Roberto, Margherita and Beatrice


Personal Info




Enhancing Sharing for Precision

Roberto Bagnara
Dipartimento di Matematica e Informatica
Università di Parma
Parco Area delle Scienze 53/A
I-43124 Parma

Enea Zaffanella
Servizio IX Automazione
Università di Modena

Patricia M. Hill
School of Computer Studies
University of Leeds
Leeds, LS2 9JT
United Kingdom


Regarding the precision of combined domains including Jacobs and Langen's Sharing there is a core of techniques, such as the standard integration with freeness and linearity information, that are widely used and well accepted. However, a number of other proposals for refined domain combinations have been circulating more or less clandestinely for years. One feature that is common to these proposals is that they do not seem to have undergone experimental evaluation. We question whether significantly more precision is obtainable thanks to these techniques. In particular, we discuss and/or experimentally evaluate: helping Sharing with definitely ground variables computed with Pos; the incorporation of explicit structural information into the domain of analysis; more sophisticated ways of integrating Sharing and Pos; the issue of reordering the bindings in the computation of the abstract mgu; an original proposal concerning the addition of a domain recording the set of variables that are deemed to be ground or free; a more refined way of using linearity to improve the analysis; the issue of whether tracking compoundness allows to compute more precise sharing information; and, finally, the recovery of hidden information in the combination of Sharing with the usual domain for freeness.

Keywords: Mode Analysis, Sharing Analysis, Abstract Interpretation.

Available: PDF, 300 DPI, 600 DPI, and 1200 DPI PostScript, DVI, BibTeX entry.

[Page last updated on January 22, 2000, 20:38:36.]

© Roberto Bagnara

Home | Personal | Papers | Teaching | Links