Floorplanning using a tree representation: A summary

T. Takahashi, P. N. Guo, C. K. Cheng, T. Yoshimura

    Research output: Contribution to journalArticle

    2 Citations (Scopus)

    Abstract

    We present an ordered tree (O-tree) structure to represent nonslicing floorplans. The O-tree uses only n (2 + [lg n]) bits for a floorplan of n rectangular blocks. We define an admissible placement as a compacted placement in both X and y directions. For each admissible placement, we can find an O-tree representation. We show that the number of possible O-tree combinations is 0(n!2 2n-2/n 1.5). This is very concise compared to a sequence pair representation that has O((n!) 2) combina-tions. The approximate ratio of sequence pair and O-tree combinations is O(n 2(n/4e) n). The complexity of an O-tree is even smaller than a binary tree structure for a slicing floorplan that has O(n!2 5n-3/n 1.5) combinations. Given an O-tree, it takes only linear time to construct the placement and its constraint graph. We have developed a deterministic floorplanning algorithm utilizing the structure of O-tree. Empirical results on MCNC (www.mcnc.org) benchmarks show promising performance with average 16% improvement in wire length and 1% less dead space over the previous central processing unit (CPU) intensive cluster refinement method.

    Original languageEnglish
    Pages (from-to)26-29
    Number of pages4
    JournalIEEE Circuits and Systems Magazine
    Volume3
    Issue number2
    DOIs
    Publication statusPublished - 2003 Jun

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    Binary trees
    Program processors
    Wire

    ASJC Scopus subject areas

    • Engineering(all)
    • Hardware and Architecture

    Cite this

    Floorplanning using a tree representation : A summary. / Takahashi, T.; Guo, P. N.; Cheng, C. K.; Yoshimura, T.

    In: IEEE Circuits and Systems Magazine, Vol. 3, No. 2, 06.2003, p. 26-29.

    Research output: Contribution to journalArticle

    Takahashi, T, Guo, PN, Cheng, CK & Yoshimura, T 2003, 'Floorplanning using a tree representation: A summary', IEEE Circuits and Systems Magazine, vol. 3, no. 2, pp. 26-29. https://doi.org/10.1109/MCAS.2003.1242834
    Takahashi, T. ; Guo, P. N. ; Cheng, C. K. ; Yoshimura, T. / Floorplanning using a tree representation : A summary. In: IEEE Circuits and Systems Magazine. 2003 ; Vol. 3, No. 2. pp. 26-29.
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