/** Returns a representation of a region in dot-format (graphviz). */
public String regionToDot(Region r) {
nodeCounter = 2; // counter for nodes, values 0 and 1 are used for nodes FALSE and TRUE
Map<Region, Integer> cache = new HashMap<>(); // map for same regions
StringBuilder str = new StringBuilder("digraph G {\n");
// make nodes for FALSE and TRUE
if (!r.isTrue()) {
str.append("0 [shape=box, label=\"0\", style=filled, shape=box, height=0.3, width=0.3];\n");
cache.put(makeFalse(), 0);
}
if (!r.isFalse()) {
str.append("1 [shape=box, label=\"1\", style=filled, shape=box, height=0.3, width=0.3];\n");
cache.put(makeTrue(), 1);
}
regionToDot(r, str, cache);
str.append("}\n");
return str.toString();
}
private void dumpRegion(Region r, Appendable out) throws IOException {
if (regionMap.containsValue(r)) {
out.append(regionMap.inverse().get(r));
} else if (r.isFalse()) {
out.append("FALSE");
} else if (r.isTrue()) {
out.append("TRUE");
} else {
Triple<Region, Region, Region> triple = delegate.getIfThenElse(r);
String predName = regionMap.inverse().get(triple.getFirst());
Region trueBranch = triple.getSecond();
Region falseBranch = triple.getThird();
if (trueBranch.isFalse()) {
assert !falseBranch.isFalse();
// only falseBranch is present
out.append("!").append(predName).append(" & ");
dumpRegion(falseBranch, out);
} else if (falseBranch.isFalse()) {
// only trueBranch is present
out.append(predName).append(" & ");
dumpRegion(trueBranch, out);
} else {
// both branches present
out.append("((").append(predName).append(" & ");
dumpRegion(trueBranch, out);
out.append(") | (").append("!").append(predName).append(" & ");
dumpRegion(falseBranch, out);
out.append("))");
}
}
}