diff --git a/sm4/asm_arm64.s b/sm4/asm_arm64.s
index 89aba6f..d282013 100644
--- a/sm4/asm_arm64.s
+++ b/sm4/asm_arm64.s
@@ -180,7 +180,7 @@ TEXT ·expandKeyAsm(SB),NOSPLIT,$0
   VEOR t3.B16, x.B16, x.B16
   VAND x.B16, NIBBLE_MASK.B16, XTMP7.B16
   VTBL XTMP7.B16, [M1L.B16], y.B16
-  VSRI $4, x.D2, x.D2
+  VSLI $-4, x.D2, x.D2
   //VAND x.B16, NIBBLE_MASK.B16, XTMP7.B16
   //VTBL XTMP7.B16, [M1H.B16], XTMP7.B16
   //VEOR y.B16, XTMP7.B16, x.B16