Add DependentCode to PropertyCells

src/mark-compact.cc

 // 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 2233 matching lines @@
         }
       }
     }
     {
       HeapObjectIterator js_global_property_cell_iterator(
           heap()->property_cell_space());
       HeapObject* cell;
       while ((cell = js_global_property_cell_iterator.Next()) != NULL) {
         ASSERT(cell->IsPropertyCell());
         if (IsMarked(cell)) {
-          int offset = PropertyCell::kValueOffset;
-          MarkCompactMarkingVisitor::VisitPointer(
-              heap(),
-              reinterpret_cast<Object**>(cell->address() + offset));
-          offset = PropertyCell::kTypeOffset;
-          MarkCompactMarkingVisitor::VisitPointer(
-              heap(),
-              reinterpret_cast<Object**>(cell->address() + offset));
+          MarkCompactMarkingVisitor::VisitPropertyCell(cell->map(), cell);
         }
       }
     }
   }
 
   RootMarkingVisitor root_visitor(heap());
   MarkRoots(&root_visitor);
 
   // The objects reachable from the roots are marked, yet unreachable
   // objects are unmarked.  Mark objects reachable due to host
@@ skipping 158 matching lines @@
       // This map is used for inobject slack tracking and has been detached
       // from SharedFunctionInfo during the mark phase.
       // Since it survived the GC, reattach it now.
       JSFunction::cast(map->constructor())->shared()->AttachInitialMap(map);
     }
 
     ClearNonLivePrototypeTransitions(map);
     ClearNonLiveMapTransitions(map, map_mark);
 
     if (map_mark.Get()) {
-      ClearNonLiveDependentCode(map);
+      ClearNonLiveDependentCode(map->dependent_code());
     } else {
       ClearAndDeoptimizeDependentCode(map);
     }
   }
+
+  // Iterate over property cell space, removing dependent code that is not
+  // otherwise kept alive by strong references.
+  HeapObjectIterator cell_iterator(heap_->property_cell_space());
+  for (HeapObject* cell = cell_iterator.Next();
+       cell != NULL;
+       cell = cell_iterator.Next()) {
+    ClearNonLiveDependentCode(PropertyCell::cast(cell)->dependent_code());

[Michael Starzinger, 2013/06/26 15:23:31]

This iteration should only concern itself with marked property cells, unmarked
cells should be safe to ignore.

[danno, 2013/06/26 15:42:40]

Done.

+  }
 }
 
 
 void MarkCompactCollector::ClearNonLivePrototypeTransitions(Map* map) {
   int number_of_transitions = map->NumberOfProtoTransitions();
   FixedArray* prototype_transitions = map->GetPrototypeTransitions();
 
   int new_number_of_transitions = 0;
   const int header = Map::kProtoTransitionHeaderSize;
   const int proto_offset = header + Map::kProtoTransitionPrototypeOffset;
@@ skipping 65 matching lines @@
     Code* code = entries->code_at(i);
     if (IsMarked(code) && !code->marked_for_deoptimization()) {
       code->set_marked_for_deoptimization(true);
     }
     entries->clear_at(i);
   }
   map->set_dependent_code(DependentCode::cast(heap()->empty_fixed_array()));
 }
 
 
-void MarkCompactCollector::ClearNonLiveDependentCode(Map* map) {
+void MarkCompactCollector::ClearNonLiveDependentCode(DependentCode* entries) {
   DisallowHeapAllocation no_allocation;
-  DependentCode* entries = map->dependent_code();
   DependentCode::GroupStartIndexes starts(entries);
   int number_of_entries = starts.number_of_entries();
   if (number_of_entries == 0) return;
   int new_number_of_entries = 0;
   // Go through all groups, remove dead codes and compact.
   for (int g = 0; g < DependentCode::kGroupCount; g++) {
     int group_number_of_entries = 0;
     for (int i = starts.at(g); i < starts.at(g + 1); i++) {
       Object* obj = entries->object_at(i);
       ASSERT(obj->IsCode() || IsMarked(obj));
@@ skipping 848 matching lines @@
   }
 
   GCTracer::Scope gc_scope(tracer_, GCTracer::Scope::MC_UPDATE_MISC_POINTERS);
 
   // Update pointers from cells.
   HeapObjectIterator cell_iterator(heap_->cell_space());
   for (HeapObject* cell = cell_iterator.Next();
        cell != NULL;
        cell = cell_iterator.Next()) {
     if (cell->IsCell()) {
-      Address value_address = reinterpret_cast<Address>(cell) +
-          (Cell::kValueOffset - kHeapObjectTag);
-      updating_visitor.VisitPointer(reinterpret_cast<Object**>(value_address));
+      Cell::BodyDescriptor::IterateBody(cell, &updating_visitor);
     }
   }
 
   HeapObjectIterator js_global_property_cell_iterator(
       heap_->property_cell_space());
   for (HeapObject* cell = js_global_property_cell_iterator.Next();
        cell != NULL;
        cell = js_global_property_cell_iterator.Next()) {
     if (cell->IsPropertyCell()) {
-      Address value_address =
-          reinterpret_cast<Address>(cell) +
-          (PropertyCell::kValueOffset - kHeapObjectTag);
-      updating_visitor.VisitPointer(reinterpret_cast<Object**>(value_address));
-      Address type_address =
-          reinterpret_cast<Address>(cell) +
-          (PropertyCell::kTypeOffset - kHeapObjectTag);
-      updating_visitor.VisitPointer(reinterpret_cast<Object**>(type_address));
+      PropertyCell::BodyDescriptor::IterateBody(cell, &updating_visitor);
     }
   }
 
   // Update pointer from the native contexts list.
   updating_visitor.VisitPointer(heap_->native_contexts_list_address());
 
   heap_->string_table()->Iterate(&updating_visitor);
 
   // Update pointers from external string table.
   heap_->UpdateReferencesInExternalStringTable(
@@ skipping 864 matching lines @@
   while (buffer != NULL) {
     SlotsBuffer* next_buffer = buffer->next();
     DeallocateBuffer(buffer);
     buffer = next_buffer;
   }
   *buffer_address = NULL;
 }
 
 
 } }  // namespace v8::internal