Sequential and Selective Recovery Mechanism for Value Misprediction

Value prediction is a technique to obtain performance gains by supplying earlier source values of its data dependent instructions using predicted value of a instruction. To fully exploit the potential of value speculation, however, the efficient recovery mechanism is necessary in case of value misprediction. In this paper, we propose a sequential and selective recovery mechanism for value misprediction. It searches data dependency chain of the mispredicted instruction sequentially without pipeline stalls and adverse impact on clock cycle time. In our scheme, only the dependent instructions on the predicted instruction is selectively squashed and reissued in case of value misprediction.