ArrayList preds = block.getPredecessors();
List preds = block.getPredecessors();
	public void addPredecessor(BasicBlock block) {		if (!this.predecessors.contains(block)) {			this.predecessors.add(block);		}		// Closure		ArrayList preds = block.getPredecessors();		int n = preds.size();		for (int i=0; i<n; i+=1) {			BasicBlock pred = (BasicBlock) preds.get(i);			if (!predecessors.contains(pred)) {				addPredecessor(pred);			}			pred.addSuccessor(this);		}	}