On Sharing, Memoization, and Polynomial Time (Long Version)

Martin Avanzini; Ugo Dal Lago

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arXiv · 1501.00894

On Sharing, Memoization, and Polynomial Time (Long Version)

Martin Avanzini·Ugo Dal Lago

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Abstract

We study how the adoption of an evaluation mechanism with sharing and memoization impacts the class of functions which can be computed in polynomial time. We first show how a natural cost model in which lookup for an already computed value has no cost is indeed invariant. As a corollary, we then prove that the most general notion of ramified recurrence is sound for polynomial time, this way settling an open problem in implicit computational complexity.

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Martin Avanzini, Ugo Dal Lago. 2015-01-05. On Sharing, Memoization, and Polynomial Time (Long Version). https://arxiv.org/abs/1501.00894

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