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/* PowerPC-32 lshift
 *
 *	Copyright (C) 1995, 1998 Free Software Foundation, Inc.
 *
 * This file is part of GnuPG.
 *
 * GnuPG is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * GnuPG 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */


/*******************
 * mpi_limb_t
 * mpihelp_lshift( mpi_ptr_t wp,	(r3)
 *		   mpi_ptr_t up,	(r4)
 *		   mpi_size_t usize,	(r5)
 *		   unsigned cnt)	(r6)
 */

	.toc
.csect	.text[PR]
	.align	2
	.globl	mpihelp_lshift
	.globl	.mpihelp_lshift
	.csect	mpihelp_lshift[DS]
mpihelp_lshift:
	.long	.mpihelp_lshift,  TOC[tc0],	  0
	.csect	.text[PR]
.mpihelp_lshift:
	mtctr	5		# copy size into CTR
	slwi	0,5,2
	add	7,3,0		# make r7 point at end of res
	add	4,4,0		# make r4 point at end of s1
	subfic	8,6,32
	lwzu	11,-4(4)	# load first s1 limb
	srw	3,11,8		# compute function return value
	bdz	Lend1

Loop:	lwzu	10,-4(4)
	slw	9,11,6
	srw	12,10,8
	or	9,9,12
	stwu	9,-4(7)
	bdz	Lend2
	lwzu	11,-4(4)
	slw	9,10,6
	srw	12,11,8
	or	9,9,12
	stwu	9,-4(7)
	bdnz	Loop

Lend1:	slw	0,11,6
	stw	0,-4(7)
	blr

Lend2:	slw	0,10,6
	stw	0,-4(7)
	blr