tests/test-round-ieee.c

   1 /* Test of rounding to nearest, breaking ties away from zero.
   2    Copyright (C) 2010-2011 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, or (at your option)
   7    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, write to the Free Software Foundation,
  16    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  17
  18 #include <config.h>
  19
  20 #include <math.h>
  21
  22 #include "minus-zero.h"
  23 #include "macros.h"
  24
  25 int
  26 main ()
  27 {
  28   /* See IEEE 754, section 6.3:
  29        "the sign of the result of the round floating-point number to
  30         integral value operation is the sign of the operand. These rules
  31         shall apply even when operands or results are zero or infinite."  */
  32
  33   /* Zero.  */
  34   ASSERT (!signbit (round (0.0)));
  35   ASSERT (!!signbit (round (minus_zerod)) == !!signbit (minus_zerod));
  36   /* Positive numbers.  */
  37   ASSERT (!signbit (round (0.3)));
  38   ASSERT (!signbit (round (0.7)));
  39   /* Negative numbers.  */
  40   ASSERT (!!signbit (round (-0.3)) == !!signbit (minus_zerod));
  41   ASSERT (!!signbit (round (-0.7)) == !!signbit (minus_zerod));
  42
  43   return 0;
  44 }