Interprocedural dependence analysis and parallelization

The area of dependence analysis has served as grounds for fruitful research as well as practical implementation. Compilers and tools that utilize dependence information can generate code that takes advantage of parallel resources and storage hierarchies on modern architectures. Here, we offer some historical background on the context and thinking that fostered our 1986 paper. We also attempt to summarize the direction research in this area has taken since the paper's appearance.We present a method that combines a deep analysis of program dependences with a broad analysis of the interaction among procedures. The method is more efficient than existing methods: we reduce many tests, performed separately by existing methods, to a single test. The method is more precise than existing methods with respect to references to multi-dimensional arrays and dependence information hidden by procedure calls. The method is more general than existing methods: we accommodate potentially aliased variables and structures of differing shapes that share storage. We accomplish the above through a unified approach that integrates subscript analysis with aliasing and interprocedural information.