Whale: An Interpolation-Based Algorithm for Inter-procedural Verification

Aws Albarghouthi, Arie Gurfinkel, Marsha Chechik

Abstract: In software verification, Craig interpolation has proven to be a powerful technique for computing and refining abstractions. In this paper, we propose an interpolation-based software verification algorithm for checking safety properties of (possibly recursive) sequential programs. Our algorithm, called Whale, produces inter-procedural proofs of safety by exploiting interpolation for guessing function summaries by generalizing under-approximations (i.e., finite traces) of functions. We implemented our algorithm in LLVM and applied it to verifying properties of low-level code written for the pacemaker challenge. We show that our prototype implementation outperforms existing state-of-the-art tools.