an experiment to improve operand addressing
MCODE is a high-level language, stack machine designed to support strongly-typed, Pascal-based languages with a variety of data types in a modular programming environment. The instruction set, constructed for efficiency and extensibility, is based on an analysis of 120,000 lines of Pascal programs. The design was compared for efficiency with the instruction sets of the Digital Equipment PDP-11 and VAX by examining the generated code from the same compiler for all three machines. In addition, the original design choices were tested by analyzing the generated code from 19,000 lines of StarMod programs. As a result of this iterative experiment, we have summarized our observations in an efficient reorganization of the VAX's addressing modes.
experience code language stack machine design support types data modular program programming environment instruction efficiency extensibility analysis digitize compilation iter observability addressing modes computer architecture