Active Loop Detection for Applications that Access Databases

Abstract

We present Shear, a new system that observes and manipulates the interaction between an application and its surrounding environment to learn a model of the behavior of the application. Shear implements active loop detection to infer the loop structures in the application. This technique repeatedly presents the application with the same input, altering the program's interaction with the environment at precisely chosen execution points to elicit different program behaviors depending on the loop structure in the application. The ability to alter interactions between the application and the environment enables Shear to infer a broader range of loop structures otherwise undetectable given only the ability to observe application behavior. Active loop detection therefore enables Shear to infer a broader range of loop structures than previous approaches.