Revert of [heap] Reland "Remove black pages and use black areas instead."

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index b16778f86f596662d35087d7e390cd88c1957254..8ce59d53a339ac2a3f990d0ca8321fd7de8a1d62 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -3066,16 +3066,6 @@
   if (mode == ClearRecordedSlots::kYes) {
     ClearRecordedSlotRange(addr, addr + size);
   }
-
-  // If the location where the filler is created is within a black area we have
-  // to clear the mark bits of the filler space.
-  if (incremental_marking()->black_allocation() &&
-      Marking::IsBlackOrGrey(ObjectMarking::MarkBitFrom(addr))) {
-    Page* page = Page::FromAddress(addr);
-    page->markbits()->ClearRange(page->AddressToMarkbitIndex(addr),
-                                 page->AddressToMarkbitIndex(addr + size));
-  }
-
   // At this point, we may be deserializing the heap from a snapshot, and
   // none of the maps have been created yet and are NULL.
   DCHECK((filler->map() == NULL && !deserialization_complete_) ||
@@ -3146,20 +3136,13 @@
   DCHECK(elements_to_trim <= len);
 
   // Calculate location of new array start.
-  Address old_start = object->address();
-  Address new_start = old_start + bytes_to_trim;
-
-  // Transfer the mark bits to their new location if the object is not within
-  // a black area.
-  if (!incremental_marking()->black_allocation() ||
-      !Marking::IsBlack(ObjectMarking::MarkBitFrom(new_start))) {
-    IncrementalMarking::TransferMark(this, old_start, new_start);
-  }
+  Address new_start = object->address() + bytes_to_trim;
 
   // Technically in new space this write might be omitted (except for
   // debug mode which iterates through the heap), but to play safer
   // we still do it.
-  CreateFillerObjectAt(old_start, bytes_to_trim, ClearRecordedSlots::kYes);
+  CreateFillerObjectAt(object->address(), bytes_to_trim,
+                       ClearRecordedSlots::kYes);
   // Initialize header of the trimmed array. Since left trimming is only
   // performed on pages which are not concurrently swept creating a filler
   // object does not require synchronization.
@@ -3168,17 +3151,17 @@
   int new_start_index = elements_to_trim * (element_size / kPointerSize);
   former_start[new_start_index] = map;
   former_start[new_start_index + 1] = Smi::FromInt(len - elements_to_trim);
-
   FixedArrayBase* new_object =
       FixedArrayBase::cast(HeapObject::FromAddress(new_start));
-
-  // Maintain consistency of live bytes during incremental marking
-  AdjustLiveBytes(new_object, -bytes_to_trim, Heap::CONCURRENT_TO_SWEEPER);
 
   // Remove recorded slots for the new map and length offset.
   ClearRecordedSlot(new_object, HeapObject::RawField(new_object, 0));
   ClearRecordedSlot(new_object, HeapObject::RawField(
                                     new_object, FixedArrayBase::kLengthOffset));
+
+  // Maintain consistency of live bytes during incremental marking
+  IncrementalMarking::TransferMark(this, object->address(), new_start);
+  AdjustLiveBytes(new_object, -bytes_to_trim, Heap::CONCURRENT_TO_SWEEPER);
 
   // Notify the heap profiler of change in object layout.
   OnMoveEvent(new_object, object, new_object->Size());
@@ -4194,13 +4177,14 @@
   // Hence we have to color all objects of the reservation first black to avoid
   // unnecessary marking deque load.
   if (incremental_marking()->black_allocation()) {
-    for (int i = OLD_SPACE; i < Serializer::kNumberOfSpaces; i++) {
+    for (int i = CODE_SPACE; i < Serializer::kNumberOfSpaces; i++) {
       const Heap::Reservation& res = reservations[i];
       for (auto& chunk : res) {
         Address addr = chunk.start;
         while (addr < chunk.end) {
           HeapObject* obj = HeapObject::FromAddress(addr);
           Marking::MarkBlack(ObjectMarking::MarkBitFrom(obj));
+          MemoryChunk::IncrementLiveBytesFromGC(obj, obj->Size());
           addr += obj->Size();
         }
       }