1 files changed, 39 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/X64/InterlockedCompareExchange64.c b/MdePkg/Library/BaseLib/X64/InterlockedCompareExchange64.c
new file mode 100644
index 0000000000..8cd90b393b
--- /dev/null
+++ b/MdePkg/Library/BaseLib/X64/InterlockedCompareExchange64.c
@@ -0,0 +1,39 @@
+/** @file
+  InterlockedCompareExchange64 function
+
+  Copyright (c) 2006, 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.
+
+**/
+
+#if _MSC_EXTENSIONS
+
+//
+// Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics
+//
+__int64 _InterlockedCompareExchange64(
+   __int64 volatile * Destination,
+   __int64 Exchange,
+   __int64 Comperand
+);
+
+#pragma intrinsic(_InterlockedCompareExchange64)
+
+UINT64
+EFIAPI
+InternalSyncCompareExchange64 (
+  IN      UINT64                    *Value,
+  IN      UINT64                    CompareValue,
+  IN      UINT64                    ExchangeValue
+  )
+{
+  return _InterlockedCompareExchange64 (Value, ExchangeValue, CompareValue);
+}
+
+#endif