Using types to analyze and optimize object-oriented programs

Abstract

Object-oriented programming languages provide many software engineering benefits, but these often come at a performance cost. Object-oriented programs make extensive use of method invocations and pointer dereferences, both of which are potentially costly on modern machines. We show how to use types to produce effective, yet simple, techniques that reduce the costs of these features in Modula-3, a statically typed, object-oriented language. Our compiler performs type-based alias analysis to disambiguate memory references. It uses the results of the type-based alias analysis to eliminate redundant memory references and to replace monomorphic method invocation sites with direct calls. Using limit, static, and running time evaluation, we demonstrate that these techniques are effective, and sometimes perfect for a set of Modula-3 benchmarks.