Introduction to Split-C

Split-C is a parallel extension of the C programming language primarily intended for distributed memory multiprocessors. It is designed around two objectives. The first is to capture certain useful elements of shared memory, message passing, and data parallel programming in a familiar context, while eliminating the primary deficiencies of each paradigm. The second is to provide efficient access to the underlying machine, with no surprises. (This is similar to the original motivation for C---to provide a direct and obvious mapping from high-level programming constructs to low-level machine instructions.) Split-C does not try to obscure the inherent performance characteristics of the machine through sophisticated transformations. This combination of generality and transparency of the language gives the algorithm or library designer a concrete optimization target. This document describes the central concepts in Split-C and provides a general introduction to programming in the language. Both the language and the document are undergoing active development, so please view the document as working notes, rather than the final language definition