RefactorSplitJoin.addDeepRectangularSyncPoints(str);
str = RefactorSplitJoin.addDeepRectangularSyncPoints(str);
    private DPConfig buildStreamConfig() {	// make canonical representation	RefactorSplitJoin.addDeepRectangularSyncPoints(str);	// dump to graph	StreamItDot.printGraph(str, "dp-partition-input.dot");	return (DPConfig)str.accept(new ConfigBuilder());    }