Instruction prefetch system for conditional branch instruction for
central processor unit
    1.
    发明授权
    Instruction prefetch system for conditional branch instruction for central processor unit 失效
    用于中央处理器单元的条件分支指令的指令预取系统

    公开(公告)号:US4742451A

    公开(公告)日:1988-05-03

    申请号:US612621

    申请日:1984-05-21

    IPC分类号: G06F9/38 G06F9/42

    CPC分类号: G06F9/3804

    摘要: A central processor unit for a digital data processing system that processes prefetched instructions including a conditional branch instruction. The processor includes a fetch unit that has separate portions, one that retrieves operands and the other that retrieves instructions. When the fetch unit fetches a conditional branch instruction, it may continue to prefetch "branch not taken" instructions using the instruction fetch portion. The fetch unit initially uses the operand fetch portion to prefetch "branch taken" instructions. If it is determined that the branch is not taken, the prefetch operation is aborted, otherwise the prefetch operation is allowed to continue to provide the next instruction used by the processor.

    摘要翻译: 一种用于数字数据处理系统的中央处理器单元,用于处理包括条件分支指令的预取指令。 处理器包括具有单独部分的提取单元,一个检索操作数,另一个检索指令。 当提取单元获取条件分支指令时,可以使用指令获取部分继续预取“分支未采取”指令。 提取单元最初使用操作数获取部分预取“分支取出”指令。 如果确定不采用分支,则预取操作被中止,否则允许预取操作继续提供处理器使用的下一条指令。