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+/* 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"
+
+/* 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;
+}
+
+hidden_def (__isinfl)
+weak_alias (__isinfl, isinfl);