/**
* collect the putstatic instructions in the call graph as {@link PathEdge} seeds for the
* analysis
*/
private Collection<PathEdge<BasicBlockInContext<IExplodedBasicBlock>>> collectInitialSeeds() {
Collection<PathEdge<BasicBlockInContext<IExplodedBasicBlock>>> result = HashSetFactory.make();
for (BasicBlockInContext<IExplodedBasicBlock> bb : supergraph) {
IExplodedBasicBlock ebb = bb.getDelegate();
SSAInstruction instruction = ebb.getInstruction();
if (instruction instanceof SSAPutInstruction) {
SSAPutInstruction putInstr = (SSAPutInstruction) instruction;
if (putInstr.isStatic()) {
final CGNode cgNode = bb.getNode();
Pair<CGNode, Integer> fact = Pair.make(cgNode, ebb.getFirstInstructionIndex());
int factNum = domain.add(fact);
BasicBlockInContext<IExplodedBasicBlock> fakeEntry = getFakeEntry(cgNode);
// note that the fact number used for the source of this path edge doesn't really matter
result.add(PathEdge.createPathEdge(fakeEntry, factNum, bb, factNum));
}
}
}
return result;
}
/** flow function for normal intraprocedural edges */
public IUnaryFlowFunction getNormalFlowFunction(
final BasicBlockInContext<IExplodedBasicBlock> src,
BasicBlockInContext<IExplodedBasicBlock> dest) {
final IExplodedBasicBlock ebb = src.getDelegate();
SSAInstruction instruction = ebb.getInstruction();
if (instruction instanceof SSAPutInstruction) {
final SSAPutInstruction putInstr = (SSAPutInstruction) instruction;
if (putInstr.isStatic()) {
return new IUnaryFlowFunction() {
public IntSet getTargets(int d1) {
// first, gen this statement
int factNum =
domain.getMappedIndex(Pair.make(src.getNode(), ebb.getFirstInstructionIndex()));
assert factNum != -1;
MutableSparseIntSet result = MutableSparseIntSet.makeEmpty();
result.add(factNum);
// if incoming statement is some different statement that defs the same static field,
// kill it; otherwise, keep it
if (d1 != factNum) {
IField staticField = cha.resolveField(putInstr.getDeclaredField());
assert staticField != null;
Pair<CGNode, Integer> otherPutInstrAndNode = domain.getMappedObject(d1);
SSAPutInstruction otherPutInstr =
(SSAPutInstruction)
otherPutInstrAndNode.fst.getIR()
.getInstructions()[otherPutInstrAndNode.snd];
IField otherStaticField = cha.resolveField(otherPutInstr.getDeclaredField());
if (!staticField.equals(otherStaticField)) {
result.add(d1);
}
}
return result;
}
public String toString() {
return "Reaching Defs Normal Flow";
}
};
}
}
// identity function when src block isn't for a putstatic
return IdentityFlowFunction.identity();
}
@Override
public boolean isExit(BasicBlockInContext<IExplodedBasicBlock> n) {
return n.getDelegate().isExitBlock();
}
@Override
public boolean isCall(BasicBlockInContext<IExplodedBasicBlock> n) {
return n.getDelegate().getInstruction() instanceof SSAAbstractInvokeInstruction;
}
@Override
public int getLocalBlockNumber(BasicBlockInContext<IExplodedBasicBlock> n) {
return n.getDelegate().getNumber();
}
/**
* we use the entry block of the CGNode as the fake entry when propagating from callee to caller
* with unbalanced parens
*/
public BasicBlockInContext<IExplodedBasicBlock> getFakeEntry(
BasicBlockInContext<IExplodedBasicBlock> node) {
final CGNode cgNode = node.getNode();
return getFakeEntry(cgNode);
}
