;------------------------------------------------------------------------------

;

; 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:

;

;------------------------------------------------------------------------------

.code

;------------------------------------------------------------------------------

; VOID *

; EFIAPI

; InternalMemCopyMem (

; OUT VOID *DestinationBuffer,

; IN CONST VOID *SourceBuffer,

; IN UINTN Length

; );

;------------------------------------------------------------------------------

InternalMemCopyMem PROC USES rsi rdi

mov rsi, rdx ; rsi <- Source

mov rdi, rcx ; rdi <- Destination

lea r9, [rsi + r8 - 1] ; r9 <- End of Source

cmp rsi, rdi

mov rax, rdi ; rax <- Destination as return value

jae @F

cmp r9, rdi

jae @CopyBackward ; Copy backward if overlapped

@@:

mov rcx, r8

and r8, 7

shr rcx, 3 ; rcx <- # of Qwords to copy

jz @CopyBytes

DB 49h, 0fh, 7eh, 0c2h ; movd r10, mm0 (Save mm0 in r10)

@@:

DB 0fh, 6fh, 06h ; movd mm0, [rsi]

DB 0fh, 0e7h, 07h ; movntq [rdi], mm0

add rsi, 8

add rdi, 8

loop @B

mfence

DB 49h, 0fh, 6eh, 0c2h ; movd mm0, r10 (Restore mm0)

jmp @CopyBytes

@CopyBackward:

mov rsi, r9 ; rsi <- End of Source

lea rdi, [rdi + r8 - 1] ; rdi <- End of Destination

std ; set direction flag

@CopyBytes:

mov rcx, r8

rep movsb ; Copy bytes backward

cld

ret

InternalMemCopyMem ENDP

END