Published 2019-02-18
Keywords
- Worst Case Execution Time estimation,
- Infeasible Execution Paths,
- Abstract Interpretation
Copyright (c) 2018 Pascal Raymond, Claire Maiza, Catherine Parent-Vigouroux, Erwan Jahier, Nicolas Halbwachs, Fabienne Carrier, Mihail Asavoae, and Rémy Boutonnet

This work is licensed under a Creative Commons Attribution 3.0 Unported License.
How to Cite
[1]
2019. Improving WCET Evaluation using Linear Relation Analysis. Leibniz Transactions on Embedded Systems. 6, 1 (Feb. 2019), 02:1–02:28. DOI:https://doi.org/10.4230/LITES-v006-i001-a002.
Abstract
The precision of a worst case execution time (WCET) evaluation tool on a given program is highly dependent on how the tool is able to detect and discard semantically infeasible executions of the program. In this paper, we propose to use the classical abstract interpretation-based method of linear relation analysis to discover and exploit relations between execution paths. For this purpose, we add auxiliary variables (counters) to the program to trace its execution paths. The results are easily incorporated in the classical workflow of a WCET evaluator, when the evaluator is based on the popular implicit path enumeration technique. We use existing tools - a WCET evaluator and a linear relation analyzer - to build and experiment a prototype implementation of this idea.References
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