Supporting Queries on Source Code: a Formal Framework

Querying source code interactively for information is a critical task in reverse engineering of software. However, current source code query systems succeed in handling only small subsets of the wide range of queries possible on code, trading generality and expressive power for ease of implementation and practicality. We attribute this to the absence of clean formalisms for modeling and querying source code. In this paper, we present an algebraic framework (Source Code Algebra or SCA) that forms the basis of our source code query system. The bene ts of using SCA include the integration of structural and ow information into a single source code data model, the ability to process high-level source code queries (command-line, graphical, relational, or pattern-based) by expressing them as equivalent SCA expressions, the use of SCA itself as a powerful low-level source code query language, and opportunities for query optimization. We present the SCA's data model and operators and show that a variety of source code queries can be easily expressed using them. An algebraic model of source code addresses the issues of conceptual integrity, expressive power, and performance of a source code query system within a uni ed framework.