tests/test-ieee754-h.c

   1 /* Test <ieee754.h>.
   2    Copyright 2018-2024 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 Paul Eggert.  */
  18
  19 #include <config.h>
  20
  21 #include <ieee754.h>
  22 #include <stdio.h>
  23
  24 static struct {
  25   float x;
  26   unsigned sign; unsigned exponent; unsigned frac;
  27 } const float_tests[] =
  28   {
  29    {0.0f, 0, 0, 0},
  30    {-0.0f, 1, 0, 0},
  31    {0.1f, 0, 0x7b, 0x4ccccd}
  32   };
  33
  34 static struct {
  35   double x;
  36   unsigned sign; unsigned exponent; unsigned frac_hi; unsigned frac_lo;
  37 } const double_tests[] =
  38   {
  39    {0.0, 0, 0, 0, 0},
  40    {-0.0, 1, 0, 0, 0},
  41    {0.1, 0, 0x3fb, 0x99999, 0x9999999a}
  42   };
  43
  44 int
  45 main (void)
  46 {
  47   int i;
  48
  49   for (i = 0; i < sizeof float_tests / sizeof *float_tests; i++)
  50     {
  51       union ieee754_float u;
  52       u.f = float_tests[i].x;
  53       if (float_tests[i].sign != u.ieee.negative)
  54         return 1;
  55       if (float_tests[i].exponent != u.ieee.exponent)
  56         return 2;
  57       if (float_tests[i].frac != u.ieee.mantissa)
  58         return 3;
  59     }
  60
  61   for (i = 0; i < sizeof double_tests / sizeof *double_tests; i++)
  62     {
  63       union ieee754_double u;
  64       u.d = double_tests[i].x;
  65       if (double_tests[i].sign != u.ieee.negative)
  66         return 4;
  67       if (double_tests[i].exponent != u.ieee.exponent)
  68         return 5;
  69       if (double_tests[i].frac_hi != u.ieee.mantissa0)
  70         return 6;
  71       if (double_tests[i].frac_lo != u.ieee.mantissa1)
  72         return 7;
  73     }
  74
  75   return 0;
  76 }