Reland "[heap] Fine-grained JSArrayBuffer tracking"

src/heap/spaces.h

Index: src/heap/spaces.h
diff --git a/src/heap/spaces.h b/src/heap/spaces.h
index a85dce5985021bb1145334789d4f900586442252..30ffe11f888c3dfe136012a58d0660e437edb1b7 100644
--- a/src/heap/spaces.h
+++ b/src/heap/spaces.h
@@ -27,6 +27,7 @@ class CompactionSpace;
 class CompactionSpaceCollection;
 class FreeList;
 class Isolate;
+class LocalArrayBufferTracker;
 class MemoryAllocator;
 class MemoryChunk;
 class Page;
@@ -528,7 +529,8 @@ class MemoryChunk {
       + 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.
@@ -638,6 +640,7 @@ class MemoryChunk {
   inline TypedSlotSet* typed_old_to_old_slots() {
     return typed_old_to_old_slots_;
   }
+  inline LocalArrayBufferTracker* local_tracker() { return local_tracker_; }
 
   void AllocateOldToNewSlots();
   void ReleaseOldToNewSlots();
@@ -647,6 +650,8 @@ class MemoryChunk {
   void ReleaseTypedOldToNewSlots();
   void AllocateTypedOldToOldSlots();
   void ReleaseTypedOldToOldSlots();
+  void AllocateLocalTracker();
+  void ReleaseLocalTracker();
 
   Address area_start() { return area_start_; }
   Address area_end() { return area_end_; }
@@ -833,6 +838,8 @@ class MemoryChunk {
 
   FreeListCategory categories_[kNumberOfCategories];
 
+  LocalArrayBufferTracker* local_tracker_;
+
  private:
   void InitializeReservedMemory() { reservation_.Reset(); }