mpir/mpn/x86w/lshift.asm

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; Copyright 1992, 1994, 1996, 1999, 2000, 2001, 2002 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.
;
; Translation of AT&T syntax code by Brian Gladman
%include "x86i.inc"
%define PARAM_SHIFT esp+frame+16
%define PARAM_SIZE esp+frame+12
%define PARAM_SRC esp+frame+8
%define PARAM_DST esp+frame+4
section .text
global ___gmpn_lshift
%ifdef DLL
export ___gmpn_lshift
%endif
align 8
___gmpn_lshift:
push edi
push esi
push ebx
%assign frame frame+12
mov edi,[PARAM_DST]
mov esi,[PARAM_SRC]
mov edx,[PARAM_SIZE]
mov ecx,[PARAM_SHIFT]
sub esi,4 ; adjust src
mov ebx,[esi+edx*4] ; read most significant limb
xor eax,eax
shld eax,ebx,cl
dec edx
jz Lend
push eax ; push carry limb onto stack
test dl,1
jnz L1 ; enter Lop in the middle
mov eax,ebx
align 8
Lop:
mov ebx,[esi+edx*4] ; load next lower limb
shld eax,ebx,cl
mov [edi+edx*4],eax ; store it
dec edx
L1:
mov eax,[esi+edx*4]
shld ebx,eax,cl
mov [edi+edx*4],ebx
dec edx
jnz Lop
shl eax,cl ; compute least significant limb
mov [edi],eax ; store it
pop eax ; pop carry limb
pop ebx
pop esi
pop edi
ret
Lend:
shl ebx,cl ; compute least significant limb
mov [edi],ebx ; store it
pop ebx
pop esi
pop edi
ret
end