Parallel loop transformation technique for efficient race detection

Races might result in unintended nondeterministic execution of parallel programs and thus race detection is one of the critical issues to be resolved in debugging of shared-memory parallel programs. On-the-fly race detection techniques have been developed as one of approaches for the problem. However on-the-fly race detection techniques suffer from the huge run-time overhead because the whole execution behavior of the program being debugged must be monitored at run-time. In this paper we present a practical loop transform technique which can significantly reduce the monitoring overhead required for detecting races on-the-fly in parallel programs. Our technique achieves the improvement by minimizing the number of iteration counts to be monitored of each parallel loop by transforming the original loop with the technique. An experimental performance measurement of our technique shows dramatic improvement on the monitoring overhead and it detects more races than those detected by traditional on-the-fly techniques.