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+/* ix87 specific implementation of pow function.
+   Copyright (C) 1996 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
+
+   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 <machine/asm.h>
+
+#ifdef __ELF__
+	.section .rodata
+#else
+	.text
+#endif
+
+	.align ALIGNARG(4)
+	ASM_TYPE_DIRECTIVE(one,@object)
+one:	.double 1.0
+	ASM_SIZE_DIRECTIVE(one)
+	ASM_TYPE_DIRECTIVE(limit,@object)
+limit:	.double 0.29
+	ASM_SIZE_DIRECTIVE(limit)
+
+#ifdef PIC
+#define MO(op) op##@GOTOFF(%ecx)
+#else
+#define MO(op) op
+#endif
+
+	.text
+ENTRY(__ieee754_powl)
+	fldt	4(%esp)		// x
+	fldt	16(%esp)	// y : x
+
+#ifdef	PIC
+	call	1f
+1:	popl	%ecx
+	addl	$_GLOBAL_OFFSET_TABLE_+[.-1b], %ecx
+#endif
+	subl	$8,%esp
+
+	/* First see whether `y' is a natural number.  In this case we
+	   can use a more precise algorithm.  */
+	fld	%st		// y : y : x
+	fistpll	(%esp)		// y : x
+	fildll	(%esp)		// int(y) : y : x
+	fucomp	%st(1)		// y : x
+	fnstsw
+	sahf
+	jne	2f
+
+	/* OK, we have an integer value for y.  */
+	ftst			// y : x
+	fstp	%st(0)		// x
+	fnstsw
+	sahf
+	popl	%eax
+	popl	%edx
+	jnc	4f		// y >= 0, jump
+	fdivrl	MO(one)		// 1/x		(now referred to as x)
+	negl	%eax
+	adcl	$0, %edx
+	negl	%edx
+4:	fldl	MO(one)		// 1 : x
+	fxch
+
+6:	shrdl	$1, %edx, %eax
+	jnc	5f
+	fxch
+	fmul	%st(1)		// x : ST*x
+	fxch
+5:	fmul	%st(0), %st	// x*x : ST*x
+	movl	%eax, %ecx
+	orl	%edx, %ecx
+	jnz	6b
+	fstp	%st(0)		// ST*x
+	ret
+
+	.align ALIGNARG(4)
+2:	/* y is a real number.  */
+	fxch			// x : y
+	fldl	MO(one)		// 1.0 : x : y
+	fld	%st(1)		// x : 1.0 : x : y
+	fsub	%st(1)		// x-1 : 1.0 : x : y
+	fabs			// |x-1| : 1.0 : x : y
+	fcompl	MO(limit)	// 1.0 : x : y
+	fnstsw
+	fxch			// x : 1.0 : y
+	sahf
+	ja	7f
+	fsub	%st(1)		// x-1 : 1.0 : y
+	fyl2xp1			// log2(x) : y
+	jmp	8f
+
+7:	fyl2x			// log2(x) : y
+8:	fmul	%st(1)		// y*log2(x) : y
+	fst	%st(1)		// y*log2(x) : y*log2(x)
+	frndint			// int(y*log2(x)) : y*log2(x)
+	fsubr	%st, %st(1)	// int(y*log2(x)) : fract(y*log2(x))
+	fxch			// fract(y*log2(x)) : int(y*log2(x))
+	f2xm1			// 2^fract(y*log2(x))-1 : int(y*log2(x))
+	faddl	MO(one)		// 2^fract(y*log2(x)) : int(y*log2(x))
+	fscale			// 2^fract(y*log2(x))*2^int(y*log2(x)) : int(y*log2(x))
+	addl	$8, %esp
+	fstp	%st(1)		// 2^fract(y*log2(x))*2^int(y*log2(x))
+	ret
+END(__ieee754_powl)