A power optimization method of deriving gated circuitry in an integrated circuit (IC) is provided. A design description of the IC is received and analyzed. A state machine is identified based on the analysis. One or more candidate blocks are determined to be capable of being disabled. At least one of the candidate blocks is selected based on one or more states of the state machine. A gating circuit is inserted for gating the selected candidate block(s). In another embodiment of power optimization, one or more state machines are identified and a synthesized netlist is generated. One or more candidate blocks in the synthesized netlist are determined to be capable of being disabled. At least one of the candidate blocks is selected based on one or more states in the state machine, and a gating circuit is inserted for gating the selected candidate block(s).