sysdeps/m68k/s_isnanl.c

   1 /* Copyright (C) 1991, 1992, 1995, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library 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 GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <math.h>
  20 #include "ieee754.h"
  21
  22 #undef __isnanl
  23 #undef isnanl
  24
  25
  26 /* Return nonzero if VALUE is not a number.  */
  27 int
  28 __isnanl (long double value)
  29 {
  30   union ieee854_long_double u;
  31
  32   u.d = value;
  33
  34   /* IEEE 854 NaN's have the maximum possible
  35      exponent and a nonzero mantissa.  In Motorola's
  36      interpretation the integer bit is ignored.  */
  37   return ((u.ieee.exponent & 0x7fff) == 0x7fff &&
  38           ((u.ieee.mantissa0 & 0x7fffffff) != 0 || u.ieee.mantissa1 != 0));
  39 }
  40
  41 weak_alias (__isnanl, isnanl);