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arXiv · 1104.1729

Expression Templates Revisited: A Performance Analysis of the Current ET Methodology

Klaus Iglberger·Georg Hager·Jan Treibig·Ulrich Ruede
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Abstract

In the last decade, Expression Templates (ET) have gained a reputation as an efficient performance optimization tool for C++ codes. This reputation builds on several ET-based linear algebra frameworks focused on combining both elegant and high-performance C++ code. However, on closer examination the assumption that ETs are a performance optimization technique cannot be maintained. In this paper we demonstrate and explain the inability of current ET-based frameworks to deliver high performance for dense and sparse linear algebra operations, and introduce a new "smart" ET implementation that truly allows the combination of high performance code with the elegance and maintainability of a domain-specific language.

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Klaus Iglberger, Georg Hager, Jan Treibig, Ulrich Ruede. 2011-04-09. Expression Templates Revisited: A Performance Analysis of the Current ET Methodology. https://doi.org/10.1137/110830125

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