Visualizing constituent behaviors within executions

In this New Ideas and Emerging Results paper, we present a novel visualization, THE BRAIN, that reveals clusters of source code that co-execute to produce behavioral features of the program throughout and within executions. We created a clustered visualization of source-code that is informed by dynamic control flow of multiple executions; each cluster represents commonly interacting logic that composes software features. In addition, we render individual executions atop the clustered multiple-execution visualization as user-controlled animations to reveal characteristics of specific executions-these animations may provide exemplars for the clustered features and provide chronology for those behavioral features, or they may reveal anomalous behaviors that do not fit with the overall operational profile of most executions. Both the clustered multiple-execution view and the animated individual-execution view provide insights for the constituent behaviors within executions that compose behaviors of whole executions. Inspired by neural imaging of human brains of people who were subjected to various external stimuli, we designed and implemented THE BRAIN to reveal program activity during execution. The result has revealed the principal behaviors of execution, and those behaviors were revealed to be (in some cases) cohesive, modular source-code structures and (in other cases) cross-cutting, emergent behaviors that involve multiple modules. In this paper, we describe THE BRAIN and envisage the uses to which it can be put, and we provide two example usage scenarios to demonstrate its utility.