Sub-operation parallelism optimization in SIMD processor core synthesis

Hideki Kawazu, Jumpei Uchida, Yuichiro Miyaoka, Nozomu Togawa, Masao Yanagisawa, Tatsuo Ohtsuki

    Research output: Contribution to journalArticle


    A b-bit SIMD functional unit has n k-bit sub-functional units in itself, where b = k × n. It can execute n-parallel k-bit operations. However, all the b-bit functional units in a processor core do not necessarily execute n-parallel operations. Depending on an application program, some of them just execute n/2-parallel operations or even n/4-parallel operations. This means that we can modify a b-bit SIMD functional unit so that it has n/2 k-bit sub-functional units or n/4 k-bit sub-functional units. The number of k-bit sub-functional units in a SIMD functional unit is called sub-operation parallelism. We incorporate a sub-operation parallelism optimization algorithm into SIMD functional unit optimization. Our proposed algorithm gradually reduces sub-operation parallelism of a SIMD functional unit while the timing constraint of execution time satisfied. Thereby, we can finally find a processor core with small area under the given timing constraint. We expect that we can obtain processor core configurations of smaller area in the same timing constraint rather than a conventional system. The promising experimental results are also shown.

    Original languageEnglish
    Pages (from-to)876-883
    Number of pages8
    JournalIEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences
    Issue number4
    Publication statusPublished - 2005



    • Hardware/software cosynthesis
    • Hardware/software partitioning
    • Packed SIMD type operation
    • Processor synthesis
    • Sub-operation parallelism

    ASJC Scopus subject areas

    • Electrical and Electronic Engineering
    • Hardware and Architecture
    • Information Systems

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