;------------------------------------------------------------------------------ ; ; Copyright (c) 2006, Intel Corporation ; All rights reserved. This program and the accompanying materials ; are licensed and made available under the terms and conditions of the BSD License ; which accompanies this distribution. The full text of the license may be found at ; http://opensource.org/licenses/bsd-license.php ; ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. ; ; Module Name: ; ; CopyMem.Asm ; ; Abstract: ; ; CopyMem function ; ; Notes: ; ;------------------------------------------------------------------------------ .386 .model flat,C .code InternalMemCopyMem PROC USES esi edi mov esi, [esp + 16] ; esi <- Source mov edi, [esp + 12] ; edi <- Destination mov edx, [esp + 20] ; edx <- Count lea eax, [edi + edx - 1] ; eax <- End of Destination cmp esi, edi jae @F cmp eax, esi jae @CopyBackward ; Copy backward if overlapped @@: mov ecx, edx and edx, 3 shr ecx, 2 rep movsd ; Copy as many Dwords as possible jmp @CopyBytes @CopyBackward: mov edi, eax ; edi <- End of Destination lea esi, [esi + edx - 1] ; esi <- End of Source std @CopyBytes: mov ecx, edx rep movsb ; Copy bytes backward cld mov eax, [esp + 12] ; eax <- Destination as return value ret InternalMemCopyMem ENDP END