Do not left-trim arrays when concurrent sweeping is active.

src/mark-compact.h

Index: src/mark-compact.h
diff --git a/src/mark-compact.h b/src/mark-compact.h
index 0ebe8a0f747846193bfd0002cccd8bec247df4a0..165eab88dcb99c1c1c35dcd3f8702be7e3e3a627 100644
--- a/src/mark-compact.h
+++ b/src/mark-compact.h
@@ -738,6 +738,8 @@ class MarkCompactCollector {
     return sequential_sweeping_;
   }
 
+  bool CanMoveObjectStart(HeapObject* object);

[Michael Starzinger, 2014/03/24 12:21:35]

nit: Shouldn't this actually be a predicate on the Heap class instead of the
MarkCompactCollector class?

[Hannes Payer (out of office), 2014/03/25 11:41:08]

Done.

+
   // Mark the global table which maps weak objects to dependent code without
   // marking its contents.
   void MarkWeakObjectToCodeTable();