Write a source sink analyzer

Writing a source-sink analyzer become fairly easy on top of our interprocedure sparse value-flow graph (you may wish to refer to LeakCheck.cpp to see the detail code implementations).

1. First, we need to build SVFG using andersen's pointer analysis

PointerAnalysis* ander = AndersenWaveDiff::createAndersenWaveDiff(module);
svfg = new SVFGOPT(ptaCallGraph);
svfgbuilder.build(svfg,ander);

2. Choose a set of candidate sources and sinks

Simple code to iterate from a SVFGNode on SVFG
for(SVFGNode::const_iterator it = node->OutEdgeBegin(), eit = node->OutEdgeEnd(); it!=eit; ++it) {
}

3. Perform all path reachable analysis using AllPathReachableSolve method (ProgSlice class) which computes value-flow guards via the following three methods iteratively util a fixed point is reached.

• ComputeInterCallVFGGuard
• ComputeInterRetVFGGuard
• ComputeIntraVFGGuard