visit(cfg.getEntry());
visitAll();
	public DepthFirstSearch search() {		// Control flow graphs have a unique entry block		// from which all other blocks can be reached,		// so there's no need to iterate over start blocks		// (as is needed in more general graph traversals).		visit(cfg.getEntry());		// Classify CROSS and FORWARD edges		classifyUnknownEdges();		return this;	}