Global methods in the flow graph approach to retargetable microcode generation

Abstract

We have reported on local retargetable microcode generation methods based on the flow graph model in previous papers. In this paper, we consider the extension of these methods to global retargetable microcode generation. This includes intermediate representations of basic blocks containing control flow directives and their construction from global program dags, resource allocation and its interaction with code generation, machine-independent semantics and procedures for global microcode generation, and global compaction. The emphasis is on issues and promising directions for research on global methods vis a vis final results and definitive answers, as it reflects the early stages of our research.