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-rwxr-xr-xArmPkg/Library/BaseMemoryLibVstm/CopyMem.c62
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diff --git a/ArmPkg/Library/BaseMemoryLibVstm/CopyMem.c b/ArmPkg/Library/BaseMemoryLibVstm/CopyMem.c
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+/** @file
+ Implementation of the InternalMemCopyMem routine. This function is broken
+ out into its own source file so that it can be excluded from a build for a
+ particular platform easily if an optimized version is desired.
+
+ Copyright (c) 2006 - 2008, Intel Corporation<BR>
+ 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.
+
+**/
+
+
+
+
+#include "MemLibInternals.h"
+
+/**
+ Copy Length bytes from Source to Destination.
+
+ @param DestinationBuffer Target of copy
+ @param SourceBuffer Place to copy from
+ @param Length Number of bytes to copy
+
+ @return Destination
+
+**/
+VOID *
+EFIAPI
+InternalMemCopyMem (
+ OUT VOID *DestinationBuffer,
+ IN CONST VOID *SourceBuffer,
+ IN UINTN Length
+ )
+{
+ //
+ // Declare the local variables that actually move the data elements as
+ // volatile to prevent the optimizer from replacing this function with
+ // the intrinsic memcpy()
+ //
+ volatile UINT8 *Destination8;
+ CONST UINT8 *Source8;
+
+ if (SourceBuffer > DestinationBuffer) {
+ Destination8 = (UINT8*)DestinationBuffer;
+ Source8 = (CONST UINT8*)SourceBuffer;
+ while (Length-- != 0) {
+ *(Destination8++) = *(Source8++);
+ }
+ } else if (SourceBuffer < DestinationBuffer) {
+ Destination8 = (UINT8*)DestinationBuffer + Length;
+ Source8 = (CONST UINT8*)SourceBuffer + Length;
+ while (Length-- != 0) {
+ *(--Destination8) = *(--Source8);
+ }
+ }
+ return DestinationBuffer;
+}