Reducing the Functionality Gap Between Auto-Vectorization and Explicit Vectorization

Compress/Expand and Histogram
  • Hideki SaitoEmail author
  • Serge Preis
  • Nikolay Panchenko
  • Xinmin Tian
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9903)


Explicit vectorization of C/C++ and FORTRAN application programs are pioneered by Intel® Cilk™ Plus and then inherited and enhanced by OpenMP 4.0 and 4.5 standardization. There is a known functionality gap, where some auto-vectorizable code does not have adequate syntax support for explicit vector programming. In this paper, we propose and discuss a few syntax extensions to reduce the gap for compress/expand and histogram idioms, which are commonly seen in high performance computing.


Compress Expand Histogram OpenMP omp ordered simd 


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Hideki Saito
    • 1
    Email author
  • Serge Preis
    • 1
  • Nikolay Panchenko
    • 1
  • Xinmin Tian
    • 1
  1. 1.Software and Solutions GroupIntel CorporationSanta ClaraUSA

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