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Verifying Relative Error Bounds Using Symbolic Simulation

  • Conference paper

Part of the Lecture Notes in Computer Science book series (LNTCS,volume 8559)

Abstract

In this paper we consider the problem of formally verifying hardware that is specified to compute reciprocal, reciprocal square root, and power-of-two functions on floating point numbers to within a given relative error. Such specifications differ from the common case in which any given input is specified to have exactly one correct output. Our approach is based on symbolic simulation with binary decision diagrams, and involves two distinct steps. First, we prove a lemma that reduces the relative error specification to several inequalities that involve reasoning about natural numbers only. The most complex of these inequalities asserts that the product of several naturals is less-than/greater-than another natural. Second, we invoke one of several customized algorithms that decides the inequality, without performing the expensive symbolic multiplications directly. We demonstrate the effectiveness of our approach on a next-generation Intel® processor design and report encouraging time and space metrics for these proofs.

Keywords

  • Relative Error
  • Boolean Function
  • Point Number
  • Binary Decision Diagram
  • Single Precision

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Bingham, J., Leslie-Hurd, J. (2014). Verifying Relative Error Bounds Using Symbolic Simulation. In: Biere, A., Bloem, R. (eds) Computer Aided Verification. CAV 2014. Lecture Notes in Computer Science, vol 8559. Springer, Cham. https://doi.org/10.1007/978-3-319-08867-9_18

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  • DOI: https://doi.org/10.1007/978-3-319-08867-9_18

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-319-08866-2

  • Online ISBN: 978-3-319-08867-9

  • eBook Packages: Computer ScienceComputer Science (R0)