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A Loop Transformation Using Two Parallel Region Partitioning Method

  • Sam Jin Jeong
  • Jung Soo Han
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3756)

Abstract

Loop parallelization is an important optimization issue in the execution of scientific programs. This paper proposes loop transformation techniques for finding parallel regions within nested loops with non-uniform dependences in order to improve parallelism. By parallelizing anti dependence region using variable renaming, there remains only flow dependence in the loop. We then divide the iteration space into FDT (Flow Dependence Tail set) and FDH (Flow Dependence Head set). By two given equations, we show how to determine whether the intersection of FDT and FDH is empty or not. So, we can find two parallel regions for doubly nested loops with non-uniform dependences. In the case that FDT does not overlap FDH, we will divide the iteration space into two parallel regions by a line.

Keywords

Iteration Space Nest Loop Parallel Region Flow Dependence Loop Transformation 
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 2005

Authors and Affiliations

  • Sam Jin Jeong
    • 1
  • Jung Soo Han
    • 1
  1. 1.Division of Information and Communication EngineeringCheonan UniversityCheonan CityKorea

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