Practical change impact analysis based on static program slicing for industrial software systems

Change impact analysis, i.e., knowing the potential consequences of a software change, is critical for the risk analysis, developer effort estimation, and regression testing of evolving software. Static program slicing is an attractive option for enabling routine change impact analysis for newly committed changesets during daily software build. For small programs with a few thousand lines of code, static program slicing scales well and can assist precise change impact analysis. However, as we demonstrate in this paper, static program slicing faces unique challenges when applied routinely on large and evolving industrial software systems. Despite recent advances in static program slicing, to our knowledge, there have been no studies of static change impact analysis applied on large and evolving industrial software systems. In this paper, we share our experiences in designing a static change impact analysis framework for such software systems. We have implemented our framework as a tool called Imp and have applied Imp on an industrial codebase with over a million lines of C/ C++ code with promising empirical results.