Control-Flow Refinement for Complexity Analysis of Probabilistic Programs in KoAT

Abstract

Recently, we showed how to use control-flow refinement (CFR) to improve automatic complexity analysis of integer programs. While up to now CFR was limited to classical programs, in this paper we extend CFR to probabilistic programs and show its soundness for complexity analysis. To demonstrate its benefits, we implemented our new CFR technique in our complexity analysis tool KoAT.