1 files changed, 37 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/X64/Lfence.nasm b/MdePkg/Library/BaseLib/X64/Lfence.nasm
new file mode 100644
index 0000000000..9ee9b563e2
--- /dev/null
+++ b/MdePkg/Library/BaseLib/X64/Lfence.nasm
@@ -0,0 +1,37 @@
+;------------------------------------------------------------------------------ ;
+; Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>
+; 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.
+;
+; Module Name:
+;
+;   Lfence.nasm
+;
+; Abstract:
+;
+;   Performs a serializing operation on all load-from-memory instructions that
+;   were issued prior to the call of this function.
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+; VOID
+; EFIAPI
+; AsmLfence (
+;   VOID
+;   );
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmLfence)
+ASM_PFX(AsmLfence):
+    lfence
+    ret