Automated Testing of Definition-Use Data Flow for Multithreaded Programs

With the advent of multicore processors, there is a trend towards multithreading to take advantage of parallel computing resources. Due to greatly increased complexity, programmers need effective testing methodology that can thoroughly test multithreaded programs. There has been significant progress based on symbolic execution that attempts to exhaustively explore all the intra-thread paths and inter-thread interleavings. However, such testing approach faces two insuperable challenges. Firstly, exploring an astronomically large number of paths and interleavings limits its scalability. Secondly, a path itself does not directly help programmers understand program behavior. In this paper, we propose an alternate testing methodology that focuses on definition-use data flow instead of paths/interleavings. Such approach not only leads to orders of magnitude reduction in testing complexity, but also gives programmers direct help on examining the shared variable usage in a multithreaded program.