Refinement of Parallel Algorithms down to LLVM

Author Peter Lammich

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Peter Lammich
  • University of Twente, Enschede, The Netherlands

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Peter Lammich. Refinement of Parallel Algorithms down to LLVM. In 13th International Conference on Interactive Theorem Proving (ITP 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 237, pp. 24:1-24:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


We present a stepwise refinement approach to develop verified parallel algorithms, down to efficient LLVM code. The resulting algorithms' performance is competitive with their counterparts implemented in C/C++. Our approach is backwards compatible with the Isabelle Refinement Framework, such that existing sequential formalizations can easily be adapted or re-used. As case study, we verify a parallel quicksort algorithm, and show that it performs on par with its C++ implementation, and is competitive to state-of-the-art parallel sorting algorithms.

Subject Classification

ACM Subject Classification
  • Software and its engineering → Formal software verification
  • Theory of computation → Semantics and reasoning
  • Computing methodologies → Parallel algorithms
  • Isabelle
  • Concurrent Separation Logic
  • Parallel Sorting
  • LLVM


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