tests/test-isnand.h

   1 /* Test of isnand() substitute.
   2    Copyright (C) 2007-2019 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2007.  */
  18
  19 #include <limits.h>
  20
  21 #include "minus-zero.h"
  22 #include "infinity.h"
  23 #include "nan.h"
  24 #include "macros.h"
  25
  26 int
  27 main ()
  28 {
  29   /* Finite values.  */
  30   ASSERT (!isnand (3.141));
  31   ASSERT (!isnand (3.141e30));
  32   ASSERT (!isnand (3.141e-30));
  33   ASSERT (!isnand (-2.718));
  34   ASSERT (!isnand (-2.718e30));
  35   ASSERT (!isnand (-2.718e-30));
  36   ASSERT (!isnand (0.0));
  37   ASSERT (!isnand (minus_zerod));
  38   /* Infinite values.  */
  39   ASSERT (!isnand (Infinityd ()));
  40   ASSERT (!isnand (- Infinityd ()));
  41   /* Quiet NaN.  */
  42   ASSERT (isnand (NaNd ()));
  43 #if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
  44   /* Signalling NaN.  */
  45   {
  46     #define NWORDS \
  47       ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
  48     typedef union { double value; unsigned int word[NWORDS]; } memory_double;
  49     memory_double m;
  50     m.value = NaNd ();
  51 # if DBL_EXPBIT0_BIT > 0
  52     m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
  53 # else
  54     m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
  55       ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
  56 # endif
  57     m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
  58       |= (unsigned int) 1 << DBL_EXPBIT0_BIT;
  59     ASSERT (isnand (m.value));
  60   }
  61 #endif
  62   return 0;
  63 }