Update use lists after eliminating redundant phis.

runtime/vm/compiler.cc

Index: runtime/vm/compiler.cc
===================================================================
--- runtime/vm/compiler.cc	(revision 37223)
+++ runtime/vm/compiler.cc	(working copy)
@@ -479,6 +479,7 @@
         optimizer.EliminateEnvironments();
 
         DeadCodeElimination::EliminateDeadPhis(flow_graph);
+        DEBUG_ASSERT(flow_graph->VerifyUseLists());

[Ivan Posva, 2014/06/11 15:20:50]

What exactly is a DEBUG_ASSERT and why is it being used in this file?

[Florian Schneider, 2014/06/11 15:30:31]

// DEBUG_ASSERT allows identifiers in condition to be undeclared in release
// mode.

[Ivan Posva, 2014/06/11 16:25:24]

See followup CL, which removes the unnecessary use of DEBUG_ASSERT here.

 
         // Attempt to sink allocations of temporary non-escaping objects to
         // the deoptimization path.
@@ -489,6 +490,7 @@
           sinking = new AllocationSinking(flow_graph);
           sinking->Optimize();
         }
+        DEBUG_ASSERT(flow_graph->VerifyUseLists());
 
         // Ensure that all phis inserted by optimization passes have consistent
         // representations.