Program slicing is an effective technique for an- alyzing concurrent programs. However, when a conventional closure-based slicing algorithm for sequential programs is ap- plied to a concurrent interprocedural program,...Program slicing is an effective technique for an- alyzing concurrent programs. However, when a conventional closure-based slicing algorithm for sequential programs is ap- plied to a concurrent interprocedural program, the slice is usually imprecise owing to the intransitivity of interference dependence. Interference dependence arises when a state- ment uses a variable defined in another statement executed concurrently. In this study, we propose a global dependence analysis approach based on a program reachability graph, and construct a novel dependence graph called marking-statement dependence graph （MSDG）, in which each vertex is a 2-tuple of program state and statement. In contrast to the conven- tional program dependence graph where the vertex is a state- ment, the dependence relation in MSDG is transitive. When traversing MSDG, a precise slice will be obtained. To en- hance the slicing efficiency without loss of precision, our slic- ing algorithm adopts a hybrid strategy. The procedures con- taining interaction statements between threads are inlined and sliced by the slicing algorithm based on program reachability graphs while allowing other procedures to be sliced as se- quential programs. We have implemented our algorithm and three other representative slicing algorithms, and conducted an empirical study on concurrent Java programs. The exper- imental results show that our algorithm computes more pre- cise slices than the other algorithms. Using partial-order re- duction techniques, which are effective for reducing the size of a program reachability graph without loss of precision, ouralgorithm is optimized, thereby improving its performance to some extent.展开更多
文摘Program slicing is an effective technique for an- alyzing concurrent programs. However, when a conventional closure-based slicing algorithm for sequential programs is ap- plied to a concurrent interprocedural program, the slice is usually imprecise owing to the intransitivity of interference dependence. Interference dependence arises when a state- ment uses a variable defined in another statement executed concurrently. In this study, we propose a global dependence analysis approach based on a program reachability graph, and construct a novel dependence graph called marking-statement dependence graph （MSDG）, in which each vertex is a 2-tuple of program state and statement. In contrast to the conven- tional program dependence graph where the vertex is a state- ment, the dependence relation in MSDG is transitive. When traversing MSDG, a precise slice will be obtained. To en- hance the slicing efficiency without loss of precision, our slic- ing algorithm adopts a hybrid strategy. The procedures con- taining interaction statements between threads are inlined and sliced by the slicing algorithm based on program reachability graphs while allowing other procedures to be sliced as se- quential programs. We have implemented our algorithm and three other representative slicing algorithms, and conducted an empirical study on concurrent Java programs. The exper- imental results show that our algorithm computes more pre- cise slices than the other algorithms. Using partial-order re- duction techniques, which are effective for reducing the size of a program reachability graph without loss of precision, ouralgorithm is optimized, thereby improving its performance to some extent.
