diff --git a/MdePkg/Library/BaseMemoryLibOptDxe/Ia32/SetMem.S b/MdePkg/Library/BaseMemoryLibOptDxe/Ia32/SetMem.S
index 441f347c2f..726ccd76fb 100644
--- a/MdePkg/Library/BaseMemoryLibOptDxe/Ia32/SetMem.S
+++ b/MdePkg/Library/BaseMemoryLibOptDxe/Ia32/SetMem.S
@@ -21,9 +21,6 @@
 #
 #------------------------------------------------------------------------------
 
-    .386:
-    .code:
-
 .globl ASM_PFX(InternalMemSetMem)
 
 #------------------------------------------------------------------------------
@@ -38,18 +35,16 @@ ASM_PFX(InternalMemSetMem):
     push    %edi
     movl    12(%esp),%ecx
     movb    16(%esp),%al
-    movb    %ah, %al
+    movb    %al, %ah
     shrd    $16, %eax, %edx
     shld    $16, %edx, %eax
-    movl    %edx, %ecx
-    movl    8(%esp),%edi
-    shrd    $2, %ecx, %ecx
-    rep 
-    stosl
     movl    %ecx, %edx
+    movl    8(%esp),%edi
+    shr    $2, %ecx
+    rep stosl
+    movl    %edx, %ecx
     andl    $3, %ecx
-    rep
-    stosb
+    rep stosb
     movl    8(%esp),%eax
     pop     %edi
     ret