Fix treatment of const variables in assigned variable analysis....

src/data-flow.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1107 matching lines @@
     av_.Add(BitIndex(var));
   }
 }
 
 
 void AssignedVariablesAnalyzer::MarkIfTrivial(Expression* expr) {
   Variable* var = expr->AsVariableProxy()->AsVariable();
   if (var != NULL &&
       var->IsStackAllocated() &&
       !var->is_arguments() &&
+      var->mode() != Variable::CONST &&
       (var->is_this() || !av_.Contains(BitIndex(var)))) {
     expr->AsVariableProxy()->set_is_trivial(true);
   }
 }
 
 
 void AssignedVariablesAnalyzer::ProcessExpression(Expression* expr) {
   BitVector saved_av(av_);
   av_.Clear();
   Visit(expr);
@@ skipping 693 matching lines @@
   for (int i = postorder->length() - 1; i >= 0; i--) {
     postorder->at(i)->PrintText();
   }
 }
 
 
 #endif  // defined(DEBUG)
 
 
 } }  // namespace v8::internal