private void RunTest(Action<ProcedureBuilder> m)
 {
     var builder = new ProcedureBuilder();
     m(builder);
     var ibdr = new IntraBlockDeadRegisters();
     var block = builder.Procedure.EntryBlock.Succ[0];
     ibdr.Apply(block);
     var sw = new StringWriter();
     block.WriteStatements(sw);
     sw.Flush();
     testResult = sw.ToString();
 }