Symmetry-aware placement with transitive closure graphs for analog layout design

A new scheme is proposed to use transitive closure graph (TCG) to explore the full symmetry solution space in analog layout design. We define a set of TCG symmetric-feasible conditions and show that it is extremely useful in reducing the solution space. A method is presented for generating random symmetric-feasible TCGs in O(n) time preserving the TCG closure property. Experimental results have confirmed the effectiveness of the proposed symmetry-aware TCG placement algorithm.