AUTOMATIC MODE INFERENCE FOR PROLOG PROGRAMS.

The problem of automatically inferring the modes of the predicates in a program is considered. The dataflow analysis used is more powerful than approaches relying on syntactic characteristics of programs. A sound and efficient treatment of variable aliasing in mode inference is given. By propagating instantiation information using state transformations, rather than through dependencies between variables, greater precision in the treatment of unification than in previous studies is achieved. Several optimizations to improve the performance of the mode inference algorithm are described, as are various program optimizations based on mode information.