Abstract
Syntactic unification has widespread use in computing. There are several operations used in deductive computing such as critical pair generation, paramodulation and narrowing that require unifying a term s with every subterm of another term p. This subterm unification problem can be solved naively by repeatedly unifying s with each subterm of p in isolation. The drawback of doing unification in isolation is that commonality among subterms of p is ignored. We present an algorithm for efficient subterm unification by exploiting this commonality. The central idea used in our algorithm is to reduce the common part computation in unification into a string-matching problem and solve it efficiently using a string-matching automaton. The automaton succinctly captures the commonality between subterms of p. The string-matching approach, in conjunction with two new techniques called bidirectional-reduce and marking enables efficient unification of s with every subterm of p.
Research supported by NSP grant CCR-9110055.
Research supported by NSF grants CCR-9102159, 9404921, CDA-9303181 and INT-9314412.
Research done while at SUNY, Stony Brook.
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© 1994 Springer-Verlag Berlin Heidelberg
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Ramesh, R., Ramakrishnan, I.V., Sekar, R.C. (1994). Automata-driven efficient subterm unification. In: Thiagarajan, P.S. (eds) Foundation of Software Technology and Theoretical Computer Science. FSTTCS 1994. Lecture Notes in Computer Science, vol 880. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-58715-2_132
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DOI: https://doi.org/10.1007/3-540-58715-2_132
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