private void addPhiConstraints(
CGNode node, ControlFlowGraph<SSAInstruction, ISSABasicBlock> cfg, ISSABasicBlock b) {
// visit each phi instruction in each successor block
for (Iterator<? extends IBasicBlock> sbs = cfg.getSuccNodes(b); sbs.hasNext(); ) {
ISSABasicBlock sb = (ISSABasicBlock) sbs.next();
if (sb.isExitBlock()) {
// an optimization based on invariant that exit blocks should have no
// phis.
continue;
}
int n = 0;
// set n to be whichPred(this, sb);
for (Iterator<? extends IBasicBlock> back = cfg.getPredNodes(sb); back.hasNext(); n++) {
if (back.next() == b) {
break;
}
}
assert n < cfg.getPredNodeCount(sb);
for (Iterator<SSAPhiInstruction> phis = sb.iteratePhis(); phis.hasNext(); ) {
SSAPhiInstruction phi = phis.next();
if (phi == null) {
continue;
}
PointerKey def = heapModel.getPointerKeyForLocal(node, phi.getDef());
if (phi.getUse(n) > 0) {
PointerKey use = heapModel.getPointerKeyForLocal(node, phi.getUse(n));
addNode(def);
addNode(use);
addEdge(def, use);
}
// }
// }
}
}
}
/** Add constraints for a particular basic block. */
protected void addBlockInstructionConstraints(
CGNode node,
ControlFlowGraph<SSAInstruction, ISSABasicBlock> cfg,
ISSABasicBlock b,
StatementVisitor v) {
v.setBasicBlock(b);
// visit each instruction in the basic block.
for (Iterator<SSAInstruction> it = b.iterator(); it.hasNext(); ) {
SSAInstruction s = it.next();
if (s != null) {
s.visit(v);
}
}
addPhiConstraints(node, cfg, b);
}
@SuppressWarnings("unused")
private boolean loopsAreSimple(
ControlFlowGraph<SSAInstruction, ISSABasicBlock> cfg, Set<ISSABasicBlock> scc)
throws CancelException {
boolean isSimple = true;
MutableIntSet sccInts = MutableSparseIntSet.createMutableSparseIntSet(scc.size());
for (ISSABasicBlock bb : scc) {
sccInts.add(cfg.getNumber(bb));
}
boolean noExit = true;
for (ISSABasicBlock bb : scc) {
if (cfg.getSuccNodeCount(bb) > 1 && !cfg.getSuccNodeNumbers(bb).isSubset(sccInts)) {
noExit = false;
// if preds are no subset of the scc block we have a jump to the outside of the scc
SSAInstruction last = bb.getLastInstruction();
int[] uses = new int[last.getNumberOfUses()];
for (int i = 0; i < uses.length; i++) {
uses[i] = last.getUse(i);
}
TransitiveDataDependence tdep = new TransitiveDataDependence(scc);
tdep.solve(null);
for (ISSABasicBlock bb2 : scc) {
if (bb2 == bb) {
continue;
}
for (SSAInstruction ii : bb2) {
for (int use : uses) {
isSimple &= !tdep.influences(ii, use);
}
// IntSet is = tdep.influences((SSAInstruction) ii);
// System.err.println(ii + ": " + is);
if (!isSimple) {
break;
}
}
if (!isSimple) {
break;
}
}
// TODO check if condition is simple...
// if (isSimple) {
// System.err.println("Simple: " + last + " -> " +
// PrettyWalaNames.methodName(bb.getMethod()));
// } else {
// System.err.println("Not Simple: " + last + " -> " +
// PrettyWalaNames.methodName(bb.getMethod()));
// }
if (!isSimple) {
break;
}
}
}
return isSimple && !noExit;
}