A macro-generable language for the 360 computers
M Griffiths, Mikaël Peltier · ITNOW · 1969
A recent paper in The Computer Bulletin [1] prompts us to add our experience of using OS/360 macros to write good assembly language programs. Our aim was to provide a seemingly high-level language by macros so that a program can at the same time be both efficient and clear. The level of the language is not far removed from that of PL/360 [2], although there are differences in implementation, especially in register usage. The language falls into three parts; the subroutine and module control, statement control, and special purpose statements. The first two are of general interest and the last is directed more particularly to non-numerical programming and compiler writing. These provide subroutines in modules which can be assembled individually. Independent assembly is important for large programs, since the current assembler is extremely slow. The subroutines can be indefinitely recursive and the mechanism must be efficient, since the programs involved are collections of large numbers of interlinked simple operations. They would be relatively slow in a classical compiler language. A module is a succession of routines headed by