Resynchronization of a superscalar processor
US5764938A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1997 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Feb 10, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3885
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Operations of a pipeline processor (110) are resynchronized under designated conditions. The processor updates a fetch program counter (210) and, as directed by the counter, fetches instructions from a memory (114). The processor concurrently dispatches, in the fetched order, multiple instructions to designated functional units (170, 171, 172, 173, 174 and 175). Dispatched instructions are queued in functional unit reservation stations. Result entries corresponding to the queued instructions are allocated in a reorder buffer 126 queue in their order of dispatch. Instructions are executed out of their fetched order and results are entered in the allocated result entries when execution is complete. Allocated result entries at the head of the reorder buffer queue are retired and an instruction pointer (620) is updated. The processor is resynchronized when it detects a resynchronization condition and acknowledges the resynchronization condition in the allocated result entry corresponding to the instruction that detected the condition. When the reorder buffer entry holding the resynchronization acknowledgement is retired, the processor flushes the reorder buffer and the reservation stat…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.