1// Copyright 2016 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#include "src/snapshot/serializer-common.h"
6
7#include "src/external-reference-table.h"
8#include "src/ic/stub-cache.h"
9#include "src/list-inl.h"
10#include "src/objects-inl.h"
11
12namespace v8 {
13namespace internal {
14
15ExternalReferenceEncoder::ExternalReferenceEncoder(Isolate* isolate) {
16  map_ = isolate->external_reference_map();
17#ifdef DEBUG
18  table_ = ExternalReferenceTable::instance(isolate);
19#endif  // DEBUG
20  if (map_ != nullptr) return;
21  map_ = new AddressToIndexHashMap();
22  ExternalReferenceTable* table = ExternalReferenceTable::instance(isolate);
23  for (uint32_t i = 0; i < table->size(); ++i) {
24    Address addr = table->address(i);
25    // Ignore duplicate API references.
26    if (table->is_api_reference(i) && !map_->Get(addr).IsNothing()) continue;
27    DCHECK(map_->Get(addr).IsNothing());
28    map_->Set(addr, i);
29    DCHECK(map_->Get(addr).IsJust());
30  }
31  isolate->set_external_reference_map(map_);
32}
33
34uint32_t ExternalReferenceEncoder::Encode(Address address) const {
35  Maybe<uint32_t> maybe_index = map_->Get(address);
36  if (maybe_index.IsNothing()) {
37    void* addr = address;
38    v8::base::OS::PrintError("Unknown external reference %p.\n", addr);
39    v8::base::OS::PrintError("%s", ExternalReferenceTable::ResolveSymbol(addr));
40    v8::base::OS::Abort();
41  }
42#ifdef DEBUG
43  table_->increment_count(maybe_index.FromJust());
44#endif  // DEBUG
45  return maybe_index.FromJust();
46}
47
48const char* ExternalReferenceEncoder::NameOfAddress(Isolate* isolate,
49                                                    Address address) const {
50  Maybe<uint32_t> maybe_index = map_->Get(address);
51  if (maybe_index.IsNothing()) return "<unknown>";
52  return ExternalReferenceTable::instance(isolate)->name(
53      maybe_index.FromJust());
54}
55
56void SerializedData::AllocateData(int size) {
57  DCHECK(!owns_data_);
58  data_ = NewArray<byte>(size);
59  size_ = size;
60  owns_data_ = true;
61  DCHECK(IsAligned(reinterpret_cast<intptr_t>(data_), kPointerAlignment));
62}
63
64// The partial snapshot cache is terminated by undefined. We visit the
65// partial snapshot...
66//  - during deserialization to populate it.
67//  - during normal GC to keep its content alive.
68//  - not during serialization. The partial serializer adds to it explicitly.
69DISABLE_CFI_PERF
70void SerializerDeserializer::Iterate(Isolate* isolate, ObjectVisitor* visitor) {
71  List<Object*>* cache = isolate->partial_snapshot_cache();
72  for (int i = 0;; ++i) {
73    // Extend the array ready to get a value when deserializing.
74    if (cache->length() <= i) cache->Add(Smi::kZero);
75    // During deserialization, the visitor populates the partial snapshot cache
76    // and eventually terminates the cache with undefined.
77    visitor->VisitPointer(&cache->at(i));
78    if (cache->at(i)->IsUndefined(isolate)) break;
79  }
80}
81
82bool SerializerDeserializer::CanBeDeferred(HeapObject* o) {
83  return !o->IsString() && !o->IsScript();
84}
85
86void SerializerDeserializer::RestoreExternalReferenceRedirectors(
87    List<AccessorInfo*>* accessor_infos) {
88  // Restore wiped accessor infos.
89  for (AccessorInfo* info : *accessor_infos) {
90    Foreign::cast(info->js_getter())
91        ->set_foreign_address(info->redirected_getter());
92  }
93}
94
95}  // namespace internal
96}  // namespace v8
97