Machine-independent register allocation

Abstract

The context of this paper is a machine-independent Pascal optimizer that transforms an intermediate stack-machine pseudo-code program into a generally smaller and faster pseudo-code program. The emphasis of this current paper is on the approach taken for mapping registers and storage, using an abstract but practical definition of the target machine's storage hierarchy. A companion paper [7] describes the overall optimizer project. After starting on this project, additional input became available from a Fortran-to-Pcode compiler written at Stanford [2]. Our storage mapping design is sufficiently robust that the addition of Fortran EQUIVALENCE and COMMON statements required no changes.