diff --git a/src/heap/scavenger-inl.h b/src/heap/scavenger-inl.h
index b8fd1c8..0b6a0f4 100644
--- a/src/heap/scavenger-inl.h
+++ b/src/heap/scavenger-inl.h
@@ -37,10 +37,35 @@
   return ScavengeObjectSlow(p, object);
 }
 
+SlotCallbackResult Scavenger::CheckAndScavengeObject(Heap* heap,
+                                                     Address slot_address) {
+  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);
+
+    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) {
+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),