Reland "[heap] Fine-grained JSArrayBuffer tracking"

src/heap/spaces.h

 // 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.
 
 #ifndef V8_HEAP_SPACES_H_
 #define V8_HEAP_SPACES_H_
 
 #include <list>
 
 #include "src/allocation.h"
 #include "src/base/atomic-utils.h"
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/base/platform/mutex.h"
 #include "src/flags.h"
 #include "src/hashmap.h"
 #include "src/list.h"
 #include "src/objects.h"
 #include "src/utils.h"
 
 namespace v8 {
 namespace internal {
 
 class AllocationInfo;
 class AllocationObserver;
 class CompactionSpace;
 class CompactionSpaceCollection;
 class FreeList;
 class Isolate;
+class LocalArrayBufferTracker;
 class MemoryAllocator;
 class MemoryChunk;
 class Page;
 class PagedSpace;
 class SemiSpace;
 class SkipList;
 class SlotsBuffer;
 class SlotSet;
 class TypedSlotSet;
 class Space;
@@ skipping 481 matching lines @@
   static const size_t kMinHeaderSize =
       kWriteBarrierCounterOffset +
       kIntptrSize         // intptr_t write_barrier_counter_
       + kPointerSize      // AtomicValue high_water_mark_
       + kPointerSize      // base::Mutex* mutex_
       + kPointerSize      // base::AtomicWord concurrent_sweeping_
       + 2 * kPointerSize  // AtomicNumber free-list statistics
       + kPointerSize      // AtomicValue next_chunk_
       + kPointerSize      // AtomicValue prev_chunk_
       // FreeListCategory categories_[kNumberOfCategories]
-      + FreeListCategory::kSize * kNumberOfCategories;
+      + FreeListCategory::kSize * kNumberOfCategories +
+      kPointerSize;  // LocalArrayBufferTracker* local_tracker_;
 
   // We add some more space to the computed header size to amount for missing
   // alignment requirements in our computation.
   // Try to get kHeaderSize properly aligned on 32-bit and 64-bit machines.
   static const size_t kHeaderSize = kMinHeaderSize;
 
   static const int kBodyOffset =
       CODE_POINTER_ALIGN(kHeaderSize + Bitmap::kSize);
 
   // The start offset of the object area in a page. Aligned to both maps and
@@ skipping 89 matching lines @@
   inline void set_skip_list(SkipList* skip_list) { skip_list_ = skip_list; }
 
   inline SlotSet* old_to_new_slots() { return old_to_new_slots_; }
   inline SlotSet* old_to_old_slots() { return old_to_old_slots_; }
   inline TypedSlotSet* typed_old_to_new_slots() {
     return typed_old_to_new_slots_;
   }
   inline TypedSlotSet* typed_old_to_old_slots() {
     return typed_old_to_old_slots_;
   }
+  inline LocalArrayBufferTracker* local_tracker() { return local_tracker_; }
 
   void AllocateOldToNewSlots();
   void ReleaseOldToNewSlots();
   void AllocateOldToOldSlots();
   void ReleaseOldToOldSlots();
   void AllocateTypedOldToNewSlots();
   void ReleaseTypedOldToNewSlots();
   void AllocateTypedOldToOldSlots();
   void ReleaseTypedOldToOldSlots();
+  void AllocateLocalTracker();
+  void ReleaseLocalTracker();
 
   Address area_start() { return area_start_; }
   Address area_end() { return area_end_; }
   int area_size() { return static_cast<int>(area_end() - area_start()); }
 
   bool CommitArea(size_t requested);
 
   // Approximate amount of physical memory committed for this chunk.
   size_t CommittedPhysicalMemory();
 
@@ skipping 166 matching lines @@
   base::AtomicNumber<intptr_t> available_in_free_list_;
   base::AtomicNumber<intptr_t> wasted_memory_;
 
   // next_chunk_ holds a pointer of type MemoryChunk
   base::AtomicValue<MemoryChunk*> next_chunk_;
   // prev_chunk_ holds a pointer of type MemoryChunk
   base::AtomicValue<MemoryChunk*> prev_chunk_;
 
   FreeListCategory categories_[kNumberOfCategories];
 
+  LocalArrayBufferTracker* local_tracker_;
+
  private:
   void InitializeReservedMemory() { reservation_.Reset(); }
 
   friend class MemoryAllocator;
   friend class MemoryChunkValidator;
 };
 
 // -----------------------------------------------------------------------------
 // A page is a memory chunk of a size 1MB. Large object pages may be larger.
 //
@@ skipping 2301 matching lines @@
     count = 0;
   }
   // Must be small, since an iteration is used for lookup.
   static const int kMaxComments = 64;
 };
 #endif
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_SPACES_H_