diff --git a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange32.S b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange32.S
index 90b1af11d7..ce2af34493 100644
--- a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange32.S
+++ b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange32.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006 - 2008, Intel Corporation
+# Copyright (c) 2006 - 2009, Intel Corporation
 # 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
@@ -33,5 +33,5 @@
 ASM_GLOBAL ASM_PFX(InternalSyncCompareExchange32)
 ASM_PFX(InternalSyncCompareExchange32):
     mov     %edx, %eax
-    lock    cmpxchg %r8d, (%rcx)
+    lock/cmpxchg %r8d, (%rcx)
     ret
diff --git a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.S b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.S
index 86b338e418..7b7b8e6a41 100644
--- a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.S
+++ b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedCompareExchange64.S
@@ -34,5 +34,5 @@
 ASM_GLOBAL ASM_PFX(InternalSyncCompareExchange64)
 ASM_PFX(InternalSyncCompareExchange64):
     mov     %rdx, %rax
-    lock    cmpxchg %r8,(%rcx)
+    lock/cmpxchg %r8,(%rcx)
     ret
diff --git a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedDecrement.S b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedDecrement.S
index 2cadd02699..a503a989a8 100644
--- a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedDecrement.S
+++ b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedDecrement.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006 - 2008, Intel Corporation
+# Copyright (c) 2006 - 2009, Intel Corporation
 # 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
@@ -31,6 +31,6 @@
 #------------------------------------------------------------------------------
 ASM_GLOBAL ASM_PFX(InternalSyncDecrement)
 ASM_PFX(InternalSyncDecrement):
-    lock    decl (%rcx)
-    mov     (%rcx), %eax
+    lock/decl (%rcx)
+    mov       (%rcx), %eax
     ret
diff --git a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedIncrement.S b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedIncrement.S
index e1d3a02f2d..873dd63f8f 100644
--- a/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedIncrement.S
+++ b/MdePkg/Library/BaseSynchronizationLib/X64/InterlockedIncrement.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006 - 2008, Intel Corporation
+# Copyright (c) 2006 - 2009, Intel Corporation
 # 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
@@ -31,6 +31,6 @@
 #------------------------------------------------------------------------------
 ASM_GLOBAL ASM_PFX(InternalSyncIncrement)
 ASM_PFX(InternalSyncIncrement):
-    lock    incl  (%rcx)
-    mov     (%rcx), %eax
+    lock/incl (%rcx)
+    mov       (%rcx), %eax
     ret