Directly remove slot buffer entries in deoptimized code objects.

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 de21aa1d901780a64f87ec1344de39d6c8653148..bd478d7c06cb999e31e0e1f0b0ca73a10679416f 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -116,10 +116,6 @@ class Marking {
     markbit.Next().Set();
   }
 
-  static void SetAllMarkBitsInRange(MarkBit start, MarkBit end);
-  static void ClearAllMarkBitsOfCellsContainedInRange(MarkBit start,
-                                                      MarkBit end);
-
   void TransferMark(Address old_start, Address new_start);
 
 #ifdef DEBUG
@@ -363,8 +359,6 @@ class SlotsBuffer {
 
   void UpdateSlots(Heap* heap);
 
-  void UpdateSlotsWithFilter(Heap* heap);
-
   SlotsBuffer* next() { return next_; }
 
   static int SizeOfChain(SlotsBuffer* buffer) {
@@ -377,14 +371,9 @@ class SlotsBuffer {
 
   inline bool HasSpaceForTypedSlot() { return idx_ < kNumberOfElements - 1; }
 
-  static void UpdateSlotsRecordedIn(Heap* heap, SlotsBuffer* buffer,
-                                    bool code_slots_filtering_required) {
+  static void UpdateSlotsRecordedIn(Heap* heap, SlotsBuffer* buffer) {
     while (buffer != NULL) {
-      if (code_slots_filtering_required) {
-        buffer->UpdateSlotsWithFilter(heap);
-      } else {
-        buffer->UpdateSlots(heap);
-      }
+      buffer->UpdateSlots(heap);
       buffer = buffer->next();
     }
   }
@@ -423,6 +412,10 @@ class SlotsBuffer {
   // before sweeping when mark bits are still intact.
   static void RemoveInvalidSlots(Heap* heap, SlotsBuffer* buffer);
 
+  // Eliminate all slots that point to the given invalid_object.
+  static void RemoveObjectSlots(Heap* heap, SlotsBuffer* buffer,
+                                HeapObject* invalid_object);
+
   // Ensures that there are no invalid slots in the chain of slots buffers.
   static void VerifySlots(Heap* heap, SlotsBuffer* buffer);
 
@@ -670,8 +663,6 @@ class MarkCompactCollector {
 
   bool TryPromoteObject(HeapObject* object, int object_size);
 
-  void InvalidateCode(Code* code);
-
   void ClearMarkbits();
 
   bool abort_incremental_marking() const { return abort_incremental_marking_; }
@@ -743,6 +734,7 @@ class MarkCompactCollector {
   bool IsSlotInBlackObjectSlow(Page* p, Address slot);
   bool IsSlotInLiveObject(Address slot);
   void VerifyIsSlotInLiveObject(Address slot, HeapObject* object);
+  void RemoveObjectSlots(HeapObject* invalid_object);

[Michael Starzinger, 2015/06/30 08:54:19]

nit: The comment above this block doesn't really apply to this method, correct?
Can we add an empty newline to indicate that?

[Hannes Payer (out of office), 2015/06/30 09:02:10]

Done.

 
  private:
   class SweeperTask;
@@ -750,10 +742,7 @@ class MarkCompactCollector {
   explicit MarkCompactCollector(Heap* heap);
   ~MarkCompactCollector();
 
-  bool MarkInvalidatedCode();
   bool WillBeDeoptimized(Code* code);
-  void RemoveDeadInvalidatedCode();
-  void ProcessInvalidatedCode(ObjectVisitor* visitor);
   void EvictPopularEvacuationCandidate(Page* page);
   void ClearInvalidSlotsBufferEntries(PagedSpace* space);
   void ClearInvalidStoreAndSlotsBufferEntries();
@@ -970,7 +959,6 @@ class MarkCompactCollector {
   bool have_code_to_deoptimize_;
 
   List<Page*> evacuation_candidates_;
-  List<Code*> invalidated_code_;
 
   SmartPointer<FreeList> free_list_old_space_;