[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 c8c4d3f5bbd6dd7d97a1d471377e94bf4f416ef4..ae2ff5af9e04f4bf5f7f5f4a6f0f30df72a9c360 100644
--- a/src/heap/spaces.h
+++ b/src/heap/spaces.h
@@ -14,6 +14,7 @@
 #include "src/base/platform/mutex.h"
 #include "src/flags.h"
 #include "src/hashmap.h"
+#include "src/heap/array-buffer-tracker.h"
 #include "src/list.h"
 #include "src/objects.h"
 #include "src/utils.h"
@@ -522,7 +523,8 @@ class MemoryChunk {
       + kPointerSize      // AtomicValue next_chunk_
       + kPointerSize      // AtomicValue prev_chunk_
       // FreeListCategory categories_[kNumberOfCategories]
-      + FreeListCategory::kSize * kNumberOfCategories;
+      + FreeListCategory::kSize * kNumberOfCategories +
+      kPointerSize;  // LocalArrayBufferTracker tracker_
 
   // We add some more space to the computed header size to amount for missing
   // alignment requirements in our computation.
@@ -817,6 +819,8 @@ class MemoryChunk {
 
   FreeListCategory categories_[kNumberOfCategories];
 
+  LocalArrayBufferTracker* local_tracker_;
+
  private:
   void InitializeReservedMemory() { reservation_.Reset(); }
 
@@ -947,6 +951,23 @@ class Page : public MemoryChunk {
     available_in_free_list_.Increment(available);
   }
 
+  LocalArrayBufferTracker* local_tracker() {
+    if (local_tracker_ == nullptr) {
+      local_tracker_ = new LocalArrayBufferTracker(heap_);
+    }
+    return local_tracker_;
+  }
+
+  void FreeDeadArraybuffersAndResetTracker() {
+    if (local_tracker_ != nullptr) {
+      local_tracker_->FreeDeadAndReset();
+      if (local_tracker_->IsEmpty()) {
+        delete local_tracker_;
+        local_tracker_ = nullptr;
+      }
+    }
+  }
+
 #ifdef DEBUG
   void Print();
 #endif  // DEBUG
@@ -2859,6 +2880,9 @@ class NewSpace : public Space {
   void PauseAllocationObservers() override;
   void ResumeAllocationObservers() override;
 
+  SemiSpace* from_space() { return &from_space_; }
+  SemiSpace* to_space() { return &to_space_; }
+
  private:
   // Update allocation info to match the current to-space page.
   void UpdateAllocationInfo();