Ecient Execution of Pure Object-Oriented Programs by Follow-up Compilation

Dynamic type checking and method binding slows pure object-oriented programs such as those written in Smalltalk. Dynamic method lookup is needed to support method overriding and type-method conformance. We have developed a platform independent technique that imple-ments method overriding eciently for pure object-oriented languages. The technique involves binding non-overridden method calls at compile time. The overridden method calls are also re-solved (and bound) statically using simple inferences. Overridden method bindings are corrected dynamically using an Overridden Method Dictionary. Using simulations, we demonstrate that this technique oers 35%-70 % reduction in the average method lookup delay over the Berkeley Smalltalk implementation. This technique has very low compile time overhead, memory over-head, does not need specialized hardware and allows shared code pages in concurrent programs. For programs which may be re-used it is proper to have a follow-up compilation to generate ecient code after the program development is complete