Hierarchical microprogram generating system

Abstract

A general purpose microprogram generating system has been developed to compose, together with a hardware/microprogram debugger, a general purpose development support system for LSI Processor Modules such as Am2900, MMI6700, and/or MACROLOGIC. The microprogram generator, designed to be applicable to a wide variety of microinstruction sets from vertical to horizontal including sophisticated control schemes like pipelining, has a three-level hierarchical structure. The lowest level generator is a microassembler, which has already been applied to many computers and shown its easiness of defining instructon sets and high-speed generation of object microcodes. The second level generator is an optimizing assembler, which translates a sequence of microoperations to an optimum sequence of microinstructions considering data dependency and concurrent executability of microoperations on a defined object machine. The highest level generator is the high-level microprogramming language compiler which generates an optimum sequence of microoperations utilizing techniques of optimization for high-level language compilers. Example definitions of a microinstruction set and an object machine, source programs, and object listings show the effectiveness of the hierarchical microprogram generating system.