发明名称 |
Apparatus and method for efficient loop control in a superscalar microprocessor |
摘要 |
A superscalar microprocessor implements a repeated string instruction by putting the microcode unit in a continuous loop. The microcode sequence that implements the repeated string operation includes a conditional-exit instruction rather than a conditional branch and decrement microcode instruction. A conditional-exit instruction decrements a loop count value and conveys a termination signal to a microcode unit when a termination condition is detected. Because several iterations of the instructions that implement the string instruction may be dispatched before the conditional-exit instruction is evaluated, the additional iterations of the microcode loop are canceled. By eliminating the conditional branch and decrement microcode instruction, a loop iteration may be executed in a single clock cycle by three functional units. |
申请公布号 |
US6032252(A) |
申请公布日期 |
2000.02.29 |
申请号 |
US19970959631 |
申请日期 |
1997.10.28 |
申请人 |
ADVANCED MICRO DEVICES, INC. |
发明人 |
PETRO, ANTHONY M.;MCMINN, BRIAN D. |
分类号 |
G06F9/308;G06F9/32;G06F9/38;(IPC1-7):G06F9/38;G06F9/40 |
主分类号 |
G06F9/308 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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