Data processor with programmable levels of speculative instruction
fetching and method of operation
    1.
    发明授权
    Data processor with programmable levels of speculative instruction fetching and method of operation 失效
    数据处理器具有可编程级别的推测指令提取和操作方法

    公开(公告)号:US5553255A

    公开(公告)日:1996-09-03

    申请号:US429439

    申请日:1995-04-27

    IPC分类号: G06F9/38

    摘要: A data processor (12) has a branch prediction unit (28) that predicts conditional branch instructions and a control unit (70) therein that monitors the number of unresolved branch instructions. This control unit selectively allows the data processor to fetch the instructions indicated by the branch prediction unit from an external memory system depending upon the number of unresolved branch instructions. The particular threshold number of unresolved branch instructions is user programmable. The data processor thereby limits its bus accesses to those occasions when it is reasonably sure that it will need the indicated instructions.

    摘要翻译: 数据处理器(12)具有预测条件分支指令的分支预测单元(28)和其中监视未解决的分支指令的数量的控制单元(70)。 该控制单元选择性地允许数据处理器根据未解决的分支指令的数量从外部存储器系统取出由分支预测单元指示的指令。 未解决的分支指令的特定阈值数量是用户可编程的。 因此,当合理确定需要指示的指令时,数据处理器将其总线访问限制在那些场合。