diff --git a/sm4/gcm_arm64.s b/sm4/gcm_arm64.s
index 80fa535..dedf341 100644
--- a/sm4/gcm_arm64.s
+++ b/sm4/gcm_arm64.s
@@ -885,7 +885,7 @@ decOctetsEnc4Blocks1:
 		VREV32 B1.B16, T2.B16
 		VREV32 B2.B16, B2.B16
 		VREV32 B3.B16, B3.B16
-		TRANSPOSE_MATRIX(B0, B1, B2, B3)
+		TRANSPOSE_MATRIX(T1, T2, B2, B3)
 
 		// encryption first 4 blocks
 		PRE_TRANSPOSE_MATRIX(B4, B5, B6, B7)