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arXiv · 1208.4549

Forward Analysis for WSTS, Part II: Complete WSTS

Alain Finkel·Jean Goubault-Larrecq
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Abstract

We describe a simple, conceptual forward analysis procedure for infinity-complete WSTS S. This computes the so-called clover of a state. When S is the completion of a WSTS X, the clover in S is a finite description of the downward closure of the reachability set. We show that such completions are infinity-complete exactly when X is an omega-2-WSTS, a new robust class of WSTS. We show that our procedure terminates in more cases than the generalized Karp-Miller procedure on extensions of Petri nets and on lossy channel systems. We characterize the WSTS where our procedure terminates as those that are clover-flattable. Finally, we apply this to well-structured counter systems.

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Alain Finkel, Jean Goubault-Larrecq. 2012-08-22. Forward Analysis for WSTS, Part II: Complete WSTS. https://doi.org/10.2168/lmcs-8(3:28)2012

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