private void optimize() {
// SSS FIXME: Can't we not add some of these exception edges in the first place??
// Remove exception edges from blocks that couldn't possibly thrown an exception!
List<Edge> toRemove = new ArrayList<Edge>();
for (BasicBlock b : graph.allData()) {
boolean noExceptions = true;
for (Instr i : b.getInstrs()) {
if (i.canRaiseException()) {
noExceptions = false;
break;
}
}
if (noExceptions) {
for (Edge<BasicBlock> e : graph.vertexFor(b).getOutgoingEdgesOfType(EdgeType.EXCEPTION)) {
BasicBlock source = e.getSource().getData();
BasicBlock destination = e.getDestination().getData();
toRemove.add(e);
if (rescuerMap.get(source) == destination) rescuerMap.remove(source);
if (ensurerMap.get(source) == destination) ensurerMap.remove(source);
}
}
}
if (!toRemove.isEmpty()) {
for (Edge edge : toRemove) {
graph.removeEdge(edge);
}
}
deleteOrphanedBlocks(graph);
}
private void deleteOrphanedBlocks(DirectedGraph<BasicBlock> graph) {
// System.out.println("\nGraph:\n" + getGraph().toString());
// System.out.println("\nInstructions:\n" + toStringInstrs());
// FIXME: Quick and dirty implementation
while (true) {
BasicBlock bbToRemove = null;
for (BasicBlock b : graph.allData()) {
if (b == entryBB) continue; // Skip entry bb!
// Every other bb should have at least one incoming edge
if (graph.vertexFor(b).getIncomingEdges().isEmpty()) {
bbToRemove = b;
break;
}
}
if (bbToRemove == null) break;
removeBB(bbToRemove);
}
}
public Collection<BasicBlock> getBasicBlocks() {
return graph.allData();
}