Revert of [heap] Improve size profiling for ArrayBuffer tracking

src/heap/array-buffer-tracker.cc

Index: src/heap/array-buffer-tracker.cc
diff --git a/src/heap/array-buffer-tracker.cc b/src/heap/array-buffer-tracker.cc
index bffe437c58e515f29f21b1c8c94cfd5cd1ed6b66..62b848ef70c5339bf6bd3be7585b9290a4b022fb 100644
--- a/src/heap/array-buffer-tracker.cc
+++ b/src/heap/array-buffer-tracker.cc
@@ -14,7 +14,7 @@
 }
 
 template <LocalArrayBufferTracker::FreeMode free_mode>
-LocalArrayBufferTracker::ProcessResult LocalArrayBufferTracker::Free() {
+void LocalArrayBufferTracker::Free() {
   size_t freed_memory = 0;
   for (TrackingData::iterator it = array_buffers_.begin();
        it != array_buffers_.end();) {
@@ -30,71 +30,60 @@
       ++it;
     }
   }
-  return ProcessResult(freed_memory, 0);
+  if (freed_memory > 0) {
+    heap_->update_external_memory_concurrently_freed(
+        static_cast<intptr_t>(freed_memory));
+  }
 }
 
 template <typename Callback>
-LocalArrayBufferTracker::ProcessResult LocalArrayBufferTracker::Process(
-    Callback callback) {
+void LocalArrayBufferTracker::Process(Callback callback) {
   JSArrayBuffer* new_buffer = nullptr;
   size_t freed_memory = 0;
-  size_t promoted_memory = 0;
-  size_t len = 0;
-  Page* target_page = nullptr;
-  LocalArrayBufferTracker* tracker = nullptr;
   for (TrackingData::iterator it = array_buffers_.begin();
        it != array_buffers_.end();) {
-    switch (callback(it->first, &new_buffer)) {
-      case kKeepEntry:
-        ++it;
-        break;
-      case kUpdateEntry:
-        DCHECK_NOT_NULL(new_buffer);
-        target_page = Page::FromAddress(new_buffer->address());
-        // We need to lock the target page because we cannot guarantee
-        // exclusive access to new space pages.
-        if (target_page->InNewSpace()) target_page->mutex()->Lock();
+    const CallbackResult result = callback(it->first, &new_buffer);
+    if (result == kKeepEntry) {
+      ++it;
+    } else if (result == kUpdateEntry) {
+      DCHECK_NOT_NULL(new_buffer);
+      Page* target_page = Page::FromAddress(new_buffer->address());
+      // We need to lock the target page because we cannot guarantee
+      // exclusive access to new space pages.
+      if (target_page->InNewSpace()) target_page->mutex()->Lock();
+      LocalArrayBufferTracker* tracker = target_page->local_tracker();
+      if (tracker == nullptr) {
+        target_page->AllocateLocalTracker();
         tracker = target_page->local_tracker();
-        if (tracker == nullptr) {
-          target_page->AllocateLocalTracker();
-          tracker = target_page->local_tracker();
-        }
-        DCHECK_NOT_NULL(tracker);
-        len = it->second;
-        tracker->Add(new_buffer, len);
-        if (target_page->InNewSpace()) {
-          target_page->mutex()->Unlock();
-        } else {
-          promoted_memory += len;
-        }
-        it = array_buffers_.erase(it);
-        break;
-      case kRemoveEntry:
-        len = it->second;
-        heap_->isolate()->array_buffer_allocator()->Free(
-            it->first->backing_store(), len);
-        freed_memory += len;
-        it = array_buffers_.erase(it);
-        break;
+      }
+      DCHECK_NOT_NULL(tracker);
+      tracker->Add(new_buffer, it->second);
+      if (target_page->InNewSpace()) target_page->mutex()->Unlock();
+      it = array_buffers_.erase(it);
+    } else if (result == kRemoveEntry) {
+      const size_t len = it->second;
+      heap_->isolate()->array_buffer_allocator()->Free(
+          it->first->backing_store(), len);
+      freed_memory += len;
+      it = array_buffers_.erase(it);
+    } else {
+      UNREACHABLE();
     }
   }
-  return ProcessResult(freed_memory, promoted_memory);
+  if (freed_memory > 0) {
+    heap_->update_external_memory_concurrently_freed(
+        static_cast<intptr_t>(freed_memory));
+  }
 }
 
-void ArrayBufferTracker::AccountForConcurrentlyFreedMemory() {
-  heap_->update_external_memory(
-      static_cast<int64_t>(concurrently_freed_.Value()));
-  concurrently_freed_.SetValue(0);
-}
-
-void ArrayBufferTracker::FreeDeadInNewSpace() {
-  DCHECK_EQ(heap_->gc_state(), Heap::HeapState::SCAVENGE);
-  for (Page* page : NewSpacePageRange(heap_->new_space()->FromSpaceStart(),
-                                      heap_->new_space()->FromSpaceEnd())) {
+void ArrayBufferTracker::FreeDeadInNewSpace(Heap* heap) {
+  DCHECK_EQ(heap->gc_state(), Heap::HeapState::SCAVENGE);
+  for (Page* page : NewSpacePageRange(heap->new_space()->FromSpaceStart(),
+                                      heap->new_space()->FromSpaceEnd())) {
     bool empty = ProcessBuffers(page, kUpdateForwardedRemoveOthers);
     CHECK(empty);
   }
-  AccountForConcurrentlyFreedMemory();
+  heap->account_external_memory_concurrently_freed();
 }
 
 void ArrayBufferTracker::FreeDead(Page* page) {
@@ -102,13 +91,7 @@
   LocalArrayBufferTracker* tracker = page->local_tracker();
   if (tracker == nullptr) return;
   DCHECK(!page->SweepingDone());
-  LocalArrayBufferTracker::ProcessResult result =
-      tracker->Free<LocalArrayBufferTracker::kFreeDead>();
-  if (page->InNewSpace()) {
-    retained_from_new_space_.Decrement(result.freed);
-  } else {
-    retained_from_old_space_.Decrement(result.freed);
-  }
+  tracker->Free<LocalArrayBufferTracker::kFreeDead>();
   if (tracker->IsEmpty()) {
     page->ReleaseLocalTracker();
   }
@@ -117,14 +100,7 @@
 void ArrayBufferTracker::FreeAll(Page* page) {
   LocalArrayBufferTracker* tracker = page->local_tracker();
   if (tracker == nullptr) return;
-  LocalArrayBufferTracker::ProcessResult result =
-      tracker->Free<LocalArrayBufferTracker::kFreeAll>();
-  concurrently_freed_.Increment(result.freed);
-  if (page->InNewSpace()) {
-    retained_from_new_space_.Decrement(result.freed);
-  } else {
-    retained_from_old_space_.Decrement(result.freed);
-  }
+  tracker->Free<LocalArrayBufferTracker::kFreeAll>();
   if (tracker->IsEmpty()) {
     page->ReleaseLocalTracker();
   }
@@ -135,7 +111,7 @@
   if (tracker == nullptr) return true;
 
   DCHECK(page->SweepingDone());
-  LocalArrayBufferTracker::ProcessResult result = tracker->Process(
+  tracker->Process(
       [mode](JSArrayBuffer* old_buffer, JSArrayBuffer** new_buffer) {
         MapWord map_word = old_buffer->map_word();
         if (map_word.IsForwardingAddress()) {
@@ -146,13 +122,6 @@
                    ? LocalArrayBufferTracker::kKeepEntry
                    : LocalArrayBufferTracker::kRemoveEntry;
       });
-  concurrently_freed_.Increment(result.freed);
-  if (page->InNewSpace()) {
-    retained_from_new_space_.Decrement(result.freed + result.promoted);
-  } else {
-    retained_from_old_space_.Decrement(result.freed);
-  }
-  retained_from_old_space_.Increment(result.promoted);
   return tracker->IsEmpty();
 }