There and Back Again: A Netlist's Tale with Much Egraphin'

Gus Henry Smith; Zachary D. Sisco; Thanawat Techaumnuaiwit; Jingtao Xia; Vishal Canumalla; Andrew Cheung; Zachary Tatlock; Chandrakana Nandi; Jonathan Balkind

arXiv · 2404.00786

There and Back Again: A Netlist's Tale with Much Egraphin'

Gus Henry Smith·Zachary D. Sisco·Thanawat Techaumnuaiwit·Jingtao Xia·Vishal Canumalla·Andrew Cheung·Zachary Tatlock·Chandrakana Nandi·Jonathan Balkind

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Abstract

EDA toolchains are notoriously unpredictable, incomplete, and error-prone; the generally-accepted remedy has been to re-imagine EDA tasks as compilation problems. However, any compiler framework we apply must be prepared to handle the wide range of EDA tasks, including not only compilation tasks like technology mapping and optimization (the "there"} in our title), but also decompilation tasks like loop rerolling (the "back again"). In this paper, we advocate for equality saturation -- a term rewriting framework -- as the framework of choice when building hardware toolchains. Through a series of case studies, we show how the needs of EDA tasks line up conspicuously well with the features equality saturation provides.

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Gus Henry Smith, Zachary D. Sisco, Thanawat Techaumnuaiwit, Jingtao Xia, Vishal Canumalla, Andrew Cheung, Zachary Tatlock, Chandrakana Nandi, Jonathan Balkind. 2024-03-31. There and Back Again: A Netlist's Tale with Much Egraphin'. https://arxiv.org/abs/2404.00786

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