[wasm] test deserialization when header is invalid

test/cctest/wasm/test-run-wasm-module.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 <stdlib.h>
 #include <string.h>
 
 #include "src/wasm/module-decoder.h"
 #include "src/wasm/wasm-macro-gen.h"
 #include "src/wasm/wasm-module-builder.h"
@@ skipping 209 matching lines @@
   }
 
   v8::WasmCompiledModule::UncompiledBytes uncompressed_bytes = {
       std::unique_ptr<const uint8_t[]>(const_cast<const uint8_t*>(bytes)),
       bytes_size};
 
   v8::Isolate::CreateParams create_params;
   create_params.array_buffer_allocator =
       CcTest::InitIsolateOnce()->array_buffer_allocator();
 
-  for (int i = 0; i < 2; ++i) {
+  for (int i = 0; i < 3; ++i) {
     v8::Isolate* v8_isolate = v8::Isolate::New(create_params);
     if (i == 1) {
-      // Mess with the serialized data to force recompilation.
+      // Mess the header.

[bradnelson, 2016/10/12 19:10:25]

Mess with?

[Mircea Trofin, 2016/10/12 20:32:06]

Done.

+      DCHECK_NE(0, data.first.get()[0]);
+      const_cast<uint8_t*>(data.first.get())[0] = 0;

[bradnelson, 2016/10/12 19:10:25]

Kinda bad. Maybe create an accessor that's a friend on a test fixture?

[Mircea Trofin, 2016/10/12 20:32:06]

Done.

+    }
+
+    if (i == 2) {
+      // Reset the compiled module data.
       data.first.reset();
       data.second = 0;
     }
     {
       v8::Isolate::Scope isolate_scope(v8_isolate);
       v8::HandleScope new_scope(v8_isolate);
       v8::Local<v8::Context> new_ctx = v8::Context::New(v8_isolate);
       new_ctx->Enter();
       isolate = reinterpret_cast<Isolate*>(v8_isolate);
       testing::SetupIsolateForWasmModule(isolate);
@@ skipping 283 matching lines @@
 
 TEST(Run_WasmModule_Global_f32) {
   RunWasmModuleGlobalInitTest<float>(kAstF32, -983.9f);
   RunWasmModuleGlobalInitTest<float>(kAstF32, 1122.99f);
 }
 
 TEST(Run_WasmModule_Global_f64) {
   RunWasmModuleGlobalInitTest<double>(kAstF64, -833.9);
   RunWasmModuleGlobalInitTest<double>(kAstF64, 86374.25);
 }