OpenMPspy: Leveraging Quality Assurance for Parallel Software

OpenMP is widely used in practice to create parallel software, however, software quality assurance tool support is still immature. OpenMPspy introduces a new approach, with a short-term and a long-term perspective, to aid software engineers write better parallel programs in OpenMP. On the one hand, OpenMPspy acts like an online-debugger that statically detects problems with incorrect construct usage and which reports problems while programmers are typing code in Eclipse. We detect simple slips as well as more complex anti-patterns that can lead to correctness problems and performance problems. In addition, OpenMPspy can aggregate statistics about OpenMP language usage and bug patterns from many projects. Insights generated from such data help OpenMP language designers improve the usability of constructs and reduce error potential, thus enhancing parallel software quality in the long run. Using OpenMPspy, this paper presents one of the first detailed empirical studies of over 40 programs with more than 4 million lines of code, which shows how OpenMP constructs are actually used in practice. Our results reveal that constructs believed to be frequently used are actually rarely used. Our insights give OpenMP language and compiler designers a clearer picture on where to focus the efforts for future improvements.