diff --git a/sm4/sm4_gcm_test.go b/sm4/sm4_gcm_test.go
index 2cec902..e1baf42 100644
--- a/sm4/sm4_gcm_test.go
+++ b/sm4/sm4_gcm_test.go
@@ -94,7 +94,7 @@ amd64 result = {
 	8F F3 05 10 EA 99 A8 D7 41 D9 E3 BA 67 D6 18 EE
 }
 arm64 result = {
-
+	8F F3 05 10 EA 99 A8 D7 41 D9 E3 BA 67 D6 18 EE
 }
 */
 func TestGcmSm4Finish(t *testing.T) {
@@ -108,3 +108,27 @@ func TestGcmSm4Finish(t *testing.T) {
 	}
 	fmt.Println()
 }
+
+func TestBothDataPlaintext(t *testing.T) {
+	g := genPrecomputeTable()
+	var tagOut, tagMask [gcmBlockSize]byte
+	data := []byte("emmansun")
+	gcmSm4Data(&g.bytesProductTable, data, &tagOut)
+	for j := 0; j < 16; j++ {
+		tagMask[j] = byte(j)
+	}
+	for j := 0; j < 16; j++ {
+		fmt.Printf("%02X ", tagOut[j])
+	}
+	fmt.Println()
+	gcmSm4Data(&g.bytesProductTable, []byte("emmansunemmansunemmansunemmansun"), &tagOut)
+	for j := 0; j < 16; j++ {
+		fmt.Printf("%02X ", tagOut[j])
+	}
+	fmt.Println()
+	gcmSm4Finish(&g.bytesProductTable, &tagMask, &tagOut, uint64(32), uint64(8))
+	for j := 0; j < 16; j++ {
+		fmt.Printf("%02X ", tagOut[j])
+	}
+	fmt.Println()
+}