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/*++
Copyright (c) 2007, Intel Corporation
All rights reserved. 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:
EfiCopyMemRep4.c
Abstract:
This is the code that uses rep movsd CopyMem service
--*/
#include "Tiano.h"
VOID
EfiCommonLibCopyMem (
IN VOID *Destination,
IN VOID *Source,
IN UINTN Count
)
/*++
Routine Description:
Copy Length bytes from Source to Destination.
Arguments:
Destination - Target of copy
Source - Place to copy from
Length - Number of bytes to copy
Returns:
None
--*/
{
__asm {
mov esi, Source ; esi <- Source
mov edi, Destination ; edi <- Destination
mov edx, Count ; edx <- Count
cmp esi, edi
je _CopyDone
cmp edx, 0
je _CopyDone
lea eax, [esi + edx - 1] ; eax <- End of Source
cmp esi, edi
jae _CopyDWord
cmp eax, edi
jae _CopyBackward ; Copy backward if overlapped
_CopyDWord:
mov ecx, edx
and edx, 3
shr ecx, 2
rep movsd ; Copy as many Dwords as possible
jmp _CopyBytes
_CopyBackward:
mov esi, eax ; esi <- End of Source
lea edi, [edi + edx - 1] ; edi <- End of Destination
std
_CopyBytes:
mov ecx, edx
rep movsb ; Copy bytes backward
cld
_CopyDone:
}
}
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