- Remember the fact that an object has been added to the

runtime/vm/gc_marker.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/gc_marker.h"
 
 #include <map>
 #include <utility>
 
 #include "vm/allocation.h"
@@ skipping 157 matching lines @@
   void MarkAndPush(RawObject* raw_obj) {
     ASSERT(raw_obj->IsHeapObject());
     ASSERT((FLAG_verify_before_gc || FLAG_verify_before_gc) ?
            page_space_->Contains(RawObject::ToAddr(raw_obj)) :
            true);
 
     // Mark the object and push it on the marking stack.
     ASSERT(!raw_obj->IsMarked());
     RawClass* raw_class = isolate()->class_table()->At(raw_obj->GetClassId());
     raw_obj->SetMarkBit();
+    raw_obj->ClearRememberedBit();
     if (raw_obj->IsWatched()) {
       std::pair<DelaySet::iterator, DelaySet::iterator> ret;
       // Visit all elements with a key equal to raw_obj.
       ret = delay_set_.equal_range(raw_obj);
       for (DelaySet::iterator it = ret.first; it != ret.second; ++it) {
         it->second->VisitPointers(this);
       }
       delay_set_.erase(ret.first, ret.second);
       raw_obj->ClearWatchedBit();
     }
     marking_stack_->Push(raw_obj);
 
     // TODO(iposva): Should we mark the classes early?
     MarkObject(raw_class, NULL);
   }
 
   void MarkObject(RawObject* raw_obj, RawObject** p) {
     // Fast exit if the raw object is a Smi.
     if (!raw_obj->IsHeapObject()) return;
 
     // Fast exit if the raw object is marked.
     if (raw_obj->IsMarked()) return;
 
     // Skip over new objects, but verify consistency of heap while at it.
     if (raw_obj->IsNewObject()) {
       // TODO(iposva): Add consistency check.
-      if (visiting_old_object_ != NULL) {
+      if ((visiting_old_object_ != NULL) &&
+          !visiting_old_object_->IsRemembered()) {
         ASSERT(p != NULL);
+        visiting_old_object_->SetRememberedBit();
         isolate()->store_buffer()->AddPointer(
             reinterpret_cast<uword>(visiting_old_object_));
       }
       return;
     }
 
     MarkAndPush(raw_obj);
   }
 
   Heap* heap_;
@@ skipping 189 matching lines @@
   DrainMarkingStack(isolate, &mark);
   IterateWeakReferences(isolate, &mark);
   MarkingWeakVisitor mark_weak;
   IterateWeakRoots(isolate, &mark_weak, invoke_api_callbacks);
   mark.Finalize();
   ProcessPeerReferents(page_space);
   Epilogue(isolate, invoke_api_callbacks);
 }
 
 }  // namespace dart