; 29000 __gmpn_rshift -- ; Copyright (C) 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., 59 Temple Place - Suite 330, Boston, ; MA 02111-1307, 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_rshift .word 0x60000 ___gmpn_rshift: load 0,0,gr119,lr3 add lr3,lr3,4 subr gr116,lr5,32 sll 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,gr116 sub gr117,gr117,2 ; count for jmpfdec ; Main loop working 8 limbs/iteration. Loop: mtsrim cr,(8-1) loadm 0,0,gr100,lr3 add lr3,lr3,32 extract gr98,gr100,gr119 extract gr99,gr101,gr100 extract gr100,gr102,gr101 extract gr101,gr103,gr102 extract gr102,gr104,gr103 extract gr103,gr105,gr104 extract gr104,gr106,gr105 extract gr105,gr107,gr106 mtsrim cr,(8-1) storem 0,0,gr98,lr2 add lr2,lr2,32 jmpfdec gr117,Loop or gr119,gr107,0 ; 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: load 0,0,gr100,lr3 add lr3,lr3,4 extract gr117,gr100,gr119 store 0,0,gr117,lr2 add lr2,lr2,4 jmpfdec lr4,Loop2 or gr119,gr100,0 Lend: srl gr117,gr119,lr5 jmpi lr0 store 0,0,gr117,lr2