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arXiv · 1905.11187

Proving Non-Termination via Loop Acceleration

Florian Frohn·Jürgen Giesl
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Abstract

We present the first approach to prove non-termination of integer programs that is based on loop acceleration. If our technique cannot show non-termination of a loop, it tries to accelerate it instead in order to find paths to other non-terminating loops automatically. The prerequisites for our novel loop acceleration technique generalize a simple yet effective non-termination criterion. Thus, we can use the same program transformations to facilitate both non-termination proving and loop acceleration. In particular, we present a novel invariant inference technique that is tailored to our approach. An extensive evaluation of our fully automated tool LoAT shows that it is competitive with the state of the art.

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Florian Frohn, Jürgen Giesl. 2019-05-27. Proving Non-Termination via Loop Acceleration. https://arxiv.org/abs/1905.11187

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