[wasm] Introduce WasmSharedModuleData and refactor other objects

src/snapshot/code-serializer.cc

 // Copyright 2016 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 "src/snapshot/code-serializer.h"
 
 #include <memory>
 
 #include "src/code-stubs.h"
 #include "src/log.h"
@@ skipping 213 matching lines @@
   return scope.CloseAndEscape(result);
 }
 
 std::unique_ptr<ScriptData> WasmCompiledModuleSerializer::SerializeWasmModule(
     Isolate* isolate, Handle<FixedArray> input) {
   Handle<WasmCompiledModule> compiled_module =
       Handle<WasmCompiledModule>::cast(input);
   WasmCompiledModuleSerializer wasm_cs(isolate, 0);
   wasm_cs.reference_map()->AddAttachedReference(*isolate->native_context());
   wasm_cs.reference_map()->AddAttachedReference(
-      *compiled_module->module_bytes());
+      compiled_module->module_bytes());
   ScriptData* data = wasm_cs.Serialize(compiled_module);
   return std::unique_ptr<ScriptData>(data);
 }
 
 MaybeHandle<FixedArray> WasmCompiledModuleSerializer::DeserializeWasmModule(
     Isolate* isolate, ScriptData* data, Vector<const byte> wire_bytes) {
   SerializedCodeData::SanityCheckResult sanity_check_result =
       SerializedCodeData::CHECK_SUCCESS;
   MaybeHandle<FixedArray> nothing;
   const SerializedCodeData scd = SerializedCodeData::FromCachedData(
@@ skipping 16 matching lines @@
       handle(SeqOneByteString::cast(*wire_bytes_as_string)));
 
   Vector<const uint32_t> stub_keys = scd.CodeStubKeys();
   for (int i = 0; i < stub_keys.length(); ++i) {
     deserializer.AddAttachedObject(
         CodeStub::GetCode(isolate, stub_keys[i]).ToHandleChecked());
   }
 
   MaybeHandle<HeapObject> obj = deserializer.DeserializeObject(isolate);
   if (obj.is_null() || !obj.ToHandleChecked()->IsFixedArray()) return nothing;
-  Handle<WasmCompiledModule> compiled_module =
-      Handle<WasmCompiledModule>::cast(obj.ToHandleChecked());
+  // Cast without type checks, as the module wrapper is not there yet.
+  Handle<WasmCompiledModule> compiled_module(
+      static_cast<WasmCompiledModule*>(*obj.ToHandleChecked()), isolate);
 
   WasmCompiledModule::RecreateModuleWrapper(isolate, compiled_module);
+  DCHECK(WasmCompiledModule::IsWasmCompiledModule(*compiled_module));
   return compiled_module;
 }
 
 class Checksum {
  public:
   explicit Checksum(Vector<const byte> payload) {
 #ifdef MEMORY_SANITIZER
     // Computing the checksum includes padding bytes for objects like strings.
     // Mark every object as initialized in the code serializer.
     MSAN_MEMORY_IS_INITIALIZED(payload.start(), payload.length());
@@ skipping 150 matching lines @@
   *rejection_result = scd.SanityCheck(isolate, expected_source_hash);
   if (*rejection_result != CHECK_SUCCESS) {
     cached_data->Reject();
     return SerializedCodeData(nullptr, 0);
   }
   return scd;
 }
 
 }  // namespace internal
 }  // namespace v8