research-article

How to compute worst-case execution time by optimization modulo theory and a clever encoding of program semantics

Authors:

Mihail Asavoae,

David Monniaux,

Claire MaïzaAuthors Info & Claims

ACM SIGPLAN Notices, Volume 49, Issue 5

Pages 43 - 52

https://doi.org/10.1145/2666357.2597817

Published: 12 June 2014 Publication History

Abstract

In systems with hard real-time constraints, it is necessary to compute upper bounds on the worst-case execution time (WCET) of programs; the closer the bound to the real WCET, the better. This is especially the case of synchronous reactive control loops with a fixed clock; the WCET of the loop body must not exceed the clock period.

We compute the WCET (or at least a close upper bound thereof) as the solution of an optimization modulo theory problem that takes into account the semantics of the program, in contrast to other methods that compute the longest path whether or not it is feasible according to these semantics. Optimization modulo theory extends satisfiability modulo theory (SMT) to maximization problems.

Immediate encodings of WCET problems into SMT yield formulas intractable for all current production-grade solvers --- this is inherent to the DPLL(T) approach to SMT implemented in these solvers. By conjoining some appropriate "cuts" to these formulas, we considerably reduce the computation time of the SMT-solver.

We experimented our approach on a variety of control programs, using the OTAWA analyzer both as baseline and as underlying microarchitectural analysis for our analysis, and show notable improvement on the WCET bound on a variety of benchmarks and control programs.

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How to compute worst-case execution time by optimization modulo theory and a clever encoding of program semantics

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Information

Published In

cover image ACM SIGPLAN Notices

ACM SIGPLAN Notices Volume 49, Issue 5

LCTES '14

May 2014

162 pages

ISSN:0362-1340

EISSN:1558-1160

DOI:10.1145/2666357

Editors:
Mark W. Bailey
Hamilton College, Clinton, NY
,
Rajeev Balasubramonian
University of Utah
,
Al Davis
University of Utah
,
Sarita Adve
University of Illinois at Urbana-Champ

Issue’s Table of Contents

LCTES '14: Proceedings of the 2014 SIGPLAN/SIGBED conference on Languages, compilers and tools for embedded systems
June 2014
174 pages
ISBN:9781450328777
DOI:10.1145/2597809
General Chair:
Youtao Zhang
University of Pittsburgh, USA
,
Program Chair:
Prasad Kulkarni
University of Kansas, USA

Copyright © 2014 ACM.

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Association for Computing Machinery

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Published: 12 June 2014

Published in SIGPLAN Volume 49, Issue 5

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Cited By

Yao PShi QHuang HZhang C(2021)Program analysis via efficient symbolic abstractionProceedings of the ACM on Programming Languages10.1145/34854955:OOPSLA(1-32)Online publication date: 20-Oct-2021
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Peter SGivargis T(2021)Generation and Verification of Timing Attack Resilient Schedules During the High-Level Synthesis of Integrated CircuitsBehavioral Synthesis for Hardware Security10.1007/978-3-030-78841-4_15(343-363)Online publication date: 28-May-2021
https://doi.org/10.1007/978-3-030-78841-4_15
Sebastiani RTrentin P(2018)OptiMathSAT: A Tool for Optimization Modulo TheoriesJournal of Automated Reasoning10.1007/s10817-018-09508-6Online publication date: 15-Dec-2018
https://doi.org/10.1007/s10817-018-09508-6
Becker MMetta RVenkatesh RChakraborty S(2018)Scalable and precise estimation and debugging of the worst-case execution time for analysis-friendly processors: a comeback of model checkingInternational Journal on Software Tools for Technology Transfer10.1007/s10009-018-0497-2Online publication date: 11-Jun-2018
https://doi.org/10.1007/s10009-018-0497-2
Meng FSu X(2017)Reducing WCET Overestimations by Correcting Errors in Loop Bound ConstraintsEnergies10.3390/en1012211310:12(2113)Online publication date: 12-Dec-2017
https://doi.org/10.3390/en10122113
Krafczyk NRiener HFey G(2016)WCET overapproximation for software in the context of a Cyber-Physical System2016 IFIP/IEEE International Conference on Very Large Scale Integration (VLSI-SoC)10.1109/VLSI-SoC.2016.7753559(1-6)Online publication date: Sep-2016
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Meng FSu XQu Z(2016)Nonlinear approach for estimating WCET during programming phaseCluster Computing10.1007/s10586-016-0606-519:3(1449-1459)Online publication date: 1-Sep-2016
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Sebastiani RTrentin P(2015)OptiMathSAT: A Tool for Optimization Modulo TheoriesComputer Aided Verification10.1007/978-3-319-21690-4_27(447-454)Online publication date: 16-Jul-2015
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Tsiskaridze NBarrett CTinelli C(2024)Generalized Optimization Modulo TheoriesAutomated Reasoning10.1007/978-3-031-63498-7_27(458-479)Online publication date: 1-Jul-2024
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