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/* 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 __isinfl
#undef isinfl
/* Return 0 if VALUE is finite or NaN, +1 if it
is +Infinity, -1 if it is -Infinity. */
int
__isinfl (long double value)
{
union ieee854_long_double u;
u.d = value;
/* An IEEE 854 infinity has an exponent with the
maximum possible value and a zero mantissa.
In Motorola's interpretation the integer bit is ignored. */
if ((u.ieee.exponent & 0x7fff) == 0x7fff &&
(u.ieee.mantissa0 & 0x7fffffff) == 0 && u.ieee.mantissa1 == 0)
return u.ieee.negative ? -1 : 1;
return 0;
}
weak_alias (__isinfl, isinfl);
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