A modified relay-race algorithm for floorplanning in PCB and IC design

Floorplanning is a fundamental design step in the physical design of printed circuit boards (PCBs) and integrated circuits (ICs), as it handles the complexity of layout design. From a computational point of view, the floorplanning problem is an NP hard problem, and the size of the search space grows exponentially with increasing numbers of modules. Thus, the algorithm used is an essential factor for speed and quality of the floorplanning process. Although polynomial-time floorplanning algorithms can be implemented when solution space is limited to slicing floorplans, optimal solutions often exist only in the nonslicing floorplan search space. Various stochastic algorithms such as simulated annealing (SA), the genetic algorithm (GA), and the relay race algorithm (RRA) can be used with nonslicing floorplans. In this paper, a modified relay race algorithm (MRRA) is proposed. Based on the experimental results utilizing MCNC benchmarks, MRRA improved both solution quality and run time for area optimization when compared with SA, GA, and RRA.