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 DEFAULT REL 25 SECTION .text 26 27 ;------------------------------------------------------------------------------ 28 ; VOID * 29 ; EFIAPI 30 ; InternalMemCopyMem ( 31 ; IN VOID *Destination, 32 ; IN VOID *Source, 33 ; IN UINTN Count 34 ; ) 35 ;------------------------------------------------------------------------------ 36 global ASM_PFX(InternalMemCopyMem) 37 ASM_PFX(InternalMemCopyMem): 38 push rsi 39 push rdi 40 mov rsi, rdx ; rsi <- Source 41 mov rdi, rcx ; rdi <- Destination 42 lea r9, [rsi + r8 - 1] ; r9 <- End of Source 43 cmp rsi, rdi 44 mov rax, rdi ; rax <- Destination as return value 45 jae .0 46 cmp r9, rdi 47 jae @CopyBackward ; Copy backward if overlapped 48 .0: 49 mov rcx, r8 50 and r8, 7 51 shr rcx, 3 52 rep movsq ; Copy as many Qwords as possible 53 jmp @CopyBytes 54 @CopyBackward: 55 mov rsi, r9 ; rsi <- End of Source 56 lea rdi, [rdi + r8 - 1] ; esi <- End of Destination 57 std ; set direction flag 58 @CopyBytes: 59 mov rcx, r8 60 rep movsb ; Copy bytes backward 61 cld 62 pop rdi 63 pop rsi 64 ret 65 66
