Short-circuit embedded cons strings.

src/objects-visiting-inl.h

Index: src/objects-visiting-inl.h
diff --git a/src/objects-visiting-inl.h b/src/objects-visiting-inl.h
index 6c3c9d44fe318d77c141a68dc6d562d86563aceb..a4b02832b9e65a036d3fe710ee8533501942bd43 100644
--- a/src/objects-visiting-inl.h
+++ b/src/objects-visiting-inl.h
@@ -233,13 +233,11 @@ template<typename StaticVisitor>
 void StaticMarkingVisitor<StaticVisitor>::VisitEmbeddedPointer(
     Heap* heap, RelocInfo* rinfo) {
   ASSERT(rinfo->rmode() == RelocInfo::EMBEDDED_OBJECT);
-  ASSERT(!rinfo->target_object()->IsConsString());
   HeapObject* object = HeapObject::cast(rinfo->target_object());
   if (!FLAG_weak_embedded_maps_in_optimized_code || !FLAG_collect_maps ||
       rinfo->host()->kind() != Code::OPTIMIZED_FUNCTION ||
       !object->IsMap() || !Map::cast(object)->CanTransition()) {
-    heap->mark_compact_collector()->RecordRelocSlot(rinfo, object);
-    StaticVisitor::MarkObject(heap, object);
+    StaticVisitor::VisitPointer(heap, rinfo->target_object_address());

[Michael Starzinger, 2013/06/20 12:40:34]

Yes, this approach will work. But it requires a trailing update of the target
object, because on some architectures you are not going to get a direct pointer
into the code because the embedded object is stored split accross several
instructions. Something like the following is needed.

Look at PointersUpdatingVisitor::VisitEmbeddedPointer() for an example of how
this can be done.

   }
 }