Speedup JSReceiver::GetKeys

src/objects.h

 // Copyright 2012 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.
 
 #ifndef V8_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 2450 matching lines @@
   // Gives access to raw memory which stores the array's data.
   inline Object** data_start();
 
   inline void FillWithHoles(int from, int to);
 
   // Shrink length and insert filler objects.
   void Shrink(int length);
 
   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);
 
   // Garbage collection support.
   static int SizeFor(int length) { return kHeaderSize + length * kPointerSize; }
 
   // Code Generation support.
   static int OffsetOfElementAt(int index) { return SizeFor(index); }
 
   // Garbage collection support.
@@ skipping 1073 matching lines @@
   // Attempt to shrink hash table after removal of key.
   MUST_USE_RESULT static inline Handle<ObjectHashTable> Shrink(
       Handle<ObjectHashTable> table,
       Handle<Object> key);
 
   // Looks up the value associated with the given key. The hole value is
   // returned in case the key is not present.
   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,
                                      Handle<Object> key,
                                      Handle<Object> value);
   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,
                                         Handle<Object> key,
                                         bool* was_present);
   static Handle<ObjectHashTable> Remove(Handle<ObjectHashTable> table,
                                         Handle<Object> key, bool* was_present,
                                         int32_t hash);
 
  protected:
@@ skipping 6870 matching lines @@
   static inline int set(int value, int bit_position, bool v) {
     if (v) {
       value |= (1 << bit_position);
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
+
+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_