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Tree compaction of microprograms

Published:01 December 1983Publication History
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Abstract

Although Fisher's trace scheduling procedure for global compaction may produce significant reduction in execution time of compacted microcode, the growth of memory size by extensive copying of blocks can be enormous. In the worst case, the memory size can grow exponentially [FIS81a] and the complex bookkeeping stage of the trace scheduling is an obstacle to implementation.A technique called tree compaction, which is based on the trace scheduling, is proposed to mitigate these drawbacks. Basically, it partitions a given set of microprogram blocks into tree-shaped subsets and applies the idea of trace scheduling on each tree-shaped subset separately. It achieves almost all of the compaction of the Fisher's trace scheduling procedure except that which causes copying of blocks. Preliminary tests indicate that tree compaction gives almost as short execution time as trace scheduling but with much less memory. The paper includes such an example.

References

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  • Published in

    cover image ACM SIGMICRO Newsletter
    ACM SIGMICRO Newsletter  Volume 14, Issue 4
    December 1983
    205 pages
    ISSN:1050-916X
    DOI:10.1145/1096419
    Issue’s Table of Contents

    Copyright © 1983 Authors

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    Association for Computing Machinery

    New York, NY, United States

    Publication History

    • Published: 1 December 1983

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