text: // Copyright 2012 the V8 project authors. All rights reserved.
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  //       notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  //       copyright notice, this list of conditions and the following
  //       disclaimer in the documentation and/or other materials provided
  //       with the distribution.
  //     * Neither the name of Google Inc. nor the names of its
  //       contributors may be used to endorse or promote products derived
  //       from this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #include <stdlib.h>
  
  #include "v8.h"
  
  #include "compilation-cache.h"
  #include "execution.h"
  #include "factory.h"
  #include "macro-assembler.h"
  #include "global-handles.h"
  #include "stub-cache.h"
  #include "cctest.h"
  
  using namespace v8::internal;
  
  
  // Go through all incremental marking steps in one swoop.
  static void SimulateIncrementalMarking() {
    MarkCompactCollector* collector = HEAP->mark_compact_collector();
    IncrementalMarking* marking = HEAP->incremental_marking();
    if (collector->IsConcurrentSweepingInProgress()) {
      collector->WaitUntilSweepingCompleted();
    }
    CHECK(marking->IsMarking() || marking->IsStopped());
    if (marking->IsStopped()) {
      marking->Start();
    }
    CHECK(marking->IsMarking());
    while (!marking->IsComplete()) {
      marking->Step(MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
    }
    CHECK(marking->IsComplete());
  }
  
  
  static void CheckMap(Map* map, int type, int instance_size) {
    CHECK(map->IsHeapObject());
  #ifdef DEBUG
    CHECK(HEAP->Contains(map));
  #endif
    CHECK_EQ(HEAP->meta_map(), map->map());
    CHECK_EQ(type, map->instance_type());
    CHECK_EQ(instance_size, map->instance_size());
  }
  
  
  TEST(HeapMaps) {
    CcTest::InitializeVM();
    CheckMap(HEAP->meta_map(), MAP_TYPE, Map::kSize);
    CheckMap(HEAP->heap_number_map(), HEAP_NUMBER_TYPE, HeapNumber::kSize);
    CheckMap(HEAP->fixed_array_map(), FIXED_ARRAY_TYPE, kVariableSizeSentinel);
    CheckMap(HEAP->string_map(), STRING_TYPE, kVariableSizeSentinel);
  }
  
  
  static void CheckOddball(Isolate* isolate, Object* obj, const char* string) {
    CHECK(obj->IsOddball());
    bool exc;
    Object* print_string =
        *Execution::ToString(Handle<Object>(obj, isolate), &exc);
    CHECK(String::cast(print_string)->IsUtf8EqualTo(CStrVector(string)));
  }
  
  
  static void CheckSmi(Isolate* isolate, int value, const char* string) {
    bool exc;
    Object* print_string =
        *Execution::ToString(Handle<Object>(Smi::FromInt(value), isolate), &exc);
    CHECK(String::cast(print_string)->IsUtf8EqualTo(CStrVector(string)));
  }
  
  
  static void CheckNumber(Isolate* isolate, double value, const char* string) {
    Object* obj = HEAP->NumberFromDouble(value)->ToObjectChecked();
    CHECK(obj->IsNumber());
    bool exc;
    Object* print_string =
        *Execution::ToString(Handle<Object>(obj, isolate), &exc);
    CHECK(String::cast(print_string)->IsUtf8EqualTo(CStrVector(string)));
  }
  
  
  static void CheckFindCodeObject(Isolate* isolate) {
    // Test FindCodeObject
  #define __ assm.
  
    Assembler assm(isolate, NULL, 0);
  
    __ nop();  // supported on all architectures
  
    CodeDesc desc;
    assm.GetCode(&desc);
    Heap* heap = isolate->heap();
    Object* code = heap->CreateCode(
        desc,
        Code::ComputeFlags(Code::STUB),
        Handle<Code>())->ToObjectChecked();
    CHECK(code->IsCode());
  
    HeapObject* obj = HeapObject::cast(code);
    Address obj_addr = obj->address();
  
    for (int i = 0; i < obj->Size(); i += kPointerSize) {
      Object* found = isolate->FindCodeObject(obj_addr + i);
      CHECK_EQ(code, found);
    }
  
    Object* copy = heap->CreateCode(
        desc,
        Code::ComputeFlags(Code::STUB),
        Handle<Code>())->ToObjectChecked();
    CHECK(copy->IsCode());
    HeapObject* obj_copy = HeapObject::cast(copy);
    Object* not_right = isolate->FindCodeObject(obj_copy->address() +
                                                obj_copy->Size() / 2);
    CHECK(not_right != code);
  }
  
  
  TEST(HeapObjects) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    Heap* heap = isolate->heap();
  
    HandleScope sc(isolate);
    Object* value = heap->NumberFromDouble(1.000123)->ToObjectChecked();
    CHECK(value->IsHeapNumber());
    CHECK(value->IsNumber());
    CHECK_EQ(1.000123, value->Number());
  
    value = heap->NumberFromDouble(1.0)->ToObjectChecked();
    CHECK(value->IsSmi());
    CHECK(value->IsNumber());
    CHECK_EQ(1.0, value->Number());
  
    value = heap->NumberFromInt32(1024)->ToObjectChecked();
    CHECK(value->IsSmi());
    CHECK(value->IsNumber());
    CHECK_EQ(1024.0, value->Number());
  
    value = heap->NumberFromInt32(Smi::kMinValue)->ToObjectChecked();
    CHECK(value->IsSmi());
    CHECK(value->IsNumber());
    CHECK_EQ(Smi::kMinValue, Smi::cast(value)->value());
  
    value = heap->NumberFromInt32(Smi::kMaxValue)->ToObjectChecked();
    CHECK(value->IsSmi());
    CHECK(value->IsNumber());
    CHECK_EQ(Smi::kMaxValue, Smi::cast(value)->value());
  
  #ifndef V8_TARGET_ARCH_X64
    // TODO(lrn): We need a NumberFromIntptr function in order to test this.
    value = heap->NumberFromInt32(Smi::kMinValue - 1)->ToObjectChecked();
    CHECK(value->IsHeapNumber());
    CHECK(value->IsNumber());
    CHECK_EQ(static_cast<double>(Smi::kMinValue - 1), value->Number());
  #endif
  
    MaybeObject* maybe_value =
        heap->NumberFromUint32(static_cast<uint32_t>(Smi::kMaxValue) + 1);
    value = maybe_value->ToObjectChecked();
    CHECK(value->IsHeapNumber());
    CHECK(value->IsNumber());
    CHECK_EQ(static_cast<double>(static_cast<uint32_t>(Smi::kMaxValue) + 1),
             value->Number());
  
    maybe_value = heap->NumberFromUint32(static_cast<uint32_t>(1) << 31);
    value = maybe_value->ToObjectChecked();
    CHECK(value->IsHeapNumber());
    CHECK(value->IsNumber());
    CHECK_EQ(static_cast<double>(static_cast<uint32_t>(1) << 31),
             value->Number());
  
    // nan oddball checks
    CHECK(heap->nan_value()->IsNumber());
    CHECK(std::isnan(heap->nan_value()->Number()));
  
    Handle<String> s = factory->NewStringFromAscii(CStrVector("fisk hest "));
    CHECK(s->IsString());
    CHECK_EQ(10, s->length());
  
    String* object_string = String::cast(heap->Object_string());
    CHECK(
        Isolate::Current()->context()->global_object()->HasLocalProperty(
            object_string));
  
    // Check ToString for oddballs
    CheckOddball(isolate, heap->true_value(), "true");
    CheckOddball(isolate, heap->false_value(), "false");
    CheckOddball(isolate, heap->null_value(), "null");
    CheckOddball(isolate, heap->undefined_value(), "undefined");
  
    // Check ToString for Smis
    CheckSmi(isolate, 0, "0");
    CheckSmi(isolate, 42, "42");
    CheckSmi(isolate, -42, "-42");
  
    // Check ToString for Numbers
    CheckNumber(isolate, 1.1, "1.1");
  
    CheckFindCodeObject(isolate);
  }
  
  
  TEST(Tagging) {
    CcTest::InitializeVM();
    int request = 24;
    CHECK_EQ(request, static_cast<int>(OBJECT_POINTER_ALIGN(request)));
    CHECK(Smi::FromInt(42)->IsSmi());
    CHECK(Failure::RetryAfterGC(NEW_SPACE)->IsFailure());
    CHECK_EQ(NEW_SPACE,
             Failure::RetryAfterGC(NEW_SPACE)->allocation_space());
    CHECK_EQ(OLD_POINTER_SPACE,
             Failure::RetryAfterGC(OLD_POINTER_SPACE)->allocation_space());
    CHECK(Failure::Exception()->IsFailure());
    CHECK(Smi::FromInt(Smi::kMinValue)->IsSmi());
    CHECK(Smi::FromInt(Smi::kMaxValue)->IsSmi());
  }
  
  
  TEST(GarbageCollection) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    Factory* factory = isolate->factory();
  
    HandleScope sc(isolate);
    // Check GC.
    heap->CollectGarbage(NEW_SPACE);
  
    Handle<String> name = factory->InternalizeUtf8String("theFunction");
    Handle<String> prop_name = factory->InternalizeUtf8String("theSlot");
    Handle<String> prop_namex = factory->InternalizeUtf8String("theSlotx");
    Handle<String> obj_name = factory->InternalizeUtf8String("theObject");
  
    {
      HandleScope inner_scope(isolate);
      // Allocate a function and keep it in global object's property.
      Handle<JSFunction> function =
          factory->NewFunction(name, factory->undefined_value());
      Handle<Map> initial_map =
          factory->NewMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
      function->set_initial_map(*initial_map);
      Isolate::Current()->context()->global_object()->SetProperty(
          *name, *function, NONE, kNonStrictMode)->ToObjectChecked();
      // Allocate an object.  Unrooted after leaving the scope.
      Handle<JSObject> obj = factory->NewJSObject(function);
      obj->SetProperty(
          *prop_name, Smi::FromInt(23), NONE, kNonStrictMode)->ToObjectChecked();
      obj->SetProperty(
          *prop_namex, Smi::FromInt(24), NONE, kNonStrictMode)->ToObjectChecked();
  
      CHECK_EQ(Smi::FromInt(23), obj->GetProperty(*prop_name));
      CHECK_EQ(Smi::FromInt(24), obj->GetProperty(*prop_namex));
    }
  
    heap->CollectGarbage(NEW_SPACE);
  
    // Function should be alive.
    CHECK(Isolate::Current()->context()->global_object()->
          HasLocalProperty(*name));
    // Check function is retained.
    Object* func_value = Isolate::Current()->context()->global_object()->
        GetProperty(*name)->ToObjectChecked();
    CHECK(func_value->IsJSFunction());
    Handle<JSFunction> function(JSFunction::cast(func_value));
  
    {
      HandleScope inner_scope(isolate);
      // Allocate another object, make it reachable from global.
      Handle<JSObject> obj = factory->NewJSObject(function);
      Isolate::Current()->context()->global_object()->SetProperty(
          *obj_name, *obj, NONE, kNonStrictMode)->ToObjectChecked();
      obj->SetProperty(
          *prop_name, Smi::FromInt(23), NONE, kNonStrictMode)->ToObjectChecked();
    }
  
    // After gc, it should survive.
    heap->CollectGarbage(NEW_SPACE);
  
    CHECK(Isolate::Current()->context()->global_object()->
          HasLocalProperty(*obj_name));
    CHECK(Isolate::Current()->context()->global_object()->
          GetProperty(*obj_name)->ToObjectChecked()->IsJSObject());
    Object* obj = Isolate::Current()->context()->global_object()->
        GetProperty(*obj_name)->ToObjectChecked();
    JSObject* js_obj = JSObject::cast(obj);
    CHECK_EQ(Smi::FromInt(23), js_obj->GetProperty(*prop_name));
  }
  
  
  static void VerifyStringAllocation(Isolate* isolate, const char* string) {
    HandleScope scope(isolate);
    Handle<String> s = isolate->factory()->NewStringFromUtf8(CStrVector(string));
    CHECK_EQ(StrLength(string), s->length());
    for (int index = 0; index < s->length(); index++) {
      CHECK_EQ(static_cast<uint16_t>(string[index]), s->Get(index));
    }
  }
  
  
  TEST(String) {
    CcTest::InitializeVM();
    Isolate* isolate = reinterpret_cast<Isolate*>(CcTest::isolate());
  
    VerifyStringAllocation(isolate, "a");
    VerifyStringAllocation(isolate, "ab");
    VerifyStringAllocation(isolate, "abc");
    VerifyStringAllocation(isolate, "abcd");
    VerifyStringAllocation(isolate, "fiskerdrengen er paa havet");
  }
  
  
  TEST(LocalHandles) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    v8::HandleScope scope(CcTest::isolate());
    const char* name = "Kasper the spunky";
    Handle<String> string = factory->NewStringFromAscii(CStrVector(name));
    CHECK_EQ(StrLength(name), string->length());
  }
  
  
  TEST(GlobalHandles) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    Factory* factory = isolate->factory();
    GlobalHandles* global_handles = isolate->global_handles();
  
    Handle<Object> h1;
    Handle<Object> h2;
    Handle<Object> h3;
    Handle<Object> h4;
  
    {
      HandleScope scope(isolate);
  
      Handle<Object> i = factory->NewStringFromAscii(CStrVector("fisk"));
      Handle<Object> u = factory->NewNumber(1.12344);
  
      h1 = global_handles->Create(*i);
      h2 = global_handles->Create(*u);
      h3 = global_handles->Create(*i);
      h4 = global_handles->Create(*u);
    }
  
    // after gc, it should survive
    heap->CollectGarbage(NEW_SPACE);
  
    CHECK((*h1)->IsString());
    CHECK((*h2)->IsHeapNumber());
    CHECK((*h3)->IsString());
    CHECK((*h4)->IsHeapNumber());
  
    CHECK_EQ(*h3, *h1);
    global_handles->Destroy(h1.location());
    global_handles->Destroy(h3.location());
  
    CHECK_EQ(*h4, *h2);
    global_handles->Destroy(h2.location());
    global_handles->Destroy(h4.location());
  }
  
  
  static bool WeakPointerCleared = false;
  
  static void TestWeakGlobalHandleCallback(v8::Isolate* isolate,
                                           v8::Persistent<v8::Value>* handle,
                                           void* id) {
    if (1234 == reinterpret_cast<intptr_t>(id)) WeakPointerCleared = true;
    handle->Dispose(isolate);
  }
  
  
  TEST(WeakGlobalHandlesScavenge) {
    i::FLAG_stress_compaction = false;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    Factory* factory = isolate->factory();
    GlobalHandles* global_handles = isolate->global_handles();
  
    WeakPointerCleared = false;
  
    Handle<Object> h1;
    Handle<Object> h2;
  
    {
      HandleScope scope(isolate);
  
      Handle<Object> i = factory->NewStringFromAscii(CStrVector("fisk"));
      Handle<Object> u = factory->NewNumber(1.12344);
  
      h1 = global_handles->Create(*i);
      h2 = global_handles->Create(*u);
    }
  
    global_handles->MakeWeak(h2.location(),
                             reinterpret_cast<void*>(1234),
                             &TestWeakGlobalHandleCallback);
  
    // Scavenge treats weak pointers as normal roots.
    heap->PerformScavenge();
  
    CHECK((*h1)->IsString());
    CHECK((*h2)->IsHeapNumber());
  
    CHECK(!WeakPointerCleared);
    CHECK(!global_handles->IsNearDeath(h2.location()));
    CHECK(!global_handles->IsNearDeath(h1.location()));
  
    global_handles->Destroy(h1.location());
    global_handles->Destroy(h2.location());
  }
  
  
  TEST(WeakGlobalHandlesMark) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    Factory* factory = isolate->factory();
    GlobalHandles* global_handles = isolate->global_handles();
  
    WeakPointerCleared = false;
  
    Handle<Object> h1;
    Handle<Object> h2;
  
    {
      HandleScope scope(isolate);
  
      Handle<Object> i = factory->NewStringFromAscii(CStrVector("fisk"));
      Handle<Object> u = factory->NewNumber(1.12344);
  
      h1 = global_handles->Create(*i);
      h2 = global_handles->Create(*u);
    }
  
    // Make sure the objects are promoted.
    heap->CollectGarbage(OLD_POINTER_SPACE);
    heap->CollectGarbage(NEW_SPACE);
    CHECK(!heap->InNewSpace(*h1) && !heap->InNewSpace(*h2));
  
    global_handles->MakeWeak(h2.location(),
                             reinterpret_cast<void*>(1234),
                             &TestWeakGlobalHandleCallback);
    CHECK(!GlobalHandles::IsNearDeath(h1.location()));
    CHECK(!GlobalHandles::IsNearDeath(h2.location()));
  
    // Incremental marking potentially marked handles before they turned weak.
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
  
    CHECK((*h1)->IsString());
  
    CHECK(WeakPointerCleared);
    CHECK(!GlobalHandles::IsNearDeath(h1.location()));
  
    global_handles->Destroy(h1.location());
  }
  
  
  TEST(DeleteWeakGlobalHandle) {
    i::FLAG_stress_compaction = false;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    Factory* factory = isolate->factory();
    GlobalHandles* global_handles = isolate->global_handles();
  
    WeakPointerCleared = false;
  
    Handle<Object> h;
  
    {
      HandleScope scope(isolate);
  
      Handle<Object> i = factory->NewStringFromAscii(CStrVector("fisk"));
      h = global_handles->Create(*i);
    }
  
    global_handles->MakeWeak(h.location(),
                             reinterpret_cast<void*>(1234),
                             &TestWeakGlobalHandleCallback);
  
    // Scanvenge does not recognize weak reference.
    heap->PerformScavenge();
  
    CHECK(!WeakPointerCleared);
  
    // Mark-compact treats weak reference properly.
    heap->CollectGarbage(OLD_POINTER_SPACE);
  
    CHECK(WeakPointerCleared);
  }
  
  
  static const char* not_so_random_string_table[] = {
    "abstract",
    "boolean",
    "break",
    "byte",
    "case",
    "catch",
    "char",
    "class",
    "const",
    "continue",
    "debugger",
    "default",
    "delete",
    "do",
    "double",
    "else",
    "enum",
    "export",
    "extends",
    "false",
    "final",
    "finally",
    "float",
    "for",
    "function",
    "goto",
    "if",
    "implements",
    "import",
    "in",
    "instanceof",
    "int",
    "interface",
    "long",
    "native",
    "new",
    "null",
    "package",
    "private",
    "protected",
    "public",
    "return",
    "short",
    "static",
    "super",
    "switch",
    "synchronized",
    "this",
    "throw",
    "throws",
    "transient",
    "true",
    "try",
    "typeof",
    "var",
    "void",
    "volatile",
    "while",
    "with",
    0
  };
  
  
  static void CheckInternalizedStrings(const char** strings) {
    for (const char* string = *strings; *strings != 0; string = *strings++) {
      Object* a;
      MaybeObject* maybe_a = HEAP->InternalizeUtf8String(string);
      // InternalizeUtf8String may return a failure if a GC is needed.
      if (!maybe_a->ToObject(&a)) continue;
      CHECK(a->IsInternalizedString());
      Object* b;
      MaybeObject* maybe_b = HEAP->InternalizeUtf8String(string);
      if (!maybe_b->ToObject(&b)) continue;
      CHECK_EQ(b, a);
      CHECK(String::cast(b)->IsUtf8EqualTo(CStrVector(string)));
    }
  }
  
  
  TEST(StringTable) {
    CcTest::InitializeVM();
  
    CheckInternalizedStrings(not_so_random_string_table);
    CheckInternalizedStrings(not_so_random_string_table);
  }
  
  
  TEST(FunctionAllocation) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    v8::HandleScope sc(CcTest::isolate());
    Handle<String> name = factory->InternalizeUtf8String("theFunction");
    Handle<JSFunction> function =
        factory->NewFunction(name, factory->undefined_value());
    Handle<Map> initial_map =
        factory->NewMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
    function->set_initial_map(*initial_map);
  
    Handle<String> prop_name = factory->InternalizeUtf8String("theSlot");
    Handle<JSObject> obj = factory->NewJSObject(function);
    obj->SetProperty(
        *prop_name, Smi::FromInt(23), NONE, kNonStrictMode)->ToObjectChecked();
    CHECK_EQ(Smi::FromInt(23), obj->GetProperty(*prop_name));
    // Check that we can add properties to function objects.
    function->SetProperty(
        *prop_name, Smi::FromInt(24), NONE, kNonStrictMode)->ToObjectChecked();
    CHECK_EQ(Smi::FromInt(24), function->GetProperty(*prop_name));
  }
  
  
  TEST(ObjectProperties) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    v8::HandleScope sc(CcTest::isolate());
    String* object_string = String::cast(HEAP->Object_string());
    Object* raw_object = Isolate::Current()->context()->global_object()->
        GetProperty(object_string)->ToObjectChecked();
    JSFunction* object_function = JSFunction::cast(raw_object);
    Handle<JSFunction> constructor(object_function);
    Handle<JSObject> obj = factory->NewJSObject(constructor);
    Handle<String> first = factory->InternalizeUtf8String("first");
    Handle<String> second = factory->InternalizeUtf8String("second");
  
    // check for empty
    CHECK(!obj->HasLocalProperty(*first));
  
    // add first
    obj->SetProperty(
        *first, Smi::FromInt(1), NONE, kNonStrictMode)->ToObjectChecked();
    CHECK(obj->HasLocalProperty(*first));
  
    // delete first
    JSReceiver::DeleteProperty(obj, first, JSReceiver::NORMAL_DELETION);
    CHECK(!obj->HasLocalProperty(*first));
  
    // add first and then second
    obj->SetProperty(
        *first, Smi::FromInt(1), NONE, kNonStrictMode)->ToObjectChecked();
    obj->SetProperty(
        *second, Smi::FromInt(2), NONE, kNonStrictMode)->ToObjectChecked();
    CHECK(obj->HasLocalProperty(*first));
    CHECK(obj->HasLocalProperty(*second));
  
    // delete first and then second
    JSReceiver::DeleteProperty(obj, first, JSReceiver::NORMAL_DELETION);
    CHECK(obj->HasLocalProperty(*second));
    JSReceiver::DeleteProperty(obj, second, JSReceiver::NORMAL_DELETION);
    CHECK(!obj->HasLocalProperty(*first));
    CHECK(!obj->HasLocalProperty(*second));
  
    // add first and then second
    obj->SetProperty(
        *first, Smi::FromInt(1), NONE, kNonStrictMode)->ToObjectChecked();
    obj->SetProperty(
        *second, Smi::FromInt(2), NONE, kNonStrictMode)->ToObjectChecked();
    CHECK(obj->HasLocalProperty(*first));
    CHECK(obj->HasLocalProperty(*second));
  
    // delete second and then first
    JSReceiver::DeleteProperty(obj, second, JSReceiver::NORMAL_DELETION);
    CHECK(obj->HasLocalProperty(*first));
    JSReceiver::DeleteProperty(obj, first, JSReceiver::NORMAL_DELETION);
    CHECK(!obj->HasLocalProperty(*first));
    CHECK(!obj->HasLocalProperty(*second));
  
    // check string and internalized string match
    const char* string1 = "fisk";
    Handle<String> s1 = factory->NewStringFromAscii(CStrVector(string1));
    obj->SetProperty(
        *s1, Smi::FromInt(1), NONE, kNonStrictMode)->ToObjectChecked();
    Handle<String> s1_string = factory->InternalizeUtf8String(string1);
    CHECK(obj->HasLocalProperty(*s1_string));
  
    // check internalized string and string match
    const char* string2 = "fugl";
    Handle<String> s2_string = factory->InternalizeUtf8String(string2);
    obj->SetProperty(
        *s2_string, Smi::FromInt(1), NONE, kNonStrictMode)->ToObjectChecked();
    Handle<String> s2 = factory->NewStringFromAscii(CStrVector(string2));
    CHECK(obj->HasLocalProperty(*s2));
  }
  
  
  TEST(JSObjectMaps) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    v8::HandleScope sc(CcTest::isolate());
    Handle<String> name = factory->InternalizeUtf8String("theFunction");
    Handle<JSFunction> function =
        factory->NewFunction(name, factory->undefined_value());
    Handle<Map> initial_map =
        factory->NewMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
    function->set_initial_map(*initial_map);
  
    Handle<String> prop_name = factory->InternalizeUtf8String("theSlot");
    Handle<JSObject> obj = factory->NewJSObject(function);
  
    // Set a propery
    obj->SetProperty(
        *prop_name, Smi::FromInt(23), NONE, kNonStrictMode)->ToObjectChecked();
    CHECK_EQ(Smi::FromInt(23), obj->GetProperty(*prop_name));
  
    // Check the map has changed
    CHECK(*initial_map != obj->map());
  }
  
  
  TEST(JSArray) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    v8::HandleScope sc(CcTest::isolate());
    Handle<String> name = factory->InternalizeUtf8String("Array");
    Object* raw_object = Isolate::Current()->context()->global_object()->
        GetProperty(*name)->ToObjectChecked();
    Handle<JSFunction> function = Handle<JSFunction>(
        JSFunction::cast(raw_object));
  
    // Allocate the object.
    Handle<JSObject> object = factory->NewJSObject(function);
    Handle<JSArray> array = Handle<JSArray>::cast(object);
    // We just initialized the VM, no heap allocation failure yet.
    array->Initialize(0)->ToObjectChecked();
  
    // Set array length to 0.
    array->SetElementsLength(Smi::FromInt(0))->ToObjectChecked();
    CHECK_EQ(Smi::FromInt(0), array->length());
    // Must be in fast mode.
    CHECK(array->HasFastSmiOrObjectElements());
  
    // array[length] = name.
    array->SetElement(0, *name, NONE, kNonStrictMode)->ToObjectChecked();
    CHECK_EQ(Smi::FromInt(1), array->length());
    CHECK_EQ(array->GetElement(0), *name);
  
    // Set array length with larger than smi value.
    Handle<Object> length =
        factory->NewNumberFromUint(static_cast<uint32_t>(Smi::kMaxValue) + 1);
    array->SetElementsLength(*length)->ToObjectChecked();
  
    uint32_t int_length = 0;
    CHECK(length->ToArrayIndex(&int_length));
    CHECK_EQ(*length, array->length());
    CHECK(array->HasDictionaryElements());  // Must be in slow mode.
  
    // array[length] = name.
    array->SetElement(int_length, *name, NONE, kNonStrictMode)->ToObjectChecked();
    uint32_t new_int_length = 0;
    CHECK(array->length()->ToArrayIndex(&new_int_length));
    CHECK_EQ(static_cast<double>(int_length), new_int_length - 1);
    CHECK_EQ(array->GetElement(int_length), *name);
    CHECK_EQ(array->GetElement(0), *name);
  }
  
  
  TEST(JSObjectCopy) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    v8::HandleScope sc(CcTest::isolate());
    String* object_string = String::cast(HEAP->Object_string());
    Object* raw_object = Isolate::Current()->context()->global_object()->
        GetProperty(object_string)->ToObjectChecked();
    JSFunction* object_function = JSFunction::cast(raw_object);
    Handle<JSFunction> constructor(object_function);
    Handle<JSObject> obj = factory->NewJSObject(constructor);
    Handle<String> first = factory->InternalizeUtf8String("first");
    Handle<String> second = factory->InternalizeUtf8String("second");
  
    obj->SetProperty(
        *first, Smi::FromInt(1), NONE, kNonStrictMode)->ToObjectChecked();
    obj->SetProperty(
        *second, Smi::FromInt(2), NONE, kNonStrictMode)->ToObjectChecked();
  
    obj->SetElement(0, *first, NONE, kNonStrictMode)->ToObjectChecked();
    obj->SetElement(1, *second, NONE, kNonStrictMode)->ToObjectChecked();
  
    // Make the clone.
    Handle<JSObject> clone = Copy(obj);
    CHECK(!clone.is_identical_to(obj));
  
    CHECK_EQ(obj->GetElement(0), clone->GetElement(0));
    CHECK_EQ(obj->GetElement(1), clone->GetElement(1));
  
    CHECK_EQ(obj->GetProperty(*first), clone->GetProperty(*first));
    CHECK_EQ(obj->GetProperty(*second), clone->GetProperty(*second));
  
    // Flip the values.
    clone->SetProperty(
        *first, Smi::FromInt(2), NONE, kNonStrictMode)->ToObjectChecked();
    clone->SetProperty(
        *second, Smi::FromInt(1), NONE, kNonStrictMode)->ToObjectChecked();
  
    clone->SetElement(0, *second, NONE, kNonStrictMode)->ToObjectChecked();
    clone->SetElement(1, *first, NONE, kNonStrictMode)->ToObjectChecked();
  
    CHECK_EQ(obj->GetElement(1), clone->GetElement(0));
    CHECK_EQ(obj->GetElement(0), clone->GetElement(1));
  
    CHECK_EQ(obj->GetProperty(*second), clone->GetProperty(*first));
    CHECK_EQ(obj->GetProperty(*first), clone->GetProperty(*second));
  }
  
  
  TEST(StringAllocation) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    const unsigned char chars[] = { 0xe5, 0xa4, 0xa7 };
    for (int length = 0; length < 100; length++) {
      v8::HandleScope scope(CcTest::isolate());
      char* non_ascii = NewArray<char>(3 * length + 1);
      char* ascii = NewArray<char>(length + 1);
      non_ascii[3 * length] = 0;
      ascii[length] = 0;
      for (int i = 0; i < length; i++) {
        ascii[i] = 'a';
        non_ascii[3 * i] = chars[0];
        non_ascii[3 * i + 1] = chars[1];
        non_ascii[3 * i + 2] = chars[2];
      }
      Handle<String> non_ascii_sym =
          factory->InternalizeUtf8String(
              Vector<const char>(non_ascii, 3 * length));
      CHECK_EQ(length, non_ascii_sym->length());
      Handle<String> ascii_sym =
          factory->InternalizeOneByteString(OneByteVector(ascii, length));
      CHECK_EQ(length, ascii_sym->length());
      Handle<String> non_ascii_str =
          factory->NewStringFromUtf8(Vector<const char>(non_ascii, 3 * length));
      non_ascii_str->Hash();
      CHECK_EQ(length, non_ascii_str->length());
      Handle<String> ascii_str =
          factory->NewStringFromUtf8(Vector<const char>(ascii, length));
      ascii_str->Hash();
      CHECK_EQ(length, ascii_str->length());
      DeleteArray(non_ascii);
      DeleteArray(ascii);
    }
  }
  
  
  static int ObjectsFoundInHeap(Heap* heap, Handle<Object> objs[], int size) {
    // Count the number of objects found in the heap.
    int found_count = 0;
    heap->EnsureHeapIsIterable();
    HeapIterator iterator(heap);
    for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next()) {
      for (int i = 0; i < size; i++) {
        if (*objs[i] == obj) {
          found_count++;
        }
      }
    }
    return found_count;
  }
  
  
  TEST(Iteration) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
  
    // Array of objects to scan haep for.
    const int objs_count = 6;
    Handle<Object> objs[objs_count];
    int next_objs_index = 0;
  
    // Allocate a JS array to OLD_POINTER_SPACE and NEW_SPACE
    objs[next_objs_index++] = factory->NewJSArray(10);
    objs[next_objs_index++] = factory->NewJSArray(10,
                                                  FAST_HOLEY_ELEMENTS,
                                                  TENURED);
  
    // Allocate a small string to OLD_DATA_SPACE and NEW_SPACE
    objs[next_objs_index++] =
        factory->NewStringFromAscii(CStrVector("abcdefghij"));
    objs[next_objs_index++] =
        factory->NewStringFromAscii(CStrVector("abcdefghij"), TENURED);
  
    // Allocate a large string (for large object space).
    int large_size = Page::kMaxNonCodeHeapObjectSize + 1;
    char* str = new char[large_size];
    for (int i = 0; i < large_size - 1; ++i) str[i] = 'a';
    str[large_size - 1] = '\0';
    objs[next_objs_index++] =
        factory->NewStringFromAscii(CStrVector(str), TENURED);
    delete[] str;
  
    // Add a Map object to look for.
    objs[next_objs_index++] = Handle<Map>(HeapObject::cast(*objs[0])->map());
  
    CHECK_EQ(objs_count, next_objs_index);
    CHECK_EQ(objs_count, ObjectsFoundInHeap(HEAP, objs, objs_count));
  }
  
  
  TEST(EmptyHandleEscapeFrom) {
    CcTest::InitializeVM();
  
    v8::HandleScope scope(CcTest::isolate());
    Handle<JSObject> runaway;
  
    {
        v8::HandleScope nested(CcTest::isolate());
        Handle<JSObject> empty;
        runaway = empty.EscapeFrom(&nested);
    }
  
    CHECK(runaway.is_null());
  }
  
  
  static int LenFromSize(int size) {
    return (size - FixedArray::kHeaderSize) / kPointerSize;
  }
  
  
  TEST(Regression39128) {
    // Test case for crbug.com/39128.
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
  
    // Increase the chance of 'bump-the-pointer' allocation in old space.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    v8::HandleScope scope(CcTest::isolate());
  
    // The plan: create JSObject which references objects in new space.
    // Then clone this object (forcing it to go into old space) and check
    // that region dirty marks are updated correctly.
  
    // Step 1: prepare a map for the object.  We add 1 inobject property to it.
    Handle<JSFunction> object_ctor(
        Isolate::Current()->native_context()->object_function());
    CHECK(object_ctor->has_initial_map());
    Handle<Map> object_map(object_ctor->initial_map());
    // Create a map with single inobject property.
    Handle<Map> my_map = factory->CopyMap(object_map, 1);
    int n_properties = my_map->inobject_properties();
    CHECK_GT(n_properties, 0);
  
    int object_size = my_map->instance_size();
  
    // Step 2: allocate a lot of objects so to almost fill new space: we need
    // just enough room to allocate JSObject and thus fill the newspace.
  
    int allocation_amount = Min(FixedArray::kMaxSize,
                                HEAP->MaxObjectSizeInNewSpace());
    int allocation_len = LenFromSize(allocation_amount);
    NewSpace* new_space = HEAP->new_space();
    Address* top_addr = new_space->allocation_top_address();
    Address* limit_addr = new_space->allocation_limit_address();
    while ((*limit_addr - *top_addr) > allocation_amount) {
      CHECK(!HEAP->always_allocate());
      Object* array = HEAP->AllocateFixedArray(allocation_len)->ToObjectChecked();
      CHECK(!array->IsFailure());
      CHECK(new_space->Contains(array));
    }
  
    // Step 3: now allocate fixed array and JSObject to fill the whole new space.
    int to_fill = static_cast<int>(*limit_addr - *top_addr - object_size);
    int fixed_array_len = LenFromSize(to_fill);
    CHECK(fixed_array_len < FixedArray::kMaxLength);
  
    CHECK(!HEAP->always_allocate());
    Object* array = HEAP->AllocateFixedArray(fixed_array_len)->ToObjectChecked();
    CHECK(!array->IsFailure());
    CHECK(new_space->Contains(array));
  
    Object* object = HEAP->AllocateJSObjectFromMap(*my_map)->ToObjectChecked();
    CHECK(new_space->Contains(object));
    JSObject* jsobject = JSObject::cast(object);
    CHECK_EQ(0, FixedArray::cast(jsobject->elements())->length());
    CHECK_EQ(0, jsobject->properties()->length());
    // Create a reference to object in new space in jsobject.
    jsobject->FastPropertyAtPut(-1, array);
  
    CHECK_EQ(0, static_cast<int>(*limit_addr - *top_addr));
  
    // Step 4: clone jsobject, but force always allocate first to create a clone
    // in old pointer space.
    Address old_pointer_space_top = HEAP->old_pointer_space()->top();
    AlwaysAllocateScope aa_scope;
    Object* clone_obj = HEAP->CopyJSObject(jsobject)->ToObjectChecked();
    JSObject* clone = JSObject::cast(clone_obj);
    if (clone->address() != old_pointer_space_top) {
      // Alas, got allocated from free list, we cannot do checks.
      return;
    }
    CHECK(HEAP->old_pointer_space()->Contains(clone->address()));
  }
  
  
  TEST(TestCodeFlushing) {
    // If we do not flush code this test is invalid.
    if (!FLAG_flush_code) return;
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
    const char* source = "function foo() {"
                         "  var x = 42;"
                         "  var y = 42;"
                         "  var z = x + y;"
                         "};"
                         "foo()";
    Handle<String> foo_name = factory->InternalizeUtf8String("foo");
  
    // This compile will add the code to the compilation cache.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun(source);
    }
  
    // Check function is compiled.
    Object* func_value = Isolate::Current()->context()->global_object()->
        GetProperty(*foo_name)->ToObjectChecked();
    CHECK(func_value->IsJSFunction());
    Handle<JSFunction> function(JSFunction::cast(func_value));
    CHECK(function->shared()->is_compiled());
  
    // The code will survive at least two GCs.
    HEAP->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    HEAP->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    CHECK(function->shared()->is_compiled());
  
    // Simulate several GCs that use full marking.
    const int kAgingThreshold = 6;
    for (int i = 0; i < kAgingThreshold; i++) {
      HEAP->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    }
  
    // foo should no longer be in the compilation cache
    CHECK(!function->shared()->is_compiled() || function->IsOptimized());
    CHECK(!function->is_compiled() || function->IsOptimized());
    // Call foo to get it recompiled.
    CompileRun("foo()");
    CHECK(function->shared()->is_compiled());
    CHECK(function->is_compiled());
  }
  
  
  TEST(TestCodeFlushingIncremental) {
    // If we do not flush code this test is invalid.
    if (!FLAG_flush_code || !FLAG_flush_code_incrementally) return;
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
    const char* source = "function foo() {"
                         "  var x = 42;"
                         "  var y = 42;"
                         "  var z = x + y;"
                         "};"
                         "foo()";
    Handle<String> foo_name = factory->InternalizeUtf8String("foo");
  
    // This compile will add the code to the compilation cache.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun(source);
    }
  
    // Check function is compiled.
    Object* func_value = Isolate::Current()->context()->global_object()->
        GetProperty(*foo_name)->ToObjectChecked();
    CHECK(func_value->IsJSFunction());
    Handle<JSFunction> function(JSFunction::cast(func_value));
    CHECK(function->shared()->is_compiled());
  
    // The code will survive at least two GCs.
    HEAP->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    HEAP->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    CHECK(function->shared()->is_compiled());
  
    // Simulate several GCs that use incremental marking.
    const int kAgingThreshold = 6;
    for (int i = 0; i < kAgingThreshold; i++) {
      SimulateIncrementalMarking();
      HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    }
    CHECK(!function->shared()->is_compiled() || function->IsOptimized());
    CHECK(!function->is_compiled() || function->IsOptimized());
  
    // This compile will compile the function again.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun("foo();");
    }
  
    // Simulate several GCs that use incremental marking but make sure
    // the loop breaks once the function is enqueued as a candidate.
    for (int i = 0; i < kAgingThreshold; i++) {
      SimulateIncrementalMarking();
      if (!function->next_function_link()->IsUndefined()) break;
      HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    }
  
    // Force optimization while incremental marking is active and while
    // the function is enqueued as a candidate.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun("%OptimizeFunctionOnNextCall(foo); foo();");
    }
  
    // Simulate one final GC to make sure the candidate queue is sane.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    CHECK(function->shared()->is_compiled() || !function->IsOptimized());
    CHECK(function->is_compiled() || !function->IsOptimized());
  }
  
  
  TEST(TestCodeFlushingIncrementalScavenge) {
    // If we do not flush code this test is invalid.
    if (!FLAG_flush_code || !FLAG_flush_code_incrementally) return;
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
    const char* source = "var foo = function() {"
                         "  var x = 42;"
                         "  var y = 42;"
                         "  var z = x + y;"
                         "};"
                         "foo();"
                         "var bar = function() {"
                         "  var x = 23;"
                         "};"
                         "bar();";
    Handle<String> foo_name = factory->InternalizeUtf8String("foo");
    Handle<String> bar_name = factory->InternalizeUtf8String("bar");
  
    // Perfrom one initial GC to enable code flushing.
    HEAP->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
  
    // This compile will add the code to the compilation cache.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun(source);
    }
  
    // Check functions are compiled.
    Object* func_value = Isolate::Current()->context()->global_object()->
        GetProperty(*foo_name)->ToObjectChecked();
    CHECK(func_value->IsJSFunction());
    Handle<JSFunction> function(JSFunction::cast(func_value));
    CHECK(function->shared()->is_compiled());
    Object* func_value2 = Isolate::Current()->context()->global_object()->
        GetProperty(*bar_name)->ToObjectChecked();
    CHECK(func_value2->IsJSFunction());
    Handle<JSFunction> function2(JSFunction::cast(func_value2));
    CHECK(function2->shared()->is_compiled());
  
    // Clear references to functions so that one of them can die.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun("foo = 0; bar = 0;");
    }
  
    // Bump the code age so that flushing is triggered while the function
    // object is still located in new-space.
    const int kAgingThreshold = 6;
    for (int i = 0; i < kAgingThreshold; i++) {
      function->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
      function2->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
    }
  
    // Simulate incremental marking so that the functions are enqueued as
    // code flushing candidates. Then kill one of the functions. Finally
    // perform a scavenge while incremental marking is still running.
    SimulateIncrementalMarking();
    *function2.location() = NULL;
    HEAP->CollectGarbage(NEW_SPACE, "test scavenge while marking");
  
    // Simulate one final GC to make sure the candidate queue is sane.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    CHECK(!function->shared()->is_compiled() || function->IsOptimized());
    CHECK(!function->is_compiled() || function->IsOptimized());
  }
  
  
  TEST(TestCodeFlushingIncrementalAbort) {
    // If we do not flush code this test is invalid.
    if (!FLAG_flush_code || !FLAG_flush_code_incrementally) return;
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    Heap* heap = isolate->heap();
    v8::HandleScope scope(CcTest::isolate());
    const char* source = "function foo() {"
                         "  var x = 42;"
                         "  var y = 42;"
                         "  var z = x + y;"
                         "};"
                         "foo()";
    Handle<String> foo_name = factory->InternalizeUtf8String("foo");
  
    // This compile will add the code to the compilation cache.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun(source);
    }
  
    // Check function is compiled.
    Object* func_value = Isolate::Current()->context()->global_object()->
        GetProperty(*foo_name)->ToObjectChecked();
    CHECK(func_value->IsJSFunction());
    Handle<JSFunction> function(JSFunction::cast(func_value));
    CHECK(function->shared()->is_compiled());
  
    // The code will survive at least two GCs.
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    CHECK(function->shared()->is_compiled());
  
    // Bump the code age so that flushing is triggered.
    const int kAgingThreshold = 6;
    for (int i = 0; i < kAgingThreshold; i++) {
      function->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
    }
  
    // Simulate incremental marking so that the function is enqueued as
    // code flushing candidate.
    SimulateIncrementalMarking();
  
  #ifdef ENABLE_DEBUGGER_SUPPORT
    // Enable the debugger and add a breakpoint while incremental marking
    // is running so that incremental marking aborts and code flushing is
    // disabled.
    int position = 0;
    Handle<Object> breakpoint_object(Smi::FromInt(0), isolate);
    isolate->debug()->SetBreakPoint(function, breakpoint_object, &position);
    isolate->debug()->ClearAllBreakPoints();
  #endif  // ENABLE_DEBUGGER_SUPPORT
  
    // Force optimization now that code flushing is disabled.
    { v8::HandleScope scope(CcTest::isolate());
      CompileRun("%OptimizeFunctionOnNextCall(foo); foo();");
    }
  
    // Simulate one final GC to make sure the candidate queue is sane.
    heap->CollectAllGarbage(Heap::kNoGCFlags);
    CHECK(function->shared()->is_compiled() || !function->IsOptimized());
    CHECK(function->is_compiled() || !function->IsOptimized());
  }
  
  
  // Count the number of native contexts in the weak list of native contexts.
  int CountNativeContexts() {
    int count = 0;
    Object* object = HEAP->native_contexts_list();
    while (!object->IsUndefined()) {
      count++;
      object = Context::cast(object)->get(Context::NEXT_CONTEXT_LINK);
    }
    return count;
  }
  
  
  // Count the number of user functions in the weak list of optimized
  // functions attached to a native context.
  static int CountOptimizedUserFunctions(v8::Handle<v8::Context> context) {
    int count = 0;
    Handle<Context> icontext = v8::Utils::OpenHandle(*context);
    Object* object = icontext->get(Context::OPTIMIZED_FUNCTIONS_LIST);
    while (object->IsJSFunction() && !JSFunction::cast(object)->IsBuiltin()) {
      count++;
      object = JSFunction::cast(object)->next_function_link();
    }
    return count;
  }
  
  
  TEST(TestInternalWeakLists) {
    v8::V8::Initialize();
  
    // Some flags turn Scavenge collections into Mark-sweep collections
    // and hence are incompatible with this test case.
    if (FLAG_gc_global || FLAG_stress_compaction) return;
  
    static const int kNumTestContexts = 10;
  
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    HandleScope scope(isolate);
    v8::Handle<v8::Context> ctx[kNumTestContexts];
  
    CHECK_EQ(0, CountNativeContexts());
  
    // Create a number of global contests which gets linked together.
    for (int i = 0; i < kNumTestContexts; i++) {
      ctx[i] = v8::Context::New(v8::Isolate::GetCurrent());
  
      // Collect garbage that might have been created by one of the
      // installed extensions.
      isolate->compilation_cache()->Clear();
      heap->CollectAllGarbage(Heap::kNoGCFlags);
  
      bool opt = (FLAG_always_opt && i::V8::UseCrankshaft());
  
      CHECK_EQ(i + 1, CountNativeContexts());
  
      ctx[i]->Enter();
  
      // Create a handle scope so no function objects get stuch in the outer
      // handle scope
      HandleScope scope(isolate);
      const char* source = "function f1() { };"
                           "function f2() { };"
                           "function f3() { };"
                           "function f4() { };"
                           "function f5() { };";
      CompileRun(source);
      CHECK_EQ(0, CountOptimizedUserFunctions(ctx[i]));
      CompileRun("f1()");
      CHECK_EQ(opt ? 1 : 0, CountOptimizedUserFunctions(ctx[i]));
      CompileRun("f2()");
      CHECK_EQ(opt ? 2 : 0, CountOptimizedUserFunctions(ctx[i]));
      CompileRun("f3()");
      CHECK_EQ(opt ? 3 : 0, CountOptimizedUserFunctions(ctx[i]));
      CompileRun("f4()");
      CHECK_EQ(opt ? 4 : 0, CountOptimizedUserFunctions(ctx[i]));
      CompileRun("f5()");
      CHECK_EQ(opt ? 5 : 0, CountOptimizedUserFunctions(ctx[i]));
  
      // Remove function f1, and
      CompileRun("f1=null");
  
      // Scavenge treats these references as strong.
      for (int j = 0; j < 10; j++) {
        HEAP->PerformScavenge();
        CHECK_EQ(opt ? 5 : 0, CountOptimizedUserFunctions(ctx[i]));
      }
  
      // Mark compact handles the weak references.
      isolate->compilation_cache()->Clear();
      heap->CollectAllGarbage(Heap::kNoGCFlags);
      CHECK_EQ(opt ? 4 : 0, CountOptimizedUserFunctions(ctx[i]));
  
      // Get rid of f3 and f5 in the same way.
      CompileRun("f3=null");
      for (int j = 0; j < 10; j++) {
        HEAP->PerformScavenge();
        CHECK_EQ(opt ? 4 : 0, CountOptimizedUserFunctions(ctx[i]));
      }
      HEAP->CollectAllGarbage(Heap::kNoGCFlags);
      CHECK_EQ(opt ? 3 : 0, CountOptimizedUserFunctions(ctx[i]));
      CompileRun("f5=null");
      for (int j = 0; j < 10; j++) {
        HEAP->PerformScavenge();
        CHECK_EQ(opt ? 3 : 0, CountOptimizedUserFunctions(ctx[i]));
      }
      HEAP->CollectAllGarbage(Heap::kNoGCFlags);
      CHECK_EQ(opt ? 2 : 0, CountOptimizedUserFunctions(ctx[i]));
  
      ctx[i]->Exit();
    }
  
    // Force compilation cache cleanup.
    HEAP->NotifyContextDisposed();
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    // Dispose the native contexts one by one.
    for (int i = 0; i < kNumTestContexts; i++) {
      // TODO(dcarney): is there a better way to do this?
      i::Object** unsafe = reinterpret_cast<i::Object**>(*ctx[i]);
      *unsafe = HEAP->undefined_value();
      ctx[i].Clear();
  
      // Scavenge treats these references as strong.
      for (int j = 0; j < 10; j++) {
        HEAP->PerformScavenge();
        CHECK_EQ(kNumTestContexts - i, CountNativeContexts());
      }
  
      // Mark compact handles the weak references.
      HEAP->CollectAllGarbage(Heap::kNoGCFlags);
      CHECK_EQ(kNumTestContexts - i - 1, CountNativeContexts());
    }
  
    CHECK_EQ(0, CountNativeContexts());
  }
  
  
  // Count the number of native contexts in the weak list of native contexts
  // causing a GC after the specified number of elements.
  static int CountNativeContextsWithGC(Isolate* isolate, int n) {
    Heap* heap = isolate->heap();
    int count = 0;
    Handle<Object> object(heap->native_contexts_list(), isolate);
    while (!object->IsUndefined()) {
      count++;
      if (count == n) heap->CollectAllGarbage(Heap::kNoGCFlags);
      object =
          Handle<Object>(Context::cast(*object)->get(Context::NEXT_CONTEXT_LINK),
                         isolate);
    }
    return count;
  }
  
  
  // Count the number of user functions in the weak list of optimized
  // functions attached to a native context causing a GC after the
  // specified number of elements.
  static int CountOptimizedUserFunctionsWithGC(v8::Handle<v8::Context> context,
                                               int n) {
    int count = 0;
    Handle<Context> icontext = v8::Utils::OpenHandle(*context);
    Isolate* isolate = icontext->GetIsolate();
    Handle<Object> object(icontext->get(Context::OPTIMIZED_FUNCTIONS_LIST),
                          isolate);
    while (object->IsJSFunction() &&
           !Handle<JSFunction>::cast(object)->IsBuiltin()) {
      count++;
      if (count == n) isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags);
      object = Handle<Object>(
          Object::cast(JSFunction::cast(*object)->next_function_link()),
          isolate);
    }
    return count;
  }
  
  
  TEST(TestInternalWeakListsTraverseWithGC) {
    v8::V8::Initialize();
    Isolate* isolate = Isolate::Current();
  
    static const int kNumTestContexts = 10;
  
    HandleScope scope(isolate);
    v8::Handle<v8::Context> ctx[kNumTestContexts];
  
    CHECK_EQ(0, CountNativeContexts());
  
    // Create an number of contexts and check the length of the weak list both
    // with and without GCs while iterating the list.
    for (int i = 0; i < kNumTestContexts; i++) {
      ctx[i] = v8::Context::New(v8::Isolate::GetCurrent());
      CHECK_EQ(i + 1, CountNativeContexts());
      CHECK_EQ(i + 1, CountNativeContextsWithGC(isolate, i / 2 + 1));
    }
  
    bool opt = (FLAG_always_opt && i::V8::UseCrankshaft());
  
    // Compile a number of functions the length of the weak list of optimized
    // functions both with and without GCs while iterating the list.
    ctx[0]->Enter();
    const char* source = "function f1() { };"
                         "function f2() { };"
                         "function f3() { };"
                         "function f4() { };"
                         "function f5() { };";
    CompileRun(source);
    CHECK_EQ(0, CountOptimizedUserFunctions(ctx[0]));
    CompileRun("f1()");
    CHECK_EQ(opt ? 1 : 0, CountOptimizedUserFunctions(ctx[0]));
    CHECK_EQ(opt ? 1 : 0, CountOptimizedUserFunctionsWithGC(ctx[0], 1));
    CompileRun("f2()");
    CHECK_EQ(opt ? 2 : 0, CountOptimizedUserFunctions(ctx[0]));
    CHECK_EQ(opt ? 2 : 0, CountOptimizedUserFunctionsWithGC(ctx[0], 1));
    CompileRun("f3()");
    CHECK_EQ(opt ? 3 : 0, CountOptimizedUserFunctions(ctx[0]));
    CHECK_EQ(opt ? 3 : 0, CountOptimizedUserFunctionsWithGC(ctx[0], 1));
    CompileRun("f4()");
    CHECK_EQ(opt ? 4 : 0, CountOptimizedUserFunctions(ctx[0]));
    CHECK_EQ(opt ? 4 : 0, CountOptimizedUserFunctionsWithGC(ctx[0], 2));
    CompileRun("f5()");
    CHECK_EQ(opt ? 5 : 0, CountOptimizedUserFunctions(ctx[0]));
    CHECK_EQ(opt ? 5 : 0, CountOptimizedUserFunctionsWithGC(ctx[0], 4));
  
    ctx[0]->Exit();
  }
  
  
  TEST(TestSizeOfObjects) {
    v8::V8::Initialize();
  
    // Get initial heap size after several full GCs, which will stabilize
    // the heap size and return with sweeping finished completely.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    CHECK(HEAP->old_pointer_space()->IsLazySweepingComplete());
    int initial_size = static_cast<int>(HEAP->SizeOfObjects());
  
    {
      // Allocate objects on several different old-space pages so that
      // lazy sweeping kicks in for subsequent GC runs.
      AlwaysAllocateScope always_allocate;
      int filler_size = static_cast<int>(FixedArray::SizeFor(8192));
      for (int i = 1; i <= 100; i++) {
        HEAP->AllocateFixedArray(8192, TENURED)->ToObjectChecked();
        CHECK_EQ(initial_size + i * filler_size,
                 static_cast<int>(HEAP->SizeOfObjects()));
      }
    }
  
    // The heap size should go back to initial size after a full GC, even
    // though sweeping didn't finish yet.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    // Normally sweeping would not be complete here, but no guarantees.
  
    CHECK_EQ(initial_size, static_cast<int>(HEAP->SizeOfObjects()));
  
    // Advancing the sweeper step-wise should not change the heap size.
    while (!HEAP->old_pointer_space()->IsLazySweepingComplete()) {
      HEAP->old_pointer_space()->AdvanceSweeper(KB);
      CHECK_EQ(initial_size, static_cast<int>(HEAP->SizeOfObjects()));
    }
  }
  
  
  TEST(TestSizeOfObjectsVsHeapIteratorPrecision) {
    CcTest::InitializeVM();
    HEAP->EnsureHeapIsIterable();
    intptr_t size_of_objects_1 = HEAP->SizeOfObjects();
    HeapIterator iterator(HEAP);
    intptr_t size_of_objects_2 = 0;
    for (HeapObject* obj = iterator.next();
         obj != NULL;
         obj = iterator.next()) {
      if (!obj->IsFreeSpace()) {
        size_of_objects_2 += obj->Size();
      }
    }
    // Delta must be within 5% of the larger result.
    // TODO(gc): Tighten this up by distinguishing between byte
    // arrays that are real and those that merely mark free space
    // on the heap.
    if (size_of_objects_1 > size_of_objects_2) {
      intptr_t delta = size_of_objects_1 - size_of_objects_2;
      PrintF("Heap::SizeOfObjects: %" V8_PTR_PREFIX "d, "
             "Iterator: %" V8_PTR_PREFIX "d, "
             "delta: %" V8_PTR_PREFIX "d\n",
             size_of_objects_1, size_of_objects_2, delta);
      CHECK_GT(size_of_objects_1 / 20, delta);
    } else {
      intptr_t delta = size_of_objects_2 - size_of_objects_1;
      PrintF("Heap::SizeOfObjects: %" V8_PTR_PREFIX "d, "
             "Iterator: %" V8_PTR_PREFIX "d, "
             "delta: %" V8_PTR_PREFIX "d\n",
             size_of_objects_1, size_of_objects_2, delta);
      CHECK_GT(size_of_objects_2 / 20, delta);
    }
  }
  
  
  static void FillUpNewSpace(NewSpace* new_space) {
    // Fill up new space to the point that it is completely full. Make sure
    // that the scavenger does not undo the filling.
    Heap* heap = new_space->heap();
    Isolate* isolate = heap->isolate();
    Factory* factory = isolate->factory();
    HandleScope scope(isolate);
    AlwaysAllocateScope always_allocate;
    intptr_t available = new_space->EffectiveCapacity() - new_space->Size();
    intptr_t number_of_fillers = (available / FixedArray::SizeFor(32)) - 1;
    for (intptr_t i = 0; i < number_of_fillers; i++) {
      CHECK(heap->InNewSpace(*factory->NewFixedArray(32, NOT_TENURED)));
    }
  }
  
  
  TEST(GrowAndShrinkNewSpace) {
    CcTest::InitializeVM();
    NewSpace* new_space = HEAP->new_space();
  
    if (HEAP->ReservedSemiSpaceSize() == HEAP->InitialSemiSpaceSize() ||
        HEAP->MaxSemiSpaceSize() == HEAP->InitialSemiSpaceSize()) {
      // The max size cannot exceed the reserved size, since semispaces must be
      // always within the reserved space.  We can't test new space growing and
      // shrinking if the reserved size is the same as the minimum (initial) size.
      return;
    }
  
    // Explicitly growing should double the space capacity.
    intptr_t old_capacity, new_capacity;
    old_capacity = new_space->Capacity();
    new_space->Grow();
    new_capacity = new_space->Capacity();
    CHECK(2 * old_capacity == new_capacity);
  
    old_capacity = new_space->Capacity();
    FillUpNewSpace(new_space);
    new_capacity = new_space->Capacity();
    CHECK(old_capacity == new_capacity);
  
    // Explicitly shrinking should not affect space capacity.
    old_capacity = new_space->Capacity();
    new_space->Shrink();
    new_capacity = new_space->Capacity();
    CHECK(old_capacity == new_capacity);
  
    // Let the scavenger empty the new space.
    HEAP->CollectGarbage(NEW_SPACE);
    CHECK_LE(new_space->Size(), old_capacity);
  
    // Explicitly shrinking should halve the space capacity.
    old_capacity = new_space->Capacity();
    new_space->Shrink();
    new_capacity = new_space->Capacity();
    CHECK(old_capacity == 2 * new_capacity);
  
    // Consecutive shrinking should not affect space capacity.
    old_capacity = new_space->Capacity();
    new_space->Shrink();
    new_space->Shrink();
    new_space->Shrink();
    new_capacity = new_space->Capacity();
    CHECK(old_capacity == new_capacity);
  }
  
  
  TEST(CollectingAllAvailableGarbageShrinksNewSpace) {
    CcTest::InitializeVM();
  
    if (HEAP->ReservedSemiSpaceSize() == HEAP->InitialSemiSpaceSize() ||
        HEAP->MaxSemiSpaceSize() == HEAP->InitialSemiSpaceSize()) {
      // The max size cannot exceed the reserved size, since semispaces must be
      // always within the reserved space.  We can't test new space growing and
      // shrinking if the reserved size is the same as the minimum (initial) size.
      return;
    }
  
    v8::HandleScope scope(CcTest::isolate());
    NewSpace* new_space = HEAP->new_space();
    intptr_t old_capacity, new_capacity;
    old_capacity = new_space->Capacity();
    new_space->Grow();
    new_capacity = new_space->Capacity();
    CHECK(2 * old_capacity == new_capacity);
    FillUpNewSpace(new_space);
    HEAP->CollectAllAvailableGarbage();
    new_capacity = new_space->Capacity();
    CHECK(old_capacity == new_capacity);
  }
  
  
  static int NumberOfGlobalObjects() {
    int count = 0;
    HeapIterator iterator(HEAP);
    for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next()) {
      if (obj->IsGlobalObject()) count++;
    }
    return count;
  }
  
  
  // Test that we don't embed maps from foreign contexts into
  // optimized code.
  TEST(LeakNativeContextViaMap) {
    i::FLAG_allow_natives_syntax = true;
    v8::Isolate* isolate = v8::Isolate::GetCurrent();
    v8::HandleScope outer_scope(isolate);
    v8::Persistent<v8::Context> ctx1p;
    v8::Persistent<v8::Context> ctx2p;
    {
      v8::HandleScope scope(isolate);
      ctx1p.Reset(isolate, v8::Context::New(isolate));
      ctx2p.Reset(isolate, v8::Context::New(isolate));
      v8::Local<v8::Context>::New(isolate, ctx1p)->Enter();
    }
  
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(4, NumberOfGlobalObjects());
  
    {
      v8::HandleScope inner_scope(isolate);
      CompileRun("var v = {x: 42}");
      v8::Local<v8::Context> ctx1 = v8::Local<v8::Context>::New(isolate, ctx1p);
      v8::Local<v8::Context> ctx2 = v8::Local<v8::Context>::New(isolate, ctx2p);
      v8::Local<v8::Value> v = ctx1->Global()->Get(v8_str("v"));
      ctx2->Enter();
      ctx2->Global()->Set(v8_str("o"), v);
      v8::Local<v8::Value> res = CompileRun(
          "function f() { return o.x; }"
          "for (var i = 0; i < 10; ++i) f();"
          "%OptimizeFunctionOnNextCall(f);"
          "f();");
      CHECK_EQ(42, res->Int32Value());
      ctx2->Global()->Set(v8_str("o"), v8::Int32::New(0));
      ctx2->Exit();
      v8::Local<v8::Context>::New(isolate, ctx1)->Exit();
      ctx1p.Dispose(isolate);
      v8::V8::ContextDisposedNotification();
    }
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(2, NumberOfGlobalObjects());
    ctx2p.Dispose(isolate);
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(0, NumberOfGlobalObjects());
  }
  
  
  // Test that we don't embed functions from foreign contexts into
  // optimized code.
  TEST(LeakNativeContextViaFunction) {
    i::FLAG_allow_natives_syntax = true;
    v8::Isolate* isolate = v8::Isolate::GetCurrent();
    v8::HandleScope outer_scope(isolate);
    v8::Persistent<v8::Context> ctx1p;
    v8::Persistent<v8::Context> ctx2p;
    {
      v8::HandleScope scope(isolate);
      ctx1p.Reset(isolate, v8::Context::New(isolate));
      ctx2p.Reset(isolate, v8::Context::New(isolate));
      v8::Local<v8::Context>::New(isolate, ctx1p)->Enter();
    }
  
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(4, NumberOfGlobalObjects());
  
    {
      v8::HandleScope inner_scope(isolate);
      CompileRun("var v = function() { return 42; }");
      v8::Local<v8::Context> ctx1 = v8::Local<v8::Context>::New(isolate, ctx1p);
      v8::Local<v8::Context> ctx2 = v8::Local<v8::Context>::New(isolate, ctx2p);
      v8::Local<v8::Value> v = ctx1->Global()->Get(v8_str("v"));
      ctx2->Enter();
      ctx2->Global()->Set(v8_str("o"), v);
      v8::Local<v8::Value> res = CompileRun(
          "function f(x) { return x(); }"
          "for (var i = 0; i < 10; ++i) f(o);"
          "%OptimizeFunctionOnNextCall(f);"
          "f(o);");
      CHECK_EQ(42, res->Int32Value());
      ctx2->Global()->Set(v8_str("o"), v8::Int32::New(0));
      ctx2->Exit();
      ctx1->Exit();
      ctx1p.Dispose(ctx1->GetIsolate());
      v8::V8::ContextDisposedNotification();
    }
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(2, NumberOfGlobalObjects());
    ctx2p.Dispose(isolate);
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(0, NumberOfGlobalObjects());
  }
  
  
  TEST(LeakNativeContextViaMapKeyed) {
    i::FLAG_allow_natives_syntax = true;
    v8::Isolate* isolate = v8::Isolate::GetCurrent();
    v8::HandleScope outer_scope(isolate);
    v8::Persistent<v8::Context> ctx1p;
    v8::Persistent<v8::Context> ctx2p;
    {
      v8::HandleScope scope(isolate);
      ctx1p.Reset(isolate, v8::Context::New(isolate));
      ctx2p.Reset(isolate, v8::Context::New(isolate));
      v8::Local<v8::Context>::New(isolate, ctx1p)->Enter();
    }
  
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(4, NumberOfGlobalObjects());
  
    {
      v8::HandleScope inner_scope(isolate);
      CompileRun("var v = [42, 43]");
      v8::Local<v8::Context> ctx1 = v8::Local<v8::Context>::New(isolate, ctx1p);
      v8::Local<v8::Context> ctx2 = v8::Local<v8::Context>::New(isolate, ctx2p);
      v8::Local<v8::Value> v = ctx1->Global()->Get(v8_str("v"));
      ctx2->Enter();
      ctx2->Global()->Set(v8_str("o"), v);
      v8::Local<v8::Value> res = CompileRun(
          "function f() { return o[0]; }"
          "for (var i = 0; i < 10; ++i) f();"
          "%OptimizeFunctionOnNextCall(f);"
          "f();");
      CHECK_EQ(42, res->Int32Value());
      ctx2->Global()->Set(v8_str("o"), v8::Int32::New(0));
      ctx2->Exit();
      ctx1->Exit();
      ctx1p.Dispose(ctx1->GetIsolate());
      v8::V8::ContextDisposedNotification();
    }
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(2, NumberOfGlobalObjects());
    ctx2p.Dispose(isolate);
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(0, NumberOfGlobalObjects());
  }
  
  
  TEST(LeakNativeContextViaMapProto) {
    i::FLAG_allow_natives_syntax = true;
    v8::Isolate* isolate = v8::Isolate::GetCurrent();
    v8::HandleScope outer_scope(isolate);
    v8::Persistent<v8::Context> ctx1p;
    v8::Persistent<v8::Context> ctx2p;
    {
      v8::HandleScope scope(isolate);
      ctx1p.Reset(isolate, v8::Context::New(isolate));
      ctx2p.Reset(isolate, v8::Context::New(isolate));
      v8::Local<v8::Context>::New(isolate, ctx1p)->Enter();
    }
  
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(4, NumberOfGlobalObjects());
  
    {
      v8::HandleScope inner_scope(isolate);
      CompileRun("var v = { y: 42}");
      v8::Local<v8::Context> ctx1 = v8::Local<v8::Context>::New(isolate, ctx1p);
      v8::Local<v8::Context> ctx2 = v8::Local<v8::Context>::New(isolate, ctx2p);
      v8::Local<v8::Value> v = ctx1->Global()->Get(v8_str("v"));
      ctx2->Enter();
      ctx2->Global()->Set(v8_str("o"), v);
      v8::Local<v8::Value> res = CompileRun(
          "function f() {"
          "  var p = {x: 42};"
          "  p.__proto__ = o;"
          "  return p.x;"
          "}"
          "for (var i = 0; i < 10; ++i) f();"
          "%OptimizeFunctionOnNextCall(f);"
          "f();");
      CHECK_EQ(42, res->Int32Value());
      ctx2->Global()->Set(v8_str("o"), v8::Int32::New(0));
      ctx2->Exit();
      ctx1->Exit();
      ctx1p.Dispose(isolate);
      v8::V8::ContextDisposedNotification();
    }
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(2, NumberOfGlobalObjects());
    ctx2p.Dispose(isolate);
    HEAP->CollectAllAvailableGarbage();
    CHECK_EQ(0, NumberOfGlobalObjects());
  }
  
  
  TEST(InstanceOfStubWriteBarrier) {
    i::FLAG_allow_natives_syntax = true;
  #ifdef VERIFY_HEAP
    i::FLAG_verify_heap = true;
  #endif
  
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft()) return;
    if (i::FLAG_force_marking_deque_overflows) return;
    v8::HandleScope outer_scope(v8::Isolate::GetCurrent());
  
    {
      v8::HandleScope scope(v8::Isolate::GetCurrent());
      CompileRun(
          "function foo () { }"
          "function mkbar () { return new (new Function(\"\")) (); }"
          "function f (x) { return (x instanceof foo); }"
          "function g () { f(mkbar()); }"
          "f(new foo()); f(new foo());"
          "%OptimizeFunctionOnNextCall(f);"
          "f(new foo()); g();");
    }
  
    IncrementalMarking* marking = HEAP->incremental_marking();
    marking->Abort();
    marking->Start();
  
    Handle<JSFunction> f =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
  
    CHECK(f->IsOptimized());
  
    while (!Marking::IsBlack(Marking::MarkBitFrom(f->code())) &&
           !marking->IsStopped()) {
      // Discard any pending GC requests otherwise we will get GC when we enter
      // code below.
      marking->Step(MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
    }
  
    CHECK(marking->IsMarking());
  
    {
      v8::HandleScope scope(v8::Isolate::GetCurrent());
      v8::Handle<v8::Object> global = v8::Context::GetCurrent()->Global();
      v8::Handle<v8::Function> g =
          v8::Handle<v8::Function>::Cast(global->Get(v8_str("g")));
      g->Call(global, 0, NULL);
    }
  
    HEAP->incremental_marking()->set_should_hurry(true);
    HEAP->CollectGarbage(OLD_POINTER_SPACE);
  }
  
  
  TEST(PrototypeTransitionClearing) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
  
    CompileRun(
        "var base = {};"
        "var live = [];"
        "for (var i = 0; i < 10; i++) {"
        "  var object = {};"
        "  var prototype = {};"
        "  object.__proto__ = prototype;"
        "  if (i >= 3) live.push(object, prototype);"
        "}");
  
    Handle<JSObject> baseObject =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Object>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("base"))));
  
    // Verify that only dead prototype transitions are cleared.
    CHECK_EQ(10, baseObject->map()->NumberOfProtoTransitions());
    HEAP->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
    const int transitions = 10 - 3;
    CHECK_EQ(transitions, baseObject->map()->NumberOfProtoTransitions());
  
    // Verify that prototype transitions array was compacted.
    FixedArray* trans = baseObject->map()->GetPrototypeTransitions();
    for (int i = 0; i < transitions; i++) {
      int j = Map::kProtoTransitionHeaderSize +
          i * Map::kProtoTransitionElementsPerEntry;
      CHECK(trans->get(j + Map::kProtoTransitionMapOffset)->IsMap());
      Object* proto = trans->get(j + Map::kProtoTransitionPrototypeOffset);
      CHECK(proto->IsTheHole() || proto->IsJSObject());
    }
  
    // Make sure next prototype is placed on an old-space evacuation candidate.
    Handle<JSObject> prototype;
    PagedSpace* space = HEAP->old_pointer_space();
    {
      AlwaysAllocateScope always_allocate;
      SimulateFullSpace(space);
      prototype = factory->NewJSArray(32 * KB, FAST_HOLEY_ELEMENTS, TENURED);
    }
  
    // Add a prototype on an evacuation candidate and verify that transition
    // clearing correctly records slots in prototype transition array.
    i::FLAG_always_compact = true;
    Handle<Map> map(baseObject->map());
    CHECK(!space->LastPage()->Contains(
        map->GetPrototypeTransitions()->address()));
    CHECK(space->LastPage()->Contains(prototype->address()));
    JSObject::SetPrototype(baseObject, prototype, false);
    CHECK(Map::GetPrototypeTransition(map, prototype)->IsMap());
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    CHECK(Map::GetPrototypeTransition(map, prototype)->IsMap());
  }
  
  
  TEST(ResetSharedFunctionInfoCountersDuringIncrementalMarking) {
    i::FLAG_stress_compaction = false;
    i::FLAG_allow_natives_syntax = true;
  #ifdef VERIFY_HEAP
    i::FLAG_verify_heap = true;
  #endif
  
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft()) return;
    v8::HandleScope outer_scope(v8::Isolate::GetCurrent());
  
    {
      v8::HandleScope scope(v8::Isolate::GetCurrent());
      CompileRun(
          "function f () {"
          "  var s = 0;"
          "  for (var i = 0; i < 100; i++)  s += i;"
          "  return s;"
          "}"
          "f(); f();"
          "%OptimizeFunctionOnNextCall(f);"
          "f();");
    }
    Handle<JSFunction> f =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
    CHECK(f->IsOptimized());
  
    IncrementalMarking* marking = HEAP->incremental_marking();
    marking->Abort();
    marking->Start();
  
    // The following two calls will increment HEAP->global_ic_age().
    const int kLongIdlePauseInMs = 1000;
    v8::V8::ContextDisposedNotification();
    v8::V8::IdleNotification(kLongIdlePauseInMs);
  
    while (!marking->IsStopped() && !marking->IsComplete()) {
      marking->Step(1 * MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
    }
    if (!marking->IsStopped() || marking->should_hurry()) {
      // We don't normally finish a GC via Step(), we normally finish by
      // setting the stack guard and then do the final steps in the stack
      // guard interrupt.  But here we didn't ask for that, and there is no
      // JS code running to trigger the interrupt, so we explicitly finalize
      // here.
      HEAP->CollectAllGarbage(Heap::kNoGCFlags,
                              "Test finalizing incremental mark-sweep");
    }
  
    CHECK_EQ(HEAP->global_ic_age(), f->shared()->ic_age());
    CHECK_EQ(0, f->shared()->opt_count());
    CHECK_EQ(0, f->shared()->code()->profiler_ticks());
  }
  
  
  TEST(ResetSharedFunctionInfoCountersDuringMarkSweep) {
    i::FLAG_stress_compaction = false;
    i::FLAG_allow_natives_syntax = true;
  #ifdef VERIFY_HEAP
    i::FLAG_verify_heap = true;
  #endif
  
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft()) return;
    v8::HandleScope outer_scope(CcTest::isolate());
  
    {
      v8::HandleScope scope(CcTest::isolate());
      CompileRun(
          "function f () {"
          "  var s = 0;"
          "  for (var i = 0; i < 100; i++)  s += i;"
          "  return s;"
          "}"
          "f(); f();"
          "%OptimizeFunctionOnNextCall(f);"
          "f();");
    }
    Handle<JSFunction> f =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
    CHECK(f->IsOptimized());
  
    HEAP->incremental_marking()->Abort();
  
    // The following two calls will increment HEAP->global_ic_age().
    // Since incremental marking is off, IdleNotification will do full GC.
    const int kLongIdlePauseInMs = 1000;
    v8::V8::ContextDisposedNotification();
    v8::V8::IdleNotification(kLongIdlePauseInMs);
  
    CHECK_EQ(HEAP->global_ic_age(), f->shared()->ic_age());
    CHECK_EQ(0, f->shared()->opt_count());
    CHECK_EQ(0, f->shared()->code()->profiler_ticks());
  }
  
  
  // Test that HAllocateObject will always return an object in new-space.
  TEST(OptimizedAllocationAlwaysInNewSpace) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
  
    SimulateFullSpace(HEAP->new_space());
    AlwaysAllocateScope always_allocate;
    v8::Local<v8::Value> res = CompileRun(
        "function c(x) {"
        "  this.x = x;"
        "  for (var i = 0; i < 32; i++) {"
        "    this['x' + i] = x;"
        "  }"
        "}"
        "function f(x) { return new c(x); };"
        "f(1); f(2); f(3);"
        "%OptimizeFunctionOnNextCall(f);"
        "f(4);");
    CHECK_EQ(4, res->ToObject()->GetRealNamedProperty(v8_str("x"))->Int32Value());
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
  
    CHECK(HEAP->InNewSpace(*o));
  }
  
  
  TEST(OptimizedPretenuringObjectArrayLiterals) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = [{}, {}, {}];"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
  
    CHECK(HEAP->InOldPointerSpace(o->elements()));
    CHECK(HEAP->InOldPointerSpace(*o));
  }
  
  
  TEST(OptimizedPretenuringMixedInObjectProperties) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = {a: {c: 2.2, d: {}}, b: 1.1};"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
  
    CHECK(HEAP->InOldPointerSpace(*o));
    CHECK(HEAP->InOldPointerSpace(o->RawFastPropertyAt(0)));
    CHECK(HEAP->InOldDataSpace(o->RawFastPropertyAt(1)));
  
    JSObject* inner_object = reinterpret_cast<JSObject*>(o->RawFastPropertyAt(0));
    CHECK(HEAP->InOldPointerSpace(inner_object));
    CHECK(HEAP->InOldDataSpace(inner_object->RawFastPropertyAt(0)));
    CHECK(HEAP->InOldPointerSpace(inner_object->RawFastPropertyAt(1)));
  }
  
  
  TEST(OptimizedPretenuringDoubleArrayProperties) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = {a: 1.1, b: 2.2};"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
  
    CHECK(HEAP->InOldPointerSpace(*o));
    CHECK(HEAP->InOldDataSpace(o->properties()));
  }
  
  
  TEST(OptimizedPretenuringdoubleArrayLiterals) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = [1.1, 2.2, 3.3];"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
  
    CHECK(HEAP->InOldDataSpace(o->elements()));
    CHECK(HEAP->InOldPointerSpace(*o));
  }
  
  
  TEST(OptimizedPretenuringNestedMixedArrayLiterals) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = [[{}, {}, {}],[1.1, 2.2, 3.3]];"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    v8::Local<v8::Value> int_array = v8::Object::Cast(*res)->Get(v8_str("0"));
    Handle<JSObject> int_array_handle =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(int_array));
    v8::Local<v8::Value> double_array = v8::Object::Cast(*res)->Get(v8_str("1"));
    Handle<JSObject> double_array_handle =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(double_array));
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
    CHECK(HEAP->InOldPointerSpace(*o));
    CHECK(HEAP->InOldPointerSpace(*int_array_handle));
    CHECK(HEAP->InOldPointerSpace(int_array_handle->elements()));
    CHECK(HEAP->InOldPointerSpace(*double_array_handle));
    CHECK(HEAP->InOldDataSpace(double_array_handle->elements()));
  }
  
  
  TEST(OptimizedPretenuringNestedObjectLiterals) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = [[{}, {}, {}],[{}, {}, {}]];"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    v8::Local<v8::Value> int_array_1 = v8::Object::Cast(*res)->Get(v8_str("0"));
    Handle<JSObject> int_array_handle_1 =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(int_array_1));
    v8::Local<v8::Value> int_array_2 = v8::Object::Cast(*res)->Get(v8_str("1"));
    Handle<JSObject> int_array_handle_2 =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(int_array_2));
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
    CHECK(HEAP->InOldPointerSpace(*o));
    CHECK(HEAP->InOldPointerSpace(*int_array_handle_1));
    CHECK(HEAP->InOldPointerSpace(int_array_handle_1->elements()));
    CHECK(HEAP->InOldPointerSpace(*int_array_handle_2));
    CHECK(HEAP->InOldPointerSpace(int_array_handle_2->elements()));
  }
  
  
  TEST(OptimizedPretenuringNestedDoubleLiterals) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = [[1.1, 1.2, 1.3],[2.1, 2.2, 2.3]];"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    v8::Local<v8::Value> double_array_1 =
        v8::Object::Cast(*res)->Get(v8_str("0"));
    Handle<JSObject> double_array_handle_1 =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(double_array_1));
    v8::Local<v8::Value> double_array_2 =
        v8::Object::Cast(*res)->Get(v8_str("1"));
    Handle<JSObject> double_array_handle_2 =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(double_array_2));
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
    CHECK(HEAP->InOldPointerSpace(*o));
    CHECK(HEAP->InOldPointerSpace(*double_array_handle_1));
    CHECK(HEAP->InOldDataSpace(double_array_handle_1->elements()));
    CHECK(HEAP->InOldPointerSpace(*double_array_handle_2));
    CHECK(HEAP->InOldDataSpace(double_array_handle_2->elements()));
  }
  
  
  // Test regular array literals allocation.
  TEST(OptimizedAllocationArrayLiterals) {
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
  
    v8::Local<v8::Value> res = CompileRun(
        "function f() {"
        "  var numbers = new Array(1, 2, 3);"
        "  numbers[0] = 3.14;"
        "  return numbers;"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
    CHECK_EQ(static_cast<int>(3.14),
             v8::Object::Cast(*res)->Get(v8_str("0"))->Int32Value());
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
  
    CHECK(HEAP->InNewSpace(o->elements()));
  }
  
  
  TEST(OptimizedPretenuringCallNew) {
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_pretenuring_call_new = true;
    CcTest::InitializeVM();
    if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
    if (i::FLAG_gc_global || i::FLAG_stress_compaction) return;
    v8::HandleScope scope(CcTest::isolate());
    HEAP->SetNewSpaceHighPromotionModeActive(true);
  
    AlwaysAllocateScope always_allocate;
    v8::Local<v8::Value> res = CompileRun(
        "function g() { this.a = 0; }"
        "function f() {"
        "  return new g();"
        "};"
        "f(); f(); f();"
        "%OptimizeFunctionOnNextCall(f);"
        "f();");
  
    Handle<JSObject> o =
        v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
    CHECK(HEAP->InOldPointerSpace(*o));
  }
  
  
  static int CountMapTransitions(Map* map) {
    return map->transitions()->number_of_transitions();
  }
  
  
  // Test that map transitions are cleared and maps are collected with
  // incremental marking as well.
  TEST(Regress1465) {
    i::FLAG_stress_compaction = false;
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_trace_incremental_marking = true;
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
    static const int transitions_count = 256;
  
    {
      AlwaysAllocateScope always_allocate;
      for (int i = 0; i < transitions_count; i++) {
        EmbeddedVector<char, 64> buffer;
        OS::SNPrintF(buffer, "var o = new Object; o.prop%d = %d;", i, i);
        CompileRun(buffer.start());
      }
      CompileRun("var root = new Object;");
    }
  
    Handle<JSObject> root =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Object>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("root"))));
  
    // Count number of live transitions before marking.
    int transitions_before = CountMapTransitions(root->map());
    CompileRun("%DebugPrint(root);");
    CHECK_EQ(transitions_count, transitions_before);
  
    SimulateIncrementalMarking();
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    // Count number of live transitions after marking.  Note that one transition
    // is left, because 'o' still holds an instance of one transition target.
    int transitions_after = CountMapTransitions(root->map());
    CompileRun("%DebugPrint(root);");
    CHECK_EQ(1, transitions_after);
  }
  
  
  TEST(Regress2143a) {
    i::FLAG_collect_maps = true;
    i::FLAG_incremental_marking = true;
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
  
    // Prepare a map transition from the root object together with a yet
    // untransitioned root object.
    CompileRun("var root = new Object;"
               "root.foo = 0;"
               "root = new Object;");
  
    SimulateIncrementalMarking();
  
    // Compile a StoreIC that performs the prepared map transition. This
    // will restart incremental marking and should make sure the root is
    // marked grey again.
    CompileRun("function f(o) {"
               "  o.foo = 0;"
               "}"
               "f(new Object);"
               "f(root);");
  
    // This bug only triggers with aggressive IC clearing.
    HEAP->AgeInlineCaches();
  
    // Explicitly request GC to perform final marking step and sweeping.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    Handle<JSObject> root =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Object>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("root"))));
  
    // The root object should be in a sane state.
    CHECK(root->IsJSObject());
    CHECK(root->map()->IsMap());
  }
  
  
  TEST(Regress2143b) {
    i::FLAG_collect_maps = true;
    i::FLAG_incremental_marking = true;
    i::FLAG_allow_natives_syntax = true;
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
  
    // Prepare a map transition from the root object together with a yet
    // untransitioned root object.
    CompileRun("var root = new Object;"
               "root.foo = 0;"
               "root = new Object;");
  
    SimulateIncrementalMarking();
  
    // Compile an optimized LStoreNamedField that performs the prepared
    // map transition. This will restart incremental marking and should
    // make sure the root is marked grey again.
    CompileRun("function f(o) {"
               "  o.foo = 0;"
               "}"
               "f(new Object);"
               "f(new Object);"
               "%OptimizeFunctionOnNextCall(f);"
               "f(root);"
               "%DeoptimizeFunction(f);");
  
    // This bug only triggers with aggressive IC clearing.
    HEAP->AgeInlineCaches();
  
    // Explicitly request GC to perform final marking step and sweeping.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    Handle<JSObject> root =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Object>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("root"))));
  
    // The root object should be in a sane state.
    CHECK(root->IsJSObject());
    CHECK(root->map()->IsMap());
  }
  
  
  TEST(ReleaseOverReservedPages) {
    i::FLAG_trace_gc = true;
    // The optimizer can allocate stuff, messing up the test.
    i::FLAG_crankshaft = false;
    i::FLAG_always_opt = false;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
    static const int number_of_test_pages = 20;
  
    // Prepare many pages with low live-bytes count.
    PagedSpace* old_pointer_space = HEAP->old_pointer_space();
    CHECK_EQ(1, old_pointer_space->CountTotalPages());
    for (int i = 0; i < number_of_test_pages; i++) {
      AlwaysAllocateScope always_allocate;
      SimulateFullSpace(old_pointer_space);
      factory->NewFixedArray(1, TENURED);
    }
    CHECK_EQ(number_of_test_pages + 1, old_pointer_space->CountTotalPages());
  
    // Triggering one GC will cause a lot of garbage to be discovered but
    // even spread across all allocated pages.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags, "triggered for preparation");
    CHECK_GE(number_of_test_pages + 1, old_pointer_space->CountTotalPages());
  
    // Triggering subsequent GCs should cause at least half of the pages
    // to be released to the OS after at most two cycles.
    HEAP->CollectAllGarbage(Heap::kNoGCFlags, "triggered by test 1");
    CHECK_GE(number_of_test_pages + 1, old_pointer_space->CountTotalPages());
    HEAP->CollectAllGarbage(Heap::kNoGCFlags, "triggered by test 2");
    CHECK_GE(number_of_test_pages + 1, old_pointer_space->CountTotalPages() * 2);
  
    // Triggering a last-resort GC should cause all pages to be released to the
    // OS so that other processes can seize the memory.  If we get a failure here
    // where there are 2 pages left instead of 1, then we should increase the
    // size of the first page a little in SizeOfFirstPage in spaces.cc.  The
    // first page should be small in order to reduce memory used when the VM
    // boots, but if the 20 small arrays don't fit on the first page then that's
    // an indication that it is too small.
    HEAP->CollectAllAvailableGarbage("triggered really hard");
    CHECK_EQ(1, old_pointer_space->CountTotalPages());
  }
  
  
  TEST(Regress2237) {
    i::FLAG_stress_compaction = false;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
    Handle<String> slice(HEAP->empty_string());
  
    {
      // Generate a parent that lives in new-space.
      v8::HandleScope inner_scope(CcTest::isolate());
      const char* c = "This text is long enough to trigger sliced strings.";
      Handle<String> s = factory->NewStringFromAscii(CStrVector(c));
      CHECK(s->IsSeqOneByteString());
      CHECK(HEAP->InNewSpace(*s));
  
      // Generate a sliced string that is based on the above parent and
      // lives in old-space.
      SimulateFullSpace(HEAP->new_space());
      AlwaysAllocateScope always_allocate;
      Handle<String> t = factory->NewProperSubString(s, 5, 35);
      CHECK(t->IsSlicedString());
      CHECK(!HEAP->InNewSpace(*t));
      *slice.location() = *t.location();
    }
  
    CHECK(SlicedString::cast(*slice)->parent()->IsSeqOneByteString());
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
    CHECK(SlicedString::cast(*slice)->parent()->IsSeqOneByteString());
  }
  
  
  #ifdef OBJECT_PRINT
  TEST(PrintSharedFunctionInfo) {
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
    const char* source = "f = function() { return 987654321; }\n"
                         "g = function() { return 123456789; }\n";
    CompileRun(source);
    Handle<JSFunction> g =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("g"))));
  
    DisallowHeapAllocation no_allocation;
    g->shared()->PrintLn();
  }
  #endif  // OBJECT_PRINT
  
  
  TEST(Regress2211) {
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
  
    v8::Handle<v8::String> value = v8_str("val string");
    Smi* hash = Smi::FromInt(321);
    Heap* heap = Isolate::Current()->heap();
  
    for (int i = 0; i < 2; i++) {
      // Store identity hash first and common hidden property second.
      v8::Handle<v8::Object> obj = v8::Object::New();
      Handle<JSObject> internal_obj = v8::Utils::OpenHandle(*obj);
      CHECK(internal_obj->HasFastProperties());
  
      // In the first iteration, set hidden value first and identity hash second.
      // In the second iteration, reverse the order.
      if (i == 0) obj->SetHiddenValue(v8_str("key string"), value);
      MaybeObject* maybe_obj = internal_obj->SetIdentityHash(hash,
                                                             ALLOW_CREATION);
      CHECK(!maybe_obj->IsFailure());
      if (i == 1) obj->SetHiddenValue(v8_str("key string"), value);
  
      // Check values.
      CHECK_EQ(hash,
               internal_obj->GetHiddenProperty(heap->identity_hash_string()));
      CHECK(value->Equals(obj->GetHiddenValue(v8_str("key string"))));
  
      // Check size.
      DescriptorArray* descriptors = internal_obj->map()->instance_descriptors();
      ObjectHashTable* hashtable = ObjectHashTable::cast(
          internal_obj->RawFastPropertyAt(descriptors->GetFieldIndex(0)));
      // HashTable header (5) and 4 initial entries (8).
      CHECK_LE(hashtable->SizeFor(hashtable->length()), 13 * kPointerSize);
    }
  }
  
  
  TEST(IncrementalMarkingClearsTypeFeedbackCells) {
    if (i::FLAG_always_opt) return;
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
    v8::Local<v8::Value> fun1, fun2;
  
    {
      LocalContext env;
      CompileRun("function fun() {};");
      fun1 = env->Global()->Get(v8_str("fun"));
    }
  
    {
      LocalContext env;
      CompileRun("function fun() {};");
      fun2 = env->Global()->Get(v8_str("fun"));
    }
  
    // Prepare function f that contains type feedback for closures
    // originating from two different native contexts.
    v8::Context::GetCurrent()->Global()->Set(v8_str("fun1"), fun1);
    v8::Context::GetCurrent()->Global()->Set(v8_str("fun2"), fun2);
    CompileRun("function f(a, b) { a(); b(); } f(fun1, fun2);");
    Handle<JSFunction> f =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
    Handle<TypeFeedbackCells> cells(TypeFeedbackInfo::cast(
        f->shared()->code()->type_feedback_info())->type_feedback_cells());
  
    CHECK_EQ(2, cells->CellCount());
    CHECK(cells->GetCell(0)->value()->IsJSFunction());
    CHECK(cells->GetCell(1)->value()->IsJSFunction());
  
    SimulateIncrementalMarking();
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    CHECK_EQ(2, cells->CellCount());
    CHECK(cells->GetCell(0)->value()->IsTheHole());
    CHECK(cells->GetCell(1)->value()->IsTheHole());
  }
  
  
  static Code* FindFirstIC(Code* code, Code::Kind kind) {
    int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
               RelocInfo::ModeMask(RelocInfo::CONSTRUCT_CALL) |
               RelocInfo::ModeMask(RelocInfo::CODE_TARGET_WITH_ID) |
               RelocInfo::ModeMask(RelocInfo::CODE_TARGET_CONTEXT);
    for (RelocIterator it(code, mask); !it.done(); it.next()) {
      RelocInfo* info = it.rinfo();
      Code* target = Code::GetCodeFromTargetAddress(info->target_address());
      if (target->is_inline_cache_stub() && target->kind() == kind) {
        return target;
      }
    }
    return NULL;
  }
  
  
  TEST(IncrementalMarkingPreservesMonomorhpicIC) {
    if (i::FLAG_always_opt) return;
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
  
    // Prepare function f that contains a monomorphic IC for object
    // originating from the same native context.
    CompileRun("function fun() { this.x = 1; }; var obj = new fun();"
               "function f(o) { return o.x; } f(obj); f(obj);");
    Handle<JSFunction> f =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
  
    Code* ic_before = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
    CHECK(ic_before->ic_state() == MONOMORPHIC);
  
    SimulateIncrementalMarking();
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    Code* ic_after = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
    CHECK(ic_after->ic_state() == MONOMORPHIC);
  }
  
  
  TEST(IncrementalMarkingClearsMonomorhpicIC) {
    if (i::FLAG_always_opt) return;
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
    v8::Local<v8::Value> obj1;
  
    {
      LocalContext env;
      CompileRun("function fun() { this.x = 1; }; var obj = new fun();");
      obj1 = env->Global()->Get(v8_str("obj"));
    }
  
    // Prepare function f that contains a monomorphic IC for object
    // originating from a different native context.
    v8::Context::GetCurrent()->Global()->Set(v8_str("obj1"), obj1);
    CompileRun("function f(o) { return o.x; } f(obj1); f(obj1);");
    Handle<JSFunction> f =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
  
    Code* ic_before = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
    CHECK(ic_before->ic_state() == MONOMORPHIC);
  
    // Fire context dispose notification.
    v8::V8::ContextDisposedNotification();
    SimulateIncrementalMarking();
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    Code* ic_after = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
    CHECK(ic_after->ic_state() == UNINITIALIZED);
  }
  
  
  TEST(IncrementalMarkingClearsPolymorhpicIC) {
    if (i::FLAG_always_opt) return;
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
    v8::Local<v8::Value> obj1, obj2;
  
    {
      LocalContext env;
      CompileRun("function fun() { this.x = 1; }; var obj = new fun();");
      obj1 = env->Global()->Get(v8_str("obj"));
    }
  
    {
      LocalContext env;
      CompileRun("function fun() { this.x = 2; }; var obj = new fun();");
      obj2 = env->Global()->Get(v8_str("obj"));
    }
  
    // Prepare function f that contains a polymorphic IC for objects
    // originating from two different native contexts.
    v8::Context::GetCurrent()->Global()->Set(v8_str("obj1"), obj1);
    v8::Context::GetCurrent()->Global()->Set(v8_str("obj2"), obj2);
    CompileRun("function f(o) { return o.x; } f(obj1); f(obj1); f(obj2);");
    Handle<JSFunction> f =
        v8::Utils::OpenHandle(
            *v8::Handle<v8::Function>::Cast(
                v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
  
    Code* ic_before = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
    CHECK(ic_before->ic_state() == POLYMORPHIC);
  
    // Fire context dispose notification.
    v8::V8::ContextDisposedNotification();
    SimulateIncrementalMarking();
    HEAP->CollectAllGarbage(Heap::kNoGCFlags);
  
    Code* ic_after = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
    CHECK(ic_after->ic_state() == UNINITIALIZED);
  }
  
  
  class SourceResource: public v8::String::ExternalAsciiStringResource {
   public:
    explicit SourceResource(const char* data)
      : data_(data), length_(strlen(data)) { }
  
    virtual void Dispose() {
      i::DeleteArray(data_);
      data_ = NULL;
    }
  
    const char* data() const { return data_; }
  
    size_t length() const { return length_; }
  
    bool IsDisposed() { return data_ == NULL; }
  
   private:
    const char* data_;
    size_t length_;
  };
  
  
  void ReleaseStackTraceDataTest(const char* source) {
    // Test that the data retained by the Error.stack accessor is released
    // after the first time the accessor is fired.  We use external string
    // to check whether the data is being released since the external string
    // resource's callback is fired when the external string is GC'ed.
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
    SourceResource* resource = new SourceResource(i::StrDup(source));
    {
      v8::HandleScope scope(CcTest::isolate());
      v8::Handle<v8::String> source_string = v8::String::NewExternal(resource);
      v8::Script::Compile(source_string)->Run();
      CHECK(!resource->IsDisposed());
    }
    HEAP->CollectAllAvailableGarbage();
  
    // External source has been released.
    CHECK(resource->IsDisposed());
    delete resource;
  }
  
  
  TEST(ReleaseStackTraceData) {
    static const char* source1 = "var error = null;            "
    /* Normal Error */           "try {                        "
                                 "  throw new Error();         "
                                 "} catch (e) {                "
                                 "  error = e;                 "
                                 "}                            ";
    static const char* source2 = "var error = null;            "
    /* Stack overflow */         "try {                        "
                                 "  (function f() { f(); })(); "
                                 "} catch (e) {                "
                                 "  error = e;                 "
                                 "}                            ";
    ReleaseStackTraceDataTest(source1);
    ReleaseStackTraceDataTest(source2);
  }
  
  
  TEST(Regression144230) {
    i::FLAG_stress_compaction = false;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    HandleScope scope(isolate);
  
    // First make sure that the uninitialized CallIC stub is on a single page
    // that will later be selected as an evacuation candidate.
    {
      HandleScope inner_scope(isolate);
      AlwaysAllocateScope always_allocate;
      SimulateFullSpace(heap->code_space());
      isolate->stub_cache()->ComputeCallInitialize(9, RelocInfo::CODE_TARGET);
    }
  
    // Second compile a CallIC and execute it once so that it gets patched to
    // the pre-monomorphic stub. These code objects are on yet another page.
    {
      HandleScope inner_scope(isolate);
      AlwaysAllocateScope always_allocate;
      SimulateFullSpace(heap->code_space());
      CompileRun("var o = { f:function(a,b,c,d,e,f,g,h,i) {}};"
                 "function call() { o.f(1,2,3,4,5,6,7,8,9); };"
                 "call();");
    }
  
    // Third we fill up the last page of the code space so that it does not get
    // chosen as an evacuation candidate.
    {
      HandleScope inner_scope(isolate);
      AlwaysAllocateScope always_allocate;
      CompileRun("for (var i = 0; i < 2000; i++) {"
                 "  eval('function f' + i + '() { return ' + i +'; };' +"
                 "       'f' + i + '();');"
                 "}");
    }
    heap->CollectAllGarbage(Heap::kNoGCFlags);
  
    // Fourth is the tricky part. Make sure the code containing the CallIC is
    // visited first without clearing the IC. The shared function info is then
    // visited later, causing the CallIC to be cleared.
    Handle<String> name = isolate->factory()->InternalizeUtf8String("call");
    Handle<GlobalObject> global(isolate->context()->global_object());
    MaybeObject* maybe_call = global->GetProperty(*name);
    JSFunction* call = JSFunction::cast(maybe_call->ToObjectChecked());
    USE(global->SetProperty(*name, Smi::FromInt(0), NONE, kNonStrictMode));
    isolate->compilation_cache()->Clear();
    call->shared()->set_ic_age(heap->global_ic_age() + 1);
    Handle<Object> call_code(call->code(), isolate);
    Handle<Object> call_function(call, isolate);
  
    // Now we are ready to mess up the heap.
    heap->CollectAllGarbage(Heap::kReduceMemoryFootprintMask);
  
    // Either heap verification caught the problem already or we go kaboom once
    // the CallIC is executed the next time.
    USE(global->SetProperty(*name, *call_function, NONE, kNonStrictMode));
    CompileRun("call();");
  }
  
  
  TEST(Regress159140) {
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_flush_code_incrementally = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    HandleScope scope(isolate);
  
    // Perform one initial GC to enable code flushing.
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
  
    // Prepare several closures that are all eligible for code flushing
    // because all reachable ones are not optimized. Make sure that the
    // optimized code object is directly reachable through a handle so
    // that it is marked black during incremental marking.
    Handle<Code> code;
    {
      HandleScope inner_scope(isolate);
      CompileRun("function h(x) {}"
                 "function mkClosure() {"
                 "  return function(x) { return x + 1; };"
                 "}"
                 "var f = mkClosure();"
                 "var g = mkClosure();"
                 "f(1); f(2);"
                 "g(1); g(2);"
                 "h(1); h(2);"
                 "%OptimizeFunctionOnNextCall(f); f(3);"
                 "%OptimizeFunctionOnNextCall(h); h(3);");
  
      Handle<JSFunction> f =
          v8::Utils::OpenHandle(
              *v8::Handle<v8::Function>::Cast(
                  v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
      CHECK(f->is_compiled());
      CompileRun("f = null;");
  
      Handle<JSFunction> g =
          v8::Utils::OpenHandle(
              *v8::Handle<v8::Function>::Cast(
                  v8::Context::GetCurrent()->Global()->Get(v8_str("g"))));
      CHECK(g->is_compiled());
      const int kAgingThreshold = 6;
      for (int i = 0; i < kAgingThreshold; i++) {
        g->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
      }
  
      code = inner_scope.CloseAndEscape(Handle<Code>(f->code()));
    }
  
    // Simulate incremental marking so that the functions are enqueued as
    // code flushing candidates. Then optimize one function. Finally
    // finish the GC to complete code flushing.
    SimulateIncrementalMarking();
    CompileRun("%OptimizeFunctionOnNextCall(g); g(3);");
    heap->CollectAllGarbage(Heap::kNoGCFlags);
  
    // Unoptimized code is missing and the deoptimizer will go ballistic.
    CompileRun("g('bozo');");
  }
  
  
  TEST(Regress165495) {
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_flush_code_incrementally = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    HandleScope scope(isolate);
  
    // Perform one initial GC to enable code flushing.
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
  
    // Prepare an optimized closure that the optimized code map will get
    // populated. Then age the unoptimized code to trigger code flushing
    // but make sure the optimized code is unreachable.
    {
      HandleScope inner_scope(isolate);
      CompileRun("function mkClosure() {"
                 "  return function(x) { return x + 1; };"
                 "}"
                 "var f = mkClosure();"
                 "f(1); f(2);"
                 "%OptimizeFunctionOnNextCall(f); f(3);");
  
      Handle<JSFunction> f =
          v8::Utils::OpenHandle(
              *v8::Handle<v8::Function>::Cast(
                  v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
      CHECK(f->is_compiled());
      const int kAgingThreshold = 6;
      for (int i = 0; i < kAgingThreshold; i++) {
        f->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
      }
  
      CompileRun("f = null;");
    }
  
    // Simulate incremental marking so that unoptimized code is flushed
    // even though it still is cached in the optimized code map.
    SimulateIncrementalMarking();
    heap->CollectAllGarbage(Heap::kNoGCFlags);
  
    // Make a new closure that will get code installed from the code map.
    // Unoptimized code is missing and the deoptimizer will go ballistic.
    CompileRun("var g = mkClosure(); g('bozo');");
  }
  
  
  TEST(Regress169209) {
    i::FLAG_stress_compaction = false;
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_flush_code_incrementally = true;
  
    // Experimental natives are compiled during snapshot deserialization.
    // This test breaks because heap layout changes in a way that closure
    // is visited before shared function info.
    i::FLAG_harmony_typed_arrays = false;
    i::FLAG_harmony_array_buffer = false;
  
    // Disable loading the i18n extension which breaks the assumptions of this
    // test about the heap layout.
    i::FLAG_enable_i18n = false;
  
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    HandleScope scope(isolate);
  
    // Perform one initial GC to enable code flushing.
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
  
    // Prepare a shared function info eligible for code flushing for which
    // the unoptimized code will be replaced during optimization.
    Handle<SharedFunctionInfo> shared1;
    {
      HandleScope inner_scope(isolate);
      CompileRun("function f() { return 'foobar'; }"
                 "function g(x) { if (x) f(); }"
                 "f();"
                 "g(false);"
                 "g(false);");
  
      Handle<JSFunction> f =
          v8::Utils::OpenHandle(
              *v8::Handle<v8::Function>::Cast(
                  v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
      CHECK(f->is_compiled());
      const int kAgingThreshold = 6;
      for (int i = 0; i < kAgingThreshold; i++) {
        f->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
      }
  
      shared1 = inner_scope.CloseAndEscape(handle(f->shared(), isolate));
    }
  
    // Prepare a shared function info eligible for code flushing that will
    // represent the dangling tail of the candidate list.
    Handle<SharedFunctionInfo> shared2;
    {
      HandleScope inner_scope(isolate);
      CompileRun("function flushMe() { return 0; }"
                 "flushMe(1);");
  
      Handle<JSFunction> f =
          v8::Utils::OpenHandle(
              *v8::Handle<v8::Function>::Cast(
                  v8::Context::GetCurrent()->Global()->Get(v8_str("flushMe"))));
      CHECK(f->is_compiled());
      const int kAgingThreshold = 6;
      for (int i = 0; i < kAgingThreshold; i++) {
        f->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
      }
  
      shared2 = inner_scope.CloseAndEscape(handle(f->shared(), isolate));
    }
  
    // Simulate incremental marking and collect code flushing candidates.
    SimulateIncrementalMarking();
    CHECK(shared1->code()->gc_metadata() != NULL);
  
    // Optimize function and make sure the unoptimized code is replaced.
  #ifdef DEBUG
    FLAG_stop_at = "f";
  #endif
    CompileRun("%OptimizeFunctionOnNextCall(g);"
               "g(false);");
  
    // Finish garbage collection cycle.
    heap->CollectAllGarbage(Heap::kNoGCFlags);
    CHECK(shared1->code()->gc_metadata() == NULL);
  }
  
  
  // Helper function that simulates a fill new-space in the heap.
  static inline void AllocateAllButNBytes(v8::internal::NewSpace* space,
                                          int extra_bytes) {
    int space_remaining = static_cast<int>(
        *space->allocation_limit_address() - *space->allocation_top_address());
    CHECK(space_remaining >= extra_bytes);
    int new_linear_size = space_remaining - extra_bytes;
    v8::internal::MaybeObject* maybe = space->AllocateRaw(new_linear_size);
    v8::internal::FreeListNode* node = v8::internal::FreeListNode::cast(maybe);
    node->set_size(space->heap(), new_linear_size);
  }
  
  
  TEST(Regress169928) {
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_crankshaft = false;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Factory* factory = isolate->factory();
    v8::HandleScope scope(CcTest::isolate());
  
    // Some flags turn Scavenge collections into Mark-sweep collections
    // and hence are incompatible with this test case.
    if (FLAG_gc_global || FLAG_stress_compaction) return;
  
    // Prepare the environment
    CompileRun("function fastliteralcase(literal, value) {"
               "    literal[0] = value;"
               "    return literal;"
               "}"
               "function get_standard_literal() {"
               "    var literal = [1, 2, 3];"
               "    return literal;"
               "}"
               "obj = fastliteralcase(get_standard_literal(), 1);"
               "obj = fastliteralcase(get_standard_literal(), 1.5);"
               "obj = fastliteralcase(get_standard_literal(), 2);");
  
    // prepare the heap
    v8::Local<v8::String> mote_code_string =
        v8_str("fastliteralcase(mote, 2.5);");
  
    v8::Local<v8::String> array_name = v8_str("mote");
    v8::Context::GetCurrent()->Global()->Set(array_name, v8::Int32::New(0));
  
    // First make sure we flip spaces
    HEAP->CollectGarbage(NEW_SPACE);
  
    // Allocate the object.
    Handle<FixedArray> array_data = factory->NewFixedArray(2, NOT_TENURED);
    array_data->set(0, Smi::FromInt(1));
    array_data->set(1, Smi::FromInt(2));
  
    AllocateAllButNBytes(HEAP->new_space(),
                         JSArray::kSize + AllocationMemento::kSize +
                         kPointerSize);
  
    Handle<JSArray> array = factory->NewJSArrayWithElements(array_data,
                                                            FAST_SMI_ELEMENTS,
                                                            NOT_TENURED);
  
    CHECK_EQ(Smi::FromInt(2), array->length());
    CHECK(array->HasFastSmiOrObjectElements());
  
    // We need filler the size of AllocationMemento object, plus an extra
    // fill pointer value.
    MaybeObject* maybe_object = HEAP->AllocateRaw(
        AllocationMemento::kSize + kPointerSize, NEW_SPACE, OLD_POINTER_SPACE);
    Object* obj = NULL;
    CHECK(maybe_object->ToObject(&obj));
    Address addr_obj = reinterpret_cast<Address>(
        reinterpret_cast<byte*>(obj - kHeapObjectTag));
    HEAP->CreateFillerObjectAt(addr_obj,
                               AllocationMemento::kSize + kPointerSize);
  
    // Give the array a name, making sure not to allocate strings.
    v8::Handle<v8::Object> array_obj = v8::Utils::ToLocal(array);
    v8::Context::GetCurrent()->Global()->Set(array_name, array_obj);
  
    // This should crash with a protection violation if we are running a build
    // with the bug.
    AlwaysAllocateScope aa_scope;
    v8::Script::Compile(mote_code_string)->Run();
  }
  
  
  TEST(Regress168801) {
    i::FLAG_always_compact = true;
    i::FLAG_cache_optimized_code = false;
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_flush_code_incrementally = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    HandleScope scope(isolate);
  
    // Perform one initial GC to enable code flushing.
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
  
    // Ensure the code ends up on an evacuation candidate.
    SimulateFullSpace(heap->code_space());
  
    // Prepare an unoptimized function that is eligible for code flushing.
    Handle<JSFunction> function;
    {
      HandleScope inner_scope(isolate);
      CompileRun("function mkClosure() {"
                 "  return function(x) { return x + 1; };"
                 "}"
                 "var f = mkClosure();"
                 "f(1); f(2);");
  
      Handle<JSFunction> f =
          v8::Utils::OpenHandle(
              *v8::Handle<v8::Function>::Cast(
                  v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
      CHECK(f->is_compiled());
      const int kAgingThreshold = 6;
      for (int i = 0; i < kAgingThreshold; i++) {
        f->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
      }
  
      function = inner_scope.CloseAndEscape(handle(*f, isolate));
    }
  
    // Simulate incremental marking so that unoptimized function is enqueued as a
    // candidate for code flushing. The shared function info however will not be
    // explicitly enqueued.
    SimulateIncrementalMarking();
  
    // Now optimize the function so that it is taken off the candidate list.
    {
      HandleScope inner_scope(isolate);
      CompileRun("%OptimizeFunctionOnNextCall(f); f(3);");
    }
  
    // This cycle will bust the heap and subsequent cycles will go ballistic.
    heap->CollectAllGarbage(Heap::kNoGCFlags);
    heap->CollectAllGarbage(Heap::kNoGCFlags);
  }
  
  
  TEST(Regress173458) {
    i::FLAG_always_compact = true;
    i::FLAG_cache_optimized_code = false;
    i::FLAG_allow_natives_syntax = true;
    i::FLAG_flush_code_incrementally = true;
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    HandleScope scope(isolate);
  
    // Perform one initial GC to enable code flushing.
    heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
  
    // Ensure the code ends up on an evacuation candidate.
    SimulateFullSpace(heap->code_space());
  
    // Prepare an unoptimized function that is eligible for code flushing.
    Handle<JSFunction> function;
    {
      HandleScope inner_scope(isolate);
      CompileRun("function mkClosure() {"
                 "  return function(x) { return x + 1; };"
                 "}"
                 "var f = mkClosure();"
                 "f(1); f(2);");
  
      Handle<JSFunction> f =
          v8::Utils::OpenHandle(
              *v8::Handle<v8::Function>::Cast(
                  v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
      CHECK(f->is_compiled());
      const int kAgingThreshold = 6;
      for (int i = 0; i < kAgingThreshold; i++) {
        f->shared()->code()->MakeOlder(static_cast<MarkingParity>(i % 2));
      }
  
      function = inner_scope.CloseAndEscape(handle(*f, isolate));
    }
  
    // Simulate incremental marking so that unoptimized function is enqueued as a
    // candidate for code flushing. The shared function info however will not be
    // explicitly enqueued.
    SimulateIncrementalMarking();
  
  #ifdef ENABLE_DEBUGGER_SUPPORT
    // Now enable the debugger which in turn will disable code flushing.
    CHECK(isolate->debug()->Load());
  #endif  // ENABLE_DEBUGGER_SUPPORT
  
    // This cycle will bust the heap and subsequent cycles will go ballistic.
    heap->CollectAllGarbage(Heap::kNoGCFlags);
    heap->CollectAllGarbage(Heap::kNoGCFlags);
  }
  
  
  class DummyVisitor : public ObjectVisitor {
   public:
    void VisitPointers(Object** start, Object** end) { }
  };
  
  
  TEST(DeferredHandles) {
    CcTest::InitializeVM();
    Isolate* isolate = Isolate::Current();
    Heap* heap = isolate->heap();
    v8::HandleScope scope;
    v8::ImplementationUtilities::HandleScopeData* data =
        isolate->handle_scope_data();
    Handle<Object> init(heap->empty_string(), isolate);
    while (data->next < data->limit) {
      Handle<Object> obj(heap->empty_string(), isolate);
    }
    // An entire block of handles has been filled.
    // Next handle would require a new block.
    ASSERT(data->next == data->limit);
  
    DeferredHandleScope deferred(isolate);
    DummyVisitor visitor;
    isolate->handle_scope_implementer()->Iterate(&visitor);
    deferred.Detach();
  }
  
  
  TEST(IncrementalMarkingStepMakesBigProgressWithLargeObjects) {
    CcTest::InitializeVM();
    v8::HandleScope scope(CcTest::isolate());
    CompileRun("function f(n) {"
               "    var a = new Array(n);"
               "    for (var i = 0; i < n; i += 100) a[i] = i;"
               "};"
               "f(10 * 1024 * 1024);");
    IncrementalMarking* marking = HEAP->incremental_marking();
    if (marking->IsStopped()) marking->Start();
    // This big step should be sufficient to mark the whole array.
    marking->Step(100 * MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
    ASSERT(marking->IsComplete());
  }
  