Allow partial scanning of large arrays in order to avoid

src/objects-visiting.h

 // Copyright 2012 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 195 matching lines @@
 class BodyVisitorBase : public AllStatic {
  public:
   INLINE(static void IteratePointers(Heap* heap,
                                      HeapObject* object,
                                      int start_offset,
                                      int end_offset)) {
     Object** start_slot = reinterpret_cast<Object**>(object->address() +
                                                      start_offset);
     Object** end_slot = reinterpret_cast<Object**>(object->address() +
                                                    end_offset);
-    StaticVisitor::VisitPointers(heap, start_slot, end_slot);
+    StaticVisitor::VisitPointers(heap, start_slot, start_slot, end_slot);
   }
 };
 
 
 template<typename StaticVisitor, typename BodyDescriptor, typename ReturnType>
 class FlexibleBodyVisitor : public BodyVisitorBase<StaticVisitor> {
  public:
   static inline ReturnType Visit(Map* map, HeapObject* object) {
     int object_size = BodyDescriptor::SizeOf(map, object);
     BodyVisitorBase<StaticVisitor>::IteratePointers(
@@ skipping 49 matching lines @@
 // inlining and specialization of StaticVisitor::VisitPointers methods).
 template<typename StaticVisitor>
 class StaticNewSpaceVisitor : public StaticVisitorBase {
  public:
   static void Initialize();
 
   static inline int IterateBody(Map* map, HeapObject* obj) {
     return table_.GetVisitor(map)(map, obj);
   }
 
-  static inline void VisitPointers(Heap* heap, Object** start, Object** end) {
+  static inline void VisitPointers(
+      Heap* heap, Object** anchor, Object** start, Object** end) {
     for (Object** p = start; p < end; p++) StaticVisitor::VisitPointer(heap, p);
   }
 
  private:
   static inline int VisitJSFunction(Map* map, HeapObject* object) {
     Heap* heap = map->GetHeap();
+    Object** start_slot =
+        HeapObject::RawField(object, JSFunction::kPropertiesOffset);
     VisitPointers(heap,
-                  HeapObject::RawField(object, JSFunction::kPropertiesOffset),
+                  start_slot,
+                  start_slot,
                   HeapObject::RawField(object, JSFunction::kCodeEntryOffset));
 
     // Don't visit code entry. We are using this visitor only during scavenges.
 
     VisitPointers(
         heap,
+        start_slot,
         HeapObject::RawField(object,
                              JSFunction::kCodeEntryOffset + kPointerSize),
         HeapObject::RawField(object,
                              JSFunction::kNonWeakFieldsEndOffset));
     return JSFunction::kSize;
   }
 
   static inline int VisitByteArray(Map* map, HeapObject* object) {
     return reinterpret_cast<ByteArray*>(object)->ByteArraySize();
   }
@@ skipping 121 matching lines @@
 
 
 template<typename StaticVisitor>
 VisitorDispatchTable<typename StaticMarkingVisitor<StaticVisitor>::Callback>
     StaticMarkingVisitor<StaticVisitor>::table_;
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_VISITING_H_