VM: Fix bug that can causes infinite opt/deopt loop.

runtime/vm/redundancy_elimination.cc

 // Copyright (c) 2016, 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/redundancy_elimination.h"
 
 #include "vm/bit_vector.h"
 #include "vm/flow_graph.h"
 #include "vm/hash_map.h"
 #include "vm/il_printer.h"
@@ skipping 1335 matching lines @@
                  BlockEntryInstr* pre_header,
                  Instruction* current) {
   if (current->IsCheckClass()) {
     current->AsCheckClass()->set_licm_hoisted(true);
   } else if (current->IsCheckSmi()) {
     current->AsCheckSmi()->set_licm_hoisted(true);
   } else if (current->IsCheckEitherNonSmi()) {
     current->AsCheckEitherNonSmi()->set_licm_hoisted(true);
   } else if (current->IsCheckArrayBound()) {
     current->AsCheckArrayBound()->set_licm_hoisted(true);
+  } else if (current->IsTestCids()) {
+    current->AsTestCids()->set_licm_hoisted(true);
   }
   if (FLAG_trace_optimization) {
     THR_Print("Hoisting instruction %s:%" Pd " from B%" Pd " to B%" Pd "\n",
               current->DebugName(),
               current->GetDeoptId(),
               current->GetBlock()->block_id(),
               pre_header->block_id());
   }
   // Move the instruction out of the loop.
   current->RemoveEnvironment();
@@ skipping 2095 matching lines @@
         join->phis_ = NULL;
       } else {
         join->phis_->TruncateTo(to_index);
       }
     }
   }
 }
 
 
 }  // namespace dart