The impact of unresolved branches on branch prediction scheme performance

Examines the benefits of the early resolution of branch instructions and the impact of unresolved branches on history-based branch prediction schemes by using two new metrics that are more revealing than branch prediction accuracy alone. The authors first briefly review a number of branch prediction schemes and introduce two new branch prediction scheme performance metrics. They then utilize these metrics to gauge the improvement in branch prediction scheme performance when only the outcomes of unresolved branches are predicted. Finally, they examine two approaches for handling multiple unresolved branches in history-based branch prediction schemes, and determine that prediction accuracy remains quite stable when older branch histories are used