Directly remove slot buffer entries in deoptimized code objects.

src/heap/mark-compact.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_MARK_COMPACT_H_
 #define V8_HEAP_MARK_COMPACT_H_
 
 #include "src/base/bits.h"
 #include "src/heap/spaces.h"
 
@@ skipping 98 matching lines @@
 
   INLINE(static void BlackToGrey(HeapObject* obj)) {
     BlackToGrey(MarkBitFrom(obj));
   }
 
   INLINE(static void AnyToGrey(MarkBit markbit)) {
     markbit.Set();
     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
   enum ObjectColor {
     BLACK_OBJECT,
     WHITE_OBJECT,
     GREY_OBJECT,
     IMPOSSIBLE_COLOR
   };
 
@@ skipping 223 matching lines @@
       case JS_RETURN_SLOT:
         return "JS_RETURN_SLOT";
       case NUMBER_OF_SLOT_TYPES:
         return "NUMBER_OF_SLOT_TYPES";
     }
     return "UNKNOWN SlotType";
   }
 
   void UpdateSlots(Heap* heap);
 
-  void UpdateSlotsWithFilter(Heap* heap);
-
   SlotsBuffer* next() { return next_; }
 
   static int SizeOfChain(SlotsBuffer* buffer) {
     if (buffer == NULL) return 0;
     return static_cast<int>(buffer->idx_ +
                             (buffer->chain_length_ - 1) * kNumberOfElements);
   }
 
   inline bool IsFull() { return idx_ == kNumberOfElements; }
 
   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();
     }
   }
 
   enum AdditionMode { FAIL_ON_OVERFLOW, IGNORE_OVERFLOW };
 
   static bool ChainLengthThresholdReached(SlotsBuffer* buffer) {
     return buffer != NULL && buffer->chain_length_ >= kChainLengthThreshold;
   }
 
@@ skipping 18 matching lines @@
   static bool AddTo(SlotsBufferAllocator* allocator,
                     SlotsBuffer** buffer_address, SlotType type, Address addr,
                     AdditionMode mode);
 
   // Eliminates all stale entries from the slots buffer, i.e., slots that
   // are not part of live objects anymore. This method must be called after
   // marking, when the whole transitive closure is known and must be called
   // 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);
 
   static const int kNumberOfElements = 1021;
 
  private:
   static const int kChainLengthThreshold = 15;
 
   intptr_t idx_;
   intptr_t chain_length_;
@@ skipping 227 matching lines @@
 
   void MigrateObject(HeapObject* dst, HeapObject* src, int size,
                      AllocationSpace to_old_space);
 
   void MigrateObjectTagged(HeapObject* dst, HeapObject* src, int size);
   void MigrateObjectMixed(HeapObject* dst, HeapObject* src, int size);
   void MigrateObjectRaw(HeapObject* dst, HeapObject* src, int size);
 
   bool TryPromoteObject(HeapObject* object, int object_size);
 
-  void InvalidateCode(Code* code);
-
   void ClearMarkbits();
 
   bool abort_incremental_marking() const { return abort_incremental_marking_; }
 
   bool finalize_incremental_marking() const {
     return finalize_incremental_marking_;
   }
 
   bool is_compacting() const { return compacting_; }
 
@@ skipping 51 matching lines @@
 
   void InitializeMarkingDeque();
 
   // The following four methods can just be called after marking, when the
   // 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);
   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;
 
   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();
 
   void StartSweeperThreads();
 
 #ifdef DEBUG
   enum CollectorState {
     IDLE,
     PREPARE_GC,
@@ skipping 196 matching lines @@
 #endif
 
   Heap* heap_;
   base::VirtualMemory* marking_deque_memory_;
   size_t marking_deque_memory_committed_;
   MarkingDeque marking_deque_;
   CodeFlusher* code_flusher_;
   bool have_code_to_deoptimize_;
 
   List<Page*> evacuation_candidates_;
-  List<Code*> invalidated_code_;
 
   SmartPointer<FreeList> free_list_old_space_;
 
   friend class Heap;
 };
 
 
 class MarkBitCellIterator BASE_EMBEDDED {
  public:
   explicit MarkBitCellIterator(MemoryChunk* chunk) : chunk_(chunk) {
@@ skipping 47 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_MARK_COMPACT_H_