OPSILA: a vector and parallel processor

A multiprocessor machine with two operating modes and simple synchronization mechanisms is discussed. The operating modes are the vector single-instruction multiple-data (SIMD) mode and the parallel single program stream, multiple data stream (SPMD) mode. Synchronizations are reduced to the switching between these two modes. Mixing these two operating modes offers the programmer a comfortable programming environment: vector parallelization is performed by the compiler and the hardware, and, since SPMD parallelization requires mainly the partitioning of the entire set of data, the synchronizations are then often obvious