An improved register allocation algorithm for the WAM model

An improved adaptable unification order algorithm is presented. It is used in register allocation for a Warren abstract machine (WAM) Prolog implementation. The algorithm is based on the division of a clause into chunks. The purpose is to generate better Prolog codes for programs so that they have fewer instructions and data movements in execution. It is realized by a good conflict handling algorithm and by an adaptable processing order method of compound arguments. The method has been proved to be efficient in practice. >