Issue No.04 - August (1996 vol.16)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/40.526925
Subword Parallelism is a technique that enables the full use of word-oriented datapaths when dealing with lower-precision data. It is a form of low-cost, small-scale SIMD parallelism. This paper discusses the needs of subword parallelism, and gives an example of how it can be supported with a very small set of MAX-2 instructions. MAX-2 is the second generation of Multimedia Acceleration eXtensions introduced with the PA-RISC 2.0 processors. Because MAX-2 strives to be a minimal set supporting subword parallelism, we discuss both instructions included and excluded. Mix and Permute instructions are introduced as new simple yet powerful subword rearrangement primitives. We illustrate how programs with inherent data parallelism may be accelerated with subword parallel instructions. We also give many short examples capturing key aspects of the use of MAX-2 instructions.
subword parallelism, MAX-2, multimedia acceleration, instruction set extensions, SIMD, media processing, subword rearrangement, data parallelism.
Ruby B. Lee, "Subword Parallelism with MAX-2", IEEE Micro, vol.16, no. 4, pp. 51-59, August 1996, doi:10.1109/40.526925