| // Copyright 2013 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "src/keys.h" |
| |
| #include "src/elements.h" |
| #include "src/factory.h" |
| #include "src/isolate-inl.h" |
| #include "src/objects-inl.h" |
| #include "src/property-descriptor.h" |
| #include "src/prototype.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| KeyAccumulator::~KeyAccumulator() { |
| for (size_t i = 0; i < elements_.size(); i++) { |
| delete elements_[i]; |
| } |
| } |
| |
| Handle<FixedArray> KeyAccumulator::GetKeys(GetKeysConversion convert) { |
| if (length_ == 0) { |
| return isolate_->factory()->empty_fixed_array(); |
| } |
| // Make sure we have all the lengths collected. |
| NextPrototype(); |
| |
| if (type_ == OWN_ONLY && !ownProxyKeys_.is_null()) { |
| return ownProxyKeys_; |
| } |
| // Assemble the result array by first adding the element keys and then the |
| // property keys. We use the total number of String + Symbol keys per level in |
| // |level_lengths_| and the available element keys in the corresponding bucket |
| // in |elements_| to deduce the number of keys to take from the |
| // |string_properties_| and |symbol_properties_| set. |
| Handle<FixedArray> result = isolate_->factory()->NewFixedArray(length_); |
| int insertion_index = 0; |
| int string_properties_index = 0; |
| int symbol_properties_index = 0; |
| // String and Symbol lengths always come in pairs: |
| size_t max_level = level_lengths_.size() / 2; |
| for (size_t level = 0; level < max_level; level++) { |
| int num_string_properties = level_lengths_[level * 2]; |
| int num_symbol_properties = level_lengths_[level * 2 + 1]; |
| int num_elements = 0; |
| if (num_string_properties < 0) { |
| // If the |num_string_properties| is negative, the current level contains |
| // properties from a proxy, hence we skip the integer keys in |elements_| |
| // since proxies define the complete ordering. |
| num_string_properties = -num_string_properties; |
| } else if (level < elements_.size()) { |
| // Add the element indices for this prototype level. |
| std::vector<uint32_t>* elements = elements_[level]; |
| num_elements = static_cast<int>(elements->size()); |
| for (int i = 0; i < num_elements; i++) { |
| Handle<Object> key; |
| if (convert == KEEP_NUMBERS) { |
| key = isolate_->factory()->NewNumberFromUint(elements->at(i)); |
| } else { |
| key = isolate_->factory()->Uint32ToString(elements->at(i)); |
| } |
| result->set(insertion_index, *key); |
| insertion_index++; |
| } |
| } |
| // Add the string property keys for this prototype level. |
| for (int i = 0; i < num_string_properties; i++) { |
| Object* key = string_properties_->KeyAt(string_properties_index); |
| result->set(insertion_index, key); |
| insertion_index++; |
| string_properties_index++; |
| } |
| // Add the symbol property keys for this prototype level. |
| for (int i = 0; i < num_symbol_properties; i++) { |
| Object* key = symbol_properties_->KeyAt(symbol_properties_index); |
| result->set(insertion_index, key); |
| insertion_index++; |
| symbol_properties_index++; |
| } |
| if (FLAG_trace_for_in_enumerate) { |
| PrintF("| strings=%d symbols=%d elements=%i ", num_string_properties, |
| num_symbol_properties, num_elements); |
| } |
| } |
| if (FLAG_trace_for_in_enumerate) { |
| PrintF("|| prototypes=%zu ||\n", max_level); |
| } |
| |
| DCHECK_EQ(insertion_index, length_); |
| return result; |
| } |
| |
| namespace { |
| |
| bool AccumulatorHasKey(std::vector<uint32_t>* sub_elements, uint32_t key) { |
| return std::binary_search(sub_elements->begin(), sub_elements->end(), key); |
| } |
| |
| } // namespace |
| |
| bool KeyAccumulator::AddKey(Object* key, AddKeyConversion convert) { |
| return AddKey(handle(key, isolate_), convert); |
| } |
| |
| bool KeyAccumulator::AddKey(Handle<Object> key, AddKeyConversion convert) { |
| if (key->IsSymbol()) { |
| if (filter_ & SKIP_SYMBOLS) return false; |
| if (Handle<Symbol>::cast(key)->is_private()) return false; |
| return AddSymbolKey(key); |
| } |
| if (filter_ & SKIP_STRINGS) return false; |
| // Make sure we do not add keys to a proxy-level (see AddKeysFromProxy). |
| DCHECK_LE(0, level_string_length_); |
| // In some cases (e.g. proxies) we might get in String-converted ints which |
| // should be added to the elements list instead of the properties. For |
| // proxies we have to convert as well but also respect the original order. |
| // Therefore we add a converted key to both sides |
| if (convert == CONVERT_TO_ARRAY_INDEX || convert == PROXY_MAGIC) { |
| uint32_t index = 0; |
| int prev_length = length_; |
| int prev_proto = level_string_length_; |
| if ((key->IsString() && Handle<String>::cast(key)->AsArrayIndex(&index)) || |
| key->ToArrayIndex(&index)) { |
| bool key_was_added = AddIntegerKey(index); |
| if (convert == CONVERT_TO_ARRAY_INDEX) return key_was_added; |
| if (convert == PROXY_MAGIC) { |
| // If we had an array index (number) and it wasn't added, the key |
| // already existed before, hence we cannot add it to the properties |
| // keys as it would lead to duplicate entries. |
| if (!key_was_added) { |
| return false; |
| } |
| length_ = prev_length; |
| level_string_length_ = prev_proto; |
| } |
| } |
| } |
| return AddStringKey(key, convert); |
| } |
| |
| bool KeyAccumulator::AddKey(uint32_t key) { return AddIntegerKey(key); } |
| |
| bool KeyAccumulator::AddIntegerKey(uint32_t key) { |
| // Make sure we do not add keys to a proxy-level (see AddKeysFromProxy). |
| // We mark proxy-levels with a negative length |
| DCHECK_LE(0, level_string_length_); |
| // Binary search over all but the last level. The last one might not be |
| // sorted yet. |
| for (size_t i = 1; i < elements_.size(); i++) { |
| if (AccumulatorHasKey(elements_[i - 1], key)) return false; |
| } |
| elements_.back()->push_back(key); |
| length_++; |
| return true; |
| } |
| |
| bool KeyAccumulator::AddStringKey(Handle<Object> key, |
| AddKeyConversion convert) { |
| if (string_properties_.is_null()) { |
| string_properties_ = OrderedHashSet::Allocate(isolate_, 16); |
| } |
| // TODO(cbruni): remove this conversion once we throw the correct TypeError |
| // for non-string/symbol elements returned by proxies |
| if (convert == PROXY_MAGIC && key->IsNumber()) { |
| key = isolate_->factory()->NumberToString(key); |
| } |
| int prev_size = string_properties_->NumberOfElements(); |
| string_properties_ = OrderedHashSet::Add(string_properties_, key); |
| if (prev_size < string_properties_->NumberOfElements()) { |
| length_++; |
| level_string_length_++; |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| bool KeyAccumulator::AddSymbolKey(Handle<Object> key) { |
| if (symbol_properties_.is_null()) { |
| symbol_properties_ = OrderedHashSet::Allocate(isolate_, 16); |
| } |
| int prev_size = symbol_properties_->NumberOfElements(); |
| symbol_properties_ = OrderedHashSet::Add(symbol_properties_, key); |
| if (prev_size < symbol_properties_->NumberOfElements()) { |
| length_++; |
| level_symbol_length_++; |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| void KeyAccumulator::AddKeys(Handle<FixedArray> array, |
| AddKeyConversion convert) { |
| int add_length = array->length(); |
| if (add_length == 0) return; |
| for (int i = 0; i < add_length; i++) { |
| Handle<Object> current(array->get(i), isolate_); |
| AddKey(current, convert); |
| } |
| } |
| |
| void KeyAccumulator::AddKeys(Handle<JSObject> array_like, |
| AddKeyConversion convert) { |
| DCHECK(array_like->IsJSArray() || array_like->HasSloppyArgumentsElements()); |
| ElementsAccessor* accessor = array_like->GetElementsAccessor(); |
| accessor->AddElementsToKeyAccumulator(array_like, this, convert); |
| } |
| |
| void KeyAccumulator::AddKeysFromProxy(Handle<JSObject> array_like) { |
| // Proxies define a complete list of keys with no distinction of |
| // elements and properties, which breaks the normal assumption for the |
| // KeyAccumulator. |
| AddKeys(array_like, PROXY_MAGIC); |
| // Invert the current length to indicate a present proxy, so we can ignore |
| // element keys for this level. Otherwise we would not fully respect the order |
| // given by the proxy. |
| level_string_length_ = -level_string_length_; |
| } |
| |
| MaybeHandle<FixedArray> FilterProxyKeys(Isolate* isolate, Handle<JSProxy> owner, |
| Handle<FixedArray> keys, |
| PropertyFilter filter) { |
| if (filter == ALL_PROPERTIES) { |
| // Nothing to do. |
| return keys; |
| } |
| int store_position = 0; |
| for (int i = 0; i < keys->length(); ++i) { |
| Handle<Name> key(Name::cast(keys->get(i)), isolate); |
| if (key->FilterKey(filter)) continue; // Skip this key. |
| if (filter & ONLY_ENUMERABLE) { |
| PropertyDescriptor desc; |
| Maybe<bool> found = |
| JSProxy::GetOwnPropertyDescriptor(isolate, owner, key, &desc); |
| MAYBE_RETURN(found, MaybeHandle<FixedArray>()); |
| if (!found.FromJust() || !desc.enumerable()) continue; // Skip this key. |
| } |
| // Keep this key. |
| if (store_position != i) { |
| keys->set(store_position, *key); |
| } |
| store_position++; |
| } |
| if (store_position == 0) return isolate->factory()->empty_fixed_array(); |
| keys->Shrink(store_position); |
| return keys; |
| } |
| |
| // Returns "nothing" in case of exception, "true" on success. |
| Maybe<bool> KeyAccumulator::AddKeysFromProxy(Handle<JSProxy> proxy, |
| Handle<FixedArray> keys) { |
| if (filter_proxy_keys_) { |
| ASSIGN_RETURN_ON_EXCEPTION_VALUE( |
| isolate_, keys, FilterProxyKeys(isolate_, proxy, keys, filter_), |
| Nothing<bool>()); |
| } |
| // Proxies define a complete list of keys with no distinction of |
| // elements and properties, which breaks the normal assumption for the |
| // KeyAccumulator. |
| if (type_ == OWN_ONLY) { |
| ownProxyKeys_ = keys; |
| level_string_length_ = keys->length(); |
| length_ = level_string_length_; |
| } else { |
| AddKeys(keys, PROXY_MAGIC); |
| } |
| // Invert the current length to indicate a present proxy, so we can ignore |
| // element keys for this level. Otherwise we would not fully respect the order |
| // given by the proxy. |
| level_string_length_ = -level_string_length_; |
| return Just(true); |
| } |
| |
| void KeyAccumulator::AddElementKeysFromInterceptor( |
| Handle<JSObject> array_like) { |
| AddKeys(array_like, CONVERT_TO_ARRAY_INDEX); |
| // The interceptor might introduce duplicates for the current level, since |
| // these keys get added after the objects's normal element keys. |
| SortCurrentElementsListRemoveDuplicates(); |
| } |
| |
| void KeyAccumulator::SortCurrentElementsListRemoveDuplicates() { |
| // Sort and remove duplicates from the current elements level and adjust. |
| // the lengths accordingly. |
| auto last_level = elements_.back(); |
| size_t nof_removed_keys = last_level->size(); |
| std::sort(last_level->begin(), last_level->end()); |
| last_level->erase(std::unique(last_level->begin(), last_level->end()), |
| last_level->end()); |
| // Adjust total length by the number of removed duplicates. |
| nof_removed_keys -= last_level->size(); |
| length_ -= static_cast<int>(nof_removed_keys); |
| } |
| |
| void KeyAccumulator::SortCurrentElementsList() { |
| if (elements_.empty()) return; |
| auto element_keys = elements_.back(); |
| std::sort(element_keys->begin(), element_keys->end()); |
| } |
| |
| void KeyAccumulator::NextPrototype() { |
| // Store the protoLength on the first call of this method. |
| if (!elements_.empty()) { |
| level_lengths_.push_back(level_string_length_); |
| level_lengths_.push_back(level_symbol_length_); |
| } |
| elements_.push_back(new std::vector<uint32_t>()); |
| level_string_length_ = 0; |
| level_symbol_length_ = 0; |
| } |
| |
| namespace { |
| |
| void TrySettingEmptyEnumCache(JSReceiver* object) { |
| Map* map = object->map(); |
| DCHECK_EQ(kInvalidEnumCacheSentinel, map->EnumLength()); |
| if (!map->OnlyHasSimpleProperties()) return; |
| if (map->IsJSProxyMap()) return; |
| if (map->NumberOfOwnDescriptors() > 0) { |
| int number_of_enumerable_own_properties = |
| map->NumberOfDescribedProperties(OWN_DESCRIPTORS, ENUMERABLE_STRINGS); |
| if (number_of_enumerable_own_properties > 0) return; |
| } |
| DCHECK(object->IsJSObject()); |
| map->SetEnumLength(0); |
| } |
| |
| bool CheckAndInitalizeSimpleEnumCache(JSReceiver* object) { |
| if (object->map()->EnumLength() == kInvalidEnumCacheSentinel) { |
| TrySettingEmptyEnumCache(object); |
| } |
| if (object->map()->EnumLength() != 0) return false; |
| DCHECK(object->IsJSObject()); |
| return !JSObject::cast(object)->HasEnumerableElements(); |
| } |
| } // namespace |
| |
| void FastKeyAccumulator::Prepare() { |
| DisallowHeapAllocation no_gc; |
| // Directly go for the fast path for OWN_ONLY keys. |
| if (type_ == OWN_ONLY) return; |
| // Fully walk the prototype chain and find the last prototype with keys. |
| is_receiver_simple_enum_ = false; |
| has_empty_prototype_ = true; |
| JSReceiver* first_non_empty_prototype; |
| for (PrototypeIterator iter(isolate_, *receiver_); !iter.IsAtEnd(); |
| iter.Advance()) { |
| JSReceiver* current = iter.GetCurrent<JSReceiver>(); |
| if (CheckAndInitalizeSimpleEnumCache(current)) continue; |
| has_empty_prototype_ = false; |
| first_non_empty_prototype = current; |
| // TODO(cbruni): use the first non-empty prototype. |
| USE(first_non_empty_prototype); |
| return; |
| } |
| DCHECK(has_empty_prototype_); |
| is_receiver_simple_enum_ = |
| receiver_->map()->EnumLength() != kInvalidEnumCacheSentinel && |
| !JSObject::cast(*receiver_)->HasEnumerableElements(); |
| } |
| |
| namespace { |
| |
| template <bool fast_properties> |
| Handle<FixedArray> GetOwnKeysWithElements(Isolate* isolate, |
| Handle<JSObject> object, |
| GetKeysConversion convert) { |
| Handle<FixedArray> keys; |
| ElementsAccessor* accessor = object->GetElementsAccessor(); |
| if (fast_properties) { |
| keys = JSObject::GetFastEnumPropertyKeys(isolate, object); |
| } else { |
| // TODO(cbruni): preallocate big enough array to also hold elements. |
| keys = JSObject::GetEnumPropertyKeys(object); |
| } |
| Handle<FixedArray> result = |
| accessor->PrependElementIndices(object, keys, convert, ONLY_ENUMERABLE); |
| |
| if (FLAG_trace_for_in_enumerate) { |
| PrintF("| strings=%d symbols=0 elements=%u || prototypes>=1 ||\n", |
| keys->length(), result->length() - keys->length()); |
| } |
| return result; |
| } |
| |
| MaybeHandle<FixedArray> GetOwnKeysWithUninitializedEnumCache( |
| Isolate* isolate, Handle<JSObject> object) { |
| // Uninitalized enum cache |
| Map* map = object->map(); |
| if (object->elements() != isolate->heap()->empty_fixed_array() || |
| object->elements() != isolate->heap()->empty_slow_element_dictionary()) { |
| // Assume that there are elements. |
| return MaybeHandle<FixedArray>(); |
| } |
| int number_of_own_descriptors = map->NumberOfOwnDescriptors(); |
| if (number_of_own_descriptors == 0) { |
| map->SetEnumLength(0); |
| return isolate->factory()->empty_fixed_array(); |
| } |
| // We have no elements but possibly enumerable property keys, hence we can |
| // directly initialize the enum cache. |
| return JSObject::GetFastEnumPropertyKeys(isolate, object); |
| } |
| |
| bool OnlyHasSimpleProperties(Map* map) { |
| return map->instance_type() > LAST_CUSTOM_ELEMENTS_RECEIVER; |
| } |
| |
| } // namespace |
| |
| MaybeHandle<FixedArray> FastKeyAccumulator::GetKeys(GetKeysConversion convert) { |
| Handle<FixedArray> keys; |
| if (GetKeysFast(convert).ToHandle(&keys)) { |
| return keys; |
| } |
| return GetKeysSlow(convert); |
| } |
| |
| MaybeHandle<FixedArray> FastKeyAccumulator::GetKeysFast( |
| GetKeysConversion convert) { |
| bool own_only = has_empty_prototype_ || type_ == OWN_ONLY; |
| Map* map = receiver_->map(); |
| if (!own_only || !OnlyHasSimpleProperties(map)) { |
| return MaybeHandle<FixedArray>(); |
| } |
| |
| // From this point on we are certiain to only collect own keys. |
| DCHECK(receiver_->IsJSObject()); |
| Handle<JSObject> object = Handle<JSObject>::cast(receiver_); |
| |
| // Do not try to use the enum-cache for dict-mode objects. |
| if (map->is_dictionary_map()) { |
| return GetOwnKeysWithElements<false>(isolate_, object, convert); |
| } |
| int enum_length = receiver_->map()->EnumLength(); |
| if (enum_length == kInvalidEnumCacheSentinel) { |
| Handle<FixedArray> keys; |
| // Try initializing the enum cache and return own properties. |
| if (GetOwnKeysWithUninitializedEnumCache(isolate_, object) |
| .ToHandle(&keys)) { |
| if (FLAG_trace_for_in_enumerate) { |
| PrintF("| strings=%d symbols=0 elements=0 || prototypes>=1 ||\n", |
| keys->length()); |
| } |
| is_receiver_simple_enum_ = |
| object->map()->EnumLength() != kInvalidEnumCacheSentinel; |
| return keys; |
| } |
| } |
| // The properties-only case failed because there were probably elements on the |
| // receiver. |
| return GetOwnKeysWithElements<true>(isolate_, object, convert); |
| } |
| |
| MaybeHandle<FixedArray> FastKeyAccumulator::GetKeysSlow( |
| GetKeysConversion convert) { |
| return JSReceiver::GetKeys(receiver_, type_, ENUMERABLE_STRINGS, KEEP_NUMBERS, |
| filter_proxy_keys_); |
| } |
| |
| } // namespace internal |
| } // namespace v8 |