Efficient Variable Ordering Heuristics for Shared ROBDD
نویسندگان
چکیده
Pi-Yu Chung, Ibrahim N. Hajj, and Janak H. Patel Coordinated Science Laboratory and Department of Electrical and Computer Engineering University of Illinois at Urbana-Champaign Abstract In this paper we describe several ordering heuristics for shared, Reduced and Ordered Binary Decision Diagrams(ROBDDs). These heuristics have been tested on ISCAS and MCNC benchmark circuits. In all examples, the ordering is accomplished in a few seconds and generates smaller shared ROBDDs than other previously proposed heuristics. The objective is to provide a fast way to generate shared ROBDDs of reasonable sizes, and the results could be used as a good initial solution to any semi-exhaustive ordering method [2, 3] to further reduce the sizes.
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