[heap] Provide ObjectMarking with marking transitions

src/heap/mark-compact-inl.h

Index: src/heap/mark-compact-inl.h
diff --git a/src/heap/mark-compact-inl.h b/src/heap/mark-compact-inl.h
index 1973753b0c3ae9ed0234b68b7d663135da155add..2c5d1eddaa80a85da6170305aa5193ded82562e2 100644
--- a/src/heap/mark-compact-inl.h
+++ b/src/heap/mark-compact-inl.h
@@ -14,11 +14,8 @@ namespace internal {
 
 void MarkCompactCollector::PushBlack(HeapObject* obj) {
   DCHECK(Marking::IsBlack(ObjectMarking::MarkBitFrom(obj)));

[Hannes Payer (out of office), 2017/01/18 14:43:35]

That would also short cut the double accessors: ObjectMarking::IsBlack(obj)

[Michael Lippautz, 2017/01/18 15:58:07]

Done.

-  if (marking_deque()->Push(obj)) {
-    MemoryChunk::IncrementLiveBytes(obj, obj->Size());
-  } else {
-    MarkBit mark_bit = ObjectMarking::MarkBitFrom(obj);
-    Marking::BlackToGrey(mark_bit);
+  if (!marking_deque()->Push(obj)) {
+    ObjectMarking::BlackToGrey(obj);
   }
 }
 
@@ -26,9 +23,7 @@ void MarkCompactCollector::PushBlack(HeapObject* obj) {
 void MarkCompactCollector::UnshiftBlack(HeapObject* obj) {
   DCHECK(Marking::IsBlack(ObjectMarking::MarkBitFrom(obj)));
   if (!marking_deque()->Unshift(obj)) {
-    MemoryChunk::IncrementLiveBytes(obj, -obj->Size());
-    MarkBit mark_bit = ObjectMarking::MarkBitFrom(obj);
-    Marking::BlackToGrey(mark_bit);
+    ObjectMarking::BlackToGrey(obj);
   }
 }
 
@@ -36,18 +31,16 @@ void MarkCompactCollector::UnshiftBlack(HeapObject* obj) {
 void MarkCompactCollector::MarkObject(HeapObject* obj, MarkBit mark_bit) {
   DCHECK(ObjectMarking::MarkBitFrom(obj) == mark_bit);
   if (Marking::IsWhite(mark_bit)) {
-    Marking::WhiteToBlack(mark_bit);
-    DCHECK(obj->GetIsolate()->heap()->Contains(obj));
+    ObjectMarking::WhiteToBlack(obj);
     PushBlack(obj);
   }
 }
 
 
 void MarkCompactCollector::SetMark(HeapObject* obj, MarkBit mark_bit) {
-  DCHECK(Marking::IsWhite(mark_bit));
+  DCHECK(Marking::IsWhite(ObjectMarking::MarkBitFrom(obj)));
   DCHECK(ObjectMarking::MarkBitFrom(obj) == mark_bit);
-  Marking::WhiteToBlack(mark_bit);
-  MemoryChunk::IncrementLiveBytes(obj, obj->Size());
+  ObjectMarking::WhiteToBlack(obj);
 }