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/* AMD64 __mpn_rshift --
   Copyright (C) 2004, 2006 Free Software Foundation, Inc.
   This file is part of the GNU MP Library.

   The GNU MP 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 MP 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 MP 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"
#include "asm-syntax.h"

	.text
ENTRY (__mpn_rshift)
	movq	(%rsi), %mm7
	movd	%ecx, %mm1
	movl	$64, %eax
	subl	%ecx, %eax
	movd	%eax, %mm0
	movq	%mm7, %mm3
	psllq	%mm0, %mm7
	movd	%mm7, %rax
	leaq	(%rsi,%rdx,8), %rsi
	leaq	(%rdi,%rdx,8), %rdi
	negq	%rdx
	addq	$2, %rdx
	jg	L(endo)
	.p2align 2
L(loop):
	movq	-8(%rsi,%rdx,8), %mm6
	movq	%mm6, %mm2
	psllq	%mm0, %mm6
	psrlq	%mm1, %mm3
	por	%mm6, %mm3
	movq	%mm3, -16(%rdi,%rdx,8)
	je	L(ende)
	movq	(%rsi,%rdx,8), %mm7
	movq	%mm7, %mm3
	psllq	%mm0, %mm7
	psrlq	%mm1, %mm2
	por	%mm7, %mm2
	movq	%mm2, -8(%rdi,%rdx,8)
	addq	$2, %rdx
	jle	L(loop)
L(endo):
	movq	%mm3, %mm2
L(ende):
	psrlq	%mm1, %mm2
	movq	%mm2, -8(%rdi)
	emms
	ret
END (__mpn_rshift)