Making Bubbling Practical

Sergio Antoy; Steven Libby

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arXiv · 1808.07990

Making Bubbling Practical

Sergio Antoy·Steven Libby

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Abstract

Bubbling is a run-time graph transformation studied for the execution of non-deterministic steps in functional logic computations. This transformation has been proven correct, but as currently formulated it requires information about the entire context of a step, even when the step affects only a handful of nodes. Therefore, despite some advantages, it does not appear to be competitive with approaches that require only localized information, such as backtracking and pull-tabbing. We propose a novel algorithm that executes bubbling steps accessing only local information. To this aim, we define graphs that have an additional attribute, a dominator of each node, and we maintain this attribute when a rewrite and/or bubbling step is executed. When a bubbling step is executed, the dominator is available at no cost, and only local information is accessed. Our work makes bubbling practical, and theoretically competitive, for implementing non-determinism in functional logic computations.

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Sergio Antoy, Steven Libby. 2018-08-24. Making Bubbling Practical. https://arxiv.org/abs/1808.07990

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