Patent ID: 8874880

Claim:
A method for tracking instructions, in a processor, the method comprising: receiving, by a completion unit in the processor, an instruction group for a thread to add to a table to form a received instruction group; responsive to receiving, by the completion unit, the received instruction group, determining, by the completion unit, whether an entry is present that contains a previously stored instruction group in a first location and has space for storing the received instruction group; responsive to the entry being present, storing, by the completion unit, the received instruction group in a second location in the entry to form a stored instruction group; receiving, by the completion unit, an identification of a selected instruction group for removal from the table; responsive to receiving, by the completion unit, the identification of the selected instruction group, determining, by the completion unit, whether the selected instruction group can be removed; and responsive to the selected instruction group not being able to be removed, generating an error.