libgfortran/config/fpu-glibc.h

   1 /* FPU-related code for systems with GNU libc.
   2    Copyright (C) 2005-2014 Free Software Foundation, Inc.
   3    Contributed by Francois-Xavier Coudert <coudert@clipper.ens.fr>
   4
   5 This file is part of the GNU Fortran runtime library (libgfortran).
   6
   7 Libgfortran is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU General Public
   9 License as published by the Free Software Foundation; either
  10 version 3 of the License, or (at your option) any later version.
  11
  12 Libgfortran 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
  15 GNU General Public License for more details.
  16
  17 Under Section 7 of GPL version 3, you are granted additional
  18 permissions described in the GCC Runtime Library Exception, version
  19 3.1, as published by the Free Software Foundation.
  20
  21 You should have received a copy of the GNU General Public License and
  22 a copy of the GCC Runtime Library Exception along with this program;
  23 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 <http://www.gnu.org/licenses/>.  */
  25
  26 /* FPU-related code for systems with the GNU libc, providing the
  27    feenableexcept function in fenv.h to set individual exceptions
  28    (there's nothing to do that in C99).  */
  29
  30 #ifdef HAVE_FENV_H
  31 #include <fenv.h>
  32 #endif
  33
  34 void set_fpu (void)
  35 {
  36   if (FE_ALL_EXCEPT != 0)
  37     fedisableexcept (FE_ALL_EXCEPT);
  38
  39   if (options.fpe & GFC_FPE_INVALID)
  40 #ifdef FE_INVALID
  41     feenableexcept (FE_INVALID);
  42 #else
  43     estr_write ("Fortran runtime warning: IEEE 'invalid operation' "
  44                 "exception not supported.\n");
  45 #endif
  46
  47 /* glibc does never have a FE_DENORMAL.  */
  48   if (options.fpe & GFC_FPE_DENORMAL)
  49 #ifdef FE_DENORMAL
  50     feenableexcept (FE_DENORMAL);
  51 #else
  52     estr_write ("Fortran runtime warning: Floating point 'denormal operand' "
  53                 "exception not supported.\n");
  54 #endif
  55
  56   if (options.fpe & GFC_FPE_ZERO)
  57 #ifdef FE_DIVBYZERO
  58     feenableexcept (FE_DIVBYZERO);
  59 #else
  60     estr_write ("Fortran runtime warning: IEEE 'division by zero' "
  61                 "exception not supported.\n");
  62 #endif
  63
  64   if (options.fpe & GFC_FPE_OVERFLOW)
  65 #ifdef FE_OVERFLOW
  66     feenableexcept (FE_OVERFLOW);
  67 #else
  68     estr_write ("Fortran runtime warning: IEEE 'overflow' "
  69                 "exception not supported.\n");
  70 #endif
  71
  72   if (options.fpe & GFC_FPE_UNDERFLOW)
  73 #ifdef FE_UNDERFLOW
  74     feenableexcept (FE_UNDERFLOW);
  75 #else
  76     estr_write ("Fortran runtime warning: IEEE 'underflow' "
  77                 "exception not supported.\n");
  78 #endif
  79
  80   if (options.fpe & GFC_FPE_INEXACT)
  81 #ifdef FE_INEXACT
  82     feenableexcept (FE_INEXACT);
  83 #else
  84     estr_write ("Fortran runtime warning: IEEE 'inexact' "
  85                 "exception not supported.\n");
  86 #endif
  87 }
  88
  89
  90 int
  91 get_fpu_except_flags (void)
  92 {
  93   int result, set_excepts;
  94
  95   result = 0;
  96   set_excepts = fetestexcept (FE_ALL_EXCEPT);
  97
  98 #ifdef FE_INVALID
  99   if (set_excepts & FE_INVALID)
 100     result |= GFC_FPE_INVALID;
 101 #endif
 102
 103 #ifdef FE_DIVBYZERO
 104   if (set_excepts & FE_DIVBYZERO)
 105     result |= GFC_FPE_ZERO;
 106 #endif
 107
 108 #ifdef FE_OVERFLOW
 109   if (set_excepts & FE_OVERFLOW)
 110     result |= GFC_FPE_OVERFLOW;
 111 #endif
 112
 113 #ifdef FE_UNDERFLOW
 114   if (set_excepts & FE_UNDERFLOW)
 115     result |= GFC_FPE_UNDERFLOW;
 116 #endif
 117
 118 #ifdef FE_DENORMAL
 119   if (set_excepts & FE_DENORMAL)
 120     result |= GFC_FPE_DENORMAL;
 121 #endif
 122
 123 #ifdef FE_INEXACT
 124   if (set_excepts & FE_INEXACT)
 125     result |= GFC_FPE_INEXACT;
 126 #endif
 127
 128   return result;
 129 }
 130
 131
 132 int
 133 get_fpu_rounding_mode (void)
 134 {
 135   int rnd_mode;
 136
 137   rnd_mode = fegetround ();
 138
 139   switch (rnd_mode)
 140     {
 141 #ifdef FE_TONEAREST
 142       case FE_TONEAREST:
 143         return GFC_FPE_TONEAREST;
 144 #endif
 145
 146 #ifdef FE_UPWARD
 147       case FE_UPWARD:
 148         return GFC_FPE_UPWARD;
 149 #endif
 150
 151 #ifdef FE_DOWNWARD
 152       case FE_DOWNWARD:
 153         return GFC_FPE_DOWNWARD;
 154 #endif
 155
 156 #ifdef FE_TOWARDZERO
 157       case FE_TOWARDZERO:
 158         return GFC_FPE_TOWARDZERO;
 159 #endif
 160       default:
 161         return GFC_FPE_INVALID;
 162     }
 163 }
 164
 165
 166 void
 167 set_fpu_rounding_mode (int mode)
 168 {
 169   int rnd_mode;
 170
 171   switch (mode)
 172     {
 173 #ifdef FE_TONEAREST
 174       case GFC_FPE_TONEAREST:
 175         rnd_mode = FE_TONEAREST;
 176         break;
 177 #endif
 178
 179 #ifdef FE_UPWARD
 180       case GFC_FPE_UPWARD:
 181         rnd_mode = FE_UPWARD;
 182         break;
 183 #endif
 184
 185 #ifdef FE_DOWNWARD
 186       case GFC_FPE_DOWNWARD:
 187         rnd_mode = FE_DOWNWARD;
 188         break;
 189 #endif
 190
 191 #ifdef FE_TOWARDZERO
 192       case GFC_FPE_TOWARDZERO:
 193         rnd_mode = FE_TOWARDZERO;
 194         break;
 195 #endif
 196       default:
 197         return;
 198     }
 199
 200   fesetround (rnd_mode);
 201 }