1;------------------------------------------------------------------------------ 2; 3; Copyright (c) 2007, Intel Corporation. All rights reserved.<BR> 4; This program and the accompanying materials 5; are licensed and made available under the terms and conditions of the BSD License 6; which accompanies this distribution. The full text of the license may be found at 7; http://opensource.org/licenses/bsd-license.php 8; 9; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 10; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 11; 12; Module Name: 13; 14; CopyMem.asm 15; 16; Abstract: 17; 18; memcpy function 19; 20; Notes: 21; 22;------------------------------------------------------------------------------ 23 24 .686 25 .model flat,C 26 .code 27 28;------------------------------------------------------------------------------ 29; VOID * 30; memcpy ( 31; IN VOID *Destination, 32; IN VOID *Source, 33; IN UINTN Count 34; ); 35;------------------------------------------------------------------------------ 36memcpy PROC USES esi edi 37 mov esi, [esp + 16] ; esi <- Source 38 mov edi, [esp + 12] ; edi <- Destination 39 mov edx, [esp + 20] ; edx <- Count 40 cmp esi, edi 41 je @CopyDone 42 cmp edx, 0 43 je @CopyDone 44 lea eax, [esi + edx - 1] ; eax <- End of Source 45 cmp esi, edi 46 jae @F 47 cmp eax, edi 48 jb @F ; Copy backward if overlapped 49 mov esi, eax ; esi <- End of Source 50 lea edi, [edi + edx - 1] ; edi <- End of Destination 51 std 52@@: 53 mov ecx, edx 54 rep movsb ; Copy bytes backward 55 cld 56@CopyDone: 57 mov eax, [esp + 12] 58 ret 59memcpy ENDP 60 61 END 62