1 ;------------------------------------------------------------------------------
3 ; Copyright (c) 2007, Intel Corporation
4 ; All rights reserved. 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
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.
22 ;------------------------------------------------------------------------------
26 ;------------------------------------------------------------------------------
28 ; EfiCommonLibCopyMem (
29 ; OUT VOID *Destination,
33 ;------------------------------------------------------------------------------
34 EfiCommonLibCopyMem PROC USES rsi rdi
35 cmp rdx, rcx ; if Source == Destination, do nothing
37 cmp r8, 0 ; if Count == 0, do nothing
39 mov rsi, rdx ; rsi <- Source
40 mov rdi, rcx ; rdi <- Destination
41 lea r9, [rsi + r8 - 1] ; r9 <- End of Source
43 mov rax, rdi ; rax <- Destination as return value
44 jae @F ; Copy forward if Source > Destination
45 cmp r9, rdi ; Overlapped?
46 jae @CopyBackward ; Copy backward if overlapped
49 sub rcx, rdi ; rcx <- -rdi
50 and rcx, 15 ; rcx + rsi should be 16 bytes aligned
51 jz @F ; skip if rcx == 0
59 shr rcx, 4 ; rcx <- # of DQwords to copy
62 movdqu xmm0, [rsi] ; rsi may not be 16-byte aligned
63 movdqa [rdi], xmm0 ; rdi should be 16-byte aligned
67 jmp @CopyBytes ; copy remaining bytes
69 mov rsi, r9 ; rsi <- Last byte of Source
70 lea rdi, [rdi + r8 - 1] ; rdi <- Last byte of Destination
78 EfiCommonLibCopyMem ENDP