Skip the context extension object when locating objects referenced from anoth...

src/runtime.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5718 matching lines @@
   Handle<JSObject> result = Factory::NewJSObject(Top::array_function());
   Handle<JSArray>::cast(result)->SetContent(*instances);
   return *result;
 }
 
 
 // Helper function used by Runtime_DebugReferencedBy below.
 static int DebugReferencedBy(JSObject* target,
                              Object* instance_filter, int max_references,
                              FixedArray* instances, int instances_size,
-                             JSFunction* context_extension_function,
                              JSFunction* arguments_function) {
   NoHandleAllocation ha;
   AssertNoAllocation no_alloc;
 
   // Iterate the heap.
   int count = 0;
   JSObject* last = NULL;
   HeapIterator iterator;
   while (iterator.has_next() &&
          (max_references == 0 || count < max_references)) {
     // Only look at all JSObjects.
     HeapObject* heap_obj = iterator.next();
     if (heap_obj->IsJSObject()) {
       // Skip context extension objects and argument arrays as these are
       // checked in the context of functions using them.
       JSObject* obj = JSObject::cast(heap_obj);
-      if (obj->map()->constructor() == context_extension_function ||
+      if (obj->IsJSContextExtensionObject() ||
           obj->map()->constructor() == arguments_function) {
         continue;
       }
 
       // Check if the JS object has a reference to the object looked for.
       if (obj->ReferencesObject(target)) {
         // Check instance filter if supplied. This is normally used to avoid
         // references from mirror objects (see Runtime_IsInPrototypeChain).
         if (!instance_filter->IsUndefined()) {
           Object* V = obj;
@@ skipping 48 matching lines @@
 
   // Check parameters.
   CONVERT_CHECKED(JSObject, target, args[0]);
   Object* instance_filter = args[1];
   RUNTIME_ASSERT(instance_filter->IsUndefined() ||
                  instance_filter->IsJSObject());
   CONVERT_NUMBER_CHECKED(int32_t, max_references, Int32, args[2]);
   RUNTIME_ASSERT(max_references >= 0);
 
   // Get the constructor function for context extension and arguments array.
-  JSFunction* context_extension_function =
-      Top::context()->global_context()->context_extension_function();
   JSObject* arguments_boilerplate =
       Top::context()->global_context()->arguments_boilerplate();
   JSFunction* arguments_function =
       JSFunction::cast(arguments_boilerplate->map()->constructor());
 
   // Get the number of referencing objects.
   int count;
   count = DebugReferencedBy(target, instance_filter, max_references,
-                            NULL, 0,
-                            context_extension_function, arguments_function);
+                            NULL, 0, arguments_function);
 
   // Allocate an array to hold the result.
   Object* object = Heap::AllocateFixedArray(count);
   if (object->IsFailure()) return object;
   FixedArray* instances = FixedArray::cast(object);
 
   // Fill the referencing objects.
   count = DebugReferencedBy(target, instance_filter, max_references,
-                            instances, count,
-                            context_extension_function, arguments_function);
+                            instances, count, arguments_function);
 
   // Return result as JS array.
   Object* result =
       Heap::AllocateJSObject(
           Top::context()->global_context()->array_function());
   if (!result->IsFailure()) JSArray::cast(result)->SetContent(instances);
   return result;
 }
 
 
@@ skipping 237 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     Counters::gc_last_resort_from_js.Increment();
     Heap::CollectAllGarbage();
   }
 }
 
 
 } }  // namespace v8::internal