Protocol Specialization

Abstract

In component-based programming, the programmer assembles applications from prefabricated components. The assembly process has two main steps: adapting a component by tweaking its configuration parameters, and connecting components by gluing output interfaces to input interfaces. While convenient, this approach may give rise to code bloat and inefficiency because prefabricated code is overly general, by necessity. The present work addresses ways to remove unnecessary code during the deployment of a closed set of components by using program specialization. Our framework models components at the intermediate language level as systems of concurrent functional processes which communicate via channels. Each channel acts as a component connector with the interface determined by the channel's protocol. We present an analysis that determines the minimum protocol required for each process and specify the specialization of a process with respect to a desired protocol, thereby removing unnecessary code. The resulting specialization algorithm is unique in that it processes a concurrent base language, terminates always, and is guaranteed not to expand the program beyond its original size.