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+/* Compute the hypothenuse of X and Y.
+   Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
+
+   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., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <sysdep.h>
+
+	.text
+ENTRY(__ieee754_hypotf)
+	flds	4(%esp)		// x
+	fxam
+	fnstsw
+	flds	8(%esp)		// y : x
+	movb	%ah, %ch
+	fxam
+	fnstsw
+	movb	%ah, %al
+	orb	%ch, %ah
+	sahf
+	jc	1f
+	fmul	%st(0)		// y * y : x
+	fxch			// x : y * y
+	fmul	%st(0)		// x * x : y * y
+	faddp			// x * x + y * y
+	fsqrt
+2:	ret
+
+	// We have to test whether any of the parameters is Inf.
+	// In this case the result is infinity.
+1:	andb	$0x45, %al
+	cmpb	$5, %al
+	je	3f		// jump if y is Inf
+	andb	$0x45, %ch
+	cmpb	$5, %ch
+	jne	4f		// jump if x is not Inf
+	fxch
+3:	fstp	%st(1)
+	fabs
+	jmp	2b
+
+4:	testb	$1, %al
+	jnz	5f		// y is NaN
+	fxch
+5:	fstp	%st(1)
+	jmp	2b
+	
+END(__ieee754_hypotf)