Revert of Replace slots buffer with remembered set.

src/heap/mark-compact.h

Index: src/heap/mark-compact.h
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index 20ac9f6c935873f164e2e062716757215ed68b41..cc5449f97765e7d1a6c2993b963ff569edc2df89 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -25,7 +25,9 @@
 class MarkCompactCollector;
 class MarkingVisitor;
 class RootMarkingVisitor;
-class LocalSlotsBuffer;
+class SlotsBuffer;
+class SlotsBufferAllocator;
+
 
 class Marking : public AllStatic {
  public:
@@ -393,8 +395,8 @@
         ->IsEvacuationCandidate();
   }
 
-  void RecordRelocSlot(Code* host, RelocInfo* rinfo, Object* target);
-  void RecordCodeEntrySlot(HeapObject* host, Address slot, Code* target);
+  void RecordRelocSlot(RelocInfo* rinfo, Object* target);
+  void RecordCodeEntrySlot(HeapObject* object, Address slot, Code* target);
   void RecordCodeTargetPatch(Address pc, Code* target);
   INLINE(void RecordSlot(HeapObject* object, Object** slot, Object* target));
   INLINE(void ForceRecordSlot(HeapObject* object, Object** slot,
@@ -405,8 +407,8 @@
 
   void MigrateObject(HeapObject* dst, HeapObject* src, int size,
                      AllocationSpace to_old_space,
-                     LocalSlotsBuffer* old_to_old_slots,
-                     LocalSlotsBuffer* old_to_new_slots);
+                     SlotsBuffer** evacuation_slots_buffer,
+                     LocalStoreBuffer* local_store_buffer);
 
   void InvalidateCode(Code* code);
 
@@ -482,8 +484,9 @@
   // whole transitive closure is known. They must be called before sweeping
   // when mark bits are still intact.
   bool IsSlotInBlackObject(Page* p, Address slot, HeapObject** out_object);
-  HeapObject* FindBlackObjectBySlotSlow(Address slot);
+  bool IsSlotInBlackObjectSlow(Page* p, Address slot);
   bool IsSlotInLiveObject(Address slot);
+  void VerifyIsSlotInLiveObject(Address slot, HeapObject* object);
 
   // Removes all the slots in the slot buffers that are within the given
   // address range.
@@ -517,7 +520,8 @@
   explicit MarkCompactCollector(Heap* heap);
 
   bool WillBeDeoptimized(Code* code);
-  void ClearInvalidRememberedSetSlots();
+  void EvictPopularEvacuationCandidate(Page* page);
+  void ClearInvalidStoreAndSlotsBufferEntries();
 
   void StartSweeperThreads();
 
@@ -545,6 +549,10 @@
   bool was_marked_incrementally_;
 
   bool evacuation_;
+
+  SlotsBufferAllocator* slots_buffer_allocator_;
+
+  SlotsBuffer* migration_slots_buffer_;
 
   // Finishes GC, performs heap verification if enabled.
   void Finish();
@@ -699,6 +707,9 @@
   void EvacuateNewSpacePrologue();
   void EvacuateNewSpaceEpilogue();
 
+  void AddEvacuationSlotsBufferSynchronized(
+      SlotsBuffer* evacuation_slots_buffer);
+
   void EvacuatePagesInParallel();
 
   // The number of parallel compaction tasks, including the main thread.
@@ -734,8 +745,16 @@
 
   // Updates store buffer and slot buffer for a pointer in a migrating object.
   void RecordMigratedSlot(Object* value, Address slot,
-                          LocalSlotsBuffer* old_to_old_slots,
-                          LocalSlotsBuffer* old_to_new_slots);
+                          SlotsBuffer** evacuation_slots_buffer,
+                          LocalStoreBuffer* local_store_buffer);
+
+  // Adds the code entry slot to the slots buffer.
+  void RecordMigratedCodeEntrySlot(Address code_entry, Address code_entry_slot,
+                                   SlotsBuffer** evacuation_slots_buffer);
+
+  // Adds the slot of a moved code object.
+  void RecordMigratedCodeObjectSlot(Address code_object,
+                                    SlotsBuffer** evacuation_slots_buffer);
 
 #ifdef DEBUG
   friend class MarkObjectVisitor;
@@ -754,6 +773,14 @@
 
   List<Page*> evacuation_candidates_;
   List<NewSpacePage*> newspace_evacuation_candidates_;
+
+  // The evacuation_slots_buffers_ are used by the compaction threads.
+  // When a compaction task finishes, it uses
+  // AddEvacuationSlotsbufferSynchronized to adds its slots buffer to the
+  // evacuation_slots_buffers_ list using the evacuation_slots_buffers_mutex_
+  // lock.
+  base::Mutex evacuation_slots_buffers_mutex_;
+  List<SlotsBuffer*> evacuation_slots_buffers_;
 
   base::SmartPointer<FreeList> free_list_old_space_;
   base::SmartPointer<FreeList> free_list_code_space_;