Patent ID: 9703948
Date: 2017-07-11
CPC Classifications: G06F

Claim:
1. A processor comprising: a decode unit to decode a return target restrictive return from procedure (RTR return) instruction; a return target restriction unit, which includes at least some circuitry, coupled with the decode unit, and responsive to the RTR return instruction, to determine whether to restrict an attempt by the RTR return instruction to make a control flow transfer to an instruction at a return address corresponding to the RTR return instruction, based on compatibility of a type of the instruction at the return address with the RTR return instruction, and based on compatibility of first return target restrictive information (RTR information) of the RTR return instruction with second RTR information of the instruction at the return address; and a control flow transfer unit coupled with the return target restriction unit and with the decode unit, the control flow transfer unit, responsive to the RTR return instruction, to transfer control flow to the instruction at the return address when the return target restriction unit determines not to restrict the attempt.