发明名称 |
STORE TO LOAD FORWARDING PREDICTOR WITH UNTRAINING |
摘要 |
<p>A processor employs a store to load forward (STLF) predictor which may indicate, for dispatching loads, a dependency on a store. The dependency is indicated for a store which, during a previous execution, interfered with the execution of the load. Since a dependency is indicated on the store, the load is prevented from scheduling and/or executing prior to the store. The STLF predictor is trained with information for a particular load and store in response to executing the load and store and detecting the interference. Additionally, the STLF predictor may be untrained (e.g. information for a particular load and store may be deleted) if a load is indicated by the STLF predictor as dependent upon a particular store and the dependency does not actually occur. In one implementation, the STLF predictor records at least a portion of the PC of a store which interferes with the load in a first table indexed by the load PC. A second table maintains a corresponding portion of the store PCs of recently dispatched stores, along with tags identifying the recently dispatched stores. In another implementation, the STLF predictor records a difference between the tags assigned to a load and a store which interferes with the load in a first table indexed by the load PC. The PC of the dispatching load is used to select a difference from the table, and the difference is added to the tag assigned to the load.</p> |
申请公布号 |
EP1244961(B1) |
申请公布日期 |
2004.03.17 |
申请号 |
EP20000951015 |
申请日期 |
2000.08.08 |
申请人 |
ADVANCED MICRO DEVICES INC. |
发明人 |
KELLER, JAMES, B.;GREEN, THOMAS, S.;LIEN, WEI-HAN;HADDAD, RAMSEY, W. |
分类号 |
G06F9/38;(IPC1-7):G06F9/38 |
主分类号 |
G06F9/38 |
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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