| 摘要 |
A method and apparatus for obtaining non-contiguous blocks of instruction in a data processing system is disclosed. The apparatus comprises an instruction cache means for providing a first plurality of instructions and branch logic means for receiving the first plurality of instructions and for providing branch history information about the first plurality of instructions. The apparatus further includes an auxiliary cache means for receiving a second plurality of instructions based upon the branch history information. The auxiliary cache means overlays at least a one of the second plurality of instructions if there is a branch in the first plurality of instructions and the branch is to the second plurality of instructions. Thus the apparatus can use branch history information and an auxiliary cache to fetch multiple noncontiguous groups of instructions in a single cycle. Furthermore, the technique allows noncontiguous fetching to be performed without requiring multiple levels of nested branch prediction logic to be evaluated in a single cycle. <IMAGE> |
