Patent ID: 7900020

Claim:
A data processor operable to process data, said data processor comprising: a cache in which a storage location of a data item within said cache is identified by an address, said cache comprising a plurality of storage locations and said data processor comprising a cache directory operable to store an address indicator for each storage location comprising stored data; a hash value generator operable to generate a generated hash value from at least some of said bits of said address said generated hash value having fewer bits than said address; a buffer operable to store a plurality of hash values relating to said plurality of storage locations within said cache; wherein in response to a request to access said data item said data processor is operable to compare said generated hash value with at least some of said plurality of hash values stored within said buffer and in response to a match to indicate a indicated storage location of said data item; and said data processor is operable to access one of said address indicators stored within said cache directory corresponding to said indicated storage location and in response to said accessed address indicator not matching said address said data processor is operable to invalidate said indicated storage location within said cache, wherein said data processor is operable to access at least one further address indicator stored within said cache directory and in response to one of said at least one further address indicator indicating said address said data processor is operable to write said generated hash value to a location within said hash buffer corresponding to said storage location indicated by said one of said at least one further address indicators and to invalidate a location within said hash buffer corresponding to said indicated storage location.