Static Analysis for Unaligned Collective Synchronization Matching for OpenSHMEM

The most critical step for static concurrency analysis of OpenSHMEM is to detect matching unaligned collective synchronization calls within an OpenSHMEM program. Concurrency analysis will be able to detect the regions in the code where two or more OpenSHMEM calls run concurrently and help identify parallel programming errors due to incorrect usage of OpenSHMEM library calls. For the concurrency analysis to be accurate the collective synchronization matching process must be accurate. This task is particularly challenging for OpenSHMEM programs since the OpenSHMEM library provides textually unaligned barriers over an active set in addition to the traditional barrier all statement. An active set is essentially a logical grouping of processing elements. In this paper we discuss our effort towards discovering and matching barrier calls in OpenSHMEM. We extend the OpenSHMEM Analyzer (OSA) to discover potential synchronization errors due to unaligned barriers in OpenSHMEM programs.