diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm
index 7c80a6ae91..fa02c1016c 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm
@@ -382,7 +382,7 @@ ASM_PFX(PageFaultIdtHandlerSmmProfile):
 ;; FX_SAVE_STATE_IA32 FxSaveState;
     sub     esp, 512
     mov     edi, esp
-    db      0xf, 0xae, 0x7 ;fxsave [edi]
+    fxsave  [edi]
 
 ; UEFI calling convention for IA32 requires that Direction flag in EFLAGs is clear
     cld
@@ -410,7 +410,7 @@ ASM_PFX(PageFaultIdtHandlerSmmProfile):
 
 ;; FX_SAVE_STATE_IA32 FxSaveState;
     mov     esi, esp
-    db      0xf, 0xae, 0xe ; fxrstor [esi]
+    fxrstor [esi]
     add     esp, 512
 
 ;; UINT32  Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
@@ -582,7 +582,7 @@ PFHandlerEntry:
     clts
     sub     esp, 512
     mov     edi, esp
-    db      0xf, 0xae, 0x7 ;fxsave [edi]
+    fxsave  [edi]
 
 ; UEFI calling convention for IA32 requires that Direction flag in EFLAGs is clear
     cld
@@ -612,7 +612,7 @@ PFHandlerEntry:
 
 ;; FX_SAVE_STATE_IA32 FxSaveState;
     mov     esi, esp
-    db      0xf, 0xae, 0xe ; fxrstor [esi]
+    fxrstor [esi]
     add     esp, 512
 
 ;; UINT32  Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm
index 5d731e2280..97c7b01d0d 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm
@@ -182,8 +182,7 @@ _SmiHandler:
     ; Save FP registers
     ;
     sub     rsp, 0x200
-    DB      0x48                         ; FXSAVE64
-    fxsave  [rsp]
+    fxsave64 [rsp]
 
     add     rsp, -0x20
 
@@ -201,8 +200,7 @@ _SmiHandler:
     ;
     ; Restore FP registers
     ;
-    DB      0x48                         ; FXRSTOR64
-    fxrstor [rsp]
+    fxrstor64 [rsp]
 
     add     rsp, 0x200
 
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiException.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiException.nasm
index a8a9af3008..98c40949f5 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiException.nasm
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiException.nasm
@@ -279,7 +279,7 @@ ASM_PFX(PageFaultIdtHandlerSmmProfile):
 
     sub rsp, 512
     mov rdi, rsp
-    db 0xf, 0xae, 00000111y ;fxsave [rdi]
+    fxsave [rdi]
 
 ; UEFI calling convention for x64 requires that Direction flag in EFLAGs is clear
     cld
@@ -309,7 +309,7 @@ ASM_PFX(PageFaultIdtHandlerSmmProfile):
 ;; FX_SAVE_STATE_X64 FxSaveState;
 
     mov rsi, rsp
-    db 0xf, 0xae, 00001110y ; fxrstor [rsi]
+    fxrstor [rsi]
     add rsp, 512
 
 ;; UINT64  Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;