Segment Abstraction for Worst-Case Execution Time Analysis

  • Pavol Černý
  • Thomas A. Henzinger
  • Laura Kovács
  • Arjun Radhakrishna
  • Jakob Zwirchmayr
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9032)

Abstract

In the standard framework for worst-case execution time (WCET) analysis of programs, the main data structure is a single instance of integer linear programming (ILP) that represents the whole program. The instance of this NP-hard problem must be solved to find an estimate for WCET, and it must be refined if the estimate is not tight. We propose a new framework for WCET analysis, based on abstract segment trees (ASTs) as the main data structure. The ASTs have two advantages. First, they allow computing WCET by solving a number of independent small ILP instances. Second, ASTs store more expressive constraints, thus enabling a more efficient and precise refinement procedure. In order to realize our framework algorithmically, we develop an algorithm for WCET estimation on ASTs, and we develop an interpolation-based counterexample-guided refinement scheme for ASTs. Furthermore, we extend our framework to obtain parametric estimates of WCET. We experimentally evaluate our approach on a set of examples from WCET benchmark suites and linear-algebra packages. We show that our analysis, with comparable effort, provides WCET estimates that in many cases significantly improve those computed by existing tools.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Pavol Černý
    • 1
  • Thomas A. Henzinger
    • 2
  • Laura Kovács
    • 3
  • Arjun Radhakrishna
    • 4
  • Jakob Zwirchmayr
    • 5
  1. 1.University of ColoradoBoulderUSA
  2. 2.ISTKlosterneuburgAustria
  3. 3.Chalmers University of TechnologyGothenburgSweden
  4. 4.University of PennsylvaniaPhiladelphiaUSA
  5. 5.Institut de Recherche en Informatique de ToulouseToulouseFrance

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