Patent ID: 7694068

Claim:
A content addressable memory (CAM) device, comprising: a CAM core including a CAM array having a plurality of rows of CAM cells, each row for storing a corresponding data word; circuitry for generating a result in response to a compare operation between a search key and the data words stored in the CAM array; and a re-entrant processor configured to selectively modify the search key by replacing selected portions of the search key with selected portions of one or more previous search keys and/or with selected portions of one or more previous results, wherein the compare operation is initiated by an initial instruction comprising key construction data that defines modification of the search key, wherein the key construction data comprises: a plurality of select bits sets, each select bit set for selecting one of the previous search keys or one of the previous results as source data for constructing a corresponding segment of a modified search key; and a plurality of key definition data sets, each key definition data set for determining which portion of the corresponding source data forms the corresponding segment of the modified search key.