gcc/ginclude/float.h

   1 /* Copyright (C) 2002 Free Software Foundation, Inc.
   2
   3 This file is part of GCC.
   4
   5 GCC is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2, or (at your option)
   8 any later version.
   9
  10 GCC is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with GCC; see the file COPYING.  If not, write to
  17 the Free Software Foundation, 59 Temple Place - Suite 330,
  18 Boston, MA 02111-1307, USA.  */
  19
  20 /* As a special exception, if you include this header file into source
  21    files compiled by GCC, this header file does not by itself cause
  22    the resulting executable to be covered by the GNU General Public
  23    License.  This exception does not however invalidate any other
  24    reasons why the executable file might be covered by the GNU General
  25    Public License.  */
  26
  27 /*
  28  * ISO C Standard:  5.2.4.2.2  Characteristics of floating types <float.h>
  29  */
  30
  31 #ifndef _FLOAT_H___
  32 #define _FLOAT_H___
  33
  34 /* Radix of exponent representation, b. */
  35 #undef FLT_RADIX
  36 #define FLT_RADIX       __FLT_RADIX__
  37
  38 /* Number of base-FLT_RADIX digits in the significand, p.  */
  39 #undef FLT_MANT_DIG
  40 #undef DBL_MANT_DIG
  41 #undef LDBL_MANT_DIG
  42 #define FLT_MANT_DIG    __FLT_MANT_DIG__
  43 #define DBL_MANT_DIG    __DBL_MANT_DIG__
  44 #define LDBL_MANT_DIG   __LDBL_MANT_DIG__
  45
  46 /* Number of decimal digits, q, such that any floating-point number with q
  47    decimal digits can be rounded into a floating-point number with p radix b
  48    digits and back again without change to the q decimal digits,
  49
  50         p * log10(b)                    if b is a power of 10
  51         floor((p - 1) * log10(b))       otherwise
  52 */
  53 #undef FLT_DIG
  54 #undef DBL_DIG
  55 #undef LDBL_DIG
  56 #define FLT_DIG         __FLT_DIG__
  57 #define DBL_DIG         __DBL_DIG__
  58 #define LDBL_DIG        __LDBL_DIG__
  59
  60 /* Minimum int x such that FLT_RADIX**(x-1) is a normalized float, emin */
  61 #undef FLT_MIN_EXP
  62 #undef DBL_MIN_EXP
  63 #undef LDBL_MIN_EXP
  64 #define FLT_MIN_EXP     __FLT_MIN_EXP__
  65 #define DBL_MIN_EXP     __DBL_MIN_EXP__
  66 #define LDBL_MIN_EXP    __LDBL_MIN_EXP__
  67
  68 /* Minimum negative integer such that 10 raised to that power is in the
  69    range of normalized floating-point numbers,
  70
  71         ceil(log10(b) * (emin - 1))
  72 */
  73 #undef FLT_MIN_10_EXP
  74 #undef DBL_MIN_10_EXP
  75 #undef LDBL_MIN_10_EXP
  76 #define FLT_MIN_10_EXP  __FLT_MIN_10_EXP__
  77 #define DBL_MIN_10_EXP  __DBL_MIN_10_EXP__
  78 #define LDBL_MIN_10_EXP __LDBL_MIN_10_EXP__
  79
  80 /* Maximum int x such that FLT_RADIX**(x-1) is a representable float, emax.  */
  81 #undef FLT_MAX_EXP
  82 #undef DBL_MAX_EXP
  83 #undef LDBL_MAX_EXP
  84 #define FLT_MAX_EXP     __FLT_MAX_EXP__
  85 #define DBL_MAX_EXP     __DBL_MAX_EXP__
  86 #define LDBL_MAX_EXP    __LDBL_MAX_EXP__
  87
  88 /* Maximum integer such that 10 raised to that power is in the range of
  89    representable finite floating-point numbers,
  90
  91         floor(log10((1 - b**-p) * b**emax))
  92 */
  93 #undef FLT_MAX_10_EXP
  94 #undef DBL_MAX_10_EXP
  95 #undef LDBL_MAX_10_EXP
  96 #define FLT_MAX_10_EXP  __FLT_MAX_10_EXP__
  97 #define DBL_MAX_10_EXP  __DBL_MAX_10_EXP__
  98 #define LDBL_MAX_10_EXP __LDBL_MAX_10_EXP__
  99
 100 /* Maximum representable finite floating-point number,
 101
 102         (1 - b**-p) * b**emax
 103 */
 104 #undef FLT_MAX
 105 #undef DBL_MAX
 106 #undef LDBL_MAX
 107 #define FLT_MAX         __FLT_MAX__
 108 #define DBL_MAX         __DBL_MAX__
 109 #define LDBL_MAX        __LDBL_MAX__
 110
 111 /* The difference between 1 and the least value greater than 1 that is
 112    representable in the given floating point type, b**1-p.  */
 113 #undef FLT_EPSILON
 114 #undef DBL_EPSILON
 115 #undef LDBL_EPSILON
 116 #define FLT_EPSILON     __FLT_EPSILON__
 117 #define DBL_EPSILON     __DBL_EPSILON__
 118 #define LDBL_EPSILON    __LDBL_EPSILON__
 119
 120 /* Minimum normalized positive floating-point number, b**(emin - 1).  */
 121 #undef FLT_MIN
 122 #undef DBL_MIN
 123 #undef LDBL_MIN
 124 #define FLT_MIN         __FLT_MIN__
 125 #define DBL_MIN         __DBL_MIN__
 126 #define LDBL_MIN        __LDBL_MIN__
 127
 128 /* Addition rounds to 0: zero, 1: nearest, 2: +inf, 3: -inf, -1: unknown.  */
 129 /* ??? This is supposed to change with calls to fesetround in <fenv.h>.  */
 130 #undef FLT_ROUNDS
 131 #define FLT_ROUNDS 1
 132
 133 #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
 134 /* The floating-point expression evaluation method.
 135         -1  indeterminate
 136          0  evaluate all operations and constants just to the range and
 137             precision of the type
 138          1  evaluate operations and constants of type float and double
 139             to the range and precision of the double type, evaluate
 140             long double operations and constants to the range and
 141             precision of the long double type
 142          2  evaluate all operations and constants to the range and
 143             precision of the long double type
 144
 145    ??? This ought to change with the setting of the fp control word;
 146    the value provided by the compiler assumes the widest setting.  */
 147 #undef FLT_EVAL_METHOD
 148 #define FLT_EVAL_METHOD __FLT_EVAL_METHOD__
 149
 150 /* Number of decimal digits, n, such that any floating-point number in the
 151    widest supported floating type with pmax radix b digits can be rounded
 152    to a floating-point number with n decimal digits and back again without
 153    change to the value,
 154
 155         pmax * log10(b)                 if b is a power of 10
 156         ceil(1 + pmax * log10(b))       otherwise
 157 */
 158 #undef DECIMAL_DIG
 159 #define DECIMAL_DIG     __DECIMAL_DIG__
 160
 161 #endif /* C99 */
 162 #endif /* _FLOAT_H___ */