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arXiv · 1805.07490

Productively Expressing High-performance Spatial Designs of Givens Rotation-based QR Decomposition Algorithm

Hongbo Rong
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Abstract

QR decomposition is used prevalently in wireless communication. In this paper, we express the Givens-rotation-based QR decomposition algorithm on a spatial architecture using T2S (Temporal To Spatial), a high-productivity spatial programming methodology for expressing high-performance spatial designs. There are interesting challenges: the loop iteration space is not rectangular, and it is not obvious how the imperative algorithm can be expressed in a functional notation, the starting point of T2S. Using QR decomposition as an example, this paper elucidates some general principle, and de-mystifies high-performance spatial programming. The paper also serves as a tutorial of spatial programming for programmers who are not mathematicians, not expert programmers, and not experts on spatial architectures, but still hope to intuitively identify a high-performance design and map to spatial architectures efficiently.

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Hongbo Rong. 2018-05-19. Productively Expressing High-performance Spatial Designs of Givens Rotation-based QR Decomposition Algorithm. https://arxiv.org/abs/1805.07490

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