Rossberg's suggested changes to the LookupIterator.

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"
 
 namespace v8 {
 namespace internal {
 
 class LookupIterator V8_FINAL BASE_EMBEDDED {
  public:
-  enum Type {
+  enum Configuration {
     CHECK_DERIVED      = 1 << 0,
     CHECK_INTERCEPTOR  = 1 << 1,
     CHECK_ACCESS_CHECK = 1 << 2,
     CHECK_OWN_REAL     = 0,
     CHECK_ALL          = CHECK_DERIVED | CHECK_INTERCEPTOR | CHECK_ACCESS_CHECK,
     SKIP_INTERCEPTOR   = CHECK_ALL ^ CHECK_INTERCEPTOR
   };
 
   enum State {
     NOT_FOUND,
     PROPERTY,
     INTERCEPTOR,
     ACCESS_CHECK,
     JSPROXY
   };
 
-  enum PropertyType {
+  enum PropertyKind {
     DATA,
-    ACCESSORS
+    ACCESSOR
   };
 
   enum PropertyEncoding {
     DICTIONARY,
     DESCRIPTOR
   };
 
   LookupIterator(Handle<Object> receiver,
                  Handle<Name> name,
-                 Type type = CHECK_ALL)
-      : type_(type),
+                 Configuration configuration = CHECK_ALL)
+      : configuration_(configuration),
         state_(NOT_FOUND),
-        property_type_(DATA),
+        property_kind_(DATA),
         property_encoding_(DESCRIPTOR),
         property_details_(NONE, NONEXISTENT, Representation::None()),
         isolate_(name->GetIsolate()),
         name_(name),
         maybe_receiver_(receiver),
         number_(DescriptorArray::kNotFound) {
-    Handle<JSReceiver> origin = GetOrigin();
+    Handle<JSReceiver> origin = GetRoot();
     holder_map_ = handle(origin->map());
     maybe_holder_ = origin;
     Next();
   }
 
   LookupIterator(Handle<Object> receiver,
                  Handle<Name> name,
                  Handle<JSReceiver> holder,
-                 Type type = CHECK_ALL)
-      : type_(type),
+                 Configuration configuration = CHECK_ALL)
+      : configuration_(configuration),
         state_(NOT_FOUND),
-        property_type_(DATA),
+        property_kind_(DATA),
         property_encoding_(DESCRIPTOR),
         property_details_(NONE, NONEXISTENT, Representation::None()),
         isolate_(name->GetIsolate()),
         name_(name),
         holder_map_(holder->map()),
         maybe_receiver_(receiver),
         maybe_holder_(holder),
         number_(DescriptorArray::kNotFound) {
     Next();
   }
 
   Isolate* isolate() const { return isolate_; }
   State state() const { return state_; }
   Handle<Name> name() const { return name_; }
 
   bool IsFound() const { return state_ != NOT_FOUND; }
   void Next();
 
   Heap* heap() const { return isolate_->heap(); }
   Factory* factory() const { return isolate_->factory(); }
   Handle<Object> GetReceiver() const {
     return Handle<Object>::cast(maybe_receiver_.ToHandleChecked());
   }
   Handle<JSObject> GetHolder() const {
     ASSERT(IsFound() && state_ != JSPROXY);
     return Handle<JSObject>::cast(maybe_holder_.ToHandleChecked());
   }
-  Handle<JSReceiver> GetOrigin() const;
+  Handle<JSReceiver> GetRoot() const;
 
   /* ACCESS_CHECK */
   bool HasAccess(v8::AccessType access_type) const;
 
   /* PROPERTY */
   // HasProperty needs to be called before any of the other PROPERTY methods
   // below can be used. It ensures that we are able to provide a definite
   // answer, and loads extra information about the property.
   bool HasProperty();
-  PropertyType property_type() const {
+  PropertyKind property_kind() const {
     ASSERT(has_property_);
-    return property_type_;
+    return property_kind_;
   }
   PropertyDetails property_details() const {
     ASSERT(has_property_);
     return property_details_;
   }
   Handle<Object> GetAccessors() const;
   Handle<Object> GetDataValue() const;
 
   /* JSPROXY */
 
   Handle<JSProxy> GetJSProxy() const {
     return Handle<JSProxy>::cast(maybe_holder_.ToHandleChecked());
   }
 
  private:
   Handle<Map> GetReceiverMap() const;
 
   MUST_USE_RESULT bool NextHolder();
-  void LookupInHolder();
+  State LookupInHolder();
   Handle<Object> FetchValue() const;
 
   bool IsBootstrapping() const;
 
   // Methods that fetch data from the holder ensure they always have a holder.
   // This means the receiver needs to be present as opposed to just the receiver
   // map. Other objects in the prototype chain are transitively guaranteed to be
   // present via the receiver map.
   bool is_guaranteed_to_have_holder() const {
     return !maybe_receiver_.is_null();
   }
   bool check_interceptor() const {
-    return !IsBootstrapping() && (type_ & CHECK_INTERCEPTOR) != 0;
+    return !IsBootstrapping() && (configuration_ & CHECK_INTERCEPTOR) != 0;
   }
   bool check_derived() const {
-    return (type_ & CHECK_DERIVED) != 0;
+    return (configuration_ & CHECK_DERIVED) != 0;
   }
   bool check_access_check() const {
-    return (type_ & CHECK_ACCESS_CHECK) != 0;
+    return (configuration_ & CHECK_ACCESS_CHECK) != 0;
   }
 
-  Type type_;
+  Configuration configuration_;
   State state_;
   bool has_property_;
-  PropertyType property_type_;
+  PropertyKind property_kind_;
   PropertyEncoding property_encoding_;
   PropertyDetails property_details_;
   Isolate* isolate_;
   Handle<Name> name_;
   Handle<Map> holder_map_;
   MaybeHandle<Object> maybe_receiver_;
   MaybeHandle<JSReceiver> maybe_holder_;
 
   int number_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_LOOKUP_H_