+/** @file\r
+ Implementation of the EfiCopyMem routine. This function is broken\r
+ out into its own source file so that it can be excluded from a\r
+ build for a particular platform easily if an optimized version\r
+ is desired.\r
+\r
+ Copyright (c) 2006, Intel Corporation<BR>\r
+ All rights reserved. This program and the accompanying materials\r
+ are licensed and made available under the terms and conditions of the BSD License\r
+ which accompanies this distribution. The full text of the license may be found at\r
+ http://opensource.org/licenses/bsd-license.php\r
+\r
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
+\r
+ Module Name: EfiCopyMem.c\r
+\r
+**/\r
+\r
+//\r
+// Include common header file for this module.\r
+//\r
+#include "CommonHeader.h"\r
+\r
+#include "MemLibInternals.h"\r
+\r
+/**\r
+ Copy Length bytes from Source to Destination.\r
+\r
+ @param Destination Target of copy\r
+ @param Source Place to copy from\r
+ @param Length Number of bytes to copy\r
+\r
+ @return Destination\r
+\r
+**/\r
+VOID *\r
+EFIAPI\r
+InternalMemCopyMem (\r
+ OUT VOID *Destination,\r
+ IN CONST VOID *Source,\r
+ IN UINTN Length\r
+ )\r
+{\r
+ //\r
+ // Declare the local variables that actually move the data elements as\r
+ // volatile to prevent the optimizer from replacing this function with\r
+ // the intrinsic memcpy()\r
+ //\r
+ volatile UINT8 *Destination8;\r
+ CONST UINT8 *Source8;\r
+\r
+ if (Source > Destination) {\r
+ Destination8 = (UINT8*)Destination;\r
+ Source8 = (CONST UINT8*)Source;\r
+ while (Length-- != 0) {\r
+ *(Destination8++) = *(Source8++);\r
+ }\r
+ } else if (Source < Destination) {\r
+ Destination8 = (UINT8*)Destination + Length;\r
+ Source8 = (CONST UINT8*)Source + Length;\r
+ while (Length-- != 0) {\r
+ *(--Destination8) = *(--Source8);\r
+ }\r
+ }\r
+ return Destination;\r
+}\r