Probabilistic Program Verification via Inductive Synthesis of Inductive Invariants

A desired property of randomized systems, represented by probabilistic programs, is that the probability to reach some error state is sufficiently small; verification of such properties is often addressed by probabilistic model checking. We contribute an inductive synthesis approach for proving quantitative reachability properties by finding inductive invariants on source-code level. Our prototype implementation of various flavors of this approach shows promise: it finds inductive invariants for (in)finite-state programs, while beating state-of-the-art model checkers on some benchmarks and often outperforming monolithic alternatives.