A power aware front-end unit for a processor may include a UOP cache that disables
other circuitry within the front-end unit. In an embodiment, a front-end unit may
disable instruction synchronization circuitry, instruction decode circuitry and,
optionally, instruction fetch circuitry while instruction look-ups are underway
in both a block cache and an instruction cache. If the instruction look-up indicates
a miss, the disabled circuitry thereafter may be enabled.