Immediatelly promote marked objects

src/heap/scavenger-inl.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_SCAVENGER_INL_H_
 #define V8_HEAP_SCAVENGER_INL_H_
 
 #include "src/heap/scavenger.h"
 
 namespace v8 {
@@ skipping 21 matching lines @@
   object->GetHeap()->UpdateAllocationSite<Heap::kGlobal>(
       object, object->GetHeap()->global_pretenuring_feedback_);
 
   // 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);
 }
 
 SlotCallbackResult Scavenger::CheckAndScavengeObject(
     Heap* heap, Address slot_address, PromotionMode promotion_mode) {

[ulan, 2016/05/24 16:41:59]

Callers of this function should be changed too.

Instead of DEFAULT_PROMOTION we need to pass PROMOTE_MARKED or DEFAULT_PROMOTION
depending on incremental marking state.

   Object** slot = reinterpret_cast<Object**>(slot_address);
   Object* object = *slot;
   if (heap->InFromSpace(object)) {
     HeapObject* heap_object = reinterpret_cast<HeapObject*>(object);
     DCHECK(heap_object->IsHeapObject());
 
     ScavengeObject(reinterpret_cast<HeapObject**>(slot), heap_object,
                    promotion_mode);
 
     object = *slot;
     // If the object was in from space before and is after executing the
     // callback in to space, the object is still live.
     // Unfortunately, we do not know about the slot. It could be in a
     // just freed free space object.
     if (heap->InToSpace(object)) {
       return KEEP_SLOT;
     }
   } else {
     DCHECK(!heap->InNewSpace(object));
   }
   return REMOVE_SLOT;
 }
 
 // static
 void StaticScavengeVisitor::VisitPointer(Heap* heap, HeapObject* obj,
                                          Object** p) {
   Object* object = *p;
   if (!heap->InNewSpace(object)) return;
+  PromotionMode promotion_mode = heap->incremental_marking()->IsMarking()
+                                     ? PROMOTE_MARKED
+                                     : DEFAULT_PROMOTION;
   Scavenger::ScavengeObject(reinterpret_cast<HeapObject**>(p),
                             reinterpret_cast<HeapObject*>(object),
-                            DEFAULT_PROMOTION);
+                            promotion_mode);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_SCAVENGER_INL_H_