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authorRoland McGrath <roland@gnu.org>1995-11-16 00:44:18 +0000
committerRoland McGrath <roland@gnu.org>1995-11-16 00:44:18 +0000
commitec967c06ac7474fa58266ea309d6488ee3c53851 (patch)
treedcea408ef904d340938ac85866816b4c024319d8 /sysdeps/i386/isinfl.c
parent2ede96c9362f1950ef309f4fb9662aea60fe9777 (diff)
Wed Nov 15 19:22:07 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* sysdeps/mach/hurd/dl-sysdep.c: Include _itoa.h from stdio-common instead of stdio. (_dl_sysdep_start): If passed user entry is zero and EXEC_STACK_ARGS flag set, reset user entry to &_start. * elf/rtld.c (dl_main): Only call _dl_setup_hash if there is a DT_HASH element. * libc-symbols.h [HAVE_ELF] (symbol_set_declare): Gratuitously repeat weak decl using weak_symbol macro, in case using broken GCC (<2.8). Wed Nov 15 18:49:55 1995 Ulrich Drepper <drepper@ipd.info.uni-karlsruhe.de> * sysdeps/i386/isnanl.c: New file. * sysdeps/i386/isinfl.c: New file.
Diffstat (limited to 'sysdeps/i386/isinfl.c')
-rw-r--r--sysdeps/i386/isinfl.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/sysdeps/i386/isinfl.c b/sysdeps/i386/isinfl.c
new file mode 100644
index 0000000000..056d756d58
--- /dev/null
+++ b/sysdeps/i386/isinfl.c
@@ -0,0 +1,46 @@
+/* Check `long double' for Infinity. i386 FPU version.
+Copyright (C) 1991, 1992, 1995 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, 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;
+
+ /* Intel's interpretation of the IEEE 854 standard defines Inf to
+ have the maximum possible exponent and the MSB of the mantissa
+ set. No further bit of the mantissa must be set. */
+ if ((u.ieee.exponent & 0x7fff) == 0x7fff &&
+ u.ieee.mantissa0 == 0x80000000 && u.ieee.mantissa1 == 0)
+ return u.ieee.negative ? -1 : 1;
+
+ return 0;
+}
+
+weak_alias (__isinfl, isinfl);