Design and Implementation of a Modern ASP Grounder

This thesis focuses on the ex-novo design and implementation of a new modern and efficient ASP instantiator. To this end, we study a series of techniques geared towards the optimization of the grounding process, questioning the techniques employed by modern grounders with the aim of improving them and introducing further optimization strategies, which lend themselves to the integration into a generic grounder module of a traditional ASP system following a ground & solve approach. In particular, we herein present the novel system I-DLV that incorporates all these techniques leveraging on their synergy to perform an efficient instantiation. The system features full support to ASP-Core-2 standard language, advanced flexibility and customizability mechanisms, and is endowed with extensible design that eases the incorporation of language updates and optimization techniques. Moreover, its usage is twofold: besides being a stand-alone grounder, it is also a full-fledged deductive database engine. In addition, along with the solver WASP it has been integrated in the new version of the widespread ASP system DLV recently released.