gcc/real.h

   1 /* Definitions of floating-point access for GNU compiler.
   2    Copyright (C) 1989, 1991, 1994, 1996, 1997, 1998,
   3    1999, 2000, 2002 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 FLOAT_WORDS_BIG_ENDIAN and HOST_FLOAT_WORDS_BIG_ENDIAN are not defined
  47    in the header files, then this implies the word-endianness is the same as
  48    for integers.  */
  49
  50 /* This is defined 0 or 1, like WORDS_BIG_ENDIAN.  */
  51 #ifndef FLOAT_WORDS_BIG_ENDIAN
  52 #define FLOAT_WORDS_BIG_ENDIAN WORDS_BIG_ENDIAN
  53 #endif
  54
  55 /* This is defined 0 or 1, unlike HOST_WORDS_BIG_ENDIAN.  */
  56 #ifndef HOST_FLOAT_WORDS_BIG_ENDIAN
  57 #ifdef HOST_WORDS_BIG_ENDIAN
  58 #define HOST_FLOAT_WORDS_BIG_ENDIAN 1
  59 #else
  60 #define HOST_FLOAT_WORDS_BIG_ENDIAN 0
  61 #endif
  62 #endif
  63
  64 #ifndef LONG_DOUBLE_TYPE_SIZE
  65 #define LONG_DOUBLE_TYPE_SIZE 64
  66 #endif
  67 /* MAX_LONG_DOUBLE_TYPE_SIZE is a constant tested by #if.
  68    LONG_DOUBLE_TYPE_SIZE can vary at compiler run time.
  69    So long as macros like REAL_VALUE_TO_TARGET_LONG_DOUBLE cannot
  70    vary too, however, then XFmode and TFmode long double
  71    cannot both be supported at the same time.  */
  72 #ifndef MAX_LONG_DOUBLE_TYPE_SIZE
  73 #define MAX_LONG_DOUBLE_TYPE_SIZE LONG_DOUBLE_TYPE_SIZE
  74 #endif
  75
  76 /* **** Start of software floating point emulator interface macros **** */
  77
  78 /* REAL_VALUE_TYPE is an array of the minimum number of HOST_WIDE_INTs
  79    required to hold MAX_LONG_DOUBLE_TYPE_SIZE bits.  */
  80 #if MAX_LONG_DOUBLE_TYPE_SIZE == 128
  81 /* For 128 bit reals, we calculate internally with extra precision.  */
  82 #define N (160 / BITS_PER_UNIT)
  83 #else
  84 #define N (MAX_LONG_DOUBLE_TYPE_SIZE / BITS_PER_UNIT)
  85 #endif
  86 #define S sizeof (HOST_WIDE_INT)
  87 typedef struct {
  88   HOST_WIDE_INT r[N/S + (N%S ? 1 : 0)]; /* round up */
  89 } REAL_VALUE_TYPE;
  90 #undef N
  91 #undef S
  92
  93 extern unsigned int significand_size    PARAMS ((enum machine_mode));
  94
  95 #define REAL_ARITHMETIC(value, code, d1, d2) \
  96   earith (&(value), (code), &(d1), &(d2))
  97
  98 /* Declare functions in real.c.  */
  99 extern void earith              PARAMS ((REAL_VALUE_TYPE *, int,
 100                                        REAL_VALUE_TYPE *, REAL_VALUE_TYPE *));
 101 extern REAL_VALUE_TYPE etrunci  PARAMS ((REAL_VALUE_TYPE));
 102 extern REAL_VALUE_TYPE etruncui PARAMS ((REAL_VALUE_TYPE));
 103 extern REAL_VALUE_TYPE ereal_negate PARAMS ((REAL_VALUE_TYPE));
 104 extern HOST_WIDE_INT efixi      PARAMS ((REAL_VALUE_TYPE));
 105 extern unsigned HOST_WIDE_INT efixui PARAMS ((REAL_VALUE_TYPE));
 106 extern void ereal_from_int      PARAMS ((REAL_VALUE_TYPE *,
 107                                        HOST_WIDE_INT, HOST_WIDE_INT,
 108                                        enum machine_mode));
 109 extern void ereal_from_uint     PARAMS ((REAL_VALUE_TYPE *,
 110                                        unsigned HOST_WIDE_INT,
 111                                        unsigned HOST_WIDE_INT,
 112                                        enum machine_mode));
 113 extern void ereal_to_int        PARAMS ((HOST_WIDE_INT *, HOST_WIDE_INT *,
 114                                        REAL_VALUE_TYPE));
 115 extern REAL_VALUE_TYPE ereal_ldexp PARAMS ((REAL_VALUE_TYPE, int));
 116
 117 extern void etartdouble         PARAMS ((REAL_VALUE_TYPE, long *));
 118 extern void etarldouble         PARAMS ((REAL_VALUE_TYPE, long *));
 119 extern void etardouble          PARAMS ((REAL_VALUE_TYPE, long *));
 120 extern long etarsingle          PARAMS ((REAL_VALUE_TYPE));
 121 extern void ereal_to_decimal    PARAMS ((REAL_VALUE_TYPE, char *));
 122 extern int ereal_cmp            PARAMS ((REAL_VALUE_TYPE, REAL_VALUE_TYPE));
 123 extern int ereal_isneg          PARAMS ((REAL_VALUE_TYPE));
 124 extern REAL_VALUE_TYPE ereal_unto_float PARAMS ((long));
 125 extern REAL_VALUE_TYPE ereal_unto_double PARAMS ((long *));
 126 extern REAL_VALUE_TYPE ereal_from_float PARAMS ((HOST_WIDE_INT));
 127 extern REAL_VALUE_TYPE ereal_from_double PARAMS ((HOST_WIDE_INT *));
 128
 129 #define REAL_VALUES_EQUAL(x, y) (ereal_cmp ((x), (y)) == 0)
 130 /* true if x < y : */
 131 #define REAL_VALUES_LESS(x, y) (ereal_cmp ((x), (y)) == -1)
 132 #define REAL_VALUE_LDEXP(x, n) ereal_ldexp (x, n)
 133
 134 /* Compare two floating-point objects for bitwise identity.
 135    This is not the same as comparing for equality on IEEE hosts:
 136    -0.0 equals 0.0 but they are not identical, and conversely
 137    two NaNs might be identical but they cannot be equal.  */
 138 #define REAL_VALUES_IDENTICAL(x, y) \
 139   (!memcmp ((char *) &(x), (char *) &(y), sizeof (REAL_VALUE_TYPE)))
 140
 141 /* These return REAL_VALUE_TYPE: */
 142 #define REAL_VALUE_RNDZINT(x) (etrunci (x))
 143 #define REAL_VALUE_UNSIGNED_RNDZINT(x) (etruncui (x))
 144
 145 /* Truncate the floating-point value X to mode MODE.  */
 146 #define REAL_VALUE_TRUNCATE(mode, x)  real_value_truncate (mode, x)
 147 extern REAL_VALUE_TYPE real_value_truncate PARAMS ((enum machine_mode,
 148                                                  REAL_VALUE_TYPE));
 149
 150 /* These return HOST_WIDE_INT: */
 151 /* Convert a floating-point value to integer, rounding toward zero.  */
 152 #define REAL_VALUE_FIX(x) (efixi (x))
 153 /* Convert a floating-point value to unsigned integer, rounding
 154    toward zero.  */
 155 #define REAL_VALUE_UNSIGNED_FIX(x) (efixui (x))
 156
 157 /* Convert ASCII string S to floating point in mode M.
 158    Decimal input uses ATOF.  Hexadecimal uses HTOF.  */
 159 #define REAL_VALUE_ATOF(s,m) ereal_atof(s,m)
 160 #define REAL_VALUE_HTOF(s,m) ereal_atof(s,m)
 161
 162 #define REAL_VALUE_NEGATE ereal_negate
 163
 164 /* Determine whether a floating-point value X is infinite.  */
 165 #define REAL_VALUE_ISINF(x) (target_isinf (x))
 166
 167 /* Determine whether a floating-point value X is a NaN.  */
 168 #define REAL_VALUE_ISNAN(x) (target_isnan (x))
 169
 170 /* Determine whether a floating-point value X is negative.  */
 171 #define REAL_VALUE_NEGATIVE(x) (target_negative (x))
 172
 173 /* Determine whether a floating-point value X is minus zero.  */
 174 #define REAL_VALUE_MINUS_ZERO(x) \
 175  ((ereal_cmp (x, dconst0) == 0) && (ereal_isneg (x) != 0 ))
 176
 177 #define REAL_VALUE_TO_INT ereal_to_int
 178
 179 /* Here the cast to HOST_WIDE_INT sign-extends arguments such as ~0.  */
 180 #define REAL_VALUE_FROM_INT(d, lo, hi, mode) \
 181   ereal_from_int (&d, (HOST_WIDE_INT) (lo), (HOST_WIDE_INT) (hi), mode)
 182
 183 #define REAL_VALUE_FROM_UNSIGNED_INT(d, lo, hi, mode) \
 184   ereal_from_uint (&d, lo, hi, mode)
 185
 186 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 187 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)               \
 188    (LONG_DOUBLE_TYPE_SIZE == 64 ? etardouble ((IN), (OUT))      \
 189     : LONG_DOUBLE_TYPE_SIZE == 96 ? etarldouble ((IN), (OUT))   \
 190     : LONG_DOUBLE_TYPE_SIZE == 128 ? etartdouble ((IN), (OUT))  \
 191     : abort ())
 192 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) (etardouble ((IN), (OUT)))
 193
 194 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 195 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) ((OUT) = etarsingle ((IN)))
 196
 197 /* Inverse of REAL_VALUE_TO_TARGET_DOUBLE.  */
 198 #define REAL_VALUE_UNTO_TARGET_DOUBLE(d)  (ereal_unto_double (d))
 199
 200 /* Inverse of REAL_VALUE_TO_TARGET_SINGLE.  */
 201 #define REAL_VALUE_UNTO_TARGET_SINGLE(f)  (ereal_unto_float (f))
 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 /* **** End of software floating point emulator interface macros **** */
 214 \f
 215 /* Constant real values 0, 1, 2, and -1.  */
 216
 217 extern REAL_VALUE_TYPE dconst0;
 218 extern REAL_VALUE_TYPE dconst1;
 219 extern REAL_VALUE_TYPE dconst2;
 220 extern REAL_VALUE_TYPE dconstm1;
 221
 222 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents.  */
 223 /* Function to return a real value (not a tree node)
 224    from a given integer constant.  */
 225 union tree_node;
 226 REAL_VALUE_TYPE real_value_from_int_cst PARAMS ((union tree_node *,
 227                                                 union tree_node *));
 228
 229 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from)          \
 230   memcpy (&(to), &CONST_DOUBLE_LOW ((from)), sizeof (REAL_VALUE_TYPE))
 231
 232 /* Return a CONST_DOUBLE with value R and mode M.  */
 233
 234 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) immed_real_const_1 (r,  m)
 235 extern struct rtx_def *immed_real_const_1       PARAMS ((REAL_VALUE_TYPE,
 236                                                        enum machine_mode));
 237
 238 /* Replace R by 1/R in the given machine mode, if the result is exact.  */
 239 extern int exact_real_inverse   PARAMS ((enum machine_mode, REAL_VALUE_TYPE *));
 240 extern int target_isnan         PARAMS ((REAL_VALUE_TYPE));
 241 extern int target_isinf         PARAMS ((REAL_VALUE_TYPE));
 242 extern int target_negative      PARAMS ((REAL_VALUE_TYPE));
 243 extern void debug_real          PARAMS ((REAL_VALUE_TYPE));
 244 extern REAL_VALUE_TYPE ereal_atof PARAMS ((const char *, enum machine_mode));
 245
 246 #endif /* ! GCC_REAL_H */