern REAL_VALUE_TYPE ereal_negate PARAMS ((REAL_VALUE_TYPE));
 149 extern HOST_WIDE_INT efixi      PARAMS ((REAL_VALUE_TYPE));
 150 extern unsigned HOST_WIDE_INT efixui PARAMS ((REAL_VALUE_TYPE));
 151 extern void ereal_from_int      PARAMS ((REAL_VALUE_TYPE *,
 152                                        HOST_WIDE_INT, HOST_WIDE_INT,
 153                                        enum machine_mode));
 154 extern void ereal_from_uint     PARAMS ((REAL_VALUE_TYPE *,
 155                                        unsigned HOST_WIDE_INT,
 156                                        unsigned HOST_WIDE_INT,
 157                                        enum machine_mode));
 158 extern void ereal_to_int        PARAMS ((HOST_WIDE_INT *, HOST_WIDE_INT *,
 159                                        REAL_VALUE_TYPE));
 160 extern REAL_VALUE_TYPE ereal_ldexp PARAMS ((REAL_VALUE_TYPE, int));
 161
 162 extern void etartdouble         PARAMS ((REAL_VALUE_TYPE, long *));
 163 extern void etarldouble         PARAMS ((REAL_VALUE_TYPE, long *));
 164 extern void etardouble          PARAMS ((REAL_VALUE_TYPE, long *));
 165 extern long etarsingle          PARAMS ((REAL_VALUE_TYPE));
 166 extern void ereal_to_decimal    PARAMS ((REAL_VALUE_TYPE, char *));
 167 extern int ereal_cmp            PARAMS ((REAL_VALUE_TYPE, REAL_VALUE_TYPE));
 168 extern int ereal_isneg          PARAMS ((REAL_VALUE_TYPE));
 169 extern REAL_VALUE_TYPE ereal_unto_float PARAMS ((long));
 170 extern REAL_VALUE_TYPE ereal_unto_double PARAMS ((long *));
 171 extern REAL_VALUE_TYPE ereal_from_float PARAMS ((HOST_WIDE_INT));
 172 extern REAL_VALUE_TYPE ereal_from_double PARAMS ((HOST_WIDE_INT *));
 173
 174 #define REAL_VALUES_EQUAL(x, y) (ereal_cmp ((x), (y)) == 0)
 175 /* true if x < y : */
 176 #define REAL_VALUES_LESS(x, y) (ereal_cmp ((x), (y)) == -1)
 177 #define REAL_VALUE_LDEXP(x, n) ereal_ldexp (x, n)
 178
 179 /* These return REAL_VALUE_TYPE: */
 180 #define REAL_VALUE_RNDZINT(x) (etrunci (x))
 181 #define REAL_VALUE_UNSIGNED_RNDZINT(x) (etruncui (x))
 182 #define REAL_VALUE_TRUNCATE(mode, x)  real_value_truncate (mode, x)
 183
 184 /* These return HOST_WIDE_INT: */
 185 /* Convert a floating-point value to integer, rounding toward zero.  */
 186 #define REAL_VALUE_FIX(x) (efixi (x))
 187 /* Convert a floating-point value to unsigned integer, rounding
 188    toward zero.  */
 189 #define REAL_VALUE_UNSIGNED_FIX(x) (efixui (x))
 190
 191 /* Convert ASCII string S to floating point in mode M.
 192    Decimal input uses ATOF.  Hexadecimal uses HTOF.  */
 193 #define REAL_VALUE_ATOF(s,m) ereal_atof(s,m)
 194 #define REAL_VALUE_HTOF(s,m) ereal_atof(s,m)
 195
 196 #define REAL_VALUE_NEGATE ereal_negate
 197
 198 #define REAL_VALUE_MINUS_ZERO(x) \
 199  ((ereal_cmp (x, dconst0) == 0) && (ereal_isneg (x) != 0 ))
 200
 201 #define REAL_VALUE_TO_INT ereal_to_int
 202
 203 /* Here the cast to HOST_WIDE_INT sign-extends arguments such as ~0.  */
 204 #define REAL_VALUE_FROM_INT(d, lo, hi, mode) \
 205   ereal_from_int (&d, (HOST_WIDE_INT) (lo), (HOST_WIDE_INT) (hi), mode)
 206
 207 #define REAL_VALUE_FROM_UNSIGNED_INT(d, lo, hi, mode) \
 208   ereal_from_uint (&d, lo, hi, mode)
 209
 210 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 211 #if (INTEL_EXTENDED_IEEE_FORMAT != 0) && (MAX_LONG_DOUBLE_TYPE_SIZE == 128)
 212 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) (etarldouble ((IN), (OUT)))
 213 #else
 214 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)               \
 215    (LONG_DOUBLE_TYPE_SIZE == 64 ? etardouble ((IN), (OUT))      \
 216     : LONG_DOUBLE_TYPE_SIZE == 96 ? etarldouble ((IN), (OUT))   \
 217     : LONG_DOUBLE_TYPE_SIZE == 128 ? etartdouble ((IN), (OUT))  \
 218     : abort())
 219 #endif
 220 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) (etardouble ((IN), (OUT)))
 221
 222 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 223 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) ((OUT) = etarsingle ((IN)))
 224
 225 /* Inverse of REAL_VALUE_TO_TARGET_DOUBLE.  */
 226 #define REAL_VALUE_UNTO_TARGET_DOUBLE(d)  (ereal_unto_double (d))
 227
 228 /* Inverse of REAL_VALUE_TO_TARGET_SINGLE.  */
 229 #define REAL_VALUE_UNTO_TARGET_SINGLE(f)  (ereal_unto_float (f))
 230
 231 /* d is an array of HOST_WIDE_INT that holds a double precision
 232    value in the target computer's floating point format.  */
 233 #define REAL_VALUE_FROM_TARGET_DOUBLE(d)  (ereal_from_double (d))
 234
 235 /* f is a HOST_WIDE_INT containing a single precision target float value.  */
 236 #define REAL_VALUE_FROM_TARGET_SINGLE(f)  (ereal_from_float (f))
 237
 238 /* Conversions to decimal ASCII string.  */
 239 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (ereal_to_decimal (r, s))
 240
 241 #endif /* REAL_ARITHMETIC defined */
 242
 243 /* **** End of software floating point emulator interface macros **** */
 244 #else /* No XFmode or TFmode and REAL_ARITHMETIC not defined */
 245
 246 /* old interface */
 247 #ifdef REAL_ARITHMETIC
 248 /* Defining REAL_IS_NOT_DOUBLE breaks certain initializations
 249    when REAL_ARITHMETIC etc. are not defined.  */
 250
 251 /* Now see if the host and target machines use the same format.
 252    If not, define REAL_IS_NOT_DOUBLE (even if we end up representing
 253    reals as doubles because we have no better way in this cross compiler.)
 254    This turns off various optimizations that can happen when we know the
 255    compiler's float format matches the target's float format.
 256    */
 257 #if HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
 258 #define REAL_IS_NOT_DOUBLE
 259 #ifndef REAL_VALUE_TYPE
 260 typedef struct {
 261     HOST_WIDE_INT r[sizeof (double)/sizeof (HOST_WIDE_INT)];
 262   } realvaluetype;
 263 #define REAL_VALUE_TYPE realvaluetype
 264 #endif /* no REAL_VALUE_TYPE */
 265 #endif /* formats differ */
 266 #endif /* 0 */
 267
 268 #endif /* emulator not used */
 269
 270 /* If we are not cross-compiling, use a `double' to represent the
 271    floating-point value.  Otherwise, use some other type
 272    (probably a struct containing an array of longs).  */
 273 #ifndef REAL_VALUE_TYPE
 274 #define REAL_VALUE_TYPE double
 275 #else
 276 #define REAL_IS_NOT_DOUBLE
 277 #endif
 278
 279 #if HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT
 280
 281 /* Convert a type `double' value in host format first to a type `float'
 282    value in host format and then to a single type `long' value which
 283    is the bitwise equivalent of the `float' value.  */
 284 #ifndef REAL_VALUE_TO_TARGET_SINGLE
 285 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT)            \
 286 do {                                                    \
 287   union {                                               \
 288     float f;                                            \
 289     HOST_WIDE_INT l;                                    \
 290   } u;                                                  \
 291   if (sizeof(HOST_WIDE_INT) < sizeof(float))            \
 292     abort();                                            \
 293   u.l = 0;                                              \
 294   u.f = (IN);                                           \
 295   (OUT) = u.l;                                          \
 296 } while (0)
 297 #endif
 298
 299 /* Convert a type `double' value in host format to a pair of type `long'
 300    values which is its bitwise equivalent, but put the two words into
 301    proper word order for the target.  */
 302 #ifndef REAL_VALUE_TO_TARGET_DOUBLE
 303 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT)                            \
 304 do {                                                                    \
 305   union {                                                               \
 306     REAL_VALUE_TYPE f;                                                  \
 307     HOST_WIDE_INT l[2];                                                 \
 308   } u;                                                                  \
 309   if (sizeof(HOST_WIDE_INT) * 2 < sizeof(REAL_VALUE_TYPE))              \
 310     abort();                                                            \
 311   u.l[0] = u.l[1] = 0;                                                  \
 312   u.f = (IN);                                                           \
 313   if (HOST_FLOAT_WORDS_BIG_ENDIAN == FLOAT_WORDS_BIG_ENDIAN)            \
 314     (OUT)[0] = u.l[0], (OUT)[1] = u.l[1];                               \
 315   else                                                                  \
 316     (OUT)[1] = u.l[0], (OUT)[0] = u.l[1];                               \
 317 } while (0)
 318 #endif
 319 #endif /* HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT */
 320
 321 /* In this configuration, double and long double are the same.  */
 322 #ifndef REAL_VALUE_TO_TARGET_LONG_DOUBLE
 323 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(a, b) REAL_VALUE_TO_TARGET_DOUBLE (a, b)
 324 #endif
 325
 326 /* Compare two floating-point objects for bitwise identity.
 327    This is not the same as comparing for equality on IEEE hosts:
 328    -0.0 equals 0.0 but they are not identical, and conversely
 329    two NaNs might be identical but they cannot be equal.  */
 330 #define REAL_VALUES_IDENTICAL(x, y) \
 331   (!memcmp ((char *) &(x), (char *) &(y), sizeof (REAL_VALUE_TYPE)))
 332
 333 /* Compare two floating-point values for equality.  */
 334 #ifndef REAL_VALUES_EQUAL
 335 #define REAL_VALUES_EQUAL(x, y) ((x) == (y))
 336 #endif
 337
 338 /* Compare two floating-point values for less than.  */
 339 #ifndef REAL_VALUES_LESS
 340 #define REAL_VALUES_LESS(x, y) ((x) < (y))
 341 #endif
 342
 343 /* Truncate toward zero to an integer floating-point value.  */
 344 #ifndef REAL_VALUE_RNDZINT
 345 #define REAL_VALUE_RNDZINT(x) ((double) ((int) (x)))
 346 #endif
 347
 348 /* Truncate toward zero to an unsigned integer floating-point value.  */
 349 #ifndef REAL_VALUE_UNSIGNED_RNDZINT
 350 #define REAL_VALUE_UNSIGNED_RNDZINT(x) ((double) ((unsigned int) (x)))
 351 #endif
 352
 353 /* Convert a floating-point value to integer, rounding toward zero.  */
 354 #ifndef REAL_VALUE_FIX
 355 #define REAL_VALUE_FIX(x) ((int) (x))
 356 #endif
 357
 358 /* Convert a floating-point value to unsigned integer, rounding
 359    toward zero.  */
 360 #ifndef REAL_VALUE_UNSIGNED_FIX
 361 #define REAL_VALUE_UNSIGNED_FIX(x) ((unsigned int) (x))
 362 #endif
 363
 364 /* Scale X by Y powers of 2.  */
 365 #ifndef REAL_VALUE_LDEXP
 366 #define REAL_VALUE_LDEXP(x, y) ldexp (x, y)
 367 extern double ldexp PARAMS ((double, int));
 368 #endif
 369
 370 /* Convert the string X to a floating-point value.  */
 371 #ifndef REAL_VALUE_ATOF
 372 #if 1
 373 /* Use real.c to convert decimal numbers to binary, ...  */
 374 #define REAL_VALUE_ATOF(x, s) ereal_atof (x, s)
 375 /* Could use ereal_atof here for hexadecimal floats too, but real_hex_to_f
 376    is OK and it uses faster native fp arithmetic.  */
 377 /* #define REAL_VALUE_HTOF(x, s) ereal_atof (x, s) */
 378 #else
 379 /* ... or, if you like the host computer's atof, go ahead and use it: */
 380 #define REAL_VALUE_ATOF(x, s) atof (x)
 381 #if defined (MIPSEL) || defined (MIPSEB)
 382 /* MIPS compiler can't handle parens around the function name.
 383    This problem *does not* appear to be connected with any
 384    macro definition for atof.  It does not seem there is one.  */
 385 extern double atof ();
 386 #else
 387 extern double (atof) ();
 388 #endif
 389 #endif
 390 #endif
 391
 392 /* Hexadecimal floating constant input for use with host computer's
 393    fp arithmetic.  */
 394 #ifndef REAL_VALUE_HTOF
 395 extern REAL_VALUE_TYPE real_hex_to_f PARAMS ((const char *,
 396                                               enum machine_mode));
 397 #define REAL_VALUE_HTOF(s,m) real_hex_to_f(s,m)
 398 #endif
 399
 400 /* Negate the floating-point value X.  */
 401 #ifndef REAL_VALUE_NEGATE
 402 #define REAL_VALUE_NEGATE(x) (- (x))
 403 #endif
 404
 405 /* Truncate the floating-point value X to mode MODE.  This is correct only
 406    for the most common case where the host and target have objects of the same
 407    size and where `float' is SFmode.  */
 408
 409 /* Don't use REAL_VALUE_TRUNCATE directly--always call real_value_truncate.  */
 410 extern REAL_VALUE_TYPE real_value_truncate PARAMS ((enum machine_mode,
 411                                                   REAL_VALUE_TYPE));
 412
 413 #ifndef REAL_VALUE_TRUNCATE
 414 #define REAL_VALUE_TRUNCATE(mode, x) \
 415  (GET_MODE_BITSIZE (mode) == sizeof (float) * HOST_BITS_PER_CHAR        \
 416   ? (float) (x) : (x))
 417 #endif
 418
 419 /* Determine whether a floating-point value X is infinite.  */
 420 #ifndef REAL_VALUE_ISINF
 421 #define REAL_VALUE_ISINF(x) (target_isinf (x))
 422 #endif
 423
 424 /* Determine whether a floating-point value X is a NaN.  */
 425 #ifndef REAL_VALUE_ISNAN
 426 #define REAL_VALUE_ISNAN(x) (target_isnan (x))
 427 #endif
 428
 429 /* Determine whether a floating-point value X is negative.  */
 430 #ifndef REAL_VALUE_NEGATIVE
 431 #define REAL_VALUE_NEGATIVE(x) (target_negative (x))
 432 #endif
 433
 434 /* Determine whether a floating-point value X is minus 0.  */
 435 #ifndef REAL_VALUE_MINUS_ZERO
 436 #define REAL_VALUE_MINUS_ZERO(x) ((x) == 0 && REAL_VALUE_NEGATIVE (x))
 437 #endif
 438 \f
 439 /* Constant real values 0, 1, 2, and -1.  */
 440
 441 extern REAL_VALUE_TYPE dconst0;
 442 extern REAL_VALUE_TYPE dconst1;
 443 extern REAL_VALUE_TYPE dconst2;
 444 extern REAL_VALUE_TYPE dconstm1;
 445
 446 /* Union type used for extracting real values from CONST_DOUBLEs
 447    or putting them in.  */
 448
 449 union real_extract
 450 {
 451   REAL_VALUE_TYPE d;
 452   HOST_WIDE_INT i[sizeof (REAL_VALUE_TYPE) / sizeof (HOST_WIDE_INT)];
 453 };
 454
 455 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents.  */
 456 /* Function to return a real value (not a tree node)
 457    from a given integer constant.  */
 458 union tree_node;
 459 REAL_VALUE_TYPE real_value_from_int_cst PARAMS ((union tree_node *,
 460                                                 union tree_node *));
 461
 462 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from)          \
 463 do { union real_extract u;                              \
 464      memcpy (&u, &CONST_DOUBLE_LOW ((from)), sizeof u); \
 465      to = u.d; } while (0)
 466
 467 /* Return a CONST_DOUBLE with value R and mode M.  */
 468
 469 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) immed_real_const_1 (r,  m)
 470 extern struct rtx_def *immed_real_const_1       PARAMS ((REAL_VALUE_TYPE,
 471                                                        enum machine_mode));
 472
 473
 474 /* Convert a floating point value `r', that can be interpreted
 475    as a host machine float or double, to a decimal ASCII string `s'
 476    using printf format string `fmt'.  */
 477 #ifndef REAL_VALUE_TO_DECIMAL
 478 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (sprintf (s, fmt, r))
 479 #endif
 480
 481 /* Replace R by 1/R in the given machine mode, if the result is exact.  */
 482 extern int exact_real_inverse   PARAMS ((enum machine_mode, REAL_VALUE_TYPE *));
 483 extern int target_isnan         PARAMS ((REAL_VALUE_TYPE));
 484 extern int target_isinf         PARAMS ((REAL_VALUE_TYPE));
 485 extern int target_negative      PARAMS ((REAL_VALUE_TYPE));
 486 extern void debug_real          PARAMS ((REAL_VALUE_TYPE));
 487 extern REAL_VALUE_TYPE ereal_atof PARAMS ((const char *, enum machine_mode));
 488
 489 #endif /* ! GCC_REAL_H */