QBO: a query tool specially developed to explore programs

We introduce QBO, or Query by Outlines, a tool specially developed to help explore programs. It relies on a previously implemented system able to automatically construct outlines (F. Balmas, 1997; 1998): every linear loop identified in a program is conceptualized according to the kind of computations it performs. QBO proposes an outline storage mechanism together with a query algorithm that enables outlines to be efficiently retrieved. QBO eases exploration of programs, thus program management, clone detection or plan recognition can be envisaged at lower cost; as outlines are already computed and indexed, only high level constructs have to be checked. Therefore, answering queries is a rather fast process. We sketch our outlining model, present our query tool and discuss how query by outlines may help explore programs