diff --git a/base64_arm64.s b/base64_arm64.s
index 87e605e..8433f69 100644
--- a/base64_arm64.s
+++ b/base64_arm64.s
@@ -63,7 +63,7 @@ TEXT ·decodeAsm(SB),NOSPLIT,$0
 
 	VLD1.P 64(R3), [V8.B16, V9.B16, V10.B16, V11.B16]
 	VLD1 (R3), [V12.B16, V13.B16, V14.B16, V15.B16]
-	MOVD $0x63, R4
+	MOVD $63, R4
 	VDUP R4, V7.B16
 
 loop: