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
11 namespace v8 {
12 namespace internal {
13
ExternalReferenceEncoder(Isolate * isolate)14 ExternalReferenceEncoder::ExternalReferenceEncoder(Isolate* isolate) {
15 map_ = isolate->external_reference_map();
16 if (map_ != NULL) return;
17 map_ = new base::HashMap(base::HashMap::PointersMatch);
18 ExternalReferenceTable* table = ExternalReferenceTable::instance(isolate);
19 for (int i = 0; i < table->size(); ++i) {
20 Address addr = table->address(i);
21 if (addr == ExternalReferenceTable::NotAvailable()) continue;
22 // We expect no duplicate external references entries in the table.
23 // AccessorRefTable getter may have duplicates, indicated by an empty string
24 // as name.
25 DCHECK(table->name(i)[0] == '\0' ||
26 map_->Lookup(addr, Hash(addr)) == nullptr);
27 map_->LookupOrInsert(addr, Hash(addr))->value = reinterpret_cast<void*>(i);
28 }
29 isolate->set_external_reference_map(map_);
30 }
31
Encode(Address address) const32 uint32_t ExternalReferenceEncoder::Encode(Address address) const {
33 DCHECK_NOT_NULL(address);
34 base::HashMap::Entry* entry =
35 const_cast<base::HashMap*>(map_)->Lookup(address, Hash(address));
36 DCHECK_NOT_NULL(entry);
37 return static_cast<uint32_t>(reinterpret_cast<intptr_t>(entry->value));
38 }
39
NameOfAddress(Isolate * isolate,Address address) const40 const char* ExternalReferenceEncoder::NameOfAddress(Isolate* isolate,
41 Address address) const {
42 base::HashMap::Entry* entry =
43 const_cast<base::HashMap*>(map_)->Lookup(address, Hash(address));
44 if (entry == NULL) return "<unknown>";
45 uint32_t i = static_cast<uint32_t>(reinterpret_cast<intptr_t>(entry->value));
46 return ExternalReferenceTable::instance(isolate)->name(i);
47 }
48
AllocateData(int size)49 void SerializedData::AllocateData(int size) {
50 DCHECK(!owns_data_);
51 data_ = NewArray<byte>(size);
52 size_ = size;
53 owns_data_ = true;
54 DCHECK(IsAligned(reinterpret_cast<intptr_t>(data_), kPointerAlignment));
55 }
56
57 // The partial snapshot cache is terminated by undefined. We visit the
58 // partial snapshot...
59 // - during deserialization to populate it.
60 // - during normal GC to keep its content alive.
61 // - not during serialization. The partial serializer adds to it explicitly.
Iterate(Isolate * isolate,ObjectVisitor * visitor)62 void SerializerDeserializer::Iterate(Isolate* isolate, ObjectVisitor* visitor) {
63 List<Object*>* cache = isolate->partial_snapshot_cache();
64 for (int i = 0;; ++i) {
65 // Extend the array ready to get a value when deserializing.
66 if (cache->length() <= i) cache->Add(Smi::FromInt(0));
67 // During deserialization, the visitor populates the partial snapshot cache
68 // and eventually terminates the cache with undefined.
69 visitor->VisitPointer(&cache->at(i));
70 if (cache->at(i)->IsUndefined(isolate)) break;
71 }
72 }
73
CanBeDeferred(HeapObject * o)74 bool SerializerDeserializer::CanBeDeferred(HeapObject* o) {
75 return !o->IsString() && !o->IsScript();
76 }
77
78 } // namespace internal
79 } // namespace v8
80