A multi-level approach for visualization and exploration of reactive program behavior

This paper presents an approach for dynamic analysis and visualization of reactive program behavior. The objective is to understand the reactive behavior of complex programs for the purpose of finding unusual and possibly abnormal behavior, locating defects in the code, and finding causes of failures. Based on execution traces a multi-level analysis and visualization approach is proposed where, on one side, the behavior is analyzed to exhibit recurring execution patterns and their similarities and differences at a higher level of abstraction and, on the other side, program behavior can be explored in detail for giving explanations and showing causes of failures. The approach has been implemented as a tool chain for the analysis of PLC control programs. We discuss the key ideas of the approach, the implementation in a tool chain for PLC programs, and preliminary results from a case study.