Molecule: a language construct for layered development of parallel programs

A new language construct, called molecule, is described for the efficient implementation of algorithms on parallel computers. A molecule can be considered a procedure associated with a molecule type. Each molecule type characterizes a particular computation mode (sequential, pipelining, array processing, dataflow, multiprocessing, etc.). Basic concepts of molecule are introduced with a procedural language, called PAL. A concrete example is presented to illustrate layered software development using PAL on a multicomputer (the iPSC). It is concluded that high-level languages, augmented with the molecule construct, offer application flexibility, user friendliness, and efficiency in implementing parallel programs