[heap] Factor out marking state of array buffer tracker

BUG=chromium:651354

Review-Url: https://codereview.chromium.org/2870683003
Cr-Commit-Position: refs/heads/master@{#45184}

src/heap/array-buffer-tracker.cc

@@ -5,6 +5,7 @@
 #include "src/heap/array-buffer-tracker.h"
 #include "src/heap/array-buffer-tracker-inl.h"
 #include "src/heap/heap.h"
+#include "src/heap/spaces.h"
 
 namespace v8 {
 namespace internal {
@@ -13,16 +14,13 @@ LocalArrayBufferTracker::~LocalArrayBufferTracker() {
   CHECK(array_buffers_.empty());
 }
 
-template <LocalArrayBufferTracker::FreeMode free_mode>
-void LocalArrayBufferTracker::Free() {
+template <typename Callback>
+void LocalArrayBufferTracker::Free(Callback should_free) {
   size_t freed_memory = 0;
   for (TrackingData::iterator it = array_buffers_.begin();
        it != array_buffers_.end();) {
     JSArrayBuffer* buffer = reinterpret_cast<JSArrayBuffer*>(it->first);
-    // TODO(mlippautz): Create a dependency on the collector to avoid getting
-    // the marking state out of thin air.
-    if ((free_mode == kFreeAll) ||
-        ObjectMarking::IsWhite(buffer, MarkingState::Internal(buffer))) {
+    if (should_free(buffer)) {
       const size_t len = it->second;
       heap_->isolate()->array_buffer_allocator()->Free(buffer->backing_store(),
                                                        len);
@@ -88,12 +86,14 @@ void ArrayBufferTracker::FreeDeadInNewSpace(Heap* heap) {
   heap->account_external_memory_concurrently_freed();
 }
 
-void ArrayBufferTracker::FreeDead(Page* page) {
+void ArrayBufferTracker::FreeDead(Page* page,
+                                  const MarkingState& marking_state) {
   // Callers need to ensure having the page lock.
   LocalArrayBufferTracker* tracker = page->local_tracker();
   if (tracker == nullptr) return;
-  DCHECK(!page->SweepingDone());
-  tracker->Free<LocalArrayBufferTracker::kFreeDead>();
+  tracker->Free([&marking_state](JSArrayBuffer* buffer) {
+    return ObjectMarking::IsWhite(buffer, marking_state);
+  });
   if (tracker->IsEmpty()) {
     page->ReleaseLocalTracker();
   }
@@ -102,7 +102,7 @@ void ArrayBufferTracker::FreeDead(Page* page) {
 void ArrayBufferTracker::FreeAll(Page* page) {
   LocalArrayBufferTracker* tracker = page->local_tracker();
   if (tracker == nullptr) return;
-  tracker->Free<LocalArrayBufferTracker::kFreeAll>();
+  tracker->Free([](JSArrayBuffer* buffer) { return true; });
   if (tracker->IsEmpty()) {
     page->ReleaseLocalTracker();
   }

src/heap/array-buffer-tracker.h

@@ -16,6 +16,7 @@ namespace internal {
 
 class Heap;
 class JSArrayBuffer;
+class MarkingState;
 class Page;
 
 class ArrayBufferTracker : public AllStatic {
@@ -40,7 +41,7 @@ class ArrayBufferTracker : public AllStatic {
   // Frees all backing store pointers for dead JSArrayBuffer on a given page.
   // Requires marking information to be present. Requires the page lock to be
   // taken by the caller.
-  static void FreeDead(Page* page);
+  static void FreeDead(Page* page, const MarkingState& marking_state);
 
   // Frees all remaining, live or dead, array buffers on a page. Only useful
   // during tear down.
@@ -71,9 +72,15 @@ class LocalArrayBufferTracker {
   inline void Add(Key key, const Value& value);
   inline Value Remove(Key key);
 
-  // Frees up array buffers determined by |free_mode|.
-  template <FreeMode free_mode>
-  void Free();
+  // Frees up array buffers.
+  //
+  // Sample usage:
+  // Free([](HeapObject* array_buffer) {
+  //    if (should_free_internal(array_buffer)) return true;
+  //    return false;
+  // });
+  template <typename Callback>
+  void Free(Callback should_free);
 
   // Processes buffers one by one. The CallbackResult of the callback decides
   // what action to take on the buffer.

src/heap/mark-compact.cc

@@ -3784,6 +3784,9 @@ int MarkCompactCollector::Sweeper::RawSweep(
          space->identity() == CODE_SPACE || space->identity() == MAP_SPACE);
   DCHECK(!p->IsEvacuationCandidate() && !p->SweepingDone());
 
+  // Sweeper takes the marking state of the full collector.
+  const MarkingState state = MarkingState::Internal(p);
+
   // If there are old-to-new slots in that page, we have to filter out slots
   // that are in dead memory which is freed by the sweeper.
   ClearOldToNewSlotsMode slots_clearing_mode = GetClearOldToNewSlotsMode(p);
@@ -3793,7 +3796,7 @@ int MarkCompactCollector::Sweeper::RawSweep(
 
   // Before we sweep objects on the page, we free dead array buffers which
   // requires valid mark bits.
-  ArrayBufferTracker::FreeDead(p);
+  ArrayBufferTracker::FreeDead(p, state);
 
   Address free_start = p->area_start();
   DCHECK(reinterpret_cast<intptr_t>(free_start) % (32 * kPointerSize) == 0);
@@ -3812,11 +3815,11 @@ int MarkCompactCollector::Sweeper::RawSweep(
   intptr_t max_freed_bytes = 0;
   int curr_region = -1;
 
-  LiveObjectIterator<kBlackObjects> it(p, MarkingState::Internal(p));
+  LiveObjectIterator<kBlackObjects> it(p, state);
   HeapObject* object = NULL;
 
   while ((object = it.Next()) != NULL) {
-    DCHECK(ObjectMarking::IsBlack(object, MarkingState::Internal(object)));
+    DCHECK(ObjectMarking::IsBlack(object, state));
     Address free_end = object->address();
     if (free_end != free_start) {
       CHECK_GT(free_end, free_start);
@@ -3890,7 +3893,7 @@ int MarkCompactCollector::Sweeper::RawSweep(
   }
 
   // Clear the mark bits of that page and reset live bytes count.
-  MarkingState::Internal(p).ClearLiveness();
+  state.ClearLiveness();
 
   p->concurrent_sweeping_state().SetValue(Page::kSweepingDone);
   if (free_list_mode == IGNORE_FREE_LIST) return 0;