[heap] Clean up stale store buffer entries for aborted pages.

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 776 matching lines @@
   // True if parallel compaction is currently in progress.
   bool compaction_in_progress_;
 
   // Semaphore used to synchronize sweeper tasks.
   base::Semaphore pending_sweeper_tasks_semaphore_;
 
   // Semaphore used to synchronize compaction tasks.
   base::Semaphore pending_compaction_tasks_semaphore_;
 
   friend class Heap;
+  friend class StoreBuffer;

[Michael Lippautz, 2015/12/04 10:48:57]

This is needed because we otherwise would not be able to access
VisitLiveObjects() from within the store buffer.

Maybe we could at some point have something like a LiveObjectIterator(Page*)
that uses markbit information.

 };
 
 
 class MarkBitCellIterator BASE_EMBEDDED {
  public:
   explicit MarkBitCellIterator(MemoryChunk* chunk) : chunk_(chunk) {
     last_cell_index_ = Bitmap::IndexToCell(Bitmap::CellAlignIndex(
         chunk_->AddressToMarkbitIndex(chunk_->area_end())));
     cell_base_ = chunk_->area_start();
     cell_index_ = Bitmap::IndexToCell(
@@ skipping 43 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_MARK_COMPACT_H_