1 // Copyright 2019 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 #ifndef V8_OBJECTS_JS_COLLECTION_ITERATOR_H_ 6 #define V8_OBJECTS_JS_COLLECTION_ITERATOR_H_ 7 8 #include "src/common/globals.h" 9 #include "src/objects/js-objects.h" 10 #include "src/objects/objects.h" 11 #include "src/objects/smi.h" 12 13 // Has to be the last include (doesn't have include guards): 14 #include "src/objects/object-macros.h" 15 16 namespace v8 { 17 namespace internal { 18 19 #include "torque-generated/src/objects/js-collection-iterator-tq.inc" 20 21 class JSCollectionIterator 22 : public TorqueGeneratedJSCollectionIterator<JSCollectionIterator, 23 JSObject> { 24 public: 25 void JSCollectionIteratorPrint(std::ostream& os, const char* name); 26 27 TQ_OBJECT_CONSTRUCTORS(JSCollectionIterator) 28 }; 29 30 // OrderedHashTableIterator is an iterator that iterates over the keys and 31 // values of an OrderedHashTable. 32 // 33 // The iterator has a reference to the underlying OrderedHashTable data, 34 // [table], as well as the current [index] the iterator is at. 35 // 36 // When the OrderedHashTable is rehashed it adds a reference from the old table 37 // to the new table as well as storing enough data about the changes so that the 38 // iterator [index] can be adjusted accordingly. 39 // 40 // When the [Next] result from the iterator is requested, the iterator checks if 41 // there is a newer table that it needs to transition to. 42 template <class Derived, class TableType> 43 class OrderedHashTableIterator : public JSCollectionIterator { 44 public: 45 // Whether the iterator has more elements. This needs to be called before 46 // calling |CurrentKey| and/or |CurrentValue|. 47 bool HasMore(); 48 49 // Move the index forward one. MoveNext()50 void MoveNext() { set_index(Smi::FromInt(Smi::ToInt(index()) + 1)); } 51 52 // Returns the current key of the iterator. This should only be called when 53 // |HasMore| returns true. 54 inline Object CurrentKey(); 55 56 private: 57 // Transitions the iterator to the non obsolete backing store. This is a NOP 58 // if the [table] is not obsolete. 59 void Transition(); 60 61 OBJECT_CONSTRUCTORS(OrderedHashTableIterator, JSCollectionIterator); 62 }; 63 64 } // namespace internal 65 } // namespace v8 66 67 #include "src/objects/object-macros-undef.h" 68 69 #endif // V8_OBJECTS_JS_COLLECTION_ITERATOR_H_ 70