mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-27 04:41:02 +08:00
47 lines
1.5 KiB
C
47 lines
1.5 KiB
C
/* Copyright (C) 1991, 1992, 1995, 1997, 2002 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;
|
|
}
|
|
|
|
INTDEF(__isinfl)
|
|
weak_alias (__isinfl, isinfl);
|