break;
case SparkOptions.propagator_worklist:
propagator[0] = new PropWorklist( pag );
break;
case SparkOptions.propagator_cycle:
propagator[0] = new PropCycle( pag );
break;
case SparkOptions.propagator_merge:
propagator[0] = new PropMerge( pag );
break;
case SparkOptions.propagator_alias: