Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2013 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/key-accumulator.h" |
| 6 | |
| 7 | #include "src/elements.h" |
| 8 | #include "src/factory.h" |
| 9 | #include "src/isolate-inl.h" |
| 10 | #include "src/objects-inl.h" |
| 11 | #include "src/property-descriptor.h" |
| 12 | |
| 13 | |
| 14 | namespace v8 { |
| 15 | namespace internal { |
| 16 | |
| 17 | |
| 18 | KeyAccumulator::~KeyAccumulator() { |
| 19 | for (size_t i = 0; i < elements_.size(); i++) { |
| 20 | delete elements_[i]; |
| 21 | } |
| 22 | } |
| 23 | |
| 24 | |
| 25 | Handle<FixedArray> KeyAccumulator::GetKeys(GetKeysConversion convert) { |
| 26 | if (length_ == 0) { |
| 27 | return isolate_->factory()->empty_fixed_array(); |
| 28 | } |
| 29 | // Make sure we have all the lengths collected. |
| 30 | NextPrototype(); |
| 31 | |
| 32 | // Assemble the result array by first adding the element keys and then the |
| 33 | // property keys. We use the total number of String + Symbol keys per level in |
| 34 | // |level_lengths_| and the available element keys in the corresponding bucket |
| 35 | // in |elements_| to deduce the number of keys to take from the |
| 36 | // |string_properties_| and |symbol_properties_| set. |
| 37 | Handle<FixedArray> result = isolate_->factory()->NewFixedArray(length_); |
| 38 | int insertion_index = 0; |
| 39 | int string_properties_index = 0; |
| 40 | int symbol_properties_index = 0; |
| 41 | // String and Symbol lengths always come in pairs: |
| 42 | size_t max_level = level_lengths_.size() / 2; |
| 43 | for (size_t level = 0; level < max_level; level++) { |
| 44 | int num_string_properties = level_lengths_[level * 2]; |
| 45 | int num_symbol_properties = level_lengths_[level * 2 + 1]; |
| 46 | if (num_string_properties < 0) { |
| 47 | // If the |num_string_properties| is negative, the current level contains |
| 48 | // properties from a proxy, hence we skip the integer keys in |elements_| |
| 49 | // since proxies define the complete ordering. |
| 50 | num_string_properties = -num_string_properties; |
| 51 | } else if (level < elements_.size()) { |
| 52 | // Add the element indices for this prototype level. |
| 53 | std::vector<uint32_t>* elements = elements_[level]; |
| 54 | int num_elements = static_cast<int>(elements->size()); |
| 55 | for (int i = 0; i < num_elements; i++) { |
| 56 | Handle<Object> key; |
| 57 | if (convert == KEEP_NUMBERS) { |
| 58 | key = isolate_->factory()->NewNumberFromUint(elements->at(i)); |
| 59 | } else { |
| 60 | key = isolate_->factory()->Uint32ToString(elements->at(i)); |
| 61 | } |
| 62 | result->set(insertion_index, *key); |
| 63 | insertion_index++; |
| 64 | } |
| 65 | } |
| 66 | // Add the string property keys for this prototype level. |
| 67 | for (int i = 0; i < num_string_properties; i++) { |
| 68 | Object* key = string_properties_->KeyAt(string_properties_index); |
| 69 | result->set(insertion_index, key); |
| 70 | insertion_index++; |
| 71 | string_properties_index++; |
| 72 | } |
| 73 | // Add the symbol property keys for this prototype level. |
| 74 | for (int i = 0; i < num_symbol_properties; i++) { |
| 75 | Object* key = symbol_properties_->KeyAt(symbol_properties_index); |
| 76 | result->set(insertion_index, key); |
| 77 | insertion_index++; |
| 78 | symbol_properties_index++; |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | DCHECK_EQ(insertion_index, length_); |
| 83 | return result; |
| 84 | } |
| 85 | |
| 86 | |
| 87 | namespace { |
| 88 | |
| 89 | bool AccumulatorHasKey(std::vector<uint32_t>* sub_elements, uint32_t key) { |
| 90 | return std::binary_search(sub_elements->begin(), sub_elements->end(), key); |
| 91 | } |
| 92 | |
| 93 | } // namespace |
| 94 | |
| 95 | bool KeyAccumulator::AddKey(Object* key, AddKeyConversion convert) { |
| 96 | return AddKey(handle(key, isolate_), convert); |
| 97 | } |
| 98 | |
| 99 | |
| 100 | bool KeyAccumulator::AddKey(Handle<Object> key, AddKeyConversion convert) { |
| 101 | if (key->IsSymbol()) { |
| 102 | if (filter_ & SKIP_SYMBOLS) return false; |
| 103 | if (Handle<Symbol>::cast(key)->is_private()) return false; |
| 104 | return AddSymbolKey(key); |
| 105 | } |
| 106 | if (filter_ & SKIP_STRINGS) return false; |
| 107 | // Make sure we do not add keys to a proxy-level (see AddKeysFromProxy). |
| 108 | DCHECK_LE(0, level_string_length_); |
| 109 | // In some cases (e.g. proxies) we might get in String-converted ints which |
| 110 | // should be added to the elements list instead of the properties. For |
| 111 | // proxies we have to convert as well but also respect the original order. |
| 112 | // Therefore we add a converted key to both sides |
| 113 | if (convert == CONVERT_TO_ARRAY_INDEX || convert == PROXY_MAGIC) { |
| 114 | uint32_t index = 0; |
| 115 | int prev_length = length_; |
| 116 | int prev_proto = level_string_length_; |
| 117 | if ((key->IsString() && Handle<String>::cast(key)->AsArrayIndex(&index)) || |
| 118 | key->ToArrayIndex(&index)) { |
| 119 | bool key_was_added = AddIntegerKey(index); |
| 120 | if (convert == CONVERT_TO_ARRAY_INDEX) return key_was_added; |
| 121 | if (convert == PROXY_MAGIC) { |
| 122 | // If we had an array index (number) and it wasn't added, the key |
| 123 | // already existed before, hence we cannot add it to the properties |
| 124 | // keys as it would lead to duplicate entries. |
| 125 | if (!key_was_added) { |
| 126 | return false; |
| 127 | } |
| 128 | length_ = prev_length; |
| 129 | level_string_length_ = prev_proto; |
| 130 | } |
| 131 | } |
| 132 | } |
| 133 | return AddStringKey(key, convert); |
| 134 | } |
| 135 | |
| 136 | |
| 137 | bool KeyAccumulator::AddKey(uint32_t key) { return AddIntegerKey(key); } |
| 138 | |
| 139 | |
| 140 | bool KeyAccumulator::AddIntegerKey(uint32_t key) { |
| 141 | // Make sure we do not add keys to a proxy-level (see AddKeysFromProxy). |
| 142 | // We mark proxy-levels with a negative length |
| 143 | DCHECK_LE(0, level_string_length_); |
| 144 | // Binary search over all but the last level. The last one might not be |
| 145 | // sorted yet. |
| 146 | for (size_t i = 1; i < elements_.size(); i++) { |
| 147 | if (AccumulatorHasKey(elements_[i - 1], key)) return false; |
| 148 | } |
| 149 | elements_.back()->push_back(key); |
| 150 | length_++; |
| 151 | return true; |
| 152 | } |
| 153 | |
| 154 | |
| 155 | bool KeyAccumulator::AddStringKey(Handle<Object> key, |
| 156 | AddKeyConversion convert) { |
| 157 | if (string_properties_.is_null()) { |
| 158 | string_properties_ = OrderedHashSet::Allocate(isolate_, 16); |
| 159 | } |
| 160 | // TODO(cbruni): remove this conversion once we throw the correct TypeError |
| 161 | // for non-string/symbol elements returned by proxies |
| 162 | if (convert == PROXY_MAGIC && key->IsNumber()) { |
| 163 | key = isolate_->factory()->NumberToString(key); |
| 164 | } |
| 165 | int prev_size = string_properties_->NumberOfElements(); |
| 166 | string_properties_ = OrderedHashSet::Add(string_properties_, key); |
| 167 | if (prev_size < string_properties_->NumberOfElements()) { |
| 168 | length_++; |
| 169 | level_string_length_++; |
| 170 | return true; |
| 171 | } else { |
| 172 | return false; |
| 173 | } |
| 174 | } |
| 175 | |
| 176 | |
| 177 | bool KeyAccumulator::AddSymbolKey(Handle<Object> key) { |
| 178 | if (symbol_properties_.is_null()) { |
| 179 | symbol_properties_ = OrderedHashSet::Allocate(isolate_, 16); |
| 180 | } |
| 181 | int prev_size = symbol_properties_->NumberOfElements(); |
| 182 | symbol_properties_ = OrderedHashSet::Add(symbol_properties_, key); |
| 183 | if (prev_size < symbol_properties_->NumberOfElements()) { |
| 184 | length_++; |
| 185 | level_symbol_length_++; |
| 186 | return true; |
| 187 | } else { |
| 188 | return false; |
| 189 | } |
| 190 | } |
| 191 | |
| 192 | |
| 193 | void KeyAccumulator::AddKeys(Handle<FixedArray> array, |
| 194 | AddKeyConversion convert) { |
| 195 | int add_length = array->length(); |
| 196 | if (add_length == 0) return; |
| 197 | for (int i = 0; i < add_length; i++) { |
| 198 | Handle<Object> current(array->get(i), isolate_); |
| 199 | AddKey(current, convert); |
| 200 | } |
| 201 | } |
| 202 | |
| 203 | |
| 204 | void KeyAccumulator::AddKeys(Handle<JSObject> array_like, |
| 205 | AddKeyConversion convert) { |
| 206 | DCHECK(array_like->IsJSArray() || array_like->HasSloppyArgumentsElements()); |
| 207 | ElementsAccessor* accessor = array_like->GetElementsAccessor(); |
| 208 | accessor->AddElementsToKeyAccumulator(array_like, this, convert); |
| 209 | } |
| 210 | |
| 211 | |
| 212 | void KeyAccumulator::AddKeysFromProxy(Handle<JSObject> array_like) { |
| 213 | // Proxies define a complete list of keys with no distinction of |
| 214 | // elements and properties, which breaks the normal assumption for the |
| 215 | // KeyAccumulator. |
| 216 | AddKeys(array_like, PROXY_MAGIC); |
| 217 | // Invert the current length to indicate a present proxy, so we can ignore |
| 218 | // element keys for this level. Otherwise we would not fully respect the order |
| 219 | // given by the proxy. |
| 220 | level_string_length_ = -level_string_length_; |
| 221 | } |
| 222 | |
| 223 | |
| 224 | MaybeHandle<FixedArray> FilterProxyKeys(Isolate* isolate, Handle<JSProxy> owner, |
| 225 | Handle<FixedArray> keys, |
| 226 | PropertyFilter filter) { |
| 227 | if (filter == ALL_PROPERTIES) { |
| 228 | // Nothing to do. |
| 229 | return keys; |
| 230 | } |
| 231 | int store_position = 0; |
| 232 | for (int i = 0; i < keys->length(); ++i) { |
| 233 | Handle<Name> key(Name::cast(keys->get(i)), isolate); |
| 234 | if (key->FilterKey(filter)) continue; // Skip this key. |
| 235 | if (filter & ONLY_ENUMERABLE) { |
| 236 | PropertyDescriptor desc; |
| 237 | Maybe<bool> found = |
| 238 | JSProxy::GetOwnPropertyDescriptor(isolate, owner, key, &desc); |
| 239 | MAYBE_RETURN(found, MaybeHandle<FixedArray>()); |
| 240 | if (!found.FromJust() || !desc.enumerable()) continue; // Skip this key. |
| 241 | } |
| 242 | // Keep this key. |
| 243 | if (store_position != i) { |
| 244 | keys->set(store_position, *key); |
| 245 | } |
| 246 | store_position++; |
| 247 | } |
| 248 | if (store_position == 0) return isolate->factory()->empty_fixed_array(); |
| 249 | keys->Shrink(store_position); |
| 250 | return keys; |
| 251 | } |
| 252 | |
| 253 | |
| 254 | // Returns "nothing" in case of exception, "true" on success. |
| 255 | Maybe<bool> KeyAccumulator::AddKeysFromProxy(Handle<JSProxy> proxy, |
| 256 | Handle<FixedArray> keys) { |
| 257 | ASSIGN_RETURN_ON_EXCEPTION_VALUE( |
| 258 | isolate_, keys, FilterProxyKeys(isolate_, proxy, keys, filter_), |
| 259 | Nothing<bool>()); |
| 260 | // Proxies define a complete list of keys with no distinction of |
| 261 | // elements and properties, which breaks the normal assumption for the |
| 262 | // KeyAccumulator. |
| 263 | AddKeys(keys, PROXY_MAGIC); |
| 264 | // Invert the current length to indicate a present proxy, so we can ignore |
| 265 | // element keys for this level. Otherwise we would not fully respect the order |
| 266 | // given by the proxy. |
| 267 | level_string_length_ = -level_string_length_; |
| 268 | return Just(true); |
| 269 | } |
| 270 | |
| 271 | |
| 272 | void KeyAccumulator::AddElementKeysFromInterceptor( |
| 273 | Handle<JSObject> array_like) { |
| 274 | AddKeys(array_like, CONVERT_TO_ARRAY_INDEX); |
| 275 | // The interceptor might introduce duplicates for the current level, since |
| 276 | // these keys get added after the objects's normal element keys. |
| 277 | SortCurrentElementsListRemoveDuplicates(); |
| 278 | } |
| 279 | |
| 280 | |
| 281 | void KeyAccumulator::SortCurrentElementsListRemoveDuplicates() { |
| 282 | // Sort and remove duplicates from the current elements level and adjust. |
| 283 | // the lengths accordingly. |
| 284 | auto last_level = elements_.back(); |
| 285 | size_t nof_removed_keys = last_level->size(); |
| 286 | std::sort(last_level->begin(), last_level->end()); |
| 287 | last_level->erase(std::unique(last_level->begin(), last_level->end()), |
| 288 | last_level->end()); |
| 289 | // Adjust total length by the number of removed duplicates. |
| 290 | nof_removed_keys -= last_level->size(); |
| 291 | length_ -= static_cast<int>(nof_removed_keys); |
| 292 | } |
| 293 | |
| 294 | |
| 295 | void KeyAccumulator::SortCurrentElementsList() { |
| 296 | if (elements_.empty()) return; |
| 297 | auto element_keys = elements_.back(); |
| 298 | std::sort(element_keys->begin(), element_keys->end()); |
| 299 | } |
| 300 | |
| 301 | |
| 302 | void KeyAccumulator::NextPrototype() { |
| 303 | // Store the protoLength on the first call of this method. |
| 304 | if (!elements_.empty()) { |
| 305 | level_lengths_.push_back(level_string_length_); |
| 306 | level_lengths_.push_back(level_symbol_length_); |
| 307 | } |
| 308 | elements_.push_back(new std::vector<uint32_t>()); |
| 309 | level_string_length_ = 0; |
| 310 | level_symbol_length_ = 0; |
| 311 | } |
| 312 | |
| 313 | |
| 314 | } // namespace internal |
| 315 | } // namespace v8 |