1 ;------------------------------------------------------------------------------ 2 ; 3 ; Copyright (c) 2006, 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 ; CopyMem function 19 ; 20 ; Notes: 21 ; 22 ;------------------------------------------------------------------------------ 23 24 SECTION .text 25 26 ;------------------------------------------------------------------------------ 27 ; VOID * 28 ; InternalMemCopyMem ( 29 ; IN VOID *Destination, 30 ; IN VOID *Source, 31 ; IN UINTN Count 32 ; ) 33 ;------------------------------------------------------------------------------ 34 global ASM_PFX(InternalMemCopyMem) 35 ASM_PFX(InternalMemCopyMem): 36 push esi 37 push edi 38 mov esi, [esp+16] ; esi <- Source 39 mov edi, [esp+12] ; edi <- Destination 40 mov edx, [esp+20] ; edx <- Count 41 cmp esi, edi 42 je @CopyDone 43 cmp edx, 0 44 je @CopyDone 45 lea eax, [esi + edx - 1] ; eax <- End of Source 46 cmp esi, edi 47 jae @CopyBytes 48 cmp eax, edi 49 jb @CopyBytes ; Copy backward if overlapped 50 mov esi, eax ; esi <- End of Source 51 lea edi, [edi + edx - 1] ; edi <- End of Destination 52 std 53 @CopyBytes: 54 mov ecx, edx 55 rep movsb ; Copy bytes backward 56 cld 57 @CopyDone: 58 mov eax, [esp + 12] ; eax <- Destination as return value 59 pop edi 60 pop esi 61 ret 62 63
