Abstract

To use modern hardware effectively, compilers need extensive control-flow information. Unfortunately, the frequent method invocations in object-oriented languages obscure control flow. In this paper, we describe and evaluate a range of analysis techniques to convert method invocations into direct calls for statically-typed object-oriented languages and thus improve control-flow information in object-oriented languages. We present simple algorithms for type hierarchy analysis, aggregate analysis, and interprocedural and intraprocedural type propagation. These algorithms are also fast, O(jproceduresj P procedures p n p v p ) worst case time (linear in practice) for our slowest analysis, where n p is the size of procedure p and v p is the number of variables in procedure p, and are thus practical for use in a compiler. When they fail, we introduce cause analysis to reveal the source of imprecision and suggest where more powerful algorithms may be warranted. We show that our simple an...

Citations