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Import gmp 3.1

# IBM POWER __gmpn_rshift -- 

# Copyright (C) 1992, 1994, 1999, 2000 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.


# INPUT PARAMETERS
# res_ptr	r3
# s_ptr		r4
# size		r5
# cnt		r6

	.toc
	.globl	__gmpn_rshift
	.globl	.__gmpn_rshift
	.csect	__gmpn_rshift[DS]
__gmpn_rshift:
	.long	.__gmpn_rshift, TOC[tc0], 0
	.csect	.text[PR]
	.align	2
.__gmpn_rshift:
	sfi	8,6,32
	mtctr	5		# put limb count in CTR loop register
	l	0,0(4)		# read least significant limb
	ai	9,3,-4		# adjust res_ptr since it's offset in the stu:s
	sle	3,0,8		# compute carry limb, and init MQ register
	bdz	Lend2		# if just one limb, skip loop
	lu	0,4(4)		# read 2:nd least significant limb
	sleq	7,0,8		# compute least significant limb of result
	bdz	Lend		# if just two limb, skip loop
Loop:	lu	0,4(4)		# load next higher limb
	stu	7,4(9)		# store previous result during read latency
	sleq	7,0,8		# compute result limb
	bdn	Loop		# loop back until CTR is zero
Lend:	stu	7,4(9)		# store 2:nd most significant limb
Lend2:	sre	7,0,6		# compute most significant limb
	st      7,4(9)		# store it"				\
	br