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On the Complexity of Constant Propagation

  • Markus Müller-Olm
  • Oliver Rüthing
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2028)

Abstract

Constant propagation (CP) is one of the most widely used optimizations in practice (cf. [9]). Intuitively, it addresses the problem of statically detecting whether an expression always evaluates to a unique constant at run-time. Unfortunately, as proved by different authors [4, 16], CP is in general undecidable even if the interpretation of branches is completely ignored. On the other hand, it is certainly decidable in more restricted settings, like on loop-free programs (cf. [7]. In this paper, we explore the complexity of CP for a three-dimensional taxonomy. We present an almost complete complexity classification, leaving only two upper bounds open.

Keywords

Constant Propagation Start Node Program Point Conditional Branch Polynomial Time Reduction 
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.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Markus Müller-Olm
    • 1
  • Oliver Rüthing
    • 1
  1. 1.FB InformatikUniversität DortmundDortmundGermany

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