# Alpha 21064 __mpn_rshift --

 # Copyright (C) 1994-2018 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.  If not, see <http://www.gnu.org/licenses/>.

 # INPUT PARAMETERS

 # res_ptr	r16

 # s1_ptr	r17

 # size		r18

 # cnt		r19

 # This code runs at 4.8 cycles/limb on the 21064.  With infinite unrolling,

 # it would take 4 cycles/limb.  It should be possible to get down to 3

 # cycles/limb since both ldq and stq can be paired with the other used

 # instructions.  But there are many restrictions in the 21064 pipeline that

 # makes it hard, if not impossible, to get down to 3 cycles/limb:

 # 1. ldq has a 3 cycle delay, srl and sll have a 2 cycle delay.

 # 2. Only aligned instruction pairs can be paired.

 # 3. The store buffer or silo might not be able to deal with the bandwidth.

	.set	noreorder

	.set	noat

.text

	.align	3

	.globl	__mpn_rshift

	.ent	__mpn_rshift

__mpn_rshift:

	.frame	$30,0,$26,0

	ldq	$4,0($17)	# load first limb

	addq	$17,8,$17

	subq	$31,$19,$7

	subq	$18,1,$18

	and	$18,4-1,$20	# number of limbs in first loop

	sll	$4,$7,$0	# compute function result

	beq	$20,.L0

	subq	$18,$20,$18

	.align	3

.Loop0:

	ldq	$3,0($17)

	addq	$16,8,$16

	addq	$17,8,$17

	subq	$20,1,$20

	srl	$4,$19,$5

	sll	$3,$7,$6

	bis	$3,$3,$4

	bis	$5,$6,$8

	stq	$8,-8($16)

	bne	$20,.Loop0

.L0:	beq	$18,.Lend

	.align	3

.Loop:	ldq	$3,0($17)

	addq	$16,32,$16

	subq	$18,4,$18

	srl	$4,$19,$5

	sll	$3,$7,$6

	ldq	$4,8($17)

	srl	$3,$19,$1

	bis	$5,$6,$8

	stq	$8,-32($16)

	sll	$4,$7,$2

	ldq	$3,16($17)

	srl	$4,$19,$5

	bis	$1,$2,$8

	stq	$8,-24($16)

	sll	$3,$7,$6

	ldq	$4,24($17)

	srl	$3,$19,$1

	bis	$5,$6,$8

	stq	$8,-16($16)

	sll	$4,$7,$2

	addq	$17,32,$17

	bis	$1,$2,$8

	stq	$8,-8($16)

	bgt	$18,.Loop

.Lend:	srl	$4,$19,$8

	stq	$8,0($16)

	ret	$31,($26),1

	.end	__mpn_rshift