qilin.pta.toolkits.conch.CSDG Maven / Gradle / Ivy
/* Qilin - a Java Pointer Analysis Framework
* Copyright (C) 2021-2030 Qilin developers
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3.0 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Lesser Public License for more details.
*
* You should have received a copy of the GNU General Lesser Public
* License along with this program. If not, see
* .
*/
package qilin.pta.toolkits.conch;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import qilin.core.pag.AllocNode;
import qilin.util.graph.DirectedGraphImpl;
/*
* context-sensitivity dependent graph:
* an edge l1 --> l2 means if l2 is context-insensitive, then l1 should be context-insensitive.
* if l2 is context-sensitive, then l1 also should be context-sensitive.
* if edges form a cycle, i.e, l1-->l2-->l3-->l1 and non nodes's context-sensitivity
* in this cycle could be decide yet, we assume all of them to be context-insensitive.
* To efficiently check Obs 3(b) (lines 18-23 in Algorithm 1), we introduce this graph structure.
* */
public class CSDG extends DirectedGraphImpl {
/*
* Remove node on the graph that does not have successor.
* */
public void removeNode(final AllocNode to) {
if (succs.containsKey(to) && !succs.get(to).isEmpty()) {
return;
}
succs.remove(to);
if (preds.containsKey(to)) {
for (AllocNode from : preds.get(to)) {
succs.get(from).remove(to);
}
preds.remove(to);
}
nodes.remove(to);
}
public Set noOutDegreeNodes() {
Set ret = new HashSet<>();
for (AllocNode node : allNodes()) {
if (succs.getOrDefault(node, Collections.emptySet()).isEmpty()) {
ret.add(node);
}
}
return ret;
}
}