
An Algebraic Approach to Sharing Analysis of Logic ProgramsMichael Codish, Vitaly Lagoon and Francesco Bueno
The Journal of Logic Programming;
41 (2): 110149,
2000
Abstract:This paper describes an algebraic approach to the sharing analysis of logic programs based on an abstract domain of set logic programs. Set logic programs are logic programs in which the terms are sets of variables and unification is based on an associative, commutative, and idempotent equality theory. All of the basic operations required for sharing analyses, as well as their formal justification, are based on simple algebraic properties of set substitutions and setbased atoms. An ordering on setbased syntactic objects, similar to ``less general' on concrete syntactic objects, is shown to reflect the notion of ``less sharing' information. The (abstract) unification of a pair of setbased terms corresponds to finding their most general ACI1 unifier with respect to this ordering. The unification of a set of equations between setbased terms is defined exactly as in the concrete case, by solving the equations one by one and repeatedly applying their solutions to the remaining equations. We demonstrate that all of the operations in a sharing analysis have natural definitions which are both correct and optimal.Available: bibtex entry compressed postscript Related sites: The conference version PDF from the publisher PDF from Scirus  scientific search engine Michael Codish The Department of Computer Science BenGurion University of the Negev PoB 653, BeerSheva, 84105, Israel mcodish@cs.bgu.ac.il
