The GRAT Tool Chain

Efficient (UN)SAT Certificate Checking with Formal Correctness Guarantees
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10491)


We present the GRAT tool chain, which provides an efficient and formally verified SAT and UNSAT certificate checker. It utilizes a two phase approach: The highly optimized gratgen tool converts a DRAT certificate to a GRAT certificate, which is then checked by the formally verified gratchk tool.

On a realistic benchmark suite drawn from the 2016 SAT competition, our approach is faster than the unverified standard tool drat-trim, and significantly faster than the formally verified LRAT tool. An optional multithreaded mode allows for even faster checking of a single certificate.



We thank Simon Wimmer for proofreading, and the anonymous reviewers for their useful comments.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Technische Universität MünchenMunichGermany

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