12. The method of claim 11 , further comprising partitioning the reference library into a plurality of cells, each cell being associated with a corresponding size.
12. The method of claim 11 , further comprising partitioning the reference library into a plurality of cells, each cell being associated with a corresponding size. 16. The method of claim 12 , wherein at least one of the cells includes sub-cells, the sub-cells being distributed over corresponding different CPUs.