[wasm] Use weak reference for wasm deopt data.

src/wasm/wasm-module.h

 // 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.
 
 #ifndef V8_WASM_MODULE_H_
 #define V8_WASM_MODULE_H_
 
 #include <memory>
 
 #include "src/api.h"
@@ skipping 383 matching lines @@
                                       const WasmModule* module);
 
 // Populates a function table by replacing function indices with handles to
 // the compiled code.
 void PopulateFunctionTable(Handle<FixedArray> table, uint32_t table_size,
                            const std::vector<Handle<Code>>* code_table);
 
 Handle<JSObject> CreateCompiledModuleObject(Isolate* isolate,
                                             Handle<FixedArray> compiled_module);
 
+// Assumed to be called with a code object associated to a wasm module instance.
+// Intended to be called from runtime functions.
+// Returns undefined if the runtime support was not setup, nullptr if the
+// instance
+// was collected, or the instance object owning the Code object
+Object* GetOwningWasmInstance(Object* undefined, Code* code);
+
 namespace testing {
 
 // Decode, verify, and run the function labeled "main" in the
 // given encoded module. The module should have no imports.
 int32_t CompileAndRunWasmModule(Isolate* isolate, const byte* module_start,
                                 const byte* module_end, bool asm_js = false);
 
 int32_t CallFunction(Isolate* isolate, Handle<JSObject> instance,
                      ErrorThrower* thrower, const char* name, int argc,
                      Handle<Object> argv[]);
 }  // namespace testing
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_MODULE_H_