Making two-level static slicing in legacy systems

Slicing technique is considered as a valid help in many software engineering activities. Traditional slicing is made on programs, however, slicing all over legacy systems cannot be limited only to programs because part of the system logic is implemented at the JCL layer so we would distinguish two different slicing phases: slicing in-the-small at the program layer and slicing in-the-large at the JCL layer. In this work, the authors propose a two-level static slicing to provide a more effective approach to slice legacy systems. Both slicing in-the-small and slicing in-the-large is based on dependence graphs. Control and data dependencies are extended to model all code patterns. OSK tool implements the entire process.