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arXiv · 1207.3262

Canonized Rewriting and Ground AC Completion Modulo Shostak Theories : Design and Implementation

Sylvain Conchon·Evelyne Contejean·Mohamed Iguernelala
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Abstract

AC-completion efficiently handles equality modulo associative and commutative function symbols. When the input is ground, the procedure terminates and provides a decision algorithm for the word problem. In this paper, we present a modular extension of ground AC-completion for deciding formulas in the combination of the theory of equality with user-defined AC symbols, uninterpreted symbols and an arbitrary signature disjoint Shostak theory X. Our algorithm, called AC(X), is obtained by augmenting in a modular way ground AC-completion with the canonizer and solver present for the theory X. This integration rests on canonized rewriting, a new relation reminiscent to normalized rewriting, which integrates canonizers in rewriting steps. AC(X) is proved sound, complete and terminating, and is implemented to extend the core of the Alt-Ergo theorem prover.

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Sylvain Conchon, Evelyne Contejean, Mohamed Iguernelala. 2012-07-13. Canonized Rewriting and Ground AC Completion Modulo Shostak Theories : Design and Implementation. https://doi.org/10.2168/lmcs-8(3:16)2012

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