diff --git a/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.nasm b/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.nasm
index 134842a68a..31d8b0a717 100644
--- a/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.nasm
+++ b/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.nasm
@@ -1,7 +1,7 @@
 ;/** @file
 ;  Low level x64 routines used by the debug support driver.
 ;
-;  Copyright (c) 2007 - 2016, Intel Corporation. All rights reserved.<BR>
+;  Copyright (c) 2007 - 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
@@ -226,7 +226,7 @@ ASM_PFX(CommonIdtEntry):
                 pop     rax
                 add     rsp, 8                           ; pop vector number
                 mov     [AppRsp], rsp                    ; save stack top
-                mov     rsp, DebugStackBegin             ; switch to debugger stack
+                lea     rsp, [DebugStackBegin]           ; switch to debugger stack
                 sub     rsp, 8                           ; leave space for vector number
 
 ;; UINT64  Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
@@ -529,7 +529,7 @@ Chain:
                 push    rbx
                 mov     rax, cs
                 push    rax
-                mov     rax, PhonyIretq
+                lea     rax, [PhonyIretq]
                 push    rax
                 iretq
 PhonyIretq: