Incremental Flow Analysis

Abstract interpretation is a technique for ow analysis widely used in the area of logic programming. Until now it has been used only for the global compilation of Prolog programs. But the programming language Prolog enables the programmer to change the program during run time using the built-in predicates assert and retract. To support the generation of ecient code for programs using these dynamic database predicates we extended abstract interpretation to be executed incrementally. The aim of incremental abstract interpretation is to gather program information with minimal reinterpretation at a program change. In this paper we describe the implementation of incremental abstract interpretation and the integration in our VAM 1P based Prolog compiler. Preliminary results show that incremental global compilation can achieve the same optimization quality as global compilation with little additional cost.