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-rw-r--r--REORG.TODO/sysdeps/i386/fpu/s_fmaxl.S71
1 files changed, 71 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/i386/fpu/s_fmaxl.S b/REORG.TODO/sysdeps/i386/fpu/s_fmaxl.S
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+++ b/REORG.TODO/sysdeps/i386/fpu/s_fmaxl.S
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+/* Compute maximum of two numbers, regarding NaN as missing argument.
+   Copyright (C) 1997-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+
+	.text
+ENTRY(__fmaxl)
+	fldt	16(%esp)	// y
+	fxam
+	fnstsw
+	fldt	4(%esp)		// y : x
+
+	andb	$0x45, %ah
+	cmpb	$0x01, %ah
+	je	2f		// y == NaN
+
+	fxam
+	fnstsw
+	andb	$0x45, %ah
+	cmpb	$0x01, %ah
+	je	3f		// x == NaN
+
+	fucom	%st(1)
+	fnstsw
+	sahf
+	jnc	1f
+
+	fxch	%st(1)
+1:	fstp	%st(1)
+
+	ret
+
+2:	// st(1) is a NaN; st(0) may or may not be.
+	fxam
+	fnstsw
+	andb	$0x45, %ah
+	cmpb	$0x01, %ah
+	je	4f
+	// st(1) is a NaN; st(0) is not.  Test if st(1) is signaling.
+	testb	$0x40, 23(%esp)
+	jz	4f
+	fstp	%st(1)
+	ret
+
+3:	// st(0) is a NaN; st(1) is not.  Test if st(0) is signaling.
+	testb	$0x40, 11(%esp)
+	jz	4f
+	fstp	%st(0)
+	ret
+
+4:	// Both arguments are NaNs, or one is a signaling NaN.
+	faddp
+	ret
+END(__fmaxl)
+weak_alias (__fmaxl, fmaxl)