Can Dataflow Subsume Von Neumann Computing?

We explore the question: "What can a von Neumann processor borrow from dataflow to make it more suitable for a multiprocessor?" Starting with a simple, "RISC-like" instruction set, we show how to change the underlying processor organization to make it multithreaded. Then, we extend it with three instructions that give it a fine-grained, dataflow capability. We call the result P-RISC, for "Parallel RISC." Finally, we discuss memory support for such multiprocessors. We compare our approach to existing MIMD machines and to other dataflow machines.