1// Copyright 2017 the V8 project authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#if !V8_ENABLE_WEBASSEMBLY
6#error This header should only be included if WebAssembly is enabled.
7#endif  // !V8_ENABLE_WEBASSEMBLY
8
9#ifndef V8_WASM_WASM_SERIALIZATION_H_
10#define V8_WASM_WASM_SERIALIZATION_H_
11
12#include "src/wasm/wasm-code-manager.h"
13#include "src/wasm/wasm-objects.h"
14
15namespace v8 {
16namespace internal {
17namespace wasm {
18
19// Support for serializing WebAssembly {NativeModule} objects. This class takes
20// a snapshot of the module state at instantiation, and other code that modifies
21// the module after that won't affect the serialized result.
22class V8_EXPORT_PRIVATE WasmSerializer {
23 public:
24  explicit WasmSerializer(NativeModule* native_module);
25
26  // Measure the required buffer size needed for serialization.
27  size_t GetSerializedNativeModuleSize() const;
28
29  // Serialize the {NativeModule} into the provided {buffer}. Returns true on
30  // success and false if the given buffer it too small for serialization.
31  bool SerializeNativeModule(base::Vector<byte> buffer) const;
32
33  // The data header consists of uint32_t-sized entries (see {WriteVersion}):
34  // [0] magic number
35  // [1] version hash
36  // [2] supported CPU features
37  // [3] flag hash
38  // ...  number of functions
39  // ... serialized functions
40  static constexpr size_t kMagicNumberOffset = 0;
41  static constexpr size_t kVersionHashOffset = kMagicNumberOffset + kUInt32Size;
42  static constexpr size_t kSupportedCPUFeaturesOffset =
43      kVersionHashOffset + kUInt32Size;
44  static constexpr size_t kFlagHashOffset =
45      kSupportedCPUFeaturesOffset + kUInt32Size;
46  static constexpr size_t kHeaderSize = 4 * kUInt32Size;
47
48 private:
49  NativeModule* native_module_;
50  // The {WasmCodeRefScope} keeps the pointers in {code_table_} alive.
51  WasmCodeRefScope code_ref_scope_;
52  std::vector<WasmCode*> code_table_;
53};
54
55// Support for deserializing WebAssembly {NativeModule} objects.
56// Checks the version header of the data against the current version.
57bool IsSupportedVersion(base::Vector<const byte> data);
58
59// Deserializes the given data to create a Wasm module object.
60V8_EXPORT_PRIVATE MaybeHandle<WasmModuleObject> DeserializeNativeModule(
61    Isolate*, base::Vector<const byte> data,
62    base::Vector<const byte> wire_bytes, base::Vector<const char> source_url);
63
64}  // namespace wasm
65}  // namespace internal
66}  // namespace v8
67
68#endif  // V8_WASM_WASM_SERIALIZATION_H_
69