Is addition(+) operation more complex than comparison operation (>), both in integer as well as floating point arithmetic? I would appreciate answer in the context of both microprocessor- and FPGA-based systems.

My thought:
I think comparison and addition are the same thing when we talk about microprocessor-based systems because comparison a>b can be solved by checking the sign bit of (a-b), i.e, an addition operation. But, in the context of FPGA-based systems, I guess the complexity of comparison operator can be reduced?