首页> 外国专利> AVOIDING REGISTER READ-AFTER-WRITE HAZARDS AFTER SPECULATIVE EXECUTION

AVOIDING REGISTER READ-AFTER-WRITE HAZARDS AFTER SPECULATIVE EXECUTION

机译:在执行程序后避免寄存器读后写危害

摘要

One embodiment of the present invention provides a system that avoids register read-after-write (RAW) hazards upon returning from a speculative-execution mode. This system operates within a processor with an in-order architecture, wherein the processor includes a short-latency scoreboard that delays issuance of instructions that depend upon uncompleted short-latency instructions. During operation, the system issues instructions for execution in program order during execution of a program in a normal-execution mode. Upon encountering a condition (a launch condition) during an instruction (a launch-point instruction), which causes the processor to enter the speculative-execution mode, the system generates a checkpoint that can subsequently be used to return execution of the program to the launch-point instruction, and commences execution in the speculative-execution mode. Upon encountering a condition that causes the processor to leave the speculative-execution mode and return to the launch-point instruction, the system uses the checkpoint to resume execution in the normal-execution mode from the launch-point instruction. In doing so, the system ensures that entries. that were in the short-latency scoreboard prior to entering the speculative-execution mode, and which are not yet resolved, are accounted for in order to prevent register RAW hazard when resuming execution from the launch-point instruction.
机译:本发明的一个实施例提供了一种在从推测执行模式返回时避免寄存器写后读(RAW)危险的系统。该系统在具有顺序架构的处理器内操作,其中处理器包括短时延记分板,该短时延记分板延迟取决于未完成的短时延指令的指令的发布。在操作期间,系统在正常执行模式下在程序执行期间发出以程序顺序执行的指令。在指令(启动点指令)期间遇到条件(启动条件),该条件导致处理器进入推测执行模式时,系统会生成一个检查点,该检查点随后可用于将程序的执行返回给处理器。启动点指令,并以推测执行模式开始执行。在遇到导致处理器退出推测执行模式并返回到启动点指令的条件时,系统使用检查点从启动点指令以正常执行模式恢复执行。这样做时,系统确保输入。进入推测执行模式之前已在短等待时间记分板上并且尚未解决的问题要考虑在内,以防止在从启动点指令恢复执行时发生寄存器RAW危险。

著录项

相似文献

  • 专利
  • 外文文献
  • 中文文献
获取专利

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号