In a data processing system a plurality of signals associated with an operation are received during execution of the operation. In response to an indication that the operation is a multiphase operation, during execution of the operation, selection logic, during a first phase of the multiphase operation, selects and outputs as a trace signal a first signal of the plurality of signals, and during a second phase of the multiphase operation, selects and outputs as the trace signal a second signal of the plurality of signals.