From Control Flow to Dataflow

Are imperative languages tied inseparably to the von Neumann model or can they be implemented in some natural way on dataflow architectures? In this paper, we show how imperative language programs can be translated into dataflow graphs and executed on a dataflow machine like Monsoon. This translation can exploit both fine-grain and coarsegrain parallelism in imperative language programs. More importantly, we establish a close connection between our work and current research in the imperative languages community on data dependencies, control dependencies, program dependence graphs, and static single assignment form. These results suggest that dataflow graphs can serve as an executable intermediate representation in ∗This research was supported by an NSF Presidential Young Investigator award (NSF grant #CCR–8958543), and grants from the General Electric Corp. the Math Sciences Institute of Cornell, and the Digital Equipment Corporation †The authors can be reached at electronic mail addresses [email protected] and [email protected]. parallelizing compilers.