Patent ID: 6859875

Claim:
A data processing system having a first and a second mode of operation, comprising: a central processing unit having a first input to receive a first signal wherein a first state of the first signal enables the first mode of operation and a second state of the first signal enables the second mode of operation, wherein: the first mode of operation utilizes branch prediction; the second mode or operation utilizes substantially no branch prediction; and the central processing until comprise:. selecting circuitry having a first input for receiving a sequential address, a second input for receiving a target address, and a third input for receiving a control signal to select between the first input and the second input, and an output for providing one of the first input and the second input; an instruction fetch unit, coupled to the selecting circuitry, having a first output to provide the sequential address and a second output for providing the target address; and control circuitry coupled to the selecting circuitry having a first input to receive the first signal, having a first output to provide the control signal based on the first signal, having a second input to receive a condition signal, and having a third input to receive a branch decode signal, wherein the control signal is based further in part on the condition signal and the branch decode signal.