Toward Compact Abstractions for Processor Pipelines

  • Sebastian Hahn
  • Jan Reineke
  • Reinhard Wilhelm
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9360)


Hard real-time systems require programs to react on time. Static timing analysis derives timing guarantees by analyzing the behavior of programs running on the underlying execution platform. Efficient abstractions have been found for the analysis of caches. Unfortunately, this is not the case for the analysis of processor pipelines. Pipeline analysis typically uses an expensive powerset domain of concrete pipeline states. Therefore, pipeline analysis is the most complex part of timing analysis. We propose a compact abstract domain for pipeline analysis. This pipeline analysis determines the minimal progress of instructions in the program through the pipeline.

We give a concrete semantics for an in-order pipeline, which forms the basis for an abstract semantics. On the way, we found out that in-order pipelines are not guaranteed to be free of timing anomalies, i.e. local worst decisions do not lead to the global worst case. We prove this by giving an example. A major problem is how to find an abstract semantics that guarantees progress on the abstract side. It turns out that monotonicity on the partial progress order is sufficient to guarantee this.


Pipeline Analysis Pipeline Stage Instruction Sequence Abstract Domain Abstract Semantic 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Cousot, P., Cousot, R.: Systematic design of program analysis frameworks. In: Aho, A.V., Zilles, S.N., Rosen, B.K. (eds.) Conference Record of the Sixth Annual ACM Symposium on Principles of Programming Languages, pp. 269–282. ACM Press (1979)Google Scholar
  2. 2.
    Ferdinand, C., Wilhelm, R.: Efficient and precise cache behavior prediction for real-time systems. Real-Time Systems 17(2–3), 131–181 (1999)CrossRefGoogle Scholar
  3. 3.
    Gebhard, G.: Timing anomalies reloaded. In: Lisper, B. (ed.) 10th International Workshop on Worst-Case Execution Time Analysis, WCET. OASICS, vol. 15, pp. 1–10. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, Germany (2010)Google Scholar
  4. 4.
    Langenbach, M., Thesing, S., Heckmann, R.: Pipeline modeling for timing analysis. In: Hermenegildo, M.V., Puebla, G. (eds.) SAS 2002. LNCS, vol. 2477, pp. 294–309. Springer, Heidelberg (2002) CrossRefGoogle Scholar
  5. 5.
    Liu, I., Reineke, J., Lee, E.A.: A PRET architecture supporting concurrent programs with composable timing properties. In: Conference Record of the Forty Fourth Asilomar Conference on Signals, Systems and Computers, pp. 2111–2115. IEEE (2010)Google Scholar
  6. 6.
    Reineke, J., Wachter, B., Thesing, S., Wilhelm, R., Polian, I., Eisinger, J., Becker, B.: A definition and classification of timing anomalies. In: Mueller, F. (ed.) 6th Intl. Workshop on Worst-Case Execution Time (WCET) Analysis. OASICS, vol. 4. Internationales Begegnungs- und Forschungszentrum fuer Informatik (IBFI), Schloss Dagstuhl, Germany (2006) Google Scholar
  7. 7.
    Rochange, C., Sainrat, P.: A time-predictable execution mode for superscalar pipelines with instruction prescheduling. In: Bagherzadeh, N., Valero, M., Ramírez, A. (eds.) Proceedings of the Second Conference on Computing Frontiers, pp. 307–314. ACM (2005)Google Scholar
  8. 8.
    Sagiv, M., Reps, T., Wilhelm, R.: Parametric shape analysis via 3-valued logic. In: Proceedings of the 26th ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages. POPL 1999, pp. 105–118. ACM, New York (1999)Google Scholar
  9. 9.
    Thesing, S.: Safe and precise WCET determination by abstract interpretation of pipeline models. Ph.D. thesis, Saarland University (2005)Google Scholar
  10. 10.
    Wenzel, I., Kirner, R., Puschner, P., Rieder, B.: Principles of timing anomalies in superscalar processors. In: Fifth International Conference on Quality Software (QSIC 2005). IEEE (2005)Google Scholar
  11. 11.
    Wilhelm, S.: Efficient analysis of pipeline models for WCET computation. In: Wilhelm, R. (ed.) 5th Intl. Workshop on Worst-Case Execution Time (WCET) Analysis. OASICS, vol. 1. Internationales Begegnungs- und Forschungszentrum für Informatik (IBFI), Schloss Dagstuhl, Germany (2005) Google Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Sebastian Hahn
    • 1
  • Jan Reineke
    • 1
  • Reinhard Wilhelm
    • 1
    • 2
  1. 1.InformatikSaarland UniversitySaarbrückenGermany
  2. 2.AbsInt Angewandte Informatik GmbHSaarbrückenGermany

Personalised recommendations