Strategies for program inspection and visualization

• Main Author: Cruz, Daniela
• Publication Date: 2008
• Other Authors: Berón, Mario, Henriques, Pedro Rangel, Pereira, Maria João
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://hdl.handle.net/10198/922
• topic: Program comprehension; Program visualizer

The aim of this paper is to show the strategies involved in the implementation of two tools of PCVIA project that can be used for Program Comprehension. Both tools use known compiler techniques to inspect code in order to visualize and understand programs’ execution. On one hand we convert the source program into an internal decorated (or attributed) abstract syntax tree and then we visualize the structure traversing it, and applying visualization rules at each node according to a pre-defined rule-base. No changes are made in the source code, and the execution is simulated. On the other hand, we traverse the source program and instrument it with inspection functions. Those inspectors provide information about the function-call flow and data usage at runtime (during the actual program execution). This information is collected and gathered in an information repository that is then displayed in a suitable form for navigation. These two different approaches are used respectively by Alma (generic program animation system) and Cear (C Rooting Algorithm Visualization tool). For each tool several examples of visualization are shown in order to discuss the information that is included in the visualizations, visualization types and the use of Program Animation for Program Comprehension.