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// 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-inl.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(EmbedderStackState) 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_;
};
class TemporaryEmbedderHeapTracerScope {
public:
TemporaryEmbedderHeapTracerScope(v8::Isolate* isolate,
EmbedderHeapTracer* tracer)
: isolate_(isolate) {
isolate_->SetEmbedderHeapTracer(tracer);
}
~TemporaryEmbedderHeapTracerScope() {
isolate_->SetEmbedderHeapTracer(nullptr);
}
private:
v8::Isolate* const isolate_;
};
} // 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);
TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &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);
TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &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);
TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &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);
TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &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)), i_isolate);
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));
}
TEST(FinalizeTracingIsNoopWhenNotMarking) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
Isolate* i_isolate = CcTest::i_isolate();
TestEmbedderHeapTracer tracer(isolate);
TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
// Finalize a potentially running garbage collection.
i_isolate->heap()->CollectGarbage(OLD_SPACE,
GarbageCollectionReason::kTesting);
CHECK(i_isolate->heap()->incremental_marking()->IsStopped());
int gc_counter = i_isolate->heap()->gc_count();
tracer.FinalizeTracing();
CHECK(i_isolate->heap()->incremental_marking()->IsStopped());
CHECK_EQ(gc_counter, i_isolate->heap()->gc_count());
}
TEST(FinalizeTracingWhenMarking) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
Isolate* i_isolate = CcTest::i_isolate();
TestEmbedderHeapTracer tracer(isolate);
TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
// Finalize a potentially running garbage collection.
i_isolate->heap()->CollectGarbage(OLD_SPACE,
GarbageCollectionReason::kTesting);
if (i_isolate->heap()->mark_compact_collector()->sweeping_in_progress()) {
i_isolate->heap()->mark_compact_collector()->EnsureSweepingCompleted();
}
CHECK(i_isolate->heap()->incremental_marking()->IsStopped());
i::IncrementalMarking* marking = i_isolate->heap()->incremental_marking();
marking->Start(i::GarbageCollectionReason::kTesting);
// Sweeping is not runing so we should immediately start marking.
CHECK(marking->IsMarking());
tracer.FinalizeTracing();
CHECK(marking->IsStopped());
}
TEST(GarbageCollectionForTesting) {
ManualGCScope manual_gc;
i::FLAG_expose_gc = true;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
Isolate* i_isolate = CcTest::i_isolate();
TestEmbedderHeapTracer tracer(isolate);
TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
int saved_gc_counter = i_isolate->heap()->gc_count();
tracer.GarbageCollectionForTesting(EmbedderHeapTracer::kUnknown);
CHECK_GT(i_isolate->heap()->gc_count(), saved_gc_counter);
}
} // namespace heap
} // namespace internal
} // namespace v8
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