[wasm] Enforce that function bodies end with the \"end\" opcode.

test/cctest/wasm/test-run-wasm.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 <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "src/base/platform/elapsed-timer.h"
 #include "src/utils.h"
@@ skipping 1833 matching lines @@
   HandleScope scope(isolate);
   // Enable all optional operators.
   CommonOperatorBuilder common(&zone);
   MachineOperatorBuilder machine(&zone, MachineType::PointerRepresentation(),
                                  MachineOperatorBuilder::kAllOptionalOps);
   Graph graph(&zone);
   JSGraph jsgraph(isolate, &graph, &common, nullptr, nullptr, &machine);
   FunctionSig* sig = WasmOpcodes::Signature(opcode);
 
   if (sig->parameter_count() == 1) {
-    byte code[] = {WASM_NO_LOCALS, kExprGetLocal, 0, static_cast<byte>(opcode)};
+    byte code[] = {WASM_NO_LOCALS, kExprGetLocal, 0, static_cast<byte>(opcode),
+                   WASM_END};
     TestBuildingGraph(&zone, &jsgraph, nullptr, sig, nullptr, code,
                       code + arraysize(code));
   } else {
     CHECK_EQ(2, sig->parameter_count());
-    byte code[] = {WASM_NO_LOCALS,           kExprGetLocal, 0, kExprGetLocal, 1,
-                   static_cast<byte>(opcode)};
+    byte code[] = {WASM_NO_LOCALS,
+                   kExprGetLocal,
+                   0,
+                   kExprGetLocal,
+                   1,
+                   static_cast<byte>(opcode),
+                   WASM_END};
     TestBuildingGraph(&zone, &jsgraph, nullptr, sig, nullptr, code,
                       code + arraysize(code));
   }
 }
 
 TEST(Build_Wasm_SimpleExprs) {
 // Test that the decoder can build a graph for all supported simple expressions.
 #define GRAPH_BUILD_TEST(name, opcode, sig) \
   TestBuildGraphForSimpleExpression(kExpr##name);
 
@@ skipping 988 matching lines @@
   BUILD(r, WASM_I32_REMS(WASM_GET_LOCAL(0), WASM_GET_LOCAL(1)), WASM_DROP,
         WASM_ZERO);
   const int32_t kMin = std::numeric_limits<int32_t>::min();
   CHECK_EQ(0, r.Call(133, 100));
   CHECK_EQ(0, r.Call(kMin, -1));
   CHECK_EQ(0, r.Call(0, 1));
   CHECK_TRAP(r.Call(100, 0));
   CHECK_TRAP(r.Call(-1001, 0));
   CHECK_TRAP(r.Call(kMin, 0));
 }