Section: New Results
Combining inference systems in the CDSAT framework
Participant : Stéphane Graham-Lengrand.
In 2016 we had designed a methodology [49], based on inference systems, for combining theories in SMT-solving, that supersedes the existing approaches, namely that of Nelson-Oppen [78] and that of MCSAT [86], [66]. While soundness and completeness of our approach were proved in 2016, we further developed, in 2017, the meta-theory of this system, now called CDSAT for Conflict-Driven Satisfiability, in particular with
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a proof of termination for the CDSAT system, and the identification of sufficient conditions, on the theory modules to be combined, for the global termination of the system to hold;
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a learning mechanism, whereby the system discovers lemmas along the run, which can be used later to speed-up the rest of the run;
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an enrichment of the CDSAT system with proof-object generation, and the identification of proof-construction primitives that can be used to make the answers produced by CDSAT correct-by-construction.
The first result, together with the introduction of the CDSAT framework, was publishing this year in [19]. The last two results are described in a paper accepted for publication at CPP in 2018.