Abstract: Systems and methods for branch prediction include identifying a subset of branch instructions executable by a processor as a neural subset of branch instructions, based on information obtained from using an execution trace, wherein the neural subset of branch instructions are determined to have larger benefit from a neural branch predictor than a non-neural branch predictor. The neural branch predictor is pre-trained for the neural subset based on the execution trace. Annotations are added to the neural subset of branch instructions, wherein the annotations are preserved across software revisions. At runtime, when the neural subset of branch instructions are encountered during any future software revision, the branch instructions thereof are detected as belonging to the neural subset of branch instructions based on the annotations, and the pre-trained neural branch predictor is used for making their branch predictions.

Abstract: Systems and methods for branch prediction include identifying a subset of branch instructions from an execution trace of instructions executed by a processor. The identified subset of branch instructions have greater benefit from branch predictions made by a neural branch predictor than branch predictions made by a non-neural branch predictor. During runtime, the neural branch predictor is selectively used for obtaining branch predictions of the identified subset of branch instructions. For remaining branch instructions outside the identified subset of branch instructions, branch predictions are obtained from a non-neural branch predictor. Further, a weight vector matrix comprising weight vectors for the identified subset of branch instructions of the neural branch predictor is pre-trained based on the execution trace.

Abstract: Systems and methods for branch prediction include identifying a subset of branch instructions from an execution trace of instructions executed by a processor. The identified subset of branch instructions have greater benefit from branch predictions made by a neural branch predictor than branch predictions made by a non-neural branch predictor. During runtime, the neural branch predictor is selectively used for obtaining branch predictions of the identified subset of branch instructions. For remaining branch instructions outside the identified subset of branch instructions, branch predictions are obtained from a non-neural branch predictor. Further, a weight vector matrix comprising weight vectors for the identified subset of branch instructions of the neural branch predictor is pre-trained based on the execution trace.

Abstract: Systems and methods for branch prediction include detecting a subset of branch instructions which are not fixed direction branch instructions, and for this subset of branch instructions, utilizing complex branch prediction mechanisms such as a neural branch predictor. Detecting the subset of branch instructions includes using a state machine to determine the branch instructions whose outcomes change between a taken direction and a not-taken direction in separate instances of their execution. For the remaining branch instructions which are fixed direction branch instructions, the complex branch prediction techniques are avoided.