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A Verified Generational Garbage Collector for CakeML

  • Adam Sandberg Ericsson
  • Magnus O. MyreenEmail author
  • Johannes Åman Pohjola
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10499)

Abstract

This paper presents the verification of a generational copying garbage collector for the CakeML runtime system. The proof is split into an algorithm proof and an implementation proof. The algorithm proof follows the structure of the informal intuition for the generational collector’s correctness, namely, a partial collection cycle in a generational collector is the same as running a full collection on part of the heap, if one views pointers to old data as non-pointers. We present a pragmatic way of dealing with ML-style mutable state, such as references and arrays, in the proofs. The development has been fully integrated into the in-logic bootstrapped CakeML compiler, which now includes command-line arguments that allow configuration of the generational collector. All proofs were carried out in the HOL4 theorem prover.

Notes

Acknowledgements

We thank Ramana Kumar for comments on drafts of this text. This work was partly supported by the Swedish Research Council and the Swedish Foundation for Strategic Research.

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Adam Sandberg Ericsson
    • 1
  • Magnus O. Myreen
    • 1
    Email author
  • Johannes Åman Pohjola
    • 1
  1. 1.Chalmers University of TechnologyGothenburgSweden

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