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 lea eax, [esi + edx - 1] ; eax <- End of Source 42 cmp esi, edi 43 jae .0 44 cmp eax, edi 45 jae @CopyBackward ; Copy backward if overlapped 46 .0: 47 mov ecx, edx 48 and edx, 3 49 shr ecx, 2 50 rep movsd ; Copy as many Dwords as possible 51 jmp @CopyBytes 52 @CopyBackward: 53 mov esi, eax ; esi <- End of Source 54 lea edi, [edi + edx - 1] ; edi <- End of Destination 55 std 56 @CopyBytes: 57 mov ecx, edx 58 rep movsb ; Copy bytes backward 59 cld 60 mov eax, [esp + 12] ; eax <- Destination as return value 61 pop edi 62 pop esi 63 ret 64 65
