Immediatelly promote marked objects

src/heap/scavenger-inl.h

Index: src/heap/scavenger-inl.h
diff --git a/src/heap/scavenger-inl.h b/src/heap/scavenger-inl.h
index 3b96f648f79a818121e2076d961687680aed2bf3..702e736cebb31f3885c4c2015f9113fa16076157 100644
--- a/src/heap/scavenger-inl.h
+++ b/src/heap/scavenger-inl.h
@@ -10,8 +10,8 @@
 namespace v8 {
 namespace internal {
 
-void Scavenger::ScavengeObject(HeapObject** p, HeapObject* object,
-                               PromotionMode promotion_mode) {
+template <PromotionMode promotion_mode>
+void Scavenger::ScavengeObject(HeapObject** p, HeapObject* object) {
   DCHECK(object->GetIsolate()->heap()->InFromSpace(object));
 
   // We use the first word (where the map pointer usually is) of a heap
@@ -35,7 +35,18 @@ void Scavenger::ScavengeObject(HeapObject** p, HeapObject* object,
   // AllocationMementos are unrooted and shouldn't survive a scavenge
   DCHECK(object->map() != object->GetHeap()->allocation_memento_map());
   // Call the slow part of scavenge object.
-  return ScavengeObjectSlow(p, object, promotion_mode);
+  return ScavengeObjectSlow<promotion_mode>(p, object);
+}
+
+// static
+template <PromotionMode promotion_mode>

[ulan, 2016/06/01 09:09:40]

promotion_mode is not used in this function, so you could remove it and also
remove the mode from callers.

[Marcel Hlopko, 2016/06/01 09:19:50]

Aah sorry for not noticing this. Done.

+void Scavenger::ScavengeObjectSlow(HeapObject** p, HeapObject* object) {
+  SLOW_DCHECK(object->GetIsolate()->heap()->InFromSpace(object));
+  MapWord first_word = object->map_word();
+  SLOW_DCHECK(!first_word.IsForwardingAddress());
+  Map* map = first_word.ToMap();
+  Scavenger* scavenger = map->GetHeap()->scavenge_collector_;
+  scavenger->scavenging_visitors_table_.GetVisitor(map)(map, p, object);
 }
 
 SlotCallbackResult Scavenger::CheckAndScavengeObject(
@@ -46,8 +57,13 @@ SlotCallbackResult Scavenger::CheckAndScavengeObject(
     HeapObject* heap_object = reinterpret_cast<HeapObject*>(object);
     DCHECK(heap_object->IsHeapObject());
 
-    ScavengeObject(reinterpret_cast<HeapObject**>(slot), heap_object,
-                   promotion_mode);
+    if (promotion_mode == PROMOTE_MARKED) {
+      ScavengeObject<PROMOTE_MARKED>(reinterpret_cast<HeapObject**>(slot),
+                                     heap_object);
+    } else {
+      ScavengeObject<DEFAULT_PROMOTION>(reinterpret_cast<HeapObject**>(slot),
+                                        heap_object);
+    }
 
     object = *slot;
     // If the object was in from space before and is after executing the
@@ -64,13 +80,14 @@ SlotCallbackResult Scavenger::CheckAndScavengeObject(
 }
 
 // static
-void StaticScavengeVisitor::VisitPointer(Heap* heap, HeapObject* obj,
-                                         Object** p) {
+template <PromotionMode promotion_mode>
+void StaticScavengeVisitor<promotion_mode>::VisitPointer(Heap* heap,
+                                                         HeapObject* obj,
+                                                         Object** p) {
   Object* object = *p;
   if (!heap->InNewSpace(object)) return;
-  Scavenger::ScavengeObject(reinterpret_cast<HeapObject**>(p),
-                            reinterpret_cast<HeapObject*>(object),
-                            DEFAULT_PROMOTION);
+  Scavenger::ScavengeObject<promotion_mode>(
+      reinterpret_cast<HeapObject**>(p), reinterpret_cast<HeapObject*>(object));
 }
 
 }  // namespace internal