[heap] Fine-grained JSArrayBuffer tracking

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index afdc7bb4cd397d69625ecdca09c295a668e0a6ae..954a873dd42e8837a890bb1373cf95ce3aa03479 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -387,7 +387,7 @@ void Heap::PrintShortHeapStatistics() {
                this->CommittedMemory() / KB);
   PrintIsolate(
       isolate_, "External memory reported: %6" V8PRIdPTR " KB\n",
-      static_cast<intptr_t>(amount_of_external_allocated_memory_ / KB));
+      static_cast<intptr_t>(amount_of_external_allocated_memory_.Value() / KB));
   PrintIsolate(isolate_, "Total time spent in GC  : %.1f ms\n",
                total_gc_time_ms_);
 }
@@ -1341,7 +1341,7 @@ bool Heap::PerformGarbageCollection(
   if (collector == MARK_COMPACTOR) {
     // Register the amount of external allocated memory.
     amount_of_external_allocated_memory_at_last_global_gc_ =
-        amount_of_external_allocated_memory_;
+        amount_of_external_allocated_memory_.Value();
     SetOldGenerationAllocationLimit(old_gen_size, gc_speed, mutator_speed);
   } else if (HasLowYoungGenerationAllocationRate() &&
              old_generation_size_configured_) {
@@ -1626,8 +1626,6 @@ void Heap::Scavenge() {
 
   scavenge_collector_->SelectScavengingVisitorsTable();
 
-  array_buffer_tracker()->PrepareDiscoveryInNewSpace();
-
   // Flip the semispaces.  After flipping, to space is empty, from space has
   // live objects.
   new_space_.Flip();
@@ -1734,7 +1732,7 @@ void Heap::Scavenge() {
   // Set age mark.
   new_space_.set_age_mark(new_space_.top());
 
-  array_buffer_tracker()->FreeDead(true);
+  array_buffer_tracker()->FreeDeadInNewSpace();
 
   // Update how much has survived scavenge.
   IncrementYoungSurvivorsCounter(static_cast<int>(
@@ -2014,7 +2012,9 @@ HeapObject* Heap::DoubleAlignForDeserialization(HeapObject* object, int size) {
 
 
 void Heap::RegisterNewArrayBuffer(JSArrayBuffer* buffer) {
-  return array_buffer_tracker()->RegisterNew(buffer);
+  const bool track_live =
+      Page::FromAddress(buffer->address())->IsFlagSet(Page::BLACK_PAGE);
+  return array_buffer_tracker()->RegisterNew(buffer, track_live);
 }
 
 
@@ -5010,10 +5010,10 @@ intptr_t Heap::PromotedSpaceSizeOfObjects() {
 
 
 int64_t Heap::PromotedExternalMemorySize() {
-  if (amount_of_external_allocated_memory_ <=
+  if (amount_of_external_allocated_memory_.Value() <=
       amount_of_external_allocated_memory_at_last_global_gc_)
     return 0;
-  return amount_of_external_allocated_memory_ -
+  return amount_of_external_allocated_memory_.Value() -
          amount_of_external_allocated_memory_at_last_global_gc_;
 }