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Vector-based ICs also need to hold maps weakly.

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Regular ICs in MONOMORPHIC and POLYMORPHIC state now hold onto maps with
WeakCells. Vector-based ICs should do the same.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/815953002

Cr-Commit-Position: refs/heads/master@{#25907}
This commit is contained in:
mvstanton 2014-12-19 08:53:41 -08:00 committed by Commit bot
parent 5ac1f8dabb
commit ad033893d6
3 changed files with 45 additions and 41 deletions
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11
src/code-stubs-hydrogen.cc
View File

@ -2043,8 +2043,13 @@ void CodeStubGraphBuilderBase::HandleArrayCases(HValue* array, HValue* receiver,
HValue* receiver_map = AddLoadMap(receiver, nullptr);
HValue* start =
keyed_load ? graph()->GetConstant1() : graph()->GetConstant0();
HValue* array_map = Add<HLoadKeyed>(array, start, nullptr, FAST_ELEMENTS,
HValue* weak_cell = Add<HLoadKeyed>(array, start, nullptr, FAST_ELEMENTS,
ALLOW_RETURN_HOLE);
// Load the weak cell value. It may be Smi(0), or a map. Compare nonetheless
// against the receiver_map.
HValue* array_map = Add<HLoadNamedField>(weak_cell, nullptr,
HObjectAccess::ForWeakCellValue());
IfBuilder if_correct_map(this);
if_correct_map.If<HCompareObjectEqAndBranch>(receiver_map, array_map);
if_correct_map.Then();
@ -2059,8 +2064,10 @@ void CodeStubGraphBuilderBase::HandleArrayCases(HValue* array, HValue* receiver,
start = keyed_load ? constant_three : constant_two;
HValue* key = builder.BeginBody(start, length, Token::LT);
{
HValue* array_map = Add<HLoadKeyed>(array, key, nullptr, FAST_ELEMENTS,
HValue* weak_cell = Add<HLoadKeyed>(array, key, nullptr, FAST_ELEMENTS,
ALLOW_RETURN_HOLE);
HValue* array_map = Add<HLoadNamedField>(
weak_cell, nullptr, HObjectAccess::ForWeakCellValue());
IfBuilder if_correct_poly_map(this);
if_correct_poly_map.If<HCompareObjectEqAndBranch>(receiver_map,
array_map);

53
src/type-feedback-vector.cc
View File

@ -223,12 +223,13 @@ Handle<FixedArray> FeedbackNexus::EnsureArrayOfSize(int length) {
void FeedbackNexus::InstallHandlers(int start_index, TypeHandleList* types,
CodeHandleList* handlers) {
Isolate* isolate = GetIsolate();
FixedArray* array = FixedArray::cast(GetFeedback());
Handle<FixedArray> array = handle(FixedArray::cast(GetFeedback()), isolate);
int receiver_count = types->length();
for (int current = 0; current < receiver_count; ++current) {
Handle<HeapType> type = types->at(current);
Handle<Map> map = IC::TypeToMap(*type, isolate);
array->set(start_index + (current * 2), *map);
Handle<WeakCell> cell = Map::WeakCellForMap(map);
array->set(start_index + (current * 2), *cell);
array->set(start_index + (current * 2 + 1), *handlers->at(current));
}
}
@ -244,6 +245,8 @@ InlineCacheState LoadICNexus::StateFromFeedback() const {
} else if (feedback == *vector()->PremonomorphicSentinel(isolate)) {
return PREMONOMORPHIC;
} else if (feedback->IsFixedArray()) {
// Determine state purely by our structure, don't check if the maps are
// cleared.
FixedArray* array = FixedArray::cast(feedback);
int length = array->length();
DCHECK(length >= 2);
@ -264,6 +267,8 @@ InlineCacheState KeyedLoadICNexus::StateFromFeedback() const {
} else if (feedback == *vector()->GenericSentinel(isolate)) {
return GENERIC;
} else if (feedback->IsFixedArray()) {
// Determine state purely by our structure, don't check if the maps are
// cleared.
FixedArray* array = FixedArray::cast(feedback);
int length = array->length();
DCHECK(length >= 3);
@ -344,7 +349,8 @@ void LoadICNexus::ConfigureMonomorphic(Handle<HeapType> type,
Handle<Code> handler) {
Handle<FixedArray> array = EnsureArrayOfSize(2);
Handle<Map> receiver_map = IC::TypeToMap(*type, GetIsolate());
array->set(0, *receiver_map);
Handle<WeakCell> cell = Map::WeakCellForMap(receiver_map);
array->set(0, *cell);
array->set(1, *handler);
}
@ -359,7 +365,8 @@ void KeyedLoadICNexus::ConfigureMonomorphic(Handle<Name> name,
} else {
array->set(0, *name);
}
array->set(1, *receiver_map);
Handle<WeakCell> cell = Map::WeakCellForMap(receiver_map);
array->set(1, *cell);
array->set(2, *handler);
}
@ -390,15 +397,20 @@ int FeedbackNexus::ExtractMaps(int start_index, MapHandleList* maps) const {
Isolate* isolate = GetIsolate();
Object* feedback = GetFeedback();
if (feedback->IsFixedArray()) {
int found = 0;
FixedArray* array = FixedArray::cast(feedback);
// The array should be of the form [<optional name>], then
// [map, handler, map, handler, ... ]
DCHECK(array->length() >= (2 + start_index));
for (int i = start_index; i < array->length(); i += 2) {
Map* map = Map::cast(array->get(i));
maps->Add(handle(map, isolate));
WeakCell* cell = WeakCell::cast(array->get(i));
if (!cell->cleared()) {
Map* map = Map::cast(cell->value());
maps->Add(handle(map, isolate));
found++;
}
}
return (array->length() - start_index) / 2;
return found;
}
return 0;
@ -411,11 +423,14 @@ MaybeHandle<Code> FeedbackNexus::FindHandlerForMap(int start_index,
if (feedback->IsFixedArray()) {
FixedArray* array = FixedArray::cast(feedback);
for (int i = start_index; i < array->length(); i += 2) {
Map* array_map = Map::cast(array->get(i));
if (array_map == *map) {
Code* code = Code::cast(array->get(i + 1));
DCHECK(code->kind() == Code::HANDLER);
return handle(code);
WeakCell* cell = WeakCell::cast(array->get(i));
if (!cell->cleared()) {
Map* array_map = Map::cast(cell->value());
if (array_map == *map) {
Code* code = Code::cast(array->get(i + 1));
DCHECK(code->kind() == Code::HANDLER);
return handle(code);
}
}
}
}
@ -431,13 +446,17 @@ bool FeedbackNexus::FindHandlers(int start_index, CodeHandleList* code_list,
if (feedback->IsFixedArray()) {
FixedArray* array = FixedArray::cast(feedback);
// The array should be of the form [<optional name>], then
// [map, handler, map, handler, ... ]
// [map, handler, map, handler, ... ]. Be sure to skip handlers whose maps
// have been cleared.
DCHECK(array->length() >= (2 + start_index));
for (int i = start_index; i < array->length(); i += 2) {
Code* code = Code::cast(array->get(i + 1));
DCHECK(code->kind() == Code::HANDLER);
code_list->Add(handle(code));
count++;
WeakCell* cell = WeakCell::cast(array->get(i));
if (!cell->cleared()) {
Code* code = Code::cast(array->get(i + 1));
DCHECK(code->kind() == Code::HANDLER);
code_list->Add(handle(code));
count++;
}
}
}
return count == length;

22
test/cctest/test-heap.cc
View File

@ -3407,8 +3407,6 @@ static void CheckVectorICCleared(Handle<JSFunction> f, int ic_slot_index) {
TEST(IncrementalMarkingPreservesMonomorphicIC) {
if (i::FLAG_always_opt) return;
// TODO(mvstanton): vector-ics need to treat maps weakly.
if (i::FLAG_vector_ics) return;
CcTest::InitializeVM();
v8::HandleScope scope(CcTest::isolate());
@ -3806,8 +3804,6 @@ TEST(Regress169209) {
i::FLAG_stress_compaction = false;
i::FLAG_allow_natives_syntax = true;
i::FLAG_flush_code_incrementally = true;
// TODO(mvstanton): vector ics need weak support.
if (i::FLAG_vector_ics) return;
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
@ -4161,8 +4157,6 @@ static int AllocationSitesCount(Heap* heap) {
TEST(EnsureAllocationSiteDependentCodesProcessed) {
// TODO(mvstanton): vector ics need weak support!
if (FLAG_vector_ics) return;
if (i::FLAG_always_opt || !i::FLAG_crankshaft) return;
i::FLAG_allow_natives_syntax = true;
CcTest::InitializeVM();
@ -4211,10 +4205,6 @@ TEST(EnsureAllocationSiteDependentCodesProcessed) {
heap->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask);
}
// TODO(mvstanton): this test fails when FLAG_vector_ics is true because
// monomorphic load ics are preserved, but also strongly walked. They
// end up keeping function bar alive.
// The site still exists because of our global handle, but the code is no
// longer referred to by dependent_code().
DependentCode::GroupStartIndexes starts(site->dependent_code());
@ -4225,8 +4215,6 @@ TEST(EnsureAllocationSiteDependentCodesProcessed) {
TEST(CellsInOptimizedCodeAreWeak) {
if (i::FLAG_always_opt || !i::FLAG_crankshaft) return;
// TODO(mvstanton): vector-ics need to treat maps weakly.
if (i::FLAG_vector_ics) return;
i::FLAG_weak_embedded_objects_in_optimized_code = true;
i::FLAG_allow_natives_syntax = true;
CcTest::InitializeVM();
@ -4269,8 +4257,6 @@ TEST(CellsInOptimizedCodeAreWeak) {
TEST(ObjectsInOptimizedCodeAreWeak) {
// TODO(mvstanton): vector ics need weak support!
if (FLAG_vector_ics) return;
if (i::FLAG_always_opt || !i::FLAG_crankshaft) return;
i::FLAG_weak_embedded_objects_in_optimized_code = true;
i::FLAG_allow_natives_syntax = true;
@ -4314,8 +4300,6 @@ TEST(ObjectsInOptimizedCodeAreWeak) {
TEST(NoWeakHashTableLeakWithIncrementalMarking) {
if (i::FLAG_always_opt || !i::FLAG_crankshaft) return;
if (!i::FLAG_incremental_marking) return;
// TODO(mvstanton): vector ics need weak support.
if (FLAG_vector_ics) return;
i::FLAG_weak_embedded_objects_in_optimized_code = true;
i::FLAG_allow_natives_syntax = true;
i::FLAG_compilation_cache = false;
@ -4487,8 +4471,6 @@ void CheckWeakness(const char* source) {
// Each of the following "weak IC" tests creates an IC that embeds a map with
// the prototype pointing to _proto_ and checks that the _proto_ dies on GC.
TEST(WeakMapInMonomorphicLoadIC) {
// TODO(mvstanton): vector ics need weak support!
if (FLAG_vector_ics) return;
CheckWeakness("function loadIC(obj) {"
" return obj.name;"
"}"
@ -4504,8 +4486,6 @@ TEST(WeakMapInMonomorphicLoadIC) {
TEST(WeakMapInPolymorphicLoadIC) {
// TODO(mvstanton): vector-ics need to treat maps weakly.
if (i::FLAG_vector_ics) return;
CheckWeakness(
"function loadIC(obj) {"
" return obj.name;"
@ -4525,8 +4505,6 @@ TEST(WeakMapInPolymorphicLoadIC) {
TEST(WeakMapInMonomorphicKeyedLoadIC) {
// TODO(mvstanton): vector ics need weak support!
if (FLAG_vector_ics) return;
CheckWeakness("function keyedLoadIC(obj, field) {"
" return obj[field];"
"}"