A processor includes a front end to receive an instruction, a decoder to decode the instruction, a set operations logic unit (SOLU) to execute the instruction, and a retirement unit. The SOLU includeslogic to store a first set of key-value pairs in a content-associative data structure, to receive a second set of key-value pairs, and to identify key-value pairs in the two sets with matching keys.The SOLU includes logic to add the second set of key-value pairs to the first set to produce an output set, and to apply an operation to the values of key-value pairs with matching keys, generating asingle value for the matching key. The SOLU includes logic to produce an output set that includes key-value pairs from the first set with matching keys, and to discard key-value pairs from the first set with unique keys.