Efficient computation of May-Happen-in-Parallel information for concurrent Java']Java programs

Modeling of runtime threads in static analysis of concurrent programs plays an important role in both reducing the complexity and improving the precision of the analysis. Modeling based on type based techniques merges all runtime instances of a particular type and thereby introduces inaccuracy in the analysis. Other approaches model individual runtime threads explicitly in the analysis and are of high complexity. In this paper we introduce a thread model that is both context and flow sensitive. Individual thread abstractions are identified based on the context and multiplicity of the creation site. The interaction among these abstract threads are depicted in a tree structure known as Thread Creation Tree (TCT). The TCT structure is subsequently exploited to efficiently compute May-Happen-in-Parallel (MHP) information for the analysis of multi-threaded programs. For concurrent Java programs, our MHP computation algorithm runs 1.77x (on an average) faster than previously reported MHP computation algorithm.