v8/test/cctest/heap/test-embedder-tracing.cc
Michael Lippautz debbfe4ebd api: Add trait that allows disabling v8::TracedGlobal<T> destructor
TracedGlobal is already cleared by V8 during garbage collections. It's
the embedders responsibility to clear the reference if it destroys the
underlying reference through other means.

Allow embedders to specify whether they want TracedGlobal to execute
clear on destruction via TracedGlobalTrait.

Bug: chromium:995684
Change-Id: Ieb10cf21f95eb97e01eff15d4fbd83538f17cf7c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1762007
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63289}
2019-08-20 16:38:39 +00:00

643 lines
22 KiB
C++

// 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 <unordered_map>
#include <vector>
#include "include/v8.h"
#include "src/api/api-inl.h"
#include "src/heap/heap-inl.h"
#include "src/objects/module.h"
#include "src/objects/objects-inl.h"
#include "src/objects/script.h"
#include "src/objects/shared-function-info.h"
#include "test/cctest/cctest.h"
#include "test/cctest/heap/heap-utils.h"
namespace v8 {
// See test below: TracedGlobalNoDestructor.
template <>
struct TracedGlobalTrait<v8::TracedGlobal<v8::Value>> {
static constexpr bool kRequiresExplicitDestruction = false;
};
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);
}
enum class TracePrologueBehavior { kNoop, kCallV8WriteBarrier };
class TestEmbedderHeapTracer final : public v8::EmbedderHeapTracer {
public:
TestEmbedderHeapTracer() = default;
TestEmbedderHeapTracer(TracePrologueBehavior prologue_behavior,
v8::Global<v8::Array> array)
: prologue_behavior_(prologue_behavior), array_(std::move(array)) {}
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::TracedGlobal<v8::Object>* global) {
to_register_with_v8_.push_back(global);
}
bool AdvanceTracing(double deadline_in_ms) final {
for (auto global : to_register_with_v8_) {
RegisterEmbedderReference(global->As<v8::Value>());
}
to_register_with_v8_.clear();
return true;
}
bool IsTracingDone() final { return to_register_with_v8_.empty(); }
void TracePrologue(EmbedderHeapTracer::TraceFlags) final {
if (prologue_behavior_ == TracePrologueBehavior::kCallV8WriteBarrier) {
auto local = array_.Get(isolate());
local->Set(local->CreationContext(), 0, v8::Object::New(isolate()))
.Check();
}
}
void TraceEpilogue() 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;
}
void ConsiderTracedGlobalAsRoot(bool value) {
consider_traced_global_as_root_ = value;
}
bool IsRootForNonTracingGC(const v8::TracedGlobal<v8::Value>& handle) final {
return consider_traced_global_as_root_;
}
private:
std::vector<std::pair<void*, void*>> registered_from_v8_;
std::vector<v8::TracedGlobal<v8::Object>*> to_register_with_v8_;
bool consider_traced_global_as_root_ = true;
TracePrologueBehavior prologue_behavior_ = TracePrologueBehavior::kNoop;
v8::Global<v8::Array> array_;
};
} // 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;
heap::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;
heap::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::TracedGlobal<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);
}
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;
heap::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;
heap::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;
heap::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;
heap::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;
heap::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 {
void ConstructJSObject(v8::Isolate* isolate, v8::Local<v8::Context> context,
v8::TracedGlobal<v8::Object>* global) {
v8::HandleScope scope(isolate);
v8::Local<v8::Object> object(v8::Object::New(isolate));
CHECK(!object.IsEmpty());
*global = v8::TracedGlobal<v8::Object>(isolate, object);
CHECK(!global->IsEmpty());
}
void ConstructJSApiObject(v8::Isolate* isolate, v8::Local<v8::Context> context,
v8::TracedGlobal<v8::Object>* global) {
v8::HandleScope scope(isolate);
v8::Local<v8::Object> object(
ConstructTraceableJSApiObject(context, nullptr, nullptr));
CHECK(!object.IsEmpty());
*global = v8::TracedGlobal<v8::Object>(isolate, object);
CHECK(!global->IsEmpty());
}
enum class SurvivalMode { kSurvives, kDies };
template <typename ModifierFunction, typename ConstructTracedGlobalFunction>
void TracedGlobalTest(v8::Isolate* isolate,
ConstructTracedGlobalFunction construct_function,
ModifierFunction modifier_function, void (*gc_function)(),
SurvivalMode survives) {
v8::HandleScope scope(isolate);
v8::Local<v8::Context> context = v8::Context::New(isolate);
v8::Context::Scope context_scope(context);
v8::TracedGlobal<v8::Object> global;
construct_function(isolate, context, &global);
CHECK(InYoungGeneration(isolate, global));
modifier_function(global);
gc_function();
CHECK_IMPLIES(survives == SurvivalMode::kSurvives, !global.IsEmpty());
CHECK_IMPLIES(survives == SurvivalMode::kDies, global.IsEmpty());
}
} // namespace
TEST(TracedGlobalReset) {
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
v8::TracedGlobal<v8::Object> traced;
ConstructJSObject(isolate, isolate->GetCurrentContext(), &traced);
CHECK(!traced.IsEmpty());
traced.Reset();
CHECK(traced.IsEmpty());
}
TEST(TracedGlobalInStdVector) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
std::vector<v8::TracedGlobal<v8::Object>> vec;
{
v8::HandleScope scope(isolate);
vec.emplace_back(isolate, v8::Object::New(isolate));
}
CHECK(!vec[0].IsEmpty());
InvokeMarkSweep();
CHECK(vec[0].IsEmpty());
}
TEST(TracedGlobalInStdUnorderedMap) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
std::unordered_map<int, v8::TracedGlobal<v8::Object>> map;
{
v8::HandleScope scope(isolate);
map.emplace(std::piecewise_construct, std::forward_as_tuple(1),
std::forward_as_tuple(isolate, v8::Object::New(isolate)));
}
CHECK(!map[1].IsEmpty());
InvokeMarkSweep();
CHECK(map[1].IsEmpty());
}
TEST(TracedGlobalToUnmodifiedJSObjectDiesOnMarkSweep) {
CcTest::InitializeVM();
TracedGlobalTest(
CcTest::isolate(), ConstructJSObject,
[](const TracedGlobal<v8::Object>& global) {}, InvokeMarkSweep,
SurvivalMode::kDies);
}
TEST(TracedGlobalToUnmodifiedJSObjectSurvivesMarkSweepWhenHeldAliveOtherwise) {
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::Global<v8::Object> strong_global;
TracedGlobalTest(
CcTest::isolate(), ConstructJSObject,
[isolate, &strong_global](const TracedGlobal<v8::Object>& global) {
v8::HandleScope scope(isolate);
strong_global = v8::Global<v8::Object>(isolate, global.Get(isolate));
},
InvokeMarkSweep, SurvivalMode::kSurvives);
}
TEST(TracedGlobalToUnmodifiedJSObjectSurvivesScavenge) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
TracedGlobalTest(
CcTest::isolate(), ConstructJSObject,
[](const TracedGlobal<v8::Object>& global) {}, InvokeScavenge,
SurvivalMode::kSurvives);
}
TEST(TracedGlobalToUnmodifiedJSObjectSurvivesScavengeWhenExcludedFromRoots) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
tracer.ConsiderTracedGlobalAsRoot(false);
TracedGlobalTest(
CcTest::isolate(), ConstructJSObject,
[](const TracedGlobal<v8::Object>& global) {}, InvokeScavenge,
SurvivalMode::kSurvives);
}
TEST(TracedGlobalToUnmodifiedJSApiObjectSurvivesScavengePerDefault) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
tracer.ConsiderTracedGlobalAsRoot(true);
TracedGlobalTest(
CcTest::isolate(), ConstructJSApiObject,
[](const TracedGlobal<v8::Object>& global) {}, InvokeScavenge,
SurvivalMode::kSurvives);
}
TEST(TracedGlobalToUnmodifiedJSApiObjectDiesOnScavengeWhenExcludedFromRoots) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
tracer.ConsiderTracedGlobalAsRoot(false);
TracedGlobalTest(
CcTest::isolate(), ConstructJSApiObject,
[](const TracedGlobal<v8::Object>& global) {}, InvokeScavenge,
SurvivalMode::kDies);
}
TEST(TracedGlobalWrapperClassId) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
v8::TracedGlobal<v8::Object> traced;
ConstructJSObject(isolate, isolate->GetCurrentContext(), &traced);
CHECK_EQ(0, traced.WrapperClassId());
traced.SetWrapperClassId(17);
CHECK_EQ(17, traced.WrapperClassId());
}
namespace {
class TracedGlobalVisitor final
: public v8::EmbedderHeapTracer::TracedGlobalHandleVisitor {
public:
~TracedGlobalVisitor() override = default;
void VisitTracedGlobalHandle(const TracedGlobal<Value>& value) final {
if (value.WrapperClassId() == 57) {
count_++;
}
}
size_t count() const { return count_; }
private:
size_t count_ = 0;
};
} // namespace
TEST(TracedGlobalIteration) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
v8::TracedGlobal<v8::Object> traced;
ConstructJSObject(isolate, isolate->GetCurrentContext(), &traced);
CHECK(!traced.IsEmpty());
traced.SetWrapperClassId(57);
TracedGlobalVisitor visitor;
{
v8::HandleScope scope(isolate);
tracer.IterateTracedGlobalHandles(&visitor);
}
CHECK_EQ(1, visitor.count());
}
namespace {
void FinalizationCallback(const WeakCallbackInfo<void>& data) {
v8::TracedGlobal<v8::Object>* traced =
reinterpret_cast<v8::TracedGlobal<v8::Object>*>(data.GetParameter());
CHECK_EQ(reinterpret_cast<void*>(0x4), data.GetInternalField(0));
CHECK_EQ(reinterpret_cast<void*>(0x8), data.GetInternalField(1));
traced->Reset();
}
} // namespace
TEST(TracedGlobalSetFinalizationCallbackScavenge) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
TestEmbedderHeapTracer tracer;
tracer.ConsiderTracedGlobalAsRoot(false);
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
v8::TracedGlobal<v8::Object> traced;
ConstructJSApiObject(isolate, isolate->GetCurrentContext(), &traced);
CHECK(!traced.IsEmpty());
{
v8::HandleScope scope(isolate);
auto local = traced.Get(isolate);
local->SetAlignedPointerInInternalField(0, reinterpret_cast<void*>(0x4));
local->SetAlignedPointerInInternalField(1, reinterpret_cast<void*>(0x8));
}
traced.SetFinalizationCallback(&traced, FinalizationCallback);
heap::InvokeScavenge();
CHECK(traced.IsEmpty());
}
TEST(TracedGlobalSetFinalizationCallbackMarkSweep) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
v8::TracedGlobal<v8::Object> traced;
ConstructJSApiObject(isolate, isolate->GetCurrentContext(), &traced);
CHECK(!traced.IsEmpty());
{
v8::HandleScope scope(isolate);
auto local = traced.Get(isolate);
local->SetAlignedPointerInInternalField(0, reinterpret_cast<void*>(0x4));
local->SetAlignedPointerInInternalField(1, reinterpret_cast<void*>(0x8));
}
traced.SetFinalizationCallback(&traced, FinalizationCallback);
heap::InvokeMarkSweep();
CHECK(traced.IsEmpty());
}
TEST(TracePrologueCallingIntoV8WriteBarrier) {
// Regression test: https://crbug.com/940003
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
v8::Global<v8::Array> global;
{
v8::HandleScope scope(isolate);
auto local = v8::Array::New(isolate, 10);
global.Reset(isolate, local);
}
TestEmbedderHeapTracer tracer(TracePrologueBehavior::kCallV8WriteBarrier,
std::move(global));
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
SimulateIncrementalMarking(CcTest::i_isolate()->heap());
}
namespace {
bool all_zeroes(char* begin, size_t len) {
return std::all_of(begin, begin + len, [](char byte) { return byte == 0; });
}
} // namespace
TEST(TracedGlobalWithDestructor) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
void* first_field = reinterpret_cast<void*>(0x2);
char* memory = new char[sizeof(v8::TracedGlobal<v8::Object>)];
auto* traced = new (memory) v8::TracedGlobal<v8::Object>();
{
v8::HandleScope scope(isolate);
v8::Local<v8::Object> object(ConstructTraceableJSApiObject(
isolate->GetCurrentContext(), first_field, nullptr));
CHECK(traced->IsEmpty());
*traced = v8::TracedGlobal<v8::Object>(isolate, object);
CHECK(!traced->IsEmpty());
}
traced->~TracedGlobal<v8::Object>();
// Note: The following checks refer to the implementation detail that a
// cleared handle is zeroed out.
CHECK(all_zeroes(memory, sizeof(v8::TracedGlobal<v8::Object>)));
heap::InvokeMarkSweep();
CHECK(all_zeroes(memory, sizeof(v8::TracedGlobal<v8::Object>)));
delete[] memory;
}
TEST(TracedGlobalNoDestructor) {
ManualGCScope manual_gc;
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
TestEmbedderHeapTracer tracer;
heap::TemporaryEmbedderHeapTracerScope tracer_scope(isolate, &tracer);
void* first_field = reinterpret_cast<void*>(0x2);
char* memory = new char[sizeof(v8::TracedGlobal<v8::Value>)];
auto* traced = new (memory) v8::TracedGlobal<v8::Value>();
{
v8::HandleScope scope(isolate);
v8::Local<v8::Value> object(ConstructTraceableJSApiObject(
isolate->GetCurrentContext(), first_field, nullptr));
CHECK(traced->IsEmpty());
*traced = v8::TracedGlobal<v8::Value>(isolate, object);
CHECK(!traced->IsEmpty());
}
traced->~TracedGlobal<v8::Value>();
// Note: The following checks refer to the implementation detail that a
// cleared handle is zeroed out.
CHECK(!all_zeroes(memory, sizeof(v8::TracedGlobal<v8::Value>)));
heap::InvokeMarkSweep();
CHECK(all_zeroes(memory, sizeof(v8::TracedGlobal<v8::Value>)));
delete[] memory;
}
} // namespace heap
} // namespace internal
} // namespace v8