[wasm] Unreachability fix for br_table.

test/unittests/wasm/function-body-decoder-unittest.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "test/unittests/test-utils.h"
 
 #include "src/v8.h"
 
 #include "test/common/wasm/test-signatures.h"
 
@@ skipping 2115 matching lines @@
     byte code[] = {
         WASM_LOOP(WASM_BR_TABLE(WASM_GET_LOCAL(0), 0, BR_TARGET(depth)))};
     if (depth < 2) {
       EXPECT_VERIFIES_C(v_i, code);
     } else {
       EXPECT_FAILURE_C(v_i, code);
     }
   }
 }
 
+TEST_F(FunctionBodyDecoderTest, BrUnreachable) {
+  static byte code[] = {WASM_GET_LOCAL(0), kExprBrTable,  0,
+                        BR_TARGET(0),      kExprSetLocal, 0};
+  EXPECT_VERIFIES_C(v_i, code);
+}
+
 TEST_F(FunctionBodyDecoderTest, Brv1) {
   EXPECT_VERIFIES(i_i, WASM_BLOCK_I(WASM_BRV(0, WASM_ZERO)));
   EXPECT_VERIFIES(i_i, WASM_BLOCK_I(WASM_LOOP(WASM_BRV(2, WASM_ZERO))));
 }
 
 TEST_F(FunctionBodyDecoderTest, Brv1_type) {
   EXPECT_VERIFIES(i_ii, WASM_BLOCK_I(WASM_BRV(0, WASM_GET_LOCAL(0))));
   EXPECT_VERIFIES(l_ll, WASM_BLOCK_L(WASM_BRV(0, WASM_GET_LOCAL(0))));
   EXPECT_VERIFIES(f_ff, WASM_BLOCK_F(WASM_BRV(0, WASM_GET_LOCAL(0))));
   EXPECT_VERIFIES(d_dd, WASM_BLOCK_D(WASM_BRV(0, WASM_GET_LOCAL(0))));
@@ skipping 619 matching lines @@
   iter.next();
   EXPECT_TRUE(iter.has_next());
   EXPECT_EQ(kExprI32Const, iter.current());
   iter.next();
   EXPECT_FALSE(iter.has_next());
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8