Jianjun Zhao, Shanghai Jiao Tong University, China (X10 team contact: Qiming Teng and Haichuan Wang)

Although many efforts have been made to improve the memory model and synchronization, atomicity violations that originate from buggy declarations of atomic blocks may still occur in X10 programs. The objective of this project is to develop a static approach to effectively and efficiently detect atomicity violations for X10 programs. In order to classify both “must” and “may” atomicity violations, we improve unserializable patterns of shared-memory accesses through considering the dependencies between the successive shared-memory accesses. We plan to devise a static analysis to produce sound detection results and eliminate false positives as much as possible. We will also utilize reduction techniques to guarantee the scalability of our approach. The benefits of this project are as follows: First, it provides debugging support for X10 programs through the detection of atomicity violations. Second, since our approach does not rely on the declarations of atomic blocks, it can be applied to infer atomic blocks or eliminate unnecessary atomic blocks. Third, inter-activity data-flow analysis is extremely difficult due to the explosion of state space of activity interleavings; this project partly concerns inter-activity data-flow analysis, and therefore has the potential to provide experience or theoretical foundation in this field. Finally, our approach can be integrated with testing to provide more effective and efficient debugging support for X10 programs.