[heap] Evacuation for young generation

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 <deque>
 
 #include "src/base/bits.h"
@@ skipping 404 matching lines @@
   template <class Visitor>
   bool VisitBlackObjects(MemoryChunk* chunk, const MarkingState& state,
                          Visitor* visitor, IterationMode iteration_mode);
 
  private:
   void RecomputeLiveBytes(MemoryChunk* chunk, const MarkingState& state);
 };
 
 enum PageEvacuationMode { NEW_TO_NEW, NEW_TO_OLD };
 
 class MinorMarkCompactCollector {

[Hannes Payer (out of office), 2017/04/21 14:35:18]

Would it make sense to have a higher level abstract MarkCompact collector class
from  from which the two instances inherit and implement the interface?

[Michael Lippautz, 2017/04/24 13:15:08]

Yes, I started implementing that in a smaller CL on the side.

  public:
+  MarkingState marking_state(HeapObject* object) const {
+    return MarkingState::External(object);
+  }
+
+  MarkingState marking_state(MemoryChunk* chunk) const {
+    return MarkingState::External(chunk);
+  }
+
   explicit MinorMarkCompactCollector(Heap* heap)
-      : heap_(heap), marking_deque_(heap) {}
+      : heap_(heap), marking_deque_(heap), page_parallel_job_semaphore_(0) {}
 
   void SetUp();
   void TearDown();
 
   void CollectGarbage();
 
   inline Heap* heap() const { return heap_; }
 
  private:
   class RootMarkingVisitor;
 
   inline Isolate* isolate() { return heap()->isolate(); }
   inline MarkingDeque* marking_deque() { return &marking_deque_; }
 
   V8_INLINE void MarkObject(HeapObject* obj);
   V8_INLINE void PushBlack(HeapObject* obj);
 
   SlotCallbackResult CheckAndMarkObject(Heap* heap, Address slot_address);
   void MarkLiveObjects();
   void ProcessMarkingDeque();
   void EmptyMarkingDeque();
+  void ClearNonLiveReferences();
+
+  void EvacuatePrologue();
+  void EvacuateEpilogue();
+  void EvacuateNewSpace(std::vector<HeapObject*>* black_allocation_objects);
+  void EvacuatePagesInParallel(
+      std::vector<HeapObject*>* black_allocation_objects);
+  void UpdatePointersAfterEvacuation();
 
   Heap* heap_;
   MarkingDeque marking_deque_;
+  base::Semaphore page_parallel_job_semaphore_;
+  List<Page*> new_space_evacuation_pages_;
 
   friend class StaticYoungGenerationMarkingVisitor;
 };
 
 // -------------------------------------------------------------------------
 // Mark-Compact collector
 class MarkCompactCollector {
  public:
   class RootMarkingVisitor;
 
@@ skipping 71 matching lines @@
     // Counter is actively maintained by the concurrent tasks to avoid querying
     // the semaphore for maintaining a task counter on the main thread.
     base::AtomicNumber<intptr_t> num_sweeping_tasks_;
   };
 
   enum IterationMode {
     kKeepMarking,
     kClearMarkbits,
   };
 
+  MarkingState marking_state(HeapObject* object) const {
+    return MarkingState::Internal(object);
+  }
+
+  MarkingState marking_state(MemoryChunk* chunk) const {
+    return MarkingState::Internal(chunk);
+  }
+
   static void Initialize();
 
   static SlotCallbackResult CheckAndMarkObject(Heap* heap,
                                                Address slot_address);
 
   void SetUp();
 
   void TearDown();
 
   void CollectEvacuationCandidates(PagedSpace* space);
@@ skipping 232 matching lines @@
 
   // Starts sweeping of spaces by contributing on the main thread and setting
   // up other pages for sweeping. Does not start sweeper tasks.
   void StartSweepSpaces();
   void StartSweepSpace(PagedSpace* space);
 
   void EvacuatePrologue();
   void EvacuateEpilogue();
   void EvacuatePagesInParallel();
 
-  // The number of parallel compaction tasks, including the main thread.
-  int NumberOfParallelCompactionTasks(int pages, intptr_t live_bytes);
-
   void EvacuateNewSpaceAndCandidates();
 
   void UpdatePointersAfterEvacuation();
 
   void ReleaseEvacuationCandidates();
 
 
 #ifdef DEBUG
   friend class MarkObjectVisitor;
   static void VisitObject(HeapObject* obj);
@@ skipping 61 matching lines @@
 
  private:
   MarkCompactCollector* collector_;
 };
 
 V8_EXPORT_PRIVATE const char* AllocationSpaceName(AllocationSpace space);
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_MARK_COMPACT_H_