;------------------------------------------------------------------------------ ; ; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR> ; 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: ; ;------------------------------------------------------------------------------ SECTION .text ;------------------------------------------------------------------------------ ; VOID * ; InternalMemCopyMem ( ; IN VOID *Destination, ; IN VOID *Source, ; IN UINTN Count ; ) ;------------------------------------------------------------------------------ global ASM_PFX(InternalMemCopyMem) ASM_PFX(InternalMemCopyMem): push esi push edi mov esi, [esp + 16] ; esi <- Source mov edi, [esp + 12] ; edi <- Destination mov edx, [esp + 20] ; edx <- Count lea eax, [esi + edx - 1] ; eax <- End of Source cmp esi, edi jae .0 cmp eax, edi jae @CopyBackward ; Copy backward if overlapped .0: mov ecx, edx and edx, 3 shr ecx, 2 rep movsd ; Copy as many Dwords as possible jmp @CopyBytes @CopyBackward: mov esi, eax ; esi <- End of Source lea edi, [edi + edx - 1] ; edi <- End of Destination std @CopyBytes: mov ecx, edx rep movsb ; Copy bytes backward cld mov eax, [esp + 12] ; eax <- Destination as return value pop edi pop esi ret