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/* Shift a limb right, low level routine.
   Copyright (C) 1995, 1997, 1999 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., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <sysdep.h>

/* INPUT PARAMETERS
   res_ptr	r3
   s1_ptr	r4
   size		r5
   cnt		r6  */

ENTRY(__mpn_rshift)
	mtctr	r5		# copy size into CTR
	addi	r7,r3,-4	# move adjusted res_ptr to free return reg
	subfic	r8,r6,32
	lwz	r11,0(r4)	# load first s1 limb
	slw	r3,r11,r8	# compute function return value
	bdz	1f

0:	lwzu	r10,4(r4)
	srw	r9,r11,r6
	slw	r12,r10,r8
	or	r9,r9,r12
	stwu	r9,4(r7)
	bdz	2f
	lwzu	r11,4(r4)
	srw	r9,r10,r6
	slw	r12,r11,r8
	or	r9,r9,r12
	stwu	r9,4(r7)
	bdnz	0b

1:	srw	r0,r11,r6
	stw	r0,4(r7)
	blr

2:	srw	r0,r10,r6
	stw	r0,4(r7)
	blr
END(__mpn_rshift)