1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
// Copyright 2017 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 "include/v8.h"
#include "src/api.h"
#include "src/objects-inl.h"
#include "src/objects/module.h"
#include "src/objects/script.h"
#include "src/objects/shared-function-info.h"
#include "test/cctest/cctest.h"
namespace v8 {
namespace internal {
namespace heap {
namespace {
v8::Local<v8::Object> ConstructTraceableJSApiObject(
v8::Local<v8::Context> context, void* first_field, void* second_field) {
v8::EscapableHandleScope scope(context->GetIsolate());
v8::Local<v8::FunctionTemplate> function_t =
v8::FunctionTemplate::New(context->GetIsolate());
v8::Local<v8::ObjectTemplate> instance_t = function_t->InstanceTemplate();
instance_t->SetInternalFieldCount(2);
v8::Local<v8::Function> function =
function_t->GetFunction(context).ToLocalChecked();
v8::Local<v8::Object> instance =
function->NewInstance(context).ToLocalChecked();
instance->SetAlignedPointerInInternalField(0, first_field);
instance->SetAlignedPointerInInternalField(1, second_field);
CHECK(!instance.IsEmpty());
i::Handle<i::JSReceiver> js_obj = v8::Utils::OpenHandle(*instance);
CHECK_EQ(i::JS_API_OBJECT_TYPE, js_obj->map()->instance_type());
return scope.Escape(instance);
}
class TestEmbedderHeapTracer final : public v8::EmbedderHeapTracer {
public:
explicit TestEmbedderHeapTracer(v8::Isolate* isolate) : isolate_(isolate) {}
void RegisterV8References(
const std::vector<std::pair<void*, void*>>& embedder_fields) final {
registered_from_v8_.insert(registered_from_v8_.end(),
embedder_fields.begin(), embedder_fields.end());
}
void AddReferenceForTracing(v8::Persistent<v8::Object>* persistent) {
to_register_with_v8_.push_back(persistent);
}
bool AdvanceTracing(double deadline_in_ms,
AdvanceTracingActions actions) final {
for (auto persistent : to_register_with_v8_) {
persistent->RegisterExternalReference(isolate_);
}
to_register_with_v8_.clear();
return false;
}
void TracePrologue() final {}
void TraceEpilogue() final {}
void AbortTracing() final {}
void EnterFinalPause() final {}
bool IsRegisteredFromV8(void* first_field) const {
for (auto pair : registered_from_v8_) {
if (pair.first == first_field) return true;
}
return false;
}
private:
v8::Isolate* const isolate_;
std::vector<std::pair<void*, void*>> registered_from_v8_;
std::vector<v8::Persistent<v8::Object>*> to_register_with_v8_;
};
} // namespace
TEST(V8RegisteringEmbedderReference) {
// Tests that wrappers are properly registered with the embedder heap
// tracer.
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
TestEmbedderHeapTracer tracer(isolate);
isolate->SetEmbedderHeapTracer(&tracer);
v8::HandleScope scope(isolate);
v8::Local<v8::Context> context = v8::Context::New(isolate);
v8::Context::Scope context_scope(context);
void* first_field = reinterpret_cast<void*>(0x2);
v8::Local<v8::Object> api_object =
ConstructTraceableJSApiObject(context, first_field, nullptr);
CHECK(!api_object.IsEmpty());
CcTest::CollectGarbage(i::OLD_SPACE);
CHECK(tracer.IsRegisteredFromV8(first_field));
}
TEST(EmbedderRegisteringV8Reference) {
// Tests that references that are registered by the embedder heap tracer are
// considered live by V8.
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
TestEmbedderHeapTracer tracer(isolate);
isolate->SetEmbedderHeapTracer(&tracer);
v8::HandleScope scope(isolate);
v8::Local<v8::Context> context = v8::Context::New(isolate);
v8::Context::Scope context_scope(context);
v8::Persistent<v8::Object> g;
{
v8::HandleScope inner_scope(isolate);
v8::Local<v8::Object> o =
v8::Local<v8::Object>::New(isolate, v8::Object::New(isolate));
g.Reset(isolate, o);
g.SetWeak();
}
tracer.AddReferenceForTracing(&g);
CcTest::CollectGarbage(i::OLD_SPACE);
CHECK(!g.IsEmpty());
}
namespace {
void ResurrectingFinalizer(
const v8::WeakCallbackInfo<v8::Global<v8::Object>>& data) {
data.GetParameter()->ClearWeak();
}
} // namespace
TEST(TracingInRevivedSubgraph) {
// Tests that wrappers are traced when they are contained with in a subgraph
// that is revived by a finalizer.
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
TestEmbedderHeapTracer tracer(isolate);
isolate->SetEmbedderHeapTracer(&tracer);
v8::HandleScope scope(isolate);
v8::Local<v8::Context> context = v8::Context::New(isolate);
v8::Context::Scope context_scope(context);
v8::Global<v8::Object> g;
void* first_field = reinterpret_cast<void*>(0x4);
{
v8::HandleScope inner_scope(isolate);
v8::Local<v8::Object> api_object =
ConstructTraceableJSApiObject(context, first_field, nullptr);
CHECK(!api_object.IsEmpty());
v8::Local<v8::Object> o =
v8::Local<v8::Object>::New(isolate, v8::Object::New(isolate));
o->Set(context, v8_str("link"), api_object).FromJust();
g.Reset(isolate, o);
g.SetWeak(&g, ResurrectingFinalizer, v8::WeakCallbackType::kFinalizer);
}
CcTest::CollectGarbage(i::OLD_SPACE);
CHECK(tracer.IsRegisteredFromV8(first_field));
}
TEST(TracingInEphemerons) {
// Tests that wrappers that are part of ephemerons are traced.
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
TestEmbedderHeapTracer tracer(isolate);
isolate->SetEmbedderHeapTracer(&tracer);
v8::HandleScope scope(isolate);
v8::Local<v8::Context> context = v8::Context::New(isolate);
v8::Context::Scope context_scope(context);
v8::Local<v8::Object> key =
v8::Local<v8::Object>::New(isolate, v8::Object::New(isolate));
void* first_field = reinterpret_cast<void*>(0x8);
i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
Handle<JSWeakMap> weak_map = i_isolate->factory()->NewJSWeakMap();
{
v8::HandleScope inner_scope(isolate);
v8::Local<v8::Object> api_object =
ConstructTraceableJSApiObject(context, first_field, nullptr);
CHECK(!api_object.IsEmpty());
Handle<JSObject> js_key =
handle(JSObject::cast(*v8::Utils::OpenHandle(*key)));
Handle<JSReceiver> js_api_object = v8::Utils::OpenHandle(*api_object);
int32_t hash = js_key->GetOrCreateHash(i_isolate)->value();
JSWeakCollection::Set(weak_map, js_key, js_api_object, hash);
}
CcTest::CollectGarbage(i::OLD_SPACE);
CHECK(tracer.IsRegisteredFromV8(first_field));
}
} // namespace heap
} // namespace internal
} // namespace v8
|
