kolibrios/programs/develop/open watcom/trunk/clib/cgsupp/__copy.asm

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;*****************************************************************************
;*
;* Open Watcom Project
;*
;* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
;*
;* ========================================================================
;*
;* This file contains Original Code and/or Modifications of Original
;* Code as defined in and that are subject to the Sybase Open Watcom
;* Public License version 1.0 (the 'License'). You may not use this file
;* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
;* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
;* provided with the Original Code and Modifications, and is also
;* available at www.sybase.com/developer/opensource.
;*
;* The Original Code and all software distributed under the License are
;* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
;* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
;* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
;* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
;* NON-INFRINGEMENT. Please see the License for the specific language
;* governing rights and limitations under the License.
;*
;* ========================================================================
;*
;* Description: WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
;* DESCRIBE IT HERE!
;*
;*****************************************************************************
;
; char *__COPY( char *dst, char *src, unsigned len );
;
;
include mdef.inc
name __copy
_TEXT segment use32 para public 'CODE'
assume cs:_TEXT
public __COPY
public __COPY_
__COPY proc near
__COPY_ proc near
push edi ; save regs
push esi ; ...
push ecx ; ...
mov edi,16+0[esp] ; get dst
mov esi,16+4[esp] ; get src
mov ecx,16+8[esp] ; get len
mov eax,edi ; return with dst ptr in eax
shr ecx,2 ; calc. # of dwords
rep movsd ; do the copy
mov ecx,16+8[esp] ; get len
and ecx,3 ; plus extra bytes
rep movsb ; do the copy
pop ecx ; restore regs
pop esi ; ...
pop edi ; ...
ret 12 ; return and remove parms
__COPY_ endp
__COPY endp
_TEXT ends
end