Rewrite GetAccessor using the LookupIterator

src/objects.cc

 // Copyright 2013 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.
 
 #include "src/v8.h"
 
 #include "src/accessors.h"
 #include "src/allocation-site-scopes.h"
 #include "src/api.h"
 #include "src/arguments.h"
@@ skipping 6562 matching lines @@
 
 MaybeHandle<Object> JSObject::GetAccessor(Handle<JSObject> object,
                                           Handle<Name> name,
                                           AccessorComponent component) {
   Isolate* isolate = object->GetIsolate();
 
   // Make sure that the top context does not change when doing callbacks or
   // interceptor calls.
   AssertNoContextChange ncc(isolate);
 
-  // Check access rights if needed.
-  if (object->IsAccessCheckNeeded() &&
-      !isolate->MayNamedAccess(object, name, v8::ACCESS_HAS)) {
-    isolate->ReportFailedAccessCheck(object, v8::ACCESS_HAS);
-    RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
-    return isolate->factory()->undefined_value();
-  }
-
   // Make the lookup and include prototypes.
   uint32_t index = 0;
   if (name->AsArrayIndex(&index)) {
     for (PrototypeIterator iter(isolate, object,
                                 PrototypeIterator::START_AT_RECEIVER);
          !iter.IsAtEnd(); iter.Advance()) {
-      if (PrototypeIterator::GetCurrent(iter)->IsJSObject() &&
-          JSObject::cast(*PrototypeIterator::GetCurrent(iter))
-              ->HasDictionaryElements()) {
-        JSObject* js_object =
-            JSObject::cast(*PrototypeIterator::GetCurrent(iter));
+      Handle<Object> current = PrototypeIterator::GetCurrent(iter);
+      // Check access rights if needed.
+      if (current->IsAccessCheckNeeded() &&
+          !isolate->MayNamedAccess(Handle<JSObject>::cast(current), name,
+                                   v8::ACCESS_HAS)) {
+        isolate->ReportFailedAccessCheck(Handle<JSObject>::cast(current),
+                                         v8::ACCESS_HAS);
+        RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
+        return isolate->factory()->undefined_value();
+      }
+
+      if (current->IsJSObject() &&
+          Handle<JSObject>::cast(current)->HasDictionaryElements()) {
+        JSObject* js_object = JSObject::cast(*current);
         SeededNumberDictionary* dictionary = js_object->element_dictionary();
         int entry = dictionary->FindEntry(index);
         if (entry != SeededNumberDictionary::kNotFound) {
           Object* element = dictionary->ValueAt(entry);
           if (dictionary->DetailsAt(entry).type() == CALLBACKS &&
               element->IsAccessorPair()) {
             return handle(AccessorPair::cast(element)->GetComponent(component),
                           isolate);
           }
         }
       }
     }
   } else {
-    for (PrototypeIterator iter(isolate, object,
-                                PrototypeIterator::START_AT_RECEIVER);
-         !iter.IsAtEnd(); iter.Advance()) {
-      LookupResult result(isolate);
-      JSReceiver::cast(*PrototypeIterator::GetCurrent(iter))
-          ->LookupOwn(name, &result);
-      if (result.IsFound()) {
-        if (result.IsReadOnly()) return isolate->factory()->undefined_value();
-        if (result.IsPropertyCallbacks()) {
-          Object* obj = result.GetCallbackObject();
-          if (obj->IsAccessorPair()) {
-            return handle(AccessorPair::cast(obj)->GetComponent(component),
-                          isolate);
+    LookupIterator it(object, name,
+                      LookupIterator::CHECK_DERIVED_SKIP_INTERCEPTOR);
+    for (; it.IsFound(); it.Next()) {
+      switch (it.state()) {
+        case LookupIterator::NOT_FOUND:
+        case LookupIterator::INTERCEPTOR:
+          UNREACHABLE();
+
+        case LookupIterator::ACCESS_CHECK:
+          if (it.HasAccess(v8::ACCESS_HAS)) continue;
+          isolate->ReportFailedAccessCheck(it.GetHolder<JSObject>(),
+                                           v8::ACCESS_HAS);
+          RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
+          return isolate->factory()->undefined_value();
+
+        case LookupIterator::JSPROXY:
+          return isolate->factory()->undefined_value();
+
+        case LookupIterator::PROPERTY:
+          if (!it.HasProperty()) continue;
+          switch (it.property_kind()) {
+            case LookupIterator::DATA:
+              continue;
+            case LookupIterator::ACCESSOR: {
+              Handle<Object> maybe_pair = it.GetAccessors();
+              if (maybe_pair->IsAccessorPair()) {
+                return handle(
+                    AccessorPair::cast(*maybe_pair)->GetComponent(component),
+                    isolate);
+              }
+            }
           }
-        }
       }
     }
   }
   return isolate->factory()->undefined_value();
 }
 
 
 Object* JSObject::SlowReverseLookup(Object* value) {
   if (HasFastProperties()) {
     int number_of_own_descriptors = map()->NumberOfOwnDescriptors();
@@ skipping 10007 matching lines @@
 #define ERROR_MESSAGES_TEXTS(C, T) T,
   static const char* error_messages_[] = {
       ERROR_MESSAGES_LIST(ERROR_MESSAGES_TEXTS)
   };
 #undef ERROR_MESSAGES_TEXTS
   return error_messages_[reason];
 }
 
 
 } }  // namespace v8::internal