US Patent 7769983 Caching instructions for a multiple-state processor

A method and apparatus for caching instructions for a processor having multiple operating states. At least two of the operating states of the processor supporting different instruction sets. A block of instructions may be retrieved from memory while the processor is operating in one of the states. The instructions may be pre-decoded in accordance with said one of the states and loaded into cache. The processor, or another entity, may be used to determine whether the current state of the processor is the same as said one of the states used to pre-decode the instructions when one of the pre-decoded instructions in the cache is needed by the processor.