[heap] Register end of black areas to support faster filtering of invalid slots.

test/cctest/heap/test-heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 6968 matching lines @@
       heap->RightTrimFixedArray<Heap::SEQUENTIAL_TO_SWEEPER>(*array, i);
       HeapObject* filler = HeapObject::FromAddress(previous);
       CHECK(filler->IsFiller());
       CHECK(Marking::IsWhite(ObjectMarking::MarkBitFrom(previous)));
     }
   }
 
   heap::GcAndSweep(heap, OLD_SPACE);
 }
 
+TEST(SlotFilteringAfterBlackAreas) {
+  FLAG_black_allocation = true;
+  CcTest::InitializeVM();
+  v8::HandleScope scope(CcTest::isolate());
+  Heap* heap = CcTest::heap();
+  Isolate* isolate = heap->isolate();
+  MarkCompactCollector* mark_compact_collector = heap->mark_compact_collector();
+  heap->CollectAllGarbage();
+
+  i::MarkCompactCollector* collector = heap->mark_compact_collector();
+  i::IncrementalMarking* marking = heap->incremental_marking();
+  if (collector->sweeping_in_progress()) {
+    collector->EnsureSweepingCompleted();
+  }
+  CHECK(marking->IsMarking() || marking->IsStopped());
+  if (marking->IsStopped()) {
+    heap->StartIncrementalMarking();
+  }
+  CHECK(marking->IsMarking());
+  marking->StartBlackAllocationForTesting();
+
+  // Ensure that we allocate a new page, set up a bump pointer area, and
+  // perform the allocation in a black area.
+  heap::SimulateFullSpace(heap->old_space());
+  Handle<FixedArray> array = isolate->factory()->NewFixedArray(10, TENURED);
+  Page* page = Page::FromAddress(array->address());
+
+  // After allocation we empty the allocation info to limit the black area
+  // only on the allocated array.
+  heap->old_space()->EmptyAllocationInfo();
+
+  // Slots in the black area are part of the black object.
+  CHECK(mark_compact_collector->IsSlotInBlackObject(page, array->address()));
+  CHECK(mark_compact_collector->IsSlotInBlackObject(
+      page, array->address() + array->Size() - kPointerSize));
+
+  // Slots after the black area are not part of the black object and have to
+  // be filtered out.
+  CHECK(!mark_compact_collector->IsSlotInBlackObject(
+      page, array->address() + array->Size()));
+}
+
 TEST(Regress618958) {
   CcTest::InitializeVM();
   v8::HandleScope scope(CcTest::isolate());
   Heap* heap = CcTest::heap();
   bool isolate_is_locked = true;
   heap->update_external_memory(100 * MB);
   int mark_sweep_count_before = heap->ms_count();
   heap->MemoryPressureNotification(MemoryPressureLevel::kCritical,
                                    isolate_is_locked);
   int mark_sweep_count_after = heap->ms_count();
@@ skipping 86 matching lines @@
       chunk, chunk->area_end() - kPointerSize, chunk->area_end());
   slots[chunk->area_end() - kPointerSize] = false;
   RememberedSet<OLD_TO_NEW>::Iterate(chunk, [&slots](Address addr) {
     CHECK(slots[addr]);
     return KEEP_SLOT;
   });
 }
 
 }  // namespace internal
 }  // namespace v8