Add a generic remembered set class.

src/heap/spaces.cc

 // Copyright 2011 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.
 
 #include "src/heap/spaces.h"
 
 #include "src/base/bits.h"
 #include "src/base/platform/platform.h"
 #include "src/full-codegen/full-codegen.h"
 #include "src/heap/slot-set.h"
@@ skipping 448 matching lines @@
 
   chunk->heap_ = heap;
   chunk->size_ = size;
   chunk->area_start_ = area_start;
   chunk->area_end_ = area_end;
   chunk->flags_ = 0;
   chunk->set_owner(owner);
   chunk->InitializeReservedMemory();
   chunk->slots_buffer_ = nullptr;
   chunk->old_to_new_slots_ = nullptr;
+  chunk->old_to_old_slots_ = nullptr;
   chunk->skip_list_ = nullptr;
   chunk->write_barrier_counter_ = kWriteBarrierCounterGranularity;
   chunk->progress_bar_ = 0;
   chunk->high_water_mark_.SetValue(static_cast<intptr_t>(area_start - base));
   chunk->concurrent_sweeping_state().SetValue(kSweepingDone);
   chunk->parallel_compaction_state().SetValue(kCompactingDone);
   chunk->mutex_ = nullptr;
   chunk->available_in_small_free_list_ = 0;
   chunk->available_in_medium_free_list_ = 0;
   chunk->available_in_large_free_list_ = 0;
@@ skipping 448 matching lines @@
   }
   chunk->IncrementLiveBytes(by);
 }
 
 
 void MemoryChunk::ReleaseAllocatedMemory() {
   delete slots_buffer_;
   delete skip_list_;
   delete mutex_;
   ReleaseOldToNewSlots();
+  ReleaseOldToOldSlots();
+}
+
+static SlotSet* AllocateSlotSet(size_t size, Address page_start) {
+  size_t pages = (size + Page::kPageSize - 1) / Page::kPageSize;
+  DCHECK(pages > 0);
+  SlotSet* slot_set = new SlotSet[pages];
+  for (size_t i = 0; i < pages; i++) {
+    slot_set[i].SetPageStart(page_start + i * Page::kPageSize);
+  }
+  return slot_set;
 }
 
 void MemoryChunk::AllocateOldToNewSlots() {
-  size_t pages = (size_ + Page::kPageSize - 1) / Page::kPageSize;
-  DCHECK(owner() == heap_->lo_space() || pages == 1);
-  DCHECK(pages > 0);
   DCHECK(nullptr == old_to_new_slots_);
-  old_to_new_slots_ = new SlotSet[pages];
-  for (size_t i = 0; i < pages; i++) {
-    old_to_new_slots_[i].SetPageStart(address() + i * Page::kPageSize);
-  }
+  old_to_new_slots_ = AllocateSlotSet(size_, address());
 }
 
 void MemoryChunk::ReleaseOldToNewSlots() {
   delete[] old_to_new_slots_;
   old_to_new_slots_ = nullptr;
 }
 
+void MemoryChunk::AllocateOldToOldSlots() {
+  DCHECK(nullptr == old_to_old_slots_);
+  old_to_old_slots_ = AllocateSlotSet(size_, address());
+}
+
+void MemoryChunk::ReleaseOldToOldSlots() {
+  delete[] old_to_old_slots_;
+  old_to_old_slots_ = nullptr;
+}
 
 // -----------------------------------------------------------------------------
 // PagedSpace implementation
 
 STATIC_ASSERT(static_cast<ObjectSpace>(1 << AllocationSpace::NEW_SPACE) ==
               ObjectSpace::kObjectSpaceNewSpace);
 STATIC_ASSERT(static_cast<ObjectSpace>(1 << AllocationSpace::OLD_SPACE) ==
               ObjectSpace::kObjectSpaceOldSpace);
 STATIC_ASSERT(static_cast<ObjectSpace>(1 << AllocationSpace::CODE_SPACE) ==
               ObjectSpace::kObjectSpaceCodeSpace);
@@ skipping 2269 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8