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diff --git a/roms/edk2/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.c b/roms/edk2/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.c
new file mode 100644
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+++ b/roms/edk2/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.c
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+/** @file
+  InterlockedCompareExchange64 function
+
+  Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+/**
+  Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics.
+**/
+
+__int64 _InterlockedCompareExchange64(
+   __int64 volatile * Destination,
+   __int64 Exchange,
+   __int64 Comperand
+);
+
+#pragma intrinsic(_InterlockedCompareExchange64)
+
+/**
+  Performs an atomic compare exchange operation on a 64-bit unsigned integer.
+
+  Performs an atomic compare exchange operation on the 64-bit unsigned integer specified
+  by Value.  If Value is equal to CompareValue, then Value is set to ExchangeValue and
+  CompareValue is returned.  If Value is not equal to CompareValue, then Value is returned.
+  The compare exchange operation must be performed using MP safe mechanisms.
+
+  @param  Value         A pointer to the 64-bit value for the compare exchange
+                        operation.
+  @param  CompareValue  64-bit value used in compare operation.
+  @param  ExchangeValue 64-bit value used in exchange operation.
+
+  @return The original *Value before exchange.
+
+**/
+UINT64
+EFIAPI
+InternalSyncCompareExchange64 (
+  IN      volatile UINT64           *Value,
+  IN      UINT64                    CompareValue,
+  IN      UINT64                    ExchangeValue
+  )
+{
+  return _InterlockedCompareExchange64 (Value, ExchangeValue, CompareValue);
+}
+