mpir/mpn/a29k/lshift.s

94 lines
2.2 KiB
ArmAsm

; 29000 __gmpn_lshift --
; Copyright 1992, 1994, 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., 51 Franklin Street, Fifth Floor, Boston,
; MA 02110-1301, USA.
; INPUT PARAMETERS
; res_ptr lr2
; s1_ptr lr3
; s2_ptr lr4
; size lr5
; We use the loadm/storem instructions and operate on chunks of 8
; limbs/per iteration, until less than 8 limbs remain.
.sect .lit,lit
.text
.align 4
.global ___gmpn_lshift
.word 0x60000
___gmpn_lshift:
sll gr116,lr4,2
add lr3,gr116,lr3
add lr2,gr116,lr2
sub lr3,lr3,4
load 0,0,gr119,lr3
subr gr116,lr5,32
srl gr96,gr119,gr116 ; return value
sub lr4,lr4,1 ; actual loop count is SIZE - 1
srl gr117,lr4,3 ; chuck count = (actual count) / 8
cpeq gr118,gr117,0
jmpt gr118,Ltail
mtsr fc,lr5
sub gr117,gr117,2 ; count for jmpfdec
; Main loop working 8 limbs/iteration.
Loop: sub lr3,lr3,32
mtsrim cr,(8-1)
loadm 0,0,gr100,lr3
extract gr109,gr119,gr107
extract gr108,gr107,gr106
extract gr107,gr106,gr105
extract gr106,gr105,gr104
extract gr105,gr104,gr103
extract gr104,gr103,gr102
extract gr103,gr102,gr101
extract gr102,gr101,gr100
sub lr2,lr2,32
mtsrim cr,(8-1)
storem 0,0,gr102,lr2
jmpfdec gr117,Loop
or gr119,gr100,0
; Code for the last up-to-7 limbs.
and lr4,lr4,(8-1)
Ltail: cpeq gr118,lr4,0
jmpt gr118,Lend
sub lr4,lr4,2 ; count for jmpfdec
Loop2: sub lr3,lr3,4
load 0,0,gr116,lr3
extract gr117,gr119,gr116
sub lr2,lr2,4
store 0,0,gr117,lr2
jmpfdec lr4,Loop2
or gr119,gr116,0
Lend: extract gr117,gr119,0
sub lr2,lr2,4
jmpi lr0
store 0,0,gr117,lr2