sysdeps/sh/bits/huge_val.h

   1 /* `HUGE_VAL' constants for IEEE 754 machines (where it is infinity).
   2    Used by <stdlib.h> and <math.h> functions for overflow.
   3    SH version.
   4    Copyright (C) 1992, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
   5    This file is part of the GNU C Library.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #ifndef _MATH_H
  23 # error "Never use <bits/huge_val.h> directly; include <math.h> instead."
  24 #endif
  25
  26 #include <features.h>
  27
  28 /* IEEE positive infinity (-HUGE_VAL is negative infinity).  */
  29
  30 #ifdef  __GNUC__
  31
  32 # if __GNUC_PREREQ(2,96)
  33
  34 #  define HUGE_VAL (__extension__ 0x1.0p2047)
  35
  36 # else
  37
  38 #  define HUGE_VAL \
  39   (__extension__                                                              \
  40    ((union { unsigned __l __attribute__((__mode__(__DI__))); double __d; })   \
  41     { __l: 0x000000007ff00000ULL }).__d)
  42
  43 # endif
  44
  45 #else /* not GCC */
  46
  47 # include <endian.h>
  48
  49 typedef union { unsigned char __c[8]; double __d; } __huge_val_t;
  50
  51 # if __BYTE_ORDER == __BIG_ENDIAN
  52 #  define __HUGE_VAL_bytes      { 0, 0, 0, 0, 0x7f, 0xf0, 0, 0 }
  53 # endif
  54 # if __BYTE_ORDER == __LITTLE_ENDIAN
  55 #  define __HUGE_VAL_bytes      { 0, 0, 0xf0, 0x7f, 0, 0, 0, 0 }
  56 # endif
  57
  58 static __huge_val_t __huge_val = { __HUGE_VAL_bytes };
  59 # define HUGE_VAL       (__huge_val.__d)
  60
  61 #endif  /* GCC.  */
  62
  63
  64 /* ISO C99 extensions: (float) HUGE_VALF and (long double) HUGE_VALL.  */
  65
  66 #ifdef __USE_ISOC99
  67
  68 # ifdef __GNUC__
  69
  70 #  if __GNUC_PREREQ(2,96)
  71
  72 #   define HUGE_VALF (__extension__ 0x1.0p255f)
  73
  74 #  else
  75
  76 #   define HUGE_VALF \
  77   (__extension__                                                              \
  78    ((union { unsigned __l __attribute__((__mode__(__SI__))); float __d; })    \
  79     { __l: 0x7f800000UL }).__d)
  80
  81 #  endif
  82
  83 # else /* not GCC */
  84
  85 typedef union { unsigned char __c[4]; float __f; } __huge_valf_t;
  86
  87 #  if __BYTE_ORDER == __BIG_ENDIAN
  88 #   define __HUGE_VALF_bytes    { 0x7f, 0x80, 0, 0 }
  89 #  endif
  90 #  if __BYTE_ORDER == __LITTLE_ENDIAN
  91 #   define __HUGE_VALF_bytes    { 0, 0, 0x80, 0x7f }
  92 #  endif
  93
  94 static __huge_valf_t __huge_valf = { __HUGE_VALF_bytes };
  95 #  define HUGE_VALF     (__huge_valf.__f)
  96
  97 # endif /* GCC.  */
  98
  99
 100 /* Generally there is no separate `long double' format and it is the
 101    same as `double'.  */
 102 # define HUGE_VALL HUGE_VAL
 103
 104 #endif /* __USE_ISOC99.  */