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_unto_float PROTO((long));
 157 extern REAL_VALUE_TYPE ereal_unto_double PROTO((long *));
 158 extern REAL_VALUE_TYPE ereal_from_float PROTO((HOST_WIDE_INT));
 159 extern REAL_VALUE_TYPE ereal_from_double PROTO((HOST_WIDE_INT *));
 160
 161 #define REAL_VALUES_EQUAL(x, y) (ereal_cmp ((x), (y)) == 0)
 162 /* true if x < y : */
 163 #define REAL_VALUES_LESS(x, y) (ereal_cmp ((x), (y)) == -1)
 164 #define REAL_VALUE_LDEXP(x, n) ereal_ldexp (x, n)
 165
 166 /* These return REAL_VALUE_TYPE: */
 167 #define REAL_VALUE_RNDZINT(x) (etrunci (x))
 168 #define REAL_VALUE_UNSIGNED_RNDZINT(x) (etruncui (x))
 169 extern REAL_VALUE_TYPE real_value_truncate ();
 170 #define REAL_VALUE_TRUNCATE(mode, x)  real_value_truncate (mode, x)
 171
 172 /* These return HOST_WIDE_INT: */
 173 /* Convert a floating-point value to integer, rounding toward zero.  */
 174 #define REAL_VALUE_FIX(x) (efixi (x))
 175 /* Convert a floating-point value to unsigned integer, rounding
 176    toward zero. */
 177 #define REAL_VALUE_UNSIGNED_FIX(x) (efixui (x))
 178
 179 #define REAL_VALUE_ATOF ereal_atof
 180 #define REAL_VALUE_NEGATE ereal_negate
 181
 182 #define REAL_VALUE_MINUS_ZERO(x) \
 183  ((ereal_cmp (x, dconst0) == 0) && (ereal_isneg (x) != 0 ))
 184
 185 #define REAL_VALUE_TO_INT ereal_to_int
 186
 187 /* Here the cast to HOST_WIDE_INT sign-extends arguments such as ~0.  */
 188 #define REAL_VALUE_FROM_INT(d, lo, hi, mode) \
 189   ereal_from_int (&d, (HOST_WIDE_INT) (lo), (HOST_WIDE_INT) (hi), mode)
 190
 191 #define REAL_VALUE_FROM_UNSIGNED_INT(d, lo, hi, mode) \
 192   ereal_from_uint (&d, lo, hi, mode)
 193
 194 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs. */
 195 #if LONG_DOUBLE_TYPE_SIZE == 96
 196 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) (etarldouble ((IN), (OUT)))
 197 #else
 198 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) (etartdouble ((IN), (OUT)))
 199 #endif
 200 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) (etardouble ((IN), (OUT)))
 201
 202 /* IN is a REAL_VALUE_TYPE.  OUT is a long. */
 203 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) ((OUT) = etarsingle ((IN)))
 204
 205 /* Inverse of REAL_VALUE_TO_TARGET_DOUBLE. */
 206 #define REAL_VALUE_UNTO_TARGET_DOUBLE(d)  (ereal_unto_double (d))
 207
 208 /* Inverse of REAL_VALUE_TO_TARGET_SINGLE. */
 209 #define REAL_VALUE_UNTO_TARGET_SINGLE(f)  (ereal_unto_float (f))
 210
 211 /* d is an array of HOST_WIDE_INT that holds a double precision
 212    value in the target computer's floating point format. */
 213 #define REAL_VALUE_FROM_TARGET_DOUBLE(d)  (ereal_from_double (d))
 214
 215 /* f is a HOST_WIDE_INT containing a single precision target float value. */
 216 #define REAL_VALUE_FROM_TARGET_SINGLE(f)  (ereal_from_float (f))
 217
 218 /* Conversions to decimal ASCII string.  */
 219 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (ereal_to_decimal (r, s))
 220
 221 #endif /* REAL_ARITHMETIC defined */
 222
 223 /* **** End of software floating point emulator interface macros **** */
 224 #else /* No XFmode or TFmode and REAL_ARITHMETIC not defined */
 225
 226 /* old interface */
 227 #ifdef REAL_ARITHMETIC
 228 /* Defining REAL_IS_NOT_DOUBLE breaks certain initializations
 229    when REAL_ARITHMETIC etc. are not defined.  */
 230
 231 /* Now see if the host and target machines use the same format.
 232    If not, define REAL_IS_NOT_DOUBLE (even if we end up representing
 233    reals as doubles because we have no better way in this cross compiler.)
 234    This turns off various optimizations that can happen when we know the
 235    compiler's float format matches the target's float format.
 236    */
 237 #if HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
 238 #define REAL_IS_NOT_DOUBLE
 239 #ifndef REAL_VALUE_TYPE
 240 typedef struct {
 241     HOST_WIDE_INT r[sizeof (double)/sizeof (HOST_WIDE_INT)];
 242   } realvaluetype;
 243 #define REAL_VALUE_TYPE realvaluetype
 244 #endif /* no REAL_VALUE_TYPE */
 245 #endif /* formats differ */
 246 #endif /* 0 */
 247
 248 #endif /* emulator not used */
 249
 250 /* If we are not cross-compiling, use a `double' to represent the
 251    floating-point value.  Otherwise, use some other type
 252    (probably a struct containing an array of longs).  */
 253 #ifndef REAL_VALUE_TYPE
 254 #define REAL_VALUE_TYPE double
 255 #else
 256 #define REAL_IS_NOT_DOUBLE
 257 #endif
 258
 259 #if HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT
 260
 261 /* Convert a type `double' value in host format first to a type `float'
 262    value in host format and then to a single type `long' value which
 263    is the bitwise equivalent of the `float' value.  */
 264 #ifndef REAL_VALUE_TO_TARGET_SINGLE
 265 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT)                            \
 266 do { float f = (float) (IN);                                            \
 267      (OUT) = *(long *) &f;                                              \
 268    } while (0)
 269 #endif
 270
 271 /* Convert a type `double' value in host format to a pair of type `long'
 272    values which is its bitwise equivalent, but put the two words into
 273    proper word order for the target.  */
 274 #ifndef REAL_VALUE_TO_TARGET_DOUBLE
 275 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT)                            \
 276 do { REAL_VALUE_TYPE in = (IN);  /* Make sure it's not in a register.  */\
 277      if (HOST_FLOAT_WORDS_BIG_ENDIAN == FLOAT_WORDS_BIG_ENDIAN)         \
 278        {                                                                \
 279          (OUT)[0] = ((long *) &in)[0];                                  \
 280          (OUT)[1] = ((long *) &in)[1];                                  \
 281        }                                                                \
 282      else                                                               \
 283        {                                                                \
 284          (OUT)[1] = ((long *) &in)[0];                                  \
 285          (OUT)[0] = ((long *) &in)[1];                                  \
 286        }                                                                \
 287    } while (0)
 288 #endif
 289 #endif /* HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT */
 290
 291 /* In this configuration, double and long double are the same. */
 292 #ifndef REAL_VALUE_TO_TARGET_LONG_DOUBLE
 293 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(a, b) REAL_VALUE_TO_TARGET_DOUBLE (a, b)
 294 #endif
 295
 296 /* Compare two floating-point values for equality.  */
 297 #ifndef REAL_VALUES_EQUAL
 298 #define REAL_VALUES_EQUAL(x, y) ((x) == (y))
 299 #endif
 300
 301 /* Compare two floating-point values for less than.  */
 302 #ifndef REAL_VALUES_LESS
 303 #define REAL_VALUES_LESS(x, y) ((x) < (y))
 304 #endif
 305
 306 /* Truncate toward zero to an integer floating-point value.  */
 307 #ifndef REAL_VALUE_RNDZINT
 308 #define REAL_VALUE_RNDZINT(x) ((double) ((int) (x)))
 309 #endif
 310
 311 /* Truncate toward zero to an unsigned integer floating-point value.  */
 312 #ifndef REAL_VALUE_UNSIGNED_RNDZINT
 313 #define REAL_VALUE_UNSIGNED_RNDZINT(x) ((double) ((unsigned int) (x)))
 314 #endif
 315
 316 /* Convert a floating-point value to integer, rounding toward zero.  */
 317 #ifndef REAL_VALUE_FIX
 318 #define REAL_VALUE_FIX(x) ((int) (x))
 319 #endif
 320
 321 /* Convert a floating-point value to unsigned integer, rounding
 322    toward zero. */
 323 #ifndef REAL_VALUE_UNSIGNED_FIX
 324 #define REAL_VALUE_UNSIGNED_FIX(x) ((unsigned int) (x))
 325 #endif
 326
 327 /* Scale X by Y powers of 2.  */
 328 #ifndef REAL_VALUE_LDEXP
 329 #define REAL_VALUE_LDEXP(x, y) ldexp (x, y)
 330 extern double ldexp ();
 331 #endif
 332
 333 /* Convert the string X to a floating-point value.  */
 334 #ifndef REAL_VALUE_ATOF
 335 #if 1
 336 /* Use real.c to convert decimal numbers to binary, ... */
 337 REAL_VALUE_TYPE ereal_atof ();
 338 #define REAL_VALUE_ATOF(x, s) ereal_atof (x, s)
 339 #else
 340 /* ... or, if you like the host computer's atof, go ahead and use it: */
 341 #define REAL_VALUE_ATOF(x, s) atof (x)
 342 #if defined (MIPSEL) || defined (MIPSEB)
 343 /* MIPS compiler can't handle parens around the function name.
 344    This problem *does not* appear to be connected with any
 345    macro definition for atof.  It does not seem there is one.  */
 346 extern double atof ();
 347 #else
 348 extern double (atof) ();
 349 #endif
 350 #endif
 351 #endif
 352
 353 /* Negate the floating-point value X.  */
 354 #ifndef REAL_VALUE_NEGATE
 355 #define REAL_VALUE_NEGATE(x) (- (x))
 356 #endif
 357
 358 /* Truncate the floating-point value X to mode MODE.  This is correct only
 359    for the most common case where the host and target have objects of the same
 360    size and where `float' is SFmode.  */
 361
 362 /* Don't use REAL_VALUE_TRUNCATE directly--always call real_value_truncate.  */
 363 extern REAL_VALUE_TYPE real_value_truncate ();
 364
 365 #ifndef REAL_VALUE_TRUNCATE
 366 #define REAL_VALUE_TRUNCATE(mode, x) \
 367  (GET_MODE_BITSIZE (mode) == sizeof (float) * HOST_BITS_PER_CHAR        \
 368   ? (float) (x) : (x))
 369 #endif
 370
 371 /* Determine whether a floating-point value X is infinite. */
 372 #ifndef REAL_VALUE_ISINF
 373 #define REAL_VALUE_ISINF(x) (target_isinf (x))
 374 #endif
 375
 376 /* Determine whether a floating-point value X is a NaN. */
 377 #ifndef REAL_VALUE_ISNAN
 378 #define REAL_VALUE_ISNAN(x) (target_isnan (x))
 379 #endif
 380
 381 /* Determine whether a floating-point value X is negative. */
 382 #ifndef REAL_VALUE_NEGATIVE
 383 #define REAL_VALUE_NEGATIVE(x) (target_negative (x))
 384 #endif
 385
 386 /* Determine whether a floating-point value X is minus 0. */
 387 #ifndef REAL_VALUE_MINUS_ZERO
 388 #define REAL_VALUE_MINUS_ZERO(x) ((x) == 0 && REAL_VALUE_NEGATIVE (x))
 389 #endif
 390 \f
 391 /* Constant real values 0, 1, 2, and -1.  */
 392
 393 extern REAL_VALUE_TYPE dconst0;
 394 extern REAL_VALUE_TYPE dconst1;
 395 extern REAL_VALUE_TYPE dconst2;
 396 extern REAL_VALUE_TYPE dconstm1;
 397
 398 /* Union type used for extracting real values from CONST_DOUBLEs
 399    or putting them in.  */
 400
 401 union real_extract
 402 {
 403   REAL_VALUE_TYPE d;
 404   HOST_WIDE_INT i[sizeof (REAL_VALUE_TYPE) / sizeof (HOST_WIDE_INT)];
 405 };
 406
 407 /* For a CONST_DOUBLE:
 408    The usual two ints that hold the value.
 409    For a DImode, that is all there are;
 410     and CONST_DOUBLE_LOW is the low-order word and ..._HIGH the high-order.
 411    For a float, the number of ints varies,
 412     and CONST_DOUBLE_LOW is the one that should come first *in memory*.
 413     So use &CONST_DOUBLE_LOW(r) as the address of an array of ints.  */
 414 #define CONST_DOUBLE_LOW(r) XWINT (r, 2)
 415 #define CONST_DOUBLE_HIGH(r) XWINT (r, 3)
 416
 417 /* Link for chain of all CONST_DOUBLEs in use in current function.  */
 418 #define CONST_DOUBLE_CHAIN(r) XEXP (r, 1)
 419 /* The MEM which represents this CONST_DOUBLE's value in memory,
 420    or const0_rtx if no MEM has been made for it yet,
 421    or cc0_rtx if it is not on the chain.  */
 422 #define CONST_DOUBLE_MEM(r) XEXP (r, 0)
 423
 424 /* Function to return a real value (not a tree node)
 425    from a given integer constant.  */
 426 REAL_VALUE_TYPE real_value_from_int_cst ();
 427
 428 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents.  */
 429
 430 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from)          \
 431 do { union real_extract u;                              \
 432      bcopy ((char *) &CONST_DOUBLE_LOW ((from)), (char *) &u, sizeof u); \
 433      to = u.d; } while (0)
 434
 435 /* Return a CONST_DOUBLE with value R and mode M.  */
 436
 437 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) immed_real_const_1 (r,  m)
 438 extern struct rtx_def *immed_real_const_1       PROTO((REAL_VALUE_TYPE,
 439                                                        enum machine_mode));
 440
 441
 442 /* Convert a floating point value `r', that can be interpreted
 443    as a host machine float or double, to a decimal ASCII string `s'
 444    using printf format string `fmt'.  */
 445 #ifndef REAL_VALUE_TO_DECIMAL
 446 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (sprintf (s, fmt, r))
 447 #endif
 448
 449 /* Replace R by 1/R in the given machine mode, if the result is exact.  */
 450 extern int exact_real_inverse PROTO((enum machine_mode, REAL_VALUE_TYPE *));
 451
 452 #endif /* Not REAL_H_INCLUDED */