Instruction dependency scoreboard with a hierarchical structure
US6662293B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 2000 |
| Grant date | Dec 9, 2003 |
| Priority date | — |
| Expiry date | May 23, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3854
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
One embodiment of the present invention provides a system that selects instructions to be executed in a computer system that supports out-of-order execution of program instructions. The system receives dependency information for a first instruction. This dependency information identifies preceding instructions in the execution stream of a program that need to complete before the first instruction can be executed. The system divides this dependency information into a recent set and a less recent set. The recent set includes dependency information for a block of instructions immediately preceding the first instruction that need to complete before the first instruction can be executed. The less recent set includes dependency information for instructions not in the block of instructions immediately preceding the first instruction that need to complete before the first instruction can be executed. The system stores the recent set of dependency information in a first store, and stores the less recent set of dependency information in a second store. The first store is smaller and faster than the second store so that an update to dependency information takes less time to propagate through …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.