Circuit floorplanning is performed on a combination central processing unit and multiprocessor. A B*-tree data structure of a floorplan and circuit related constants reside in a central processing unit data storage. The B* tree structure of a floorplan along and said circuit related constants are copied to a multiprocessor data storage where multiple thread blocks, each consisting of a single thread, copy the tree to their own shared memories. The multiprocessor concurrently evaluates different moves in different thread blocks. The multiprocessor then evaluates objective function results and stores those results. The best result for floorplanning is selected from the multiple circuit evaluations.