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Compacting MIMOLA microcode

Published:01 June 1988Publication History
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Abstract

We address the problem of reducing the word length of microprograms. Two techniques are described: overlaying of fields and encoding of the microprogram. Formal analysis are presented of different encoding methods, assuming a VLSI implementation. A maximal encoding strategy appears to be the most area-efficient. Field overlaying is formulated as a clique-partitioning problem, and an efficient and practical clique-partitioning algorithm is presented. Based on these results, a microward compaction strategy that consists of field overlaying followed by maximal encoding has been implemented for the MIMOLA synthesis system (a design tool that generates excessively long microinstructions). Some considerations that are relevant to MIMOLA, and probably general to other similar tools, are discussed.

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              cover image ACM SIGMICRO Newsletter
              ACM SIGMICRO Newsletter  Volume 19, Issue 1-2
              June 1988
              66 pages
              ISSN:1050-916X
              DOI:10.1145/62197
              Issue’s Table of Contents

              Copyright © 1988 Authors

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              Association for Computing Machinery

              New York, NY, United States

              Publication History

              • Published: 1 June 1988

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