1 files changed, 31 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/Ia32/SwapBytes64.c b/MdePkg/Library/BaseLib/Ia32/SwapBytes64.c
new file mode 100644
index 0000000000..acd0b82841
--- /dev/null
+++ b/MdePkg/Library/BaseLib/Ia32/SwapBytes64.c
@@ -0,0 +1,31 @@
+/** @file
+  Implementation of 64-bit swap bytes
+
+  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
+
+UINT64
+EFIAPI
+InternalMathSwapBytes64 (
+  IN      UINT64                    Operand
+  )
+{
+  _asm {
+    mov     eax, dword ptr [Operand + 4]
+    mov     edx, dword ptr [Operand + 0]
+    bswap   eax
+    bswap   edx
+  }
+}
+
+#endif