Speedup JSReceiver::GetKeys

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index f547c8388cf9df637a2436ba64c4bd3342cbef7a..d81693d50c25f404386ebad0b4b6bdeddf7ca24f 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -2468,17 +2468,6 @@ class FixedArray: public FixedArrayBase {
 
   enum KeyFilter { ALL_KEYS, NON_SYMBOL_KEYS };
 
-  // Add the elements of a JSArray to this FixedArray.
-  MUST_USE_RESULT static MaybeHandle<FixedArray> AddKeysFromArrayLike(
-      Handle<FixedArray> content, Handle<JSObject> array,
-      KeyFilter filter = ALL_KEYS);
-
-  // Computes the union of keys and return the result.
-  // Used for implementing "for (n in object) { }"
-  MUST_USE_RESULT static MaybeHandle<FixedArray> UnionOfKeys(
-      Handle<FixedArray> first,
-      Handle<FixedArray> second);
-
   // Copy a sub array from the receiver to dest.
   void CopyTo(int pos, FixedArray* dest, int dest_pos, int len);
 
@@ -3572,6 +3561,7 @@ class ObjectHashTable: public HashTable<ObjectHashTable,
   Object* Lookup(Handle<Object> key);
   Object* Lookup(Handle<Object> key, int32_t hash);
   Object* Lookup(Isolate* isolate, Handle<Object> key, int32_t hash);
+  bool HasKey(Isolate* isolate, Handle<Object> key);
 
   // Adds (or overwrites) the value associated with the given key.
   static Handle<ObjectHashTable> Put(Handle<ObjectHashTable> table,
@@ -3580,6 +3570,13 @@ class ObjectHashTable: public HashTable<ObjectHashTable,
   static Handle<ObjectHashTable> Put(Handle<ObjectHashTable> table,
                                      Handle<Object> key, Handle<Object> value,
                                      int32_t hash);
+  static Handle<ObjectHashTable> Put(Isolate* isolate,
+                                     Handle<ObjectHashTable> table,
+                                     Handle<Object> key, Handle<Object> value);
+  static Handle<ObjectHashTable> Put(Isolate* isolate,
+                                     Handle<ObjectHashTable> table,
+                                     Handle<Object> key, Handle<Object> value,
+                                     int32_t hash);
 
   // Returns an ObjectHashTable (possibly |table|) where |key| has been removed.
   static Handle<ObjectHashTable> Remove(Handle<ObjectHashTable> table,
@@ -10470,6 +10467,30 @@ class BooleanBit : public AllStatic {
   }
 };
 
+
+class KeyAccumulator final BASE_EMBEDDED {

[Camillo Bruni, 2015/09/14 07:45:40]

I wasn't really sure where to put the class declaration

+ public:
+  explicit KeyAccumulator(Isolate* isolate)
+      : isolate_(isolate), keys_(), set_(), length_(0) {}

[Igor Sheludko, 2015/09/17 09:55:11]

keys_() and set_() are not really necessary here.

+
+  void AddKeys(Handle<FixedArray> array, FixedArray::KeyFilter filter);
+  void AddKeys(Handle<JSObject> array, FixedArray::KeyFilter filter);
+  Handle<FixedArray> GetKeys();
+  int GetLength();
+  bool HasKey(Handle<Object> key, int limit);
+  void AddKey(Handle<Object> key);
+  void PrepareForComparisons(int count);
+
+ private:
+  void EnsureCapacity(int capacity);
+  void Grow();
+
+  Isolate* isolate_;
+  Handle<FixedArray> keys_;
+  Handle<ObjectHashTable> set_;
+  int length_;
+  DISALLOW_COPY_AND_ASSIGN(KeyAccumulator);
+};
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_