1. A method for processing a circuit design, comprising: determining with a processor groups of placed, replicate logic blocks in a circuit design that is represented in a memory, wherein the replicate logic blocks in each group have equivalent logic, have corresponding input pins and corresponding output pins, and each set of corresponding input pins is coupled to a common source; determining with the processor, for the replicate logic blocks in each group, whether or not to merge replicate logic blocks in a subset of the replicate logic blocks into a respective single replacement logic block for the subset; replacing in the circuit design by the processor, in response to determining to merge the replicate logic blocks in the subset, the replicate logic blocks in the subset with the respective replacement logic block; and storing the circuit design having the replacement logic block in the memory by the processor.