; i80586 rshift
;
;      Copyright (C) 1992, 1994, 1995, 1996, 1998,
;                    2001 Free Software Foundation, Inc.
;
; This file is part of GnuPG.
;
; GnuPG is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
;
; GnuPG 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 General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, write to the Free Software
; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
;
; Modified versions of the GPG i586 assembler for use with NASM.  This 
; file is part of a native port of Gnu PG for use with Microsoft Visual 
; Studio .net. Ported by Brian Gladman <brg@gladman.uk.net> March 2002.

	global	_mpihelp_rshift

	section	.text
	align	8
	
_mpihelp_rshift:
    push    edi
    push    esi
    push    ebx
    push    ebp
    mov     edi,[20+esp]
    mov     esi,[24+esp]
    mov     ebp,[28+esp]
    mov     ecx,[32+esp]
	cmp     ecx,1
    jne     short .1
    lea     eax,[4+edi]
    cmp     eax,esi
    jnc     .6
    lea     eax,[edi+ebp*4]
    cmp     esi,eax
    jnc     .6
.1: 
    mov     edx,[esi]
    add     esi,4
    xor     eax,eax
    shrd    eax,edx,cl
    push    eax
    dec     ebp
    push    ebp
    shr     ebp,3
    jz      short .3
    mov     eax, [edi]
    
    align	4
.2:	mov     eax,[28+edi]
    mov     ebx,edx
    mov     eax,[esi]
    mov     edx,[4+esi]
    shrd    ebx,eax,cl
    shrd    eax,edx,cl
    mov     [edi],ebx
    mov     [4+edi],eax
    mov     ebx,[8+esi]
    mov     eax,[12+esi]
    shrd    edx,ebx,cl
    shrd    ebx,eax,cl
    mov     [8+edi],edx
    mov     [12+edi],ebx
    mov     edx,[16+esi]
    mov     ebx,[20+esi]
    shrd    eax,edx,cl
    shrd    edx,ebx,cl
    mov     [16+edi],eax
    mov     [20+edi],edx
    mov     eax,[24+esi]
    mov     edx,[28+esi]
    shrd    ebx,eax,cl
    shrd    eax,edx,cl
    mov     [24+edi],ebx
    mov     [28+edi],eax
    add     esi,32
    add     edi,32
    dec     ebp
    jnz     short .2
.3: pop     ebp
    and     ebp,7
    jz      .5
.4:  
	mov     eax,[esi]
    shrd    edx,eax,cl
    mov     [edi],edx
    mov     edx,eax
    add     esi,4
    add     edi,4
    dec     ebp
    jnz     short .4

.5: shr     edx,cl
    mov     [edi],edx
    pop     eax
    pop     ebp
    pop     ebx
    pop     esi
    pop     edi
    ret

.6: 
    lea     edi,[-4+edi+ebp*4]
    lea     esi,[-4+esi+ebp*4]
    mov     edx,[esi]
    sub     esi,4
    dec     ebp
    push    ebp
    shr     ebp,3
    shr     edx,1
    inc     ebp
    dec     ebp
    jz      short .8
    mov     eax, [edi]
    
    align	4
.7: mov     eax,[-28+edi]
    mov     ebx,edx
    mov     eax,[esi]
    mov     edx,[-4+esi]
    rcr     eax,1
    mov     [edi],ebx
    rcr     edx,1
    mov     [-4+edi],eax
    mov     ebx,[-8+esi]
    mov     eax,[-12+esi]
    rcr     ebx,1
    mov     [-8+edi],edx
    rcr     eax,1
    mov     [-12+edi],ebx
    mov     edx,[-16+esi]
    mov     ebx,[-20+esi]
    rcr     edx,1
    mov     [-16+edi],eax
    rcr     ebx,1
    mov     [-20+edi],edx
    mov     eax,[-24+esi]
    mov     edx,[-28+esi]
    rcr     eax,1
    mov     [-24+edi],ebx
    rcr     edx,1
    mov     [-28+edi],eax
    lea     esi,[-32+esi]
    lea     edi,[-32+edi]
    dec     ebp
    jnz     short .7

.8:  
	pop     ebp
    sbb     eax,eax
    and     ebp,7
    jz      .10
    add     eax,eax
.9: 
	mov     ebx,edx
    mov     edx,[esi]
    rcr     edx,1
    mov     [edi],ebx
    lea     esi,[-4+esi]
    lea     edi,[-4+edi]
    dec     ebp
    jnz     short .9
	jmp     short .11

.10:add     eax,eax
.11:mov     [edi],edx
    mov     eax,0
    rcr     eax,1
    pop     ebp
    pop     ebx
    pop     esi
    pop     edi
    ret
    
    end