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WCET-Aware Source Code Level Optimizations

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Worst-Case Execution Time Aware Compilation Techniques for Real-Time Systems

Part of the book series: Embedded Systems ((EMSY))

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Abstract

High-performance embedded systems can only be developed when efficiency requirements are pursued at different levels of the system design. A predominant role is associated with compilers which are responsible for the generation of efficient machine code. To accomplish this goal, compilers have to feature advanced optimizations. The class of source code optimizations provides a number of benefits compared to optimizations applied at lower abstraction levels of the code. The most important issues are portability, early application in the optimization sequence to enable subsequent optimizations, and availability of more details about the program structure due to the high level of abstraction. In this chapter, novel WCET-aware source code level optimizations are presented, including procedure cloning, superblock optimizations, loop unrolling, and loop unswitching. Moreover, a technique called invariant path is presented to accelerate WCET-aware optimizations.

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Authors and Affiliations

  1. Suitbertusstr. 34, 40223, Düsseldorf, Germany

    Paul Lokuciejewski

  2. Embedded Systems Group, TU Dortmund University, Otto-Hahn-Str. 16, 44221, Dortmund, Germany

    Peter Marwedel

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  1. Paul Lokuciejewski
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  2. Peter Marwedel
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Correspondence to Paul Lokuciejewski .

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Lokuciejewski, P., Marwedel, P. (2011). WCET-Aware Source Code Level Optimizations. In: Worst-Case Execution Time Aware Compilation Techniques for Real-Time Systems. Embedded Systems. Springer, Dordrecht. https://doi.org/10.1007/978-90-481-9929-7_4

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  • DOI: https://doi.org/10.1007/978-90-481-9929-7_4

  • Publisher Name: Springer, Dordrecht

  • Print ISBN: 978-90-481-9928-0

  • Online ISBN: 978-90-481-9929-7

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