Reduced size storage apparatus for storing cache-line-related data in a high frequency microprocessor
US6016545A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1997 |
| Grant date | Jan 18, 2000 |
| Priority date | — |
| Expiry date | Dec 16, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3844
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A microprocessor stores cache-line-related data (e.g. branch predictions or predecode data, in the illustrated embodiments) in a storage which includes fewer storage locations than the number of cache lines in the instruction cache. Each storage location in the storage is mappable to multiple cache lines, any one of which can be associated with the data stored in the storage location. The storage may thereby be smaller than a storage which provides an equal number of storage locations as the number of cache lines in the instruction cache. Access time to the storage may be reduced, therefore providing for a higher frequency implementation. Still further, semiconductor substrate area occupied by the storage may be decreased. In one embodiment, the storage is indexed by a subset of the index bits used to index the instruction cache. The subset comprises the least significant bits of the cache index. In other words, the cache lines which share a particular storage location within the storage differ in the most significant cache index bits. Therefore, code which exhibits spatial locality may experience little conflict for the storage locations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.