glibc/sysdeps/m68k/s_isnanl.c

42 lines
1.3 KiB
C

/* Copyright (C) 1991, 1992, 1995, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <math.h>
#include "ieee754.h"
#undef __isnanl
#undef isnanl
/* Return nonzero if VALUE is not a number. */
int
__isnanl (long double value)
{
union ieee854_long_double u;
u.d = value;
/* IEEE 854 NaN's have the maximum possible
exponent and a nonzero mantissa. In Motorola's
interpretation the integer bit is ignored. */
return ((u.ieee.exponent & 0x7fff) == 0x7fff &&
((u.ieee.mantissa0 & 0x7fffffff) != 0 || u.ieee.mantissa1 != 0));
}
weak_alias (__isnanl, isnanl);