goSLP: globally optimized superword level parallelism framework

<jats:p>Modern microprocessors are equipped with single instruction multiple data (SIMD) or vector instruction sets which allow compilers to exploit superword level parallelism (SLP), a type of fine-grained parallelism. Current SLP auto-vectorization techniques use heuristics to discover vecto...

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Main Authors: Mendis, Charith, Amarasinghe, Saman
Other Authors: Sloan School of Management
Format: Article
Language:English
Published: Association for Computing Machinery (ACM) 2021
Online Access:https://hdl.handle.net/1721.1/135078
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author Mendis, Charith
Amarasinghe, Saman
author2 Sloan School of Management
author_facet Sloan School of Management
Mendis, Charith
Amarasinghe, Saman
author_sort Mendis, Charith
collection MIT
description <jats:p>Modern microprocessors are equipped with single instruction multiple data (SIMD) or vector instruction sets which allow compilers to exploit superword level parallelism (SLP), a type of fine-grained parallelism. Current SLP auto-vectorization techniques use heuristics to discover vectorization opportunities in high-level language code. These heuristics are fragile, local and typically only present one vectorization strategy that is either accepted or rejected by a cost model. We present goSLP, a novel SLP auto-vectorization framework which solves the statement packing problem in a pairwise optimal manner. Using an integer linear programming (ILP) solver, goSLP searches the entire space of statement packing opportunities for a whole function at a time, while limiting total compilation time to a few minutes. Furthermore, goSLP optimally solves the vector permutation selection problem using dynamic programming. We implemented goSLP in the LLVM compiler infrastructure, achieving a geometric mean speedup of 7.58% on SPEC2017fp, 2.42% on SPEC2006fp and 4.07% on NAS benchmarks compared to LLVM’s existing SLP auto-vectorizer.</jats:p>
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spelling mit-1721.1/1350782024-01-02T19:17:53Z goSLP: globally optimized superword level parallelism framework Mendis, Charith Amarasinghe, Saman Sloan School of Management <jats:p>Modern microprocessors are equipped with single instruction multiple data (SIMD) or vector instruction sets which allow compilers to exploit superword level parallelism (SLP), a type of fine-grained parallelism. Current SLP auto-vectorization techniques use heuristics to discover vectorization opportunities in high-level language code. These heuristics are fragile, local and typically only present one vectorization strategy that is either accepted or rejected by a cost model. We present goSLP, a novel SLP auto-vectorization framework which solves the statement packing problem in a pairwise optimal manner. Using an integer linear programming (ILP) solver, goSLP searches the entire space of statement packing opportunities for a whole function at a time, while limiting total compilation time to a few minutes. Furthermore, goSLP optimally solves the vector permutation selection problem using dynamic programming. We implemented goSLP in the LLVM compiler infrastructure, achieving a geometric mean speedup of 7.58% on SPEC2017fp, 2.42% on SPEC2006fp and 4.07% on NAS benchmarks compared to LLVM’s existing SLP auto-vectorizer.</jats:p> 2021-10-27T20:10:37Z 2021-10-27T20:10:37Z 2018 2019-05-03T18:23:30Z Article http://purl.org/eprint/type/ConferencePaper https://hdl.handle.net/1721.1/135078 en 10.1145/3276480 Proceedings of the ACM on Programming Languages Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf Association for Computing Machinery (ACM) ACM
spellingShingle Mendis, Charith
Amarasinghe, Saman
goSLP: globally optimized superword level parallelism framework
title goSLP: globally optimized superword level parallelism framework
title_full goSLP: globally optimized superword level parallelism framework
title_fullStr goSLP: globally optimized superword level parallelism framework
title_full_unstemmed goSLP: globally optimized superword level parallelism framework
title_short goSLP: globally optimized superword level parallelism framework
title_sort goslp globally optimized superword level parallelism framework
url https://hdl.handle.net/1721.1/135078
work_keys_str_mv AT mendischarith goslpgloballyoptimizedsuperwordlevelparallelismframework
AT amarasinghesaman goslpgloballyoptimizedsuperwordlevelparallelismframework