gcc/real.h

   1 /* Front-end tree definitions for GNU compiler.
   2    Copyright (C) 1989, 1991, 1994, 1996 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef REAL_H_INCLUDED
  22 #define REAL_H_INCLUDED
  23
  24 /* Define codes for all the float formats that we know of.  */
  25 #define UNKNOWN_FLOAT_FORMAT 0
  26 #define IEEE_FLOAT_FORMAT 1
  27 #define VAX_FLOAT_FORMAT 2
  28 #define IBM_FLOAT_FORMAT 3
  29
  30 /* Default to IEEE float if not specified.  Nearly all machines use it.  */
  31
  32 #ifndef TARGET_FLOAT_FORMAT
  33 #define TARGET_FLOAT_FORMAT     IEEE_FLOAT_FORMAT
  34 #endif
  35
  36 #ifndef HOST_FLOAT_FORMAT
  37 #define HOST_FLOAT_FORMAT       IEEE_FLOAT_FORMAT
  38 #endif
  39
  40 #if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
  41 #define REAL_INFINITY
  42 #endif
  43
  44 /* If FLOAT_WORDS_BIG_ENDIAN and HOST_FLOAT_WORDS_BIG_ENDIAN are not defined
  45    in the header files, then this implies the word-endianness is the same as
  46    for integers.  */
  47
  48 /* This is defined 0 or 1, like WORDS_BIG_ENDIAN.  */
  49 #ifndef FLOAT_WORDS_BIG_ENDIAN
  50 #define FLOAT_WORDS_BIG_ENDIAN WORDS_BIG_ENDIAN
  51 #endif
  52
  53 /* This is defined 0 or 1, unlike HOST_WORDS_BIG_ENDIAN.  */
  54 #ifndef HOST_FLOAT_WORDS_BIG_ENDIAN
  55 #ifdef HOST_WORDS_BIG_ENDIAN
  56 #define HOST_FLOAT_WORDS_BIG_ENDIAN 1
  57 #else
  58 #define HOST_FLOAT_WORDS_BIG_ENDIAN 0
  59 #endif
  60 #endif
  61
  62 /* Defining REAL_ARITHMETIC invokes a floating point emulator
  63    that can produce a target machine format differing by more
  64    than just endian-ness from the host's format.  The emulator
  65    is also used to support extended real XFmode.  */
  66 #ifndef LONG_DOUBLE_TYPE_SIZE
  67 #define LONG_DOUBLE_TYPE_SIZE 64
  68 #endif
  69 #if (LONG_DOUBLE_TYPE_SIZE == 96) || (LONG_DOUBLE_TYPE_SIZE == 128)
  70 #ifndef REAL_ARITHMETIC
  71 #define REAL_ARITHMETIC
  72 #endif
  73 #endif
  74 #ifdef REAL_ARITHMETIC
  75 /* **** Start of software floating point emulator interface macros **** */
  76
  77 /* Support 80-bit extended real XFmode if LONG_DOUBLE_TYPE_SIZE
  78    has been defined to be 96 in the tm.h machine file. */
  79 #if (LONG_DOUBLE_TYPE_SIZE == 96)
  80 #define REAL_IS_NOT_DOUBLE
  81 #define REAL_ARITHMETIC
  82 typedef struct {
  83   HOST_WIDE_INT r[(11 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
  84 } realvaluetype;
  85 #define REAL_VALUE_TYPE realvaluetype
  86
  87 #else /* no XFmode support */
  88
  89 #if (LONG_DOUBLE_TYPE_SIZE == 128)
  90
  91 #define REAL_IS_NOT_DOUBLE
  92 #define REAL_ARITHMETIC
  93 typedef struct {
  94   HOST_WIDE_INT r[(19 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
  95 } realvaluetype;
  96 #define REAL_VALUE_TYPE realvaluetype
  97
  98 #else /* not TFmode */
  99
 100 #if HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
 101 /* If no XFmode support, then a REAL_VALUE_TYPE is 64 bits wide
 102    but it is not necessarily a host machine double. */
 103 #define REAL_IS_NOT_DOUBLE
 104 typedef struct {
 105   HOST_WIDE_INT r[(7 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
 106 } realvaluetype;
 107 #define REAL_VALUE_TYPE realvaluetype
 108 #else
 109 /* If host and target formats are compatible, then a REAL_VALUE_TYPE
 110    is actually a host machine double. */
 111 #define REAL_VALUE_TYPE double
 112 #endif
 113
 114 #endif /* no TFmode support */
 115 #endif /* no XFmode support */
 116
 117 extern int significand_size     PROTO((enum machine_mode));
 118
 119 /* If emulation has been enabled by defining REAL_ARITHMETIC or by
 120    setting LONG_DOUBLE_TYPE_SIZE to 96 or 128, then define macros so that
 121    they invoke emulator functions. This will succeed only if the machine
 122    files have been updated to use these macros in place of any
 123    references to host machine `double' or `float' types.  */
 124 #ifdef REAL_ARITHMETIC
 125 #undef REAL_ARITHMETIC
 126 #define REAL_ARITHMETIC(value, code, d1, d2) \
 127   earith (&(value), (code), &(d1), &(d2))
 128
 129 /* Declare functions in real.c. */
 130 extern void earith              PROTO((REAL_VALUE_TYPE *, int,
 131                                        REAL_VALUE_TYPE *, REAL_VALUE_TYPE *));
 132 extern REAL_VALUE_TYPE etrunci  PROTO((REAL_VALUE_TYPE));
 133 extern REAL_VALUE_TYPE etruncui PROTO((REAL_VALUE_TYPE));
 134 extern REAL_VALUE_TYPE ereal_atof PROTO((char *, enum machine_mode));
 135 extern REAL_VALUE_TYPE ereal_negate PROTO((REAL_VALUE_TYPE));
 136 extern HOST_WIDE_INT efixi      PROTO((REAL_VALUE_TYPE));
 137 extern unsigned HOST_WIDE_INT efixui PROTO((REAL_VALUE_TYPE));
 138 extern void ereal_from_int      PROTO((REAL_VALUE_TYPE *,
 139                                        HOST_WIDE_INT, HOST_WIDE_INT,
 140                                        enum machine_mode));
 141 extern void ereal_from_uint     PROTO((REAL_VALUE_TYPE *,
 142                                        unsigned HOST_WIDE_INT,
 143                                        unsigned HOST_WIDE_INT,
 144                                        enum machine_mode));
 145 extern void ereal_to_int        PROTO((HOST_WIDE_INT *, HOST_WIDE_INT *,
 146                                        REAL_VALUE_TYPE));
 147 extern REAL_VALUE_TYPE ereal_ldexp PROTO((REAL_VALUE_TYPE, int));
 148
 149 extern void etartdouble         PROTO((REAL_VALUE_TYPE, long *));
 150 extern void etarldouble         PROTO((REAL_VALUE_TYPE, long *));
 151 extern void etardouble          PROTO((REAL_VALUE_TYPE, long *));
 152 extern long etarsingle          PROTO((REAL_VALUE_TYPE));
 153 extern void ereal_to_decimal    PROTO((REAL_VALUE_TYPE, char *));
 154 extern int ereal_cmp            PROTO((REAL_VALUE_TYPE, REAL_VALUE_TYPE));
 155 extern int ereal_isneg          PROTO((REAL_VALUE_TYPE));
 156 extern REAL_VALUE_TYPE ereal_from_float PROTO((HOST_WIDE_INT));
 157 extern REAL_VALUE_TYPE ereal_from_double PROTO((HOST_WIDE_INT *));
 158
 159 #define REAL_VALUES_EQUAL(x, y) (ereal_cmp ((x), (y)) == 0)
 160 /* true if x < y : */
 161 #define REAL_VALUES_LESS(x, y) (ereal_cmp ((x), (y)) == -1)
 162 #define REAL_VALUE_LDEXP(x, n) ereal_ldexp (x, n)
 163
 164 /* These return REAL_VALUE_TYPE: */
 165 #define REAL_VALUE_RNDZINT(x) (etrunci (x))
 166 #define REAL_VALUE_UNSIGNED_RNDZINT(x) (etruncui (x))
 167 extern REAL_VALUE_TYPE real_value_truncate ();
 168 #define REAL_VALUE_TRUNCATE(mode, x)  real_value_truncate (mode, x)
 169
 170 /* These return HOST_WIDE_INT: */
 171 /* Convert a floating-point value to integer, rounding toward zero.  */
 172 #define REAL_VALUE_FIX(x) (efixi (x))
 173 /* Convert a floating-point value to unsigned integer, rounding
 174    toward zero. */
 175 #define REAL_VALUE_UNSIGNED_FIX(x) (efixui (x))
 176
 177 #define REAL_VALUE_ATOF ereal_atof
 178 #define REAL_VALUE_NEGATE ereal_negate
 179
 180 #define REAL_VALUE_MINUS_ZERO(x) \
 181  ((ereal_cmp (x, dconst0) == 0) && (ereal_isneg (x) != 0 ))
 182
 183 #define REAL_VALUE_TO_INT ereal_to_int
 184
 185 /* Here the cast to HOST_WIDE_INT sign-extends arguments such as ~0.  */
 186 #define REAL_VALUE_FROM_INT(d, lo, hi, mode) \
 187   ereal_from_int (&d, (HOST_WIDE_INT) (lo), (HOST_WIDE_INT) (hi), mode)
 188
 189 #define REAL_VALUE_FROM_UNSIGNED_INT(d, lo, hi, mode) \
 190   ereal_from_uint (&d, lo, hi, mode)
 191
 192 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs. */
 193 #if LONG_DOUBLE_TYPE_SIZE == 96
 194 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) (etarldouble ((IN), (OUT)))
 195 #else
 196 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) (etartdouble ((IN), (OUT)))
 197 #endif
 198 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) (etardouble ((IN), (OUT)))
 199
 200 /* IN is a REAL_VALUE_TYPE.  OUT is a long. */
 201 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) ((OUT) = etarsingle ((IN)))
 202
 203 /* d is an array of HOST_WIDE_INT that holds a double precision
 204    value in the target computer's floating point format. */
 205 #define REAL_VALUE_FROM_TARGET_DOUBLE(d)  (ereal_from_double (d))
 206
 207 /* f is a HOST_WIDE_INT containing a single precision target float value. */
 208 #define REAL_VALUE_FROM_TARGET_SINGLE(f)  (ereal_from_float (f))
 209
 210 /* Conversions to decimal ASCII string.  */
 211 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (ereal_to_decimal (r, s))
 212
 213 #endif /* REAL_ARITHMETIC defined */
 214
 215 /* **** End of software floating point emulator interface macros **** */
 216 #else /* No XFmode or TFmode and REAL_ARITHMETIC not defined */
 217
 218 /* old interface */
 219 #ifdef REAL_ARITHMETIC
 220 /* Defining REAL_IS_NOT_DOUBLE breaks certain initializations
 221    when REAL_ARITHMETIC etc. are not defined.  */
 222
 223 /* Now see if the host and target machines use the same format.
 224    If not, define REAL_IS_NOT_DOUBLE (even if we end up representing
 225    reals as doubles because we have no better way in this cross compiler.)
 226    This turns off various optimizations that can happen when we know the
 227    compiler's float format matches the target's float format.
 228    */
 229 #if HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
 230 #define REAL_IS_NOT_DOUBLE
 231 #ifndef REAL_VALUE_TYPE
 232 typedef struct {
 233     HOST_WIDE_INT r[sizeof (double)/sizeof (HOST_WIDE_INT)];
 234   } realvaluetype;
 235 #define REAL_VALUE_TYPE realvaluetype
 236 #endif /* no REAL_VALUE_TYPE */
 237 #endif /* formats differ */
 238 #endif /* 0 */
 239
 240 #endif /* emulator not used */
 241
 242 /* If we are not cross-compiling, use a `double' to represent the
 243    floating-point value.  Otherwise, use some other type
 244    (probably a struct containing an array of longs).  */
 245 #ifndef REAL_VALUE_TYPE
 246 #define REAL_VALUE_TYPE double
 247 #else
 248 #define REAL_IS_NOT_DOUBLE
 249 #endif
 250
 251 #if HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT
 252
 253 /* Convert a type `double' value in host format first to a type `float'
 254    value in host format and then to a single type `long' value which
 255    is the bitwise equivalent of the `float' value.  */
 256 #ifndef REAL_VALUE_TO_TARGET_SINGLE
 257 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT)                            \
 258 do { float f = (float) (IN);                                            \
 259      (OUT) = *(long *) &f;                                              \
 260    } while (0)
 261 #endif
 262
 263 /* Convert a type `double' value in host format to a pair of type `long'
 264    values which is its bitwise equivalent, but put the two words into
 265    proper word order for the target.  */
 266 #ifndef REAL_VALUE_TO_TARGET_DOUBLE
 267 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT)                            \
 268 do { REAL_VALUE_TYPE in = (IN);  /* Make sure it's not in a register.  */\
 269      if (HOST_FLOAT_WORDS_BIG_ENDIAN == FLOAT_WORDS_BIG_ENDIAN)         \
 270        {                                                                \
 271          (OUT)[0] = ((long *) &in)[0];                                  \
 272          (OUT)[1] = ((long *) &in)[1];                                  \
 273        }                                                                \
 274      else                                                               \
 275        {                                                                \
 276          (OUT)[1] = ((long *) &in)[0];                                  \
 277          (OUT)[0] = ((long *) &in)[1];                                  \
 278        }                                                                \
 279    } while (0)
 280 #endif
 281 #endif /* HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT */
 282
 283 /* In this configuration, double and long double are the same. */
 284 #ifndef REAL_VALUE_TO_TARGET_LONG_DOUBLE
 285 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(a, b) REAL_VALUE_TO_TARGET_DOUBLE (a, b)
 286 #endif
 287
 288 /* Compare two floating-point values for equality.  */
 289 #ifndef REAL_VALUES_EQUAL
 290 #define REAL_VALUES_EQUAL(x, y) ((x) == (y))
 291 #endif
 292
 293 /* Compare two floating-point values for less than.  */
 294 #ifndef REAL_VALUES_LESS
 295 #define REAL_VALUES_LESS(x, y) ((x) < (y))
 296 #endif
 297
 298 /* Truncate toward zero to an integer floating-point value.  */
 299 #ifndef REAL_VALUE_RNDZINT
 300 #define REAL_VALUE_RNDZINT(x) ((double) ((int) (x)))
 301 #endif
 302
 303 /* Truncate toward zero to an unsigned integer floating-point value.  */
 304 #ifndef REAL_VALUE_UNSIGNED_RNDZINT
 305 #define REAL_VALUE_UNSIGNED_RNDZINT(x) ((double) ((unsigned int) (x)))
 306 #endif
 307
 308 /* Convert a floating-point value to integer, rounding toward zero.  */
 309 #ifndef REAL_VALUE_FIX
 310 #define REAL_VALUE_FIX(x) ((int) (x))
 311 #endif
 312
 313 /* Convert a floating-point value to unsigned integer, rounding
 314    toward zero. */
 315 #ifndef REAL_VALUE_UNSIGNED_FIX
 316 #define REAL_VALUE_UNSIGNED_FIX(x) ((unsigned int) (x))
 317 #endif
 318
 319 /* Scale X by Y powers of 2.  */
 320 #ifndef REAL_VALUE_LDEXP
 321 #define REAL_VALUE_LDEXP(x, y) ldexp (x, y)
 322 extern double ldexp ();
 323 #endif
 324
 325 /* Convert the string X to a floating-point value.  */
 326 #ifndef REAL_VALUE_ATOF
 327 #if 1
 328 /* Use real.c to convert decimal numbers to binary, ... */
 329 REAL_VALUE_TYPE ereal_atof ();
 330 #define REAL_VALUE_ATOF(x, s) ereal_atof (x, s)
 331 #else
 332 /* ... or, if you like the host computer's atof, go ahead and use it: */
 333 #define REAL_VALUE_ATOF(x, s) atof (x)
 334 #if defined (MIPSEL) || defined (MIPSEB)
 335 /* MIPS compiler can't handle parens around the function name.
 336    This problem *does not* appear to be connected with any
 337    macro definition for atof.  It does not seem there is one.  */
 338 extern double atof ();
 339 #else
 340 extern double (atof) ();
 341 #endif
 342 #endif
 343 #endif
 344
 345 /* Negate the floating-point value X.  */
 346 #ifndef REAL_VALUE_NEGATE
 347 #define REAL_VALUE_NEGATE(x) (- (x))
 348 #endif
 349
 350 /* Truncate the floating-point value X to mode MODE.  This is correct only
 351    for the most common case where the host and target have objects of the same
 352    size and where `float' is SFmode.  */
 353
 354 /* Don't use REAL_VALUE_TRUNCATE directly--always call real_value_truncate.  */
 355 extern REAL_VALUE_TYPE real_value_truncate ();
 356
 357 #ifndef REAL_VALUE_TRUNCATE
 358 #define REAL_VALUE_TRUNCATE(mode, x) \
 359  (GET_MODE_BITSIZE (mode) == sizeof (float) * HOST_BITS_PER_CHAR        \
 360   ? (float) (x) : (x))
 361 #endif
 362
 363 /* Determine whether a floating-point value X is infinite. */
 364 #ifndef REAL_VALUE_ISINF
 365 #define REAL_VALUE_ISINF(x) (target_isinf (x))
 366 #endif
 367
 368 /* Determine whether a floating-point value X is a NaN. */
 369 #ifndef REAL_VALUE_ISNAN
 370 #define REAL_VALUE_ISNAN(x) (target_isnan (x))
 371 #endif
 372
 373 /* Determine whether a floating-point value X is negative. */
 374 #ifndef REAL_VALUE_NEGATIVE
 375 #define REAL_VALUE_NEGATIVE(x) (target_negative (x))
 376 #endif
 377
 378 /* Determine whether a floating-point value X is minus 0. */
 379 #ifndef REAL_VALUE_MINUS_ZERO
 380 #define REAL_VALUE_MINUS_ZERO(x) ((x) == 0 && REAL_VALUE_NEGATIVE (x))
 381 #endif
 382 \f
 383 /* Constant real values 0, 1, 2, and -1.  */
 384
 385 extern REAL_VALUE_TYPE dconst0;
 386 extern REAL_VALUE_TYPE dconst1;
 387 extern REAL_VALUE_TYPE dconst2;
 388 extern REAL_VALUE_TYPE dconstm1;
 389
 390 /* Union type used for extracting real values from CONST_DOUBLEs
 391    or putting them in.  */
 392
 393 union real_extract
 394 {
 395   REAL_VALUE_TYPE d;
 396   HOST_WIDE_INT i[sizeof (REAL_VALUE_TYPE) / sizeof (HOST_WIDE_INT)];
 397 };
 398
 399 /* For a CONST_DOUBLE:
 400    The usual two ints that hold the value.
 401    For a DImode, that is all there are;
 402     and CONST_DOUBLE_LOW is the low-order word and ..._HIGH the high-order.
 403    For a float, the number of ints varies,
 404     and CONST_DOUBLE_LOW is the one that should come first *in memory*.
 405     So use &CONST_DOUBLE_LOW(r) as the address of an array of ints.  */
 406 #define CONST_DOUBLE_LOW(r) XWINT (r, 2)
 407 #define CONST_DOUBLE_HIGH(r) XWINT (r, 3)
 408
 409 /* Link for chain of all CONST_DOUBLEs in use in current function.  */
 410 #define CONST_DOUBLE_CHAIN(r) XEXP (r, 1)
 411 /* The MEM which represents this CONST_DOUBLE's value in memory,
 412    or const0_rtx if no MEM has been made for it yet,
 413    or cc0_rtx if it is not on the chain.  */
 414 #define CONST_DOUBLE_MEM(r) XEXP (r, 0)
 415
 416 /* Function to return a real value (not a tree node)
 417    from a given integer constant.  */
 418 REAL_VALUE_TYPE real_value_from_int_cst ();
 419
 420 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents.  */
 421
 422 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from)          \
 423 do { union real_extract u;                              \
 424      bcopy ((char *) &CONST_DOUBLE_LOW ((from)), (char *) &u, sizeof u); \
 425      to = u.d; } while (0)
 426
 427 /* Return a CONST_DOUBLE with value R and mode M.  */
 428
 429 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) immed_real_const_1 (r,  m)
 430 extern struct rtx_def *immed_real_const_1       PROTO((REAL_VALUE_TYPE,
 431                                                        enum machine_mode));
 432
 433
 434 /* Convert a floating point value `r', that can be interpreted
 435    as a host machine float or double, to a decimal ASCII string `s'
 436    using printf format string `fmt'.  */
 437 #ifndef REAL_VALUE_TO_DECIMAL
 438 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (sprintf (s, fmt, r))
 439 #endif
 440
 441 /* Replace R by 1/R in the given machine mode, if the result is exact.  */
 442 extern int exact_real_inverse PROTO((enum machine_mode, REAL_VALUE_TYPE *));
 443
 444 #endif /* Not REAL_H_INCLUDED */