Generalize virtually dispatched scavenger to virtually dispatched specialized visitors.

src/heap.cc

 // Copyright 2009 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 19 matching lines @@
 #include "accessors.h"
 #include "api.h"
 #include "bootstrapper.h"
 #include "codegen-inl.h"
 #include "compilation-cache.h"
 #include "debug.h"
 #include "heap-profiler.h"
 #include "global-handles.h"
 #include "mark-compact.h"
 #include "natives.h"
+#include "objects-visiting.h"
 #include "scanner.h"
 #include "scopeinfo.h"
 #include "snapshot.h"
 #include "v8threads.h"
 #if V8_TARGET_ARCH_ARM && !V8_INTERPRETED_REGEXP
 #include "regexp-macro-assembler.h"
 #include "arm/regexp-macro-assembler-arm.h"
 #endif
 
 
@@ skipping 975 matching lines @@
       // String got promoted.  Move it to the old string list.
       ExternalStringTable::AddOldString(target);
     }
   }
 
   ASSERT(last <= end);
   ExternalStringTable::ShrinkNewStrings(static_cast<int>(last - start));
 }
 
 
+class NewSpaceScavenger : public StaticNewSpaceVisitor<NewSpaceScavenger> {
+ public:
+  static inline void VisitPointer(Object** p) {
+    Object* object = *p;
+    if (!Heap::InNewSpace(object)) return;
+    Heap::ScavengeObject(reinterpret_cast<HeapObject**>(p),
+                         reinterpret_cast<HeapObject*>(object));
+  }
+};
+
+
 Address Heap::DoScavenge(ObjectVisitor* scavenge_visitor,
                          Address new_space_front) {
   do {
     ASSERT(new_space_front <= new_space_.top());
 
     // The addresses new_space_front and new_space_.top() define a
     // queue of unprocessed copied objects.  Process them until the
     // queue is empty.
     while (new_space_front < new_space_.top()) {
       HeapObject* object = HeapObject::FromAddress(new_space_front);
-      Map* map = object->map();
-      int size = object->SizeFromMap(map);
-      object->IterateBody(map->instance_type(), size, scavenge_visitor);
-      new_space_front += size;
+      new_space_front += NewSpaceScavenger::IterateBody(object->map(), object);
     }
 
     // Promote and process all the to-be-promoted objects.
     while (!promotion_queue.is_empty()) {
       HeapObject* target;
       int size;
       promotion_queue.remove(&target, &size);
 
       // Promoted object might be already partially visited
       // during dirty regions iteration. Thus we search specificly
       // for pointers to from semispace instead of looking for pointers
       // to new space.
       ASSERT(!target->IsMap());
       IterateAndMarkPointersToFromSpace(target->address(),
                                         target->address() + size,
                                         &ScavengePointer);
     }
 
     // Take another spin if there are now unswept objects in new space
     // (there are currently no more unswept promoted objects).
   } while (new_space_front < new_space_.top());
 
   return new_space_front;
 }
 
 
+class ScavengingVisitor : public StaticVisitorBase {
+ public:
+  static void Initialize() {
+    table_.Register(kVisitSeqAsciiString, &EvacuateSeqAsciiString);
+    table_.Register(kVisitSeqTwoByteString, &EvacuateSeqTwoByteString);
+    table_.Register(kVisitShortcutCandidate, &EvacuateShortcutCandidate);
+    table_.Register(kVisitByteArray, &EvacuateByteArray);
+    table_.Register(kVisitFixedArray, &EvacuateFixedArray);
+
+    typedef ObjectEvacuationStrategy<POINTER_OBJECT> PointerObject;
+
+    table_.Register(kVisitConsString,
+                    &ObjectEvacuationStrategy<POINTER_OBJECT>::
+                        VisitSpecialized<ConsString::kSize>);
+
+    table_.Register(kVisitSharedFunctionInfo,
+                    &ObjectEvacuationStrategy<POINTER_OBJECT>::
+                        VisitSpecialized<SharedFunctionInfo::kSize>);
+
+    table_.RegisterSpecializations<ObjectEvacuationStrategy<DATA_OBJECT>,
+                                   kVisitDataObject,
+                                   kVisitDataObjectGeneric>();
+
+    table_.RegisterSpecializations<ObjectEvacuationStrategy<POINTER_OBJECT>,
+                                   kVisitJSObject,
+                                   kVisitJSObjectGeneric>();
+
+    table_.RegisterSpecializations<ObjectEvacuationStrategy<POINTER_OBJECT>,
+                                   kVisitStruct,
+                                   kVisitStructGeneric>();
+  }
+
+
+  static inline void Scavenge(Map* map, HeapObject** slot, HeapObject* obj) {
+    table_.GetVisitor(map)(map, slot, obj);
+  }
+
+
+ private:
+  enum ObjectContents  { DATA_OBJECT, POINTER_OBJECT };
+  enum SizeRestriction { SMALL, UNKNOWN_SIZE };
+
 #if defined(DEBUG) || defined(ENABLE_LOGGING_AND_PROFILING)
-static void RecordCopiedObject(HeapObject* obj) {
-  bool should_record = false;
+  static void RecordCopiedObject(HeapObject* obj) {
+    bool should_record = false;
 #ifdef DEBUG
-  should_record = FLAG_heap_stats;
+    should_record = FLAG_heap_stats;
 #endif
 #ifdef ENABLE_LOGGING_AND_PROFILING
-  should_record = should_record || FLAG_log_gc;
+    should_record = should_record || FLAG_log_gc;
 #endif
-  if (should_record) {
-    if (Heap::new_space()->Contains(obj)) {
-      Heap::new_space()->RecordAllocation(obj);
-    } else {
-      Heap::new_space()->RecordPromotion(obj);
-    }
-  }
-}
+    if (should_record) {
+      if (Heap::new_space()->Contains(obj)) {
+        Heap::new_space()->RecordAllocation(obj);
+      } else {
+        Heap::new_space()->RecordPromotion(obj);
+      }
+    }
+  }
 #endif  // defined(DEBUG) || defined(ENABLE_LOGGING_AND_PROFILING)
 
-
-// Helper function used by CopyObject to copy a source object to an
-// allocated target object and update the forwarding pointer in the source
-// object.  Returns the target object.
-inline static HeapObject* MigrateObject(HeapObject* source,
-                                        HeapObject* target,
-                                        int size) {
-  // Copy the content of source to target.
-  Heap::CopyBlock(target->address(), source->address(), size);
-
-  // Set the forwarding address.
-  source->set_map_word(MapWord::FromForwardingAddress(target));
+  // Helper function used by CopyObject to copy a source object to an
+  // allocated target object and update the forwarding pointer in the source
+  // object.  Returns the target object.
+  INLINE(static HeapObject* MigrateObject(HeapObject* source,
+                                          HeapObject* target,
+                                          int size)) {
+    // Copy the content of source to target.
+    Heap::CopyBlock(target->address(), source->address(), size);
+
+    // Set the forwarding address.
+    source->set_map_word(MapWord::FromForwardingAddress(target));
 
 #if defined(DEBUG) || defined(ENABLE_LOGGING_AND_PROFILING)
-  // Update NewSpace stats if necessary.
-  RecordCopiedObject(target);
+    // Update NewSpace stats if necessary.
+    RecordCopiedObject(target);
 #endif
-  HEAP_PROFILE(ObjectMoveEvent(source->address(), target->address()));
-
-  return target;
-}
-
-
-enum ObjectContents  { DATA_OBJECT, POINTER_OBJECT };
-enum SizeRestriction { SMALL, UNKNOWN_SIZE };
-
-
-template<ObjectContents object_contents, SizeRestriction size_restriction>
-static inline void EvacuateObject(Map* map,
-                                  HeapObject** slot,
-                                  HeapObject* object,
-                                  int object_size) {
-  ASSERT((size_restriction != SMALL) ||
-         (object_size <= Page::kMaxHeapObjectSize));
-  ASSERT(object->Size() == object_size);
-
-  if (Heap::ShouldBePromoted(object->address(), object_size)) {
-    Object* result;
-
-    if ((size_restriction != SMALL) &&
-        (object_size > Page::kMaxHeapObjectSize)) {
-      result = Heap::lo_space()->AllocateRawFixedArray(object_size);
-    } else {
-      if (object_contents == DATA_OBJECT) {
-        result = Heap::old_data_space()->AllocateRaw(object_size);
+    HEAP_PROFILE(ObjectMoveEvent(source->address(), target->address()));
+
+    return target;
+  }
+
+
+  template<ObjectContents object_contents, SizeRestriction size_restriction>
+  static inline void EvacuateObject(Map* map,
+                                    HeapObject** slot,
+                                    HeapObject* object,
+                                    int object_size) {
+    ASSERT((size_restriction != SMALL) ||
+           (object_size <= Page::kMaxHeapObjectSize));
+    ASSERT(object->Size() == object_size);
+
+    if (Heap::ShouldBePromoted(object->address(), object_size)) {
+      Object* result;
+
+      if ((size_restriction != SMALL) &&
+          (object_size > Page::kMaxHeapObjectSize)) {
+        result = Heap::lo_space()->AllocateRawFixedArray(object_size);
       } else {
-        result = Heap::old_pointer_space()->AllocateRaw(object_size);
-      }
-    }
-
-    if (!result->IsFailure()) {
-      HeapObject* target = HeapObject::cast(result);
-      *slot = MigrateObject(object, target, object_size);
-
-      if (object_contents == POINTER_OBJECT) {
-        promotion_queue.insert(target, object_size);
-      }
-
-      Heap::tracer()->increment_promoted_objects_size(object_size);
-      return;
-    }
-  }
-  Object* result = Heap::new_space()->AllocateRaw(object_size);
-  ASSERT(!result->IsFailure());
-  *slot = MigrateObject(object, HeapObject::cast(result), object_size);
-  return;
-}
-
-
-template<int object_size_in_words, ObjectContents object_contents>
-static inline void EvacuateObjectOfFixedSize(Map* map,
-                                             HeapObject** slot,
-                                             HeapObject* object) {
-  const int object_size = object_size_in_words << kPointerSizeLog2;
-  EvacuateObject<object_contents, SMALL>(map, slot, object, object_size);
-}
-
-
-template<ObjectContents object_contents>
-static inline void EvacuateObjectOfFixedSize(Map* map,
-                                             HeapObject** slot,
-                                             HeapObject* object) {
-  int object_size = map->instance_size();
-  EvacuateObject<object_contents, SMALL>(map, slot, object, object_size);
-}
-
-
-static inline void EvacuateFixedArray(Map* map,
-                                      HeapObject** slot,
-                                      HeapObject* object) {
-  int object_size = FixedArray::cast(object)->FixedArraySize();
-  EvacuateObject<POINTER_OBJECT, UNKNOWN_SIZE>(map, slot, object, object_size);
-}
-
-
-static inline void EvacuateByteArray(Map* map,
-                                     HeapObject** slot,
-                                     HeapObject* object) {
-  int object_size = ByteArray::cast(object)->ByteArraySize();
-  EvacuateObject<DATA_OBJECT, UNKNOWN_SIZE>(map, slot, object, object_size);
-}
-
-
-static Scavenger GetScavengerForSize(int object_size,
-                                     ObjectContents object_contents) {
-  ASSERT(IsAligned(object_size, kPointerSize));
-  ASSERT(object_size < Page::kMaxHeapObjectSize);
-
-  switch (object_size >> kPointerSizeLog2) {
-#define CASE(n)                                           \
-    case n:                                               \
-      if (object_contents == DATA_OBJECT) {               \
-        return static_cast<Scavenger>(                    \
-          &EvacuateObjectOfFixedSize<n, DATA_OBJECT>);    \
-      } else {                                            \
-        return static_cast<Scavenger>(                    \
-          &EvacuateObjectOfFixedSize<n, POINTER_OBJECT>); \
-      }
-
-    CASE(1);
-    CASE(2);
-    CASE(3);
-    CASE(4);
-    CASE(5);
-    CASE(6);
-    CASE(7);
-    CASE(8);
-    CASE(9);
-    CASE(10);
-    CASE(11);
-    CASE(12);
-    CASE(13);
-    CASE(14);
-    CASE(15);
-    CASE(16);
-    default:
-      if (object_contents == DATA_OBJECT) {
-        return static_cast<Scavenger>(&EvacuateObjectOfFixedSize<DATA_OBJECT>);
-      } else {
-        return static_cast<Scavenger>(
-            &EvacuateObjectOfFixedSize<POINTER_OBJECT>);
-      }
-
-#undef CASE
-  }
-}
-
-
-static inline void EvacuateSeqAsciiString(Map* map,
-                                          HeapObject** slot,
-                                          HeapObject* object) {
-  int object_size = SeqAsciiString::cast(object)->
-      SeqAsciiStringSize(map->instance_type());
-  EvacuateObject<DATA_OBJECT, UNKNOWN_SIZE>(map, slot, object, object_size);
-}
-
-
-static inline void EvacuateSeqTwoByteString(Map* map,
+        if (object_contents == DATA_OBJECT) {
+          result = Heap::old_data_space()->AllocateRaw(object_size);
+        } else {
+          result = Heap::old_pointer_space()->AllocateRaw(object_size);
+        }
+      }
+
+      if (!result->IsFailure()) {
+        HeapObject* target = HeapObject::cast(result);
+        *slot = MigrateObject(object, target, object_size);
+
+        if (object_contents == POINTER_OBJECT) {
+          promotion_queue.insert(target, object_size);
+        }
+
+        Heap::tracer()->increment_promoted_objects_size(object_size);
+        return;
+      }
+    }
+    Object* result = Heap::new_space()->AllocateRaw(object_size);
+    ASSERT(!result->IsFailure());
+    *slot = MigrateObject(object, HeapObject::cast(result), object_size);
+    return;
+  }
+
+
+  static inline void EvacuateFixedArray(Map* map,
+                                        HeapObject** slot,
+                                        HeapObject* object) {
+    int object_size = FixedArray::BodyDescriptor::SizeOf(map, object);
+    EvacuateObject<POINTER_OBJECT, UNKNOWN_SIZE>(map,
+                                                 slot,
+                                                 object,
+                                                 object_size);
+  }
+
+
+  static inline void EvacuateByteArray(Map* map,
+                                       HeapObject** slot,
+                                       HeapObject* object) {
+    int object_size = reinterpret_cast<ByteArray*>(object)->ByteArraySize();
+    EvacuateObject<DATA_OBJECT, UNKNOWN_SIZE>(map, slot, object, object_size);
+  }
+
+
+  static inline void EvacuateSeqAsciiString(Map* map,
                                             HeapObject** slot,
                                             HeapObject* object) {
-  int object_size = SeqTwoByteString::cast(object)->
-      SeqTwoByteStringSize(map->instance_type());
-  EvacuateObject<DATA_OBJECT, UNKNOWN_SIZE>(map, slot, object, object_size);
-}
-
-
-static inline bool IsShortcutCandidate(int type) {
-  return ((type & kShortcutTypeMask) == kShortcutTypeTag);
-}
-
-
-static inline void EvacuateShortcutCandidate(Map* map,
-                                             HeapObject** slot,
-                                             HeapObject* object) {
-  ASSERT(IsShortcutCandidate(map->instance_type()));
-
-  if (ConsString::cast(object)->unchecked_second() == Heap::empty_string()) {
-    HeapObject* first =
-        HeapObject::cast(ConsString::cast(object)->unchecked_first());
-
-    *slot = first;
-
-    if (!Heap::InNewSpace(first)) {
-      object->set_map_word(MapWord::FromForwardingAddress(first));
+    int object_size = SeqAsciiString::cast(object)->
+        SeqAsciiStringSize(map->instance_type());
+    EvacuateObject<DATA_OBJECT, UNKNOWN_SIZE>(map, slot, object, object_size);
+  }
+
+
+  static inline void EvacuateSeqTwoByteString(Map* map,
+                                              HeapObject** slot,
+                                              HeapObject* object) {
+    int object_size = SeqTwoByteString::cast(object)->
+        SeqTwoByteStringSize(map->instance_type());
+    EvacuateObject<DATA_OBJECT, UNKNOWN_SIZE>(map, slot, object, object_size);
+  }
+
+
+  static inline bool IsShortcutCandidate(int type) {
+    return ((type & kShortcutTypeMask) == kShortcutTypeTag);
+  }
+
+  static inline void EvacuateShortcutCandidate(Map* map,
+                                               HeapObject** slot,
+                                               HeapObject* object) {
+    ASSERT(IsShortcutCandidate(map->instance_type()));
+
+    if (ConsString::cast(object)->unchecked_second() == Heap::empty_string()) {
+      HeapObject* first =
+          HeapObject::cast(ConsString::cast(object)->unchecked_first());
+
+      *slot = first;
+
+      if (!Heap::InNewSpace(first)) {
+        object->set_map_word(MapWord::FromForwardingAddress(first));
+        return;
+      }
+
+      MapWord first_word = first->map_word();
+      if (first_word.IsForwardingAddress()) {
+        HeapObject* target = first_word.ToForwardingAddress();
+
+        *slot = target;
+        object->set_map_word(MapWord::FromForwardingAddress(target));
+        return;
+      }
+
+      Scavenge(first->map(), slot, first);
+      object->set_map_word(MapWord::FromForwardingAddress(*slot));
       return;
     }
 
-    MapWord first_word = first->map_word();
-    if (first_word.IsForwardingAddress()) {
-      HeapObject* target = first_word.ToForwardingAddress();
-
-      *slot = target;
-      object->set_map_word(MapWord::FromForwardingAddress(target));
-      return;
-    }
-
-    first->map()->Scavenge(slot, first);
-    object->set_map_word(MapWord::FromForwardingAddress(*slot));
-    return;
-  }
-
-  int object_size = ConsString::kSize;
-  EvacuateObject<POINTER_OBJECT, SMALL>(map, slot, object, object_size);
-}
-
-
-Scavenger Heap::GetScavenger(int instance_type, int instance_size) {
-  if (instance_type < FIRST_NONSTRING_TYPE) {
-    switch (instance_type & kStringRepresentationMask) {
-      case kSeqStringTag:
-        if ((instance_type & kStringEncodingMask) == kAsciiStringTag) {
-          return &EvacuateSeqAsciiString;
-        } else {
-          return &EvacuateSeqTwoByteString;
-        }
-
-      case kConsStringTag:
-        if (IsShortcutCandidate(instance_type)) {
-          return &EvacuateShortcutCandidate;
-        } else {
-          ASSERT(instance_size == ConsString::kSize);
-          return GetScavengerForSize(ConsString::kSize, POINTER_OBJECT);
-        }
-
-      case kExternalStringTag:
-        ASSERT(instance_size == ExternalString::kSize);
-        return GetScavengerForSize(ExternalString::kSize, DATA_OBJECT);
-    }
-    UNREACHABLE();
-  }
-
-  switch (instance_type) {
-    case BYTE_ARRAY_TYPE:
-      return reinterpret_cast<Scavenger>(&EvacuateByteArray);
-
-    case FIXED_ARRAY_TYPE:
-      return reinterpret_cast<Scavenger>(&EvacuateFixedArray);
-
-    case JS_OBJECT_TYPE:
-    case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
-    case JS_VALUE_TYPE:
-    case JS_ARRAY_TYPE:
-    case JS_REGEXP_TYPE:
-    case JS_FUNCTION_TYPE:
-    case JS_GLOBAL_PROXY_TYPE:
-    case JS_GLOBAL_OBJECT_TYPE:
-    case JS_BUILTINS_OBJECT_TYPE:
-      return GetScavengerForSize(instance_size, POINTER_OBJECT);
-
-    case ODDBALL_TYPE:
-      return NULL;
-
-    case PROXY_TYPE:
-      return GetScavengerForSize(Proxy::kSize, DATA_OBJECT);
-
-    case MAP_TYPE:
-      return NULL;
-
-    case CODE_TYPE:
-      return NULL;
-
-    case JS_GLOBAL_PROPERTY_CELL_TYPE:
-      return NULL;
-
-    case HEAP_NUMBER_TYPE:
-    case FILLER_TYPE:
-    case PIXEL_ARRAY_TYPE:
-    case EXTERNAL_BYTE_ARRAY_TYPE:
-    case EXTERNAL_UNSIGNED_BYTE_ARRAY_TYPE:
-    case EXTERNAL_SHORT_ARRAY_TYPE:
-    case EXTERNAL_UNSIGNED_SHORT_ARRAY_TYPE:
-    case EXTERNAL_INT_ARRAY_TYPE:
-    case EXTERNAL_UNSIGNED_INT_ARRAY_TYPE:
-    case EXTERNAL_FLOAT_ARRAY_TYPE:
-      return GetScavengerForSize(instance_size, DATA_OBJECT);
-
-    case SHARED_FUNCTION_INFO_TYPE:
-      return GetScavengerForSize(SharedFunctionInfo::kAlignedSize,
-                                 POINTER_OBJECT);
-
-#define MAKE_STRUCT_CASE(NAME, Name, name) \
-        case NAME##_TYPE:
-      STRUCT_LIST(MAKE_STRUCT_CASE)
-#undef MAKE_STRUCT_CASE
-          return GetScavengerForSize(instance_size, POINTER_OBJECT);
-    default:
-      UNREACHABLE();
-      return NULL;
-  }
-}
+    int object_size = ConsString::kSize;
+    EvacuateObject<POINTER_OBJECT, SMALL>(map, slot, object, object_size);
+  }
+
+  template<ObjectContents object_contents>
+  class ObjectEvacuationStrategy {
+   public:
+    template<int object_size>
+    static inline void VisitSpecialized(Map* map,
+                                        HeapObject** slot,
+                                        HeapObject* object) {
+      EvacuateObject<object_contents, SMALL>(map, slot, object, object_size);
+    }
+
+    static inline void Visit(Map* map,
+                             HeapObject** slot,
+                             HeapObject* object) {
+      int object_size = map->instance_size();
+      EvacuateObject<object_contents, SMALL>(map, slot, object, object_size);
+    }
+  };
+
+  typedef void (*Callback)(Map* map, HeapObject** slot, HeapObject* object);
+
+  static VisitorDispatchTable<Callback> table_;
+};
+
+
+VisitorDispatchTable<ScavengingVisitor::Callback> ScavengingVisitor::table_;
 
 
 void Heap::ScavengeObjectSlow(HeapObject** p, HeapObject* object) {
   ASSERT(InFromSpace(object));
   MapWord first_word = object->map_word();
   ASSERT(!first_word.IsForwardingAddress());
   Map* map = first_word.ToMap();
-  map->Scavenge(p, object);
+  ScavengingVisitor::Scavenge(map, p, object);
 }
 
 
 void Heap::ScavengePointer(HeapObject** p) {
   ScavengeObject(p, *p);
 }
 
 
 Object* Heap::AllocatePartialMap(InstanceType instance_type,
                                  int instance_size) {
   Object* result = AllocateRawMap();
   if (result->IsFailure()) return result;
 
   // Map::cast cannot be used due to uninitialized map field.
   reinterpret_cast<Map*>(result)->set_map(raw_unchecked_meta_map());
   reinterpret_cast<Map*>(result)->set_instance_type(instance_type);
   reinterpret_cast<Map*>(result)->set_instance_size(instance_size);
   reinterpret_cast<Map*>(result)->
-      set_scavenger(GetScavenger(instance_type, instance_size));
+      set_visitor_id(
+          StaticVisitorBase::GetVisitorId(instance_type, instance_size));
   reinterpret_cast<Map*>(result)->set_inobject_properties(0);
   reinterpret_cast<Map*>(result)->set_pre_allocated_property_fields(0);
   reinterpret_cast<Map*>(result)->set_unused_property_fields(0);
   reinterpret_cast<Map*>(result)->set_bit_field(0);
   reinterpret_cast<Map*>(result)->set_bit_field2(0);
   return result;
 }
 
 
 Object* Heap::AllocateMap(InstanceType instance_type, int instance_size) {
   Object* result = AllocateRawMap();
   if (result->IsFailure()) return result;
 
   Map* map = reinterpret_cast<Map*>(result);
   map->set_map(meta_map());
   map->set_instance_type(instance_type);
-  map->set_scavenger(GetScavenger(instance_type, instance_size));
+  map->set_visitor_id(
+      StaticVisitorBase::GetVisitorId(instance_type, instance_size));
   map->set_prototype(null_value());
   map->set_constructor(null_value());
   map->set_instance_size(instance_size);
   map->set_inobject_properties(0);
   map->set_pre_allocated_property_fields(0);
   map->set_instance_descriptors(empty_descriptor_array());
   map->set_code_cache(empty_fixed_array());
   map->set_unused_property_fields(0);
   map->set_bit_field(0);
   map->set_bit_field2((1 << Map::kIsExtensible) | (1 << Map::kHasFastElements));
@@ skipping 2729 matching lines @@
   // call Heap::TearDown() to release allocated memory.
   //
   // If the heap is not yet configured (eg, through the API), configure it.
   // Configuration is based on the flags new-space-size (really the semispace
   // size) and old-space-size if set or the initial values of semispace_size_
   // and old_generation_size_ otherwise.
   if (!heap_configured) {
     if (!ConfigureHeapDefault()) return false;
   }
 
+  ScavengingVisitor::Initialize();
+  NewSpaceScavenger::Initialize();
+  MarkCompactCollector::Initialize();
+
   // Setup memory allocator and reserve a chunk of memory for new
   // space.  The chunk is double the size of the requested reserved
   // new space size to ensure that we can find a pair of semispaces that
   // are contiguous and aligned to their size.
   if (!MemoryAllocator::Setup(MaxReserved())) return false;
   void* chunk =
       MemoryAllocator::ReserveInitialChunk(4 * reserved_semispace_size_);
   if (chunk == NULL) return false;
 
   // Align the pair of semispaces to their size, which must be a power
@@ skipping 664 matching lines @@
         PrintF(MarkCompactCollector::HasCompacted() ? "mc" : "ms");
         break;
       default:
         UNREACHABLE();
     }
     PrintF(" ");
 
     PrintF("external=%d ", static_cast<int>(scopes_[Scope::EXTERNAL]));
     PrintF("mark=%d ", static_cast<int>(scopes_[Scope::MC_MARK]));
     PrintF("sweep=%d ", static_cast<int>(scopes_[Scope::MC_SWEEP]));
+    PrintF("sweepns=%d ", static_cast<int>(scopes_[Scope::MC_SWEEP_NEWSPACE]));
     PrintF("compact=%d ", static_cast<int>(scopes_[Scope::MC_COMPACT]));
     PrintF("flushcode=%d ", static_cast<int>(scopes_[Scope::MC_FLUSH_CODE]));
 
     PrintF("total_size_before=%d ", start_size_);
     PrintF("total_size_after=%d ", Heap::SizeOfObjects());
     PrintF("holes_size_before=%d ", in_free_list_or_wasted_before_gc_);
     PrintF("holes_size_after=%d ", CountTotalHolesSize());
 
     PrintF("allocated=%d ", allocated_since_last_gc_);
     PrintF("promoted=%d ", promoted_objects_size_);
@@ skipping 131 matching lines @@
 void ExternalStringTable::TearDown() {
   new_space_strings_.Free();
   old_space_strings_.Free();
 }
 
 
 List<Object*> ExternalStringTable::new_space_strings_;
 List<Object*> ExternalStringTable::old_space_strings_;
 
 } }  // namespace v8::internal