handle the special snowflakes that are Integer Indexed Exotic objects

src/lookup.h

 // Copyright 2014 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_LOOKUP_H_
 #define V8_LOOKUP_H_
 
 #include "src/factory.h"
 #include "src/isolate.h"
 #include "src/objects.h"
@@ skipping 13 matching lines @@
     OWN_SKIP_INTERCEPTOR = 0,
     OWN = kInterceptor,
     HIDDEN_SKIP_INTERCEPTOR = kHidden,
     HIDDEN = kHidden | kInterceptor,
     PROTOTYPE_CHAIN_SKIP_INTERCEPTOR = kHidden | kPrototypeChain,
     PROTOTYPE_CHAIN = kHidden | kPrototypeChain | kInterceptor
   };
 
   enum State {
     ACCESS_CHECK,
+    INTEGER_INDEXED_EXOTIC,
     INTERCEPTOR,
     JSPROXY,
     NOT_FOUND,
     ACCESSOR,
     DATA,
     TRANSITION,
     // Set state_ to BEFORE_PROPERTY to ensure that the next lookup will be a
     // PROPERTY lookup.
     BEFORE_PROPERTY = INTERCEPTOR
   };
 
   LookupIterator(Handle<Object> receiver, Handle<Name> name,
                  Configuration configuration = PROTOTYPE_CHAIN)
       : configuration_(ComputeConfiguration(configuration, name)),
         state_(NOT_FOUND),
+        exotic_index_state_(ExoticIndexState::kUninitialized),
         property_details_(NONE, v8::internal::DATA, 0),
         isolate_(name->GetIsolate()),
         name_(name),
         receiver_(receiver),
         number_(DescriptorArray::kNotFound) {
     holder_ = GetRoot();
     holder_map_ = handle(holder_->map(), isolate_);
     Next();
   }
 
   LookupIterator(Handle<Object> receiver, Handle<Name> name,
                  Handle<JSReceiver> holder,
                  Configuration configuration = PROTOTYPE_CHAIN)
       : configuration_(ComputeConfiguration(configuration, name)),
         state_(NOT_FOUND),
+        exotic_index_state_(ExoticIndexState::kUninitialized),
         property_details_(NONE, v8::internal::DATA, 0),
         isolate_(name->GetIsolate()),
         name_(name),
         holder_map_(holder->map(), isolate_),
         receiver_(receiver),
         holder_(holder),
         number_(DescriptorArray::kNotFound) {
     Next();
   }
 
@@ skipping 59 matching lines @@
   Handle<PropertyCell> GetPropertyCell() const;
   Handle<PropertyCell> GetTransitionPropertyCell() const {
     DCHECK_EQ(TRANSITION, state_);
     return Handle<PropertyCell>::cast(transition_);
   }
   Handle<Object> GetAccessors() const;
   Handle<Object> GetDataValue() const;
   // Usually returns the value that was passed in, but may perform
   // non-observable modifications on it, such as internalize strings.
   Handle<Object> WriteDataValue(Handle<Object> value);
-
-  // Checks whether the receiver is an indexed exotic object
-  // and name is a special numeric index.
-  bool IsSpecialNumericIndex() const;
-
   void InternalizeName();
 
  private:
   Handle<Map> GetReceiverMap() const;
 
   MUST_USE_RESULT inline JSReceiver* NextHolder(Map* map);
   inline State LookupInHolder(Map* map, JSReceiver* holder);
   Handle<Object> FetchValue() const;
   void ReloadPropertyInformation();
 
@@ skipping 20 matching lines @@
   static Configuration ComputeConfiguration(
       Configuration configuration, Handle<Name> name) {
     if (name->IsOwn()) {
       return static_cast<Configuration>(configuration &
                                         HIDDEN_SKIP_INTERCEPTOR);
     } else {
       return configuration;
     }
   }
 
+  enum class ExoticIndexState { kUninitialized, kNoIndex, kIndex };
+  bool IsIntegerIndexedExotic(JSReceiver* holder);
+
   // If configuration_ becomes mutable, update
   // HolderIsReceiverOrHiddenPrototype.
   Configuration configuration_;
   State state_;
   bool has_property_;
+  ExoticIndexState exotic_index_state_;
   PropertyDetails property_details_;
   Isolate* isolate_;
   Handle<Name> name_;
   Handle<Map> holder_map_;
   Handle<Object> transition_;
   Handle<Object> receiver_;
   Handle<JSReceiver> holder_;
 
   int number_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_LOOKUP_H_