Efficient, Verified Checking of Propositional Proofs

  • Marijn Heule
  • Warren HuntJr.
  • Matt Kaufmann
  • Nathan Wetzler
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10499)

Abstract

Satisfiability (SAT) solvers—and software in general—sometimes have serious bugs. We mitigate these effects by validating the results. Today’s SAT solvers emit proofs that can be checked with reasonable efficiency. However, these checkers are not trivial and can have bugs as well. We propose to check proofs using a formally verified program that adds little overhead to the overall process of proof validation. We have implemented a sequence of increasingly efficient, verified checkers using the ACL2 theorem proving system, and we discuss lessons from this effort. This work is already being used in industry and is slated for use in the next SAT competition.

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Marijn Heule
    • 1
  • Warren HuntJr.
    • 1
  • Matt Kaufmann
    • 1
  • Nathan Wetzler
    • 2
  1. 1.The University of Texas at AustinAustinUSA
  2. 2.Intel CorporationHillsboroUSA

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