A hierarchical constraint graph generation and compaction system for symbolic layout

A novel approach and system for graph-oriented layout compaction for large symbolic layout designs is presented. Hierarchical compaction is performed by generating geometrical interfaces for compacted subcells which are used as rigid nodes in graphs at higher hierarchical levels. Further reduction of the complexity of graph generation and compaction is achieved by setting only local constraints in the graphs, which requires an iterative graph-generation/compaction scheme.<
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