Fix for-in for large indexes and indexes on proxies

src/objects-inl.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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 257 matching lines @@
 }
 
 
 bool Object::HasValidElements() {
   // Dictionary is covered under FixedArray.
   return IsFixedArray() || IsFixedDoubleArray() || IsExternalArray() ||
          IsFixedTypedArrayBase();
 }
 
 
+bool Object::KeyEquals(Object* second) {
+  Object* first = this;
+  if (second->IsNumber()) {
+    if (first->IsNumber()) return first->Number() == second->Number();
+    Object* temp = first;
+    first = second;
+    second = temp;
+  }
+  if (first->IsNumber()) {
+    DCHECK_LE(0, first->Number());
+    uint32_t expected = static_cast<uint32_t>(first->Number());
+    uint32_t index;
+    return Name::cast(second)->AsArrayIndex(&index) && index == expected;
+  }
+  return Name::cast(first)->Equals(Name::cast(second));
+}
+
+
 Handle<Object> Object::NewStorageFor(Isolate* isolate,
                                      Handle<Object> object,
                                      Representation representation) {
   if (representation.IsSmi() && object->IsUninitialized()) {
     return handle(Smi::FromInt(0), isolate);
   }
   if (!representation.IsDouble()) return object;
   double value;
   if (object->IsUninitialized()) {
     value = 0;
@@ skipping 7326 matching lines @@
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_