Global Code Selection of Directed Acyclic Graphs

Andreas Fauth, Günter Hommel, Alois C. Knoll, Carsten Müller

Abstract: We describe a novel technique for code selection based on data-flow graphs, which arise naturally in the domain of digital signal processing. Code selection is the optimized mapping of abstract operations to partial machine instructions. The presented method performs an important task within the retargetable microcode generator CBC, which was designed to cope with the requirements arising in the context of custom digital signal processor (DSP) programming. The algorithm exploits a graph representation in which control-flow is modeled by scopes.