protected Set<D> computeReturnFlowFunction(FlowFunction<D> retFunction,D d1,D d2,N callSite,Collection<D> callerSideDs){
  return retFunction.computeTargets(d2);
}

protected Set < D > computeReturnFlowFunction ( FlowFunction < D > retFunction , D d1 , D d2 , N callSite , Collection < D > callerSideDs ) { return retFunction . computeTargets ( d2 ) ; }
computes the return flow function for the given set of caller - side abstractions .
