Partial Redundancy Elimination using Lazy Code Motion

Sandeep Dasgupta; Tanmay Gangwani

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arXiv · 1905.08178

Partial Redundancy Elimination using Lazy Code Motion

Sandeep Dasgupta·Tanmay Gangwani

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Abstract

Partial Redundancy Elimination (PRE) is a compiler optimization that eliminates expressions that are redundant on some but not necessarily all paths through a program. In this project, we implemented a PRE optimization pass in LLVM and measured results on a variety of applications. We chose PRE because it is a powerful technique that subsumes Common Subexpression Elimination (CSE) and Loop Invariant Code Motion (LICM), and hence has the potential to greatly improve performance.

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Sandeep Dasgupta, Tanmay Gangwani. 2019-05-20. Partial Redundancy Elimination using Lazy Code Motion. https://arxiv.org/abs/1905.08178

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