gcc/real.h

   1 /* Front-end tree definitions for GNU compiler.
   2    Copyright (C) 1989, 1991, 1994 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, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #ifndef REAL_H_INCLUDED
  21 #define REAL_H_INCLUDED
  22
  23 /* Define codes for all the float formats that we know of.  */
  24 #define UNKNOWN_FLOAT_FORMAT 0
  25 #define IEEE_FLOAT_FORMAT 1
  26 #define VAX_FLOAT_FORMAT 2
  27 #define IBM_FLOAT_FORMAT 3
  28
  29 /* Default to IEEE float if not specified.  Nearly all machines use it.  */
  30
  31 #ifndef TARGET_FLOAT_FORMAT
  32 #define TARGET_FLOAT_FORMAT     IEEE_FLOAT_FORMAT
  33 #endif
  34
  35 #ifndef HOST_FLOAT_FORMAT
  36 #define HOST_FLOAT_FORMAT       IEEE_FLOAT_FORMAT
  37 #endif
  38
  39 #if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
  40 #define REAL_INFINITY
  41 #endif
  42
  43 /* If FLOAT_WORDS_BIG_ENDIAN and HOST_FLOAT_WORDS_BIG_ENDIAN are not defined
  44    in the header files, then this implies the word-endianness is the same as
  45    for integers.  */
  46
  47 /* This is defined 0 or 1, like WORDS_BIG_ENDIAN.  */
  48 #ifndef FLOAT_WORDS_BIG_ENDIAN
  49 #define FLOAT_WORDS_BIG_ENDIAN WORDS_BIG_ENDIAN
  50 #endif
  51
  52 /* This is defined 0 or 1, unlike HOST_WORDS_BIG_ENDIAN.  */
  53 #ifndef HOST_FLOAT_WORDS_BIG_ENDIAN
  54 #ifdef HOST_WORDS_BIG_ENDIAN
  55 #define HOST_FLOAT_WORDS_BIG_ENDIAN 1
  56 #else
  57 #define HOST_FLOAT_WORDS_BIG_ENDIAN 0
  58 #endif
  59 #endif
  60
  61 /* Defining REAL_ARITHMETIC invokes a floating point emulator
  62    that can produce a target machine format differing by more
  63    than just endian-ness from the host's format.  The emulator
  64    is also used to support extended real XFmode.  */
  65 #ifndef LONG_DOUBLE_TYPE_SIZE
  66 #define LONG_DOUBLE_TYPE_SIZE 64
  67 #endif
  68 #if (LONG_DOUBLE_TYPE_SIZE == 96) || (LONG_DOUBLE_TYPE_SIZE == 128)
  69 #ifndef REAL_ARITHMETIC
  70 #define REAL_ARITHMETIC
  71 #endif
  72 #endif
  73 #ifdef REAL_ARITHMETIC
  74 /* **** Start of software floating point emulator interface macros **** */
  75
  76 /* Support 80-bit extended real XFmode if LONG_DOUBLE_TYPE_SIZE
  77    has been defined to be 96 in the tm.h machine file. */
  78 #if (LONG_DOUBLE_TYPE_SIZE == 96)
  79 #define REAL_IS_NOT_DOUBLE
  80 #define REAL_ARITHMETIC
  81 typedef struct {
  82   HOST_WIDE_INT r[(11 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
  83 } realvaluetype;
  84 #define REAL_VALUE_TYPE realvaluetype
  85
  86 #else /* no XFmode support */
  87
  88 #if (LONG_DOUBLE_TYPE_SIZE == 128)
  89
  90 #define REAL_IS_NOT_DOUBLE
  91 #define REAL_ARITHMETIC
  92 typedef struct {
  93   HOST_WIDE_INT r[(19 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
  94 } realvaluetype;
  95 #define REAL_VALUE_TYPE realvaluetype
  96
  97 #else /* not TFmode */
  98
  99 #if HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
 100 /* If no XFmode support, then a REAL_VALUE_TYPE is 64 bits wide
 101    but it is not necessarily a host machine double. */
 102 #define REAL_IS_NOT_DOUBLE
 103 typedef struct {
 104   HOST_WIDE_INT r[(7 + sizeof (HOST_WIDE_INT))/(sizeof (HOST_WIDE_INT))];
 105 } realvaluetype;
 106 #define REAL_VALUE_TYPE realvaluetype
 107 #else
 108 /* If host and target formats are compatible, then a REAL_VALUE_TYPE
 109    is actually a host machine double. */
 110 #define REAL_VALUE_TYPE double
 111 #endif
 112
 113 #endif /* no TFmode support */
 114 #endif /* no XFmode support */
 115
 116 extern int significand_size     PROTO((enum machine_mode));
 117
 118 /* If emulation has been enabled by defining REAL_ARITHMETIC or by
 119    setting LONG_DOUBLE_TYPE_SIZE to 96 or 128, then define macros so that
 120    they invoke emulator functions. This will succeed only if the machine
 121    files have been updated to use these macros in place of any
 122    references to host machine `double' or `float' types.  */
 123 #ifdef REAL_ARITHMETIC
 124 #undef REAL_ARITHMETIC
 125 #define REAL_ARITHMETIC(value, code, d1, d2) \
 126   earith (&(value), (code), &(d1), &(d2))
 127
 128 /* Declare functions in real.c. */
 129 extern void earith              PROTO((REAL_VALUE_TYPE *, int,
 130                                        REAL_VALUE_TYPE *, REAL_VALUE_TYPE *));
 131 extern REAL_VALUE_TYPE etrunci  PROTO((REAL_VALUE_TYPE));
 132 extern REAL_VALUE_TYPE etruncui PROTO((REAL_VALUE_TYPE));
 133 extern REAL_VALUE_TYPE ereal_atof PROTO((char *, enum machine_mode));
 134 extern REAL_VALUE_TYPE ereal_negate PROTO((REAL_VALUE_TYPE));
 135 extern HOST_WIDE_INT efixi      PROTO((REAL_VALUE_TYPE));
 136 extern unsigned HOST_WIDE_INT efixui PROTO((REAL_VALUE_TYPE));
 137 extern void ereal_from_int      PROTO((REAL_VALUE_TYPE *,
 138                                        HOST_WIDE_INT, HOST_WIDE_INT));
 139 extern void ereal_from_uint     PROTO((REAL_VALUE_TYPE *,
 140                                        unsigned HOST_WIDE_INT,
 141                                        unsigned HOST_WIDE_INT));
 142 extern void ereal_to_int        PROTO((HOST_WIDE_INT *, HOST_WIDE_INT *,
 143                                        REAL_VALUE_TYPE));
 144 extern REAL_VALUE_TYPE ereal_ldexp PROTO((REAL_VALUE_TYPE, int));
 145
 146 extern void etartdouble         PROTO((REAL_VALUE_TYPE, long *));
 147 extern void etarldouble         PROTO((REAL_VALUE_TYPE, long *));
 148 extern void etardouble          PROTO((REAL_VALUE_TYPE, long *));
 149 extern long etarsingle          PROTO((REAL_VALUE_TYPE));
 150 extern void ereal_to_decimal    PROTO((REAL_VALUE_TYPE, char *));
 151 extern int ereal_cmp            PROTO((REAL_VALUE_TYPE, REAL_VALUE_TYPE));
 152 extern int ereal_isneg          PROTO((REAL_VALUE_TYPE));
 153 extern REAL_VALUE_TYPE ereal_from_float PROTO((HOST_WIDE_INT));
 154 extern REAL_VALUE_TYPE ereal_from_double PROTO((HOST_WIDE_INT *));
 155
 156 #define REAL_VALUES_EQUAL(x, y) (ereal_cmp ((x), (y)) == 0)
 157 /* true if x < y : */
 158 #define REAL_VALUES_LESS(x, y) (ereal_cmp ((x), (y)) == -1)
 159 #define REAL_VALUE_LDEXP(x, n) ereal_ldexp (x, n)
 160
 161 /* These return REAL_VALUE_TYPE: */
 162 #define REAL_VALUE_RNDZINT(x) (etrunci (x))
 163 #define REAL_VALUE_UNSIGNED_RNDZINT(x) (etruncui (x))
 164 extern REAL_VALUE_TYPE real_value_truncate ();
 165 #define REAL_VALUE_TRUNCATE(mode, x)  real_value_truncate (mode, x)
 166
 167 /* These return HOST_WIDE_INT: */
 168 /* Convert a floating-point value to integer, rounding toward zero.  */
 169 #define REAL_VALUE_FIX(x) (efixi (x))
 170 /* Convert a floating-point value to unsigned integer, rounding
 171    toward zero. */
 172 #define REAL_VALUE_UNSIGNED_FIX(x) (efixui (x))
 173
 174 #define REAL_VALUE_ATOF ereal_atof
 175 #define REAL_VALUE_NEGATE ereal_negate
 176
 177 #define REAL_VALUE_MINUS_ZERO(x) \
 178  ((ereal_cmp (x, dconst0) == 0) && (ereal_isneg (x) != 0 ))
 179
 180 #define REAL_VALUE_TO_INT ereal_to_int
 181
 182 /* Here the cast to HOST_WIDE_INT sign-extends arguments such as ~0.  */
 183 #define REAL_VALUE_FROM_INT(d, lo, hi) \
 184   ereal_from_int (&d, (HOST_WIDE_INT) (lo), (HOST_WIDE_INT) (hi))
 185
 186 #define REAL_VALUE_FROM_UNSIGNED_INT(d, lo, hi) (ereal_from_uint (&d, lo, hi))
 187
 188 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs. */
 189 #if LONG_DOUBLE_TYPE_SIZE == 96
 190 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) (etarldouble ((IN), (OUT)))
 191 #else
 192 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) (etartdouble ((IN), (OUT)))
 193 #endif
 194 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) (etardouble ((IN), (OUT)))
 195
 196 /* IN is a REAL_VALUE_TYPE.  OUT is a long. */
 197 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) ((OUT) = etarsingle ((IN)))
 198
 199 /* d is an array of HOST_WIDE_INT that holds a double precision
 200    value in the target computer's floating point format. */
 201 #define REAL_VALUE_FROM_TARGET_DOUBLE(d)  (ereal_from_double (d))
 202
 203 /* f is a HOST_WIDE_INT containing a single precision target float value. */
 204 #define REAL_VALUE_FROM_TARGET_SINGLE(f)  (ereal_from_float (f))
 205
 206 /* Conversions to decimal ASCII string.  */
 207 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (ereal_to_decimal (r, s))
 208
 209 #endif /* REAL_ARITHMETIC defined */
 210
 211 /* **** End of software floating point emulator interface macros **** */
 212 #else /* No XFmode or TFmode and REAL_ARITHMETIC not defined */
 213
 214 /* old interface */
 215 #ifdef REAL_ARITHMETIC
 216 /* Defining REAL_IS_NOT_DOUBLE breaks certain initializations
 217    when REAL_ARITHMETIC etc. are not defined.  */
 218
 219 /* Now see if the host and target machines use the same format.
 220    If not, define REAL_IS_NOT_DOUBLE (even if we end up representing
 221    reals as doubles because we have no better way in this cross compiler.)
 222    This turns off various optimizations that can happen when we know the
 223    compiler's float format matches the target's float format.
 224    */
 225 #if HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
 226 #define REAL_IS_NOT_DOUBLE
 227 #ifndef REAL_VALUE_TYPE
 228 typedef struct {
 229     HOST_WIDE_INT r[sizeof (double)/sizeof (HOST_WIDE_INT)];
 230   } realvaluetype;
 231 #define REAL_VALUE_TYPE realvaluetype
 232 #endif /* no REAL_VALUE_TYPE */
 233 #endif /* formats differ */
 234 #endif /* 0 */
 235
 236 #endif /* emulator not used */
 237
 238 /* If we are not cross-compiling, use a `double' to represent the
 239    floating-point value.  Otherwise, use some other type
 240    (probably a struct containing an array of longs).  */
 241 #ifndef REAL_VALUE_TYPE
 242 #define REAL_VALUE_TYPE double
 243 #else
 244 #define REAL_IS_NOT_DOUBLE
 245 #endif
 246
 247 #if HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT
 248
 249 /* Convert a type `double' value in host format first to a type `float'
 250    value in host format and then to a single type `long' value which
 251    is the bitwise equivalent of the `float' value.  */
 252 #ifndef REAL_VALUE_TO_TARGET_SINGLE
 253 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT)                            \
 254 do { float f = (float) (IN);                                            \
 255      (OUT) = *(long *) &f;                                              \
 256    } while (0)
 257 #endif
 258
 259 /* Convert a type `double' value in host format to a pair of type `long'
 260    values which is its bitwise equivalent, but put the two words into
 261    proper word order for the target.  */
 262 #ifndef REAL_VALUE_TO_TARGET_DOUBLE
 263 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT)                            \
 264 do { REAL_VALUE_TYPE in = (IN);  /* Make sure it's not in a register.  */\
 265      if (HOST_FLOAT_WORDS_BIG_ENDIAN == FLOAT_WORDS_BIG_ENDIAN)         \
 266        {                                                                \
 267          (OUT)[0] = ((long *) &in)[0];                                  \
 268          (OUT)[1] = ((long *) &in)[1];                                  \
 269        }                                                                \
 270      else                                                               \
 271        {                                                                \
 272          (OUT)[1] = ((long *) &in)[0];                                  \
 273          (OUT)[0] = ((long *) &in)[1];                                  \
 274        }                                                                \
 275    } while (0)
 276 #endif
 277 #endif /* HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT */
 278
 279 /* In this configuration, double and long double are the same. */
 280 #ifndef REAL_VALUE_TO_TARGET_LONG_DOUBLE
 281 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(a, b) REAL_VALUE_TO_TARGET_DOUBLE (a, b)
 282 #endif
 283
 284 /* Compare two floating-point values for equality.  */
 285 #ifndef REAL_VALUES_EQUAL
 286 #define REAL_VALUES_EQUAL(x, y) ((x) == (y))
 287 #endif
 288
 289 /* Compare two floating-point values for less than.  */
 290 #ifndef REAL_VALUES_LESS
 291 #define REAL_VALUES_LESS(x, y) ((x) < (y))
 292 #endif
 293
 294 /* Truncate toward zero to an integer floating-point value.  */
 295 #ifndef REAL_VALUE_RNDZINT
 296 #define REAL_VALUE_RNDZINT(x) ((double) ((int) (x)))
 297 #endif
 298
 299 /* Truncate toward zero to an unsigned integer floating-point value.  */
 300 #ifndef REAL_VALUE_UNSIGNED_RNDZINT
 301 #define REAL_VALUE_UNSIGNED_RNDZINT(x) ((double) ((unsigned int) (x)))
 302 #endif
 303
 304 /* Convert a floating-point value to integer, rounding toward zero.  */
 305 #ifndef REAL_VALUE_FIX
 306 #define REAL_VALUE_FIX(x) ((int) (x))
 307 #endif
 308
 309 /* Convert a floating-point value to unsigned integer, rounding
 310    toward zero. */
 311 #ifndef REAL_VALUE_UNSIGNED_FIX
 312 #define REAL_VALUE_UNSIGNED_FIX(x) ((unsigned int) (x))
 313 #endif
 314
 315 /* Scale X by Y powers of 2.  */
 316 #ifndef REAL_VALUE_LDEXP
 317 #define REAL_VALUE_LDEXP(x, y) ldexp (x, y)
 318 extern double ldexp ();
 319 #endif
 320
 321 /* Convert the string X to a floating-point value.  */
 322 #ifndef REAL_VALUE_ATOF
 323 #if 1
 324 /* Use real.c to convert decimal numbers to binary, ... */
 325 REAL_VALUE_TYPE ereal_atof ();
 326 #define REAL_VALUE_ATOF(x, s) ereal_atof (x, s)
 327 #else
 328 /* ... or, if you like the host computer's atof, go ahead and use it: */
 329 #define REAL_VALUE_ATOF(x, s) atof (x)
 330 #if defined (MIPSEL) || defined (MIPSEB)
 331 /* MIPS compiler can't handle parens around the function name.
 332    This problem *does not* appear to be connected with any
 333    macro definition for atof.  It does not seem there is one.  */
 334 extern double atof ();
 335 #else
 336 extern double (atof) ();
 337 #endif
 338 #endif
 339 #endif
 340
 341 /* Negate the floating-point value X.  */
 342 #ifndef REAL_VALUE_NEGATE
 343 #define REAL_VALUE_NEGATE(x) (- (x))
 344 #endif
 345
 346 /* Truncate the floating-point value X to mode MODE.  This is correct only
 347    for the most common case where the host and target have objects of the same
 348    size and where `float' is SFmode.  */
 349
 350 /* Don't use REAL_VALUE_TRUNCATE directly--always call real_value_truncate.  */
 351 extern REAL_VALUE_TYPE real_value_truncate ();
 352
 353 #ifndef REAL_VALUE_TRUNCATE
 354 #define REAL_VALUE_TRUNCATE(mode, x) \
 355  (GET_MODE_BITSIZE (mode) == sizeof (float) * HOST_BITS_PER_CHAR        \
 356   ? (float) (x) : (x))
 357 #endif
 358
 359 /* Determine whether a floating-point value X is infinite. */
 360 #ifndef REAL_VALUE_ISINF
 361 #define REAL_VALUE_ISINF(x) (target_isinf (x))
 362 #endif
 363
 364 /* Determine whether a floating-point value X is a NaN. */
 365 #ifndef REAL_VALUE_ISNAN
 366 #define REAL_VALUE_ISNAN(x) (target_isnan (x))
 367 #endif
 368
 369 /* Determine whether a floating-point value X is negative. */
 370 #ifndef REAL_VALUE_NEGATIVE
 371 #define REAL_VALUE_NEGATIVE(x) (target_negative (x))
 372 #endif
 373
 374 /* Determine whether a floating-point value X is minus 0. */
 375 #ifndef REAL_VALUE_MINUS_ZERO
 376 #define REAL_VALUE_MINUS_ZERO(x) ((x) == 0 && REAL_VALUE_NEGATIVE (x))
 377 #endif
 378 \f
 379 /* Constant real values 0, 1, 2, and -1.  */
 380
 381 extern REAL_VALUE_TYPE dconst0;
 382 extern REAL_VALUE_TYPE dconst1;
 383 extern REAL_VALUE_TYPE dconst2;
 384 extern REAL_VALUE_TYPE dconstm1;
 385
 386 /* Union type used for extracting real values from CONST_DOUBLEs
 387    or putting them in.  */
 388
 389 union real_extract
 390 {
 391   REAL_VALUE_TYPE d;
 392   HOST_WIDE_INT i[sizeof (REAL_VALUE_TYPE) / sizeof (HOST_WIDE_INT)];
 393 };
 394
 395 /* For a CONST_DOUBLE:
 396    The usual two ints that hold the value.
 397    For a DImode, that is all there are;
 398     and CONST_DOUBLE_LOW is the low-order word and ..._HIGH the high-order.
 399    For a float, the number of ints varies,
 400     and CONST_DOUBLE_LOW is the one that should come first *in memory*.
 401     So use &CONST_DOUBLE_LOW(r) as the address of an array of ints.  */
 402 #define CONST_DOUBLE_LOW(r) XWINT (r, 2)
 403 #define CONST_DOUBLE_HIGH(r) XWINT (r, 3)
 404
 405 /* Link for chain of all CONST_DOUBLEs in use in current function.  */
 406 #define CONST_DOUBLE_CHAIN(r) XEXP (r, 1)
 407 /* The MEM which represents this CONST_DOUBLE's value in memory,
 408    or const0_rtx if no MEM has been made for it yet,
 409    or cc0_rtx if it is not on the chain.  */
 410 #define CONST_DOUBLE_MEM(r) XEXP (r, 0)
 411
 412 /* Function to return a real value (not a tree node)
 413    from a given integer constant.  */
 414 REAL_VALUE_TYPE real_value_from_int_cst ();
 415
 416 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents.  */
 417
 418 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from)          \
 419 do { union real_extract u;                              \
 420      bcopy ((char *) &CONST_DOUBLE_LOW ((from)), (char *) &u, sizeof u); \
 421      to = u.d; } while (0)
 422
 423 /* Return a CONST_DOUBLE with value R and mode M.  */
 424
 425 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) immed_real_const_1 (r,  m)
 426 extern struct rtx_def *immed_real_const_1       PROTO((REAL_VALUE_TYPE,
 427                                                        enum machine_mode));
 428
 429
 430 /* Convert a floating point value `r', that can be interpreted
 431    as a host machine float or double, to a decimal ASCII string `s'
 432    using printf format string `fmt'.  */
 433 #ifndef REAL_VALUE_TO_DECIMAL
 434 #define REAL_VALUE_TO_DECIMAL(r, fmt, s) (sprintf (s, fmt, r))
 435 #endif
 436
 437 #endif /* Not REAL_H_INCLUDED */