Allow partial scanning of large arrays in order to avoid

src/objects-visiting-inl.h

Index: src/objects-visiting-inl.h
===================================================================
--- src/objects-visiting-inl.h	(revision 12609)
+++ src/objects-visiting-inl.h	(working copy)
@@ -262,9 +262,11 @@
       map_object->instance_type() >= FIRST_JS_RECEIVER_TYPE) {
     MarkMapContents(heap, map_object);
   } else {
-    StaticVisitor::VisitPointers(heap,
-        HeapObject::RawField(object, Map::kPointerFieldsBeginOffset),
-        HeapObject::RawField(object, Map::kPointerFieldsEndOffset));
+    Object** start_slot =
+        HeapObject::RawField(object, Map::kPointerFieldsBeginOffset);
+    Object** end_slot =
+        HeapObject::RawField(object, Map::kPointerFieldsEndOffset);
+    StaticVisitor::VisitPointers(heap, start_slot, start_slot, end_slot);
   }
 }
 
@@ -286,9 +288,12 @@
     Map* map, HeapObject* object) {
   int last_property_offset =
       JSRegExp::kSize + kPointerSize * map->inobject_properties();
-  StaticVisitor::VisitPointers(map->GetHeap(),
-      HeapObject::RawField(object, JSRegExp::kPropertiesOffset),
-      HeapObject::RawField(object, last_property_offset));
+  Object** start_slot =
+      HeapObject::RawField(object, JSRegExp::kPropertiesOffset);
+  Object** end_slot =
+      HeapObject::RawField(object, last_property_offset);
+  StaticVisitor::VisitPointers(
+      map->GetHeap(), start_slot, start_slot, end_slot);
 }
 
 
@@ -315,9 +320,11 @@
   // Mark the pointer fields of the Map. Since the transitions array has
   // been marked already, it is fine that one of these fields contains a
   // pointer to it.
-  StaticVisitor::VisitPointers(heap,
-      HeapObject::RawField(map, Map::kPointerFieldsBeginOffset),
-      HeapObject::RawField(map, Map::kPointerFieldsEndOffset));
+  Object** start_slot =
+      HeapObject::RawField(map, Map::kPointerFieldsBeginOffset);
+  Object** end_slot =
+      HeapObject::RawField(map, Map::kPointerFieldsEndOffset);
+  StaticVisitor::VisitPointers(heap, start_slot, start_slot, end_slot);
 }