/*
* This file is part of the Jikes RVM project (http://jikesrvm.org).
*
* This file is licensed to You under the Eclipse Public License (EPL);
* You may not use this file except in compliance with the License. You
* may obtain a copy of the License at
*
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership.
*/
package org.jikesrvm.compilers.opt.util;
/**
* Interface to allow building top-sort, by calling TopSort.buildTopSort()
* 5/25/1999
*/
public interface TopSortInterface {
/**
* Return the start node if forward = true for forward topsort,
* and return the end node if forward = false for backward topsort.
* @param forward whether we are viewing the graph in the forward direction
* @return the start node if forward = true for forward topsort,
* the end node if forward = false for backward topsort.
*/
SortedGraphNode startNode(boolean forward);
/**
* Return the number of nodes in the graph
* @return the number of nodes in the graph
*/
int numberOfNodes();
/**
* Return true if no resetTopSorted(forward) has been executed
* since the last setTopSorted(forward) has been executed
* @param forward whether we are viewing the graph in the forward direction
* @return true if no resetTopSorted(forward) has been executed
* since the last setTopSorted(forward) has been executed
*/
boolean isTopSorted(boolean forward);
/**
* Should have a side effect such that isTopSorted(forward)
* returns the correct value.
* @param forward whether we are viewing the graph in the forward direction
*/
void setTopSorted(boolean forward);
/**
* Should have a side effect such that isTopSorted(forward)
* returns the correct value.
*/
void resetTopSorted();
}