Dynamic branch prediction for branch instructions with multiple targets

摘要

A method and apparatus for dynamically predicting the outcome and the target address of a multiple-target branch instruction, where the multiple-target branch instruction contains at least two potential target addresses, not including the fall through address. In addition, this method and apparatus can also be used to predict multiple single-target branches simultaneously. The apparatus stores information indicating the outcome of previous executions and predictions of the multiple-target branch instruction in a branch prediction table. In addition, multiple target addresses (at least two) are associated with the multiple-target branch instruction. Using the information indicating the outcome of the previous execution of the multiple-target branch instruction, the apparatus predicts the outcome of a next execution of the multiple-target branch instruction, and predicts which, if any, of the target addresses associated with the multiple-target branch instruction, will be taken.