An improved placement and routing method for circuit simulation includes receiving setup input controls to set up an initial arrangement of two blocks (e.g., a synthesized block and an IP block), and a designation of permutable interconnections; performing permutations of permutable interconnect signals on the, e.g., design block (or any other block)-IP block arrangement to determine an optimal permutation; compiling a bitstream comprising a final placement and route of a circuit based on the optimal permutation and generating the bitstream to be loaded onto a target FPGA; and sending the final order of the permutable signals to a permutable signals control memory structure.