Counting speculative and non-speculative events
US6675372B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 31, 2000 |
| Grant date | Jan 6, 2004 |
| Priority date | — |
| Expiry date | May 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3854
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Counting events during the execution of one or more instructions in a computer system may be accomplished by maintaining a non-speculative counter for counting events occurring in non-speculative instructions, as well as a separate speculative counter for counting events occurring in speculative instructions. Event counters may be used to count individual events occurring during the processing of instructions. When the instruction has been completed, the amount in the event counter corresponding to a particular event for that instruction is added to the amount in the speculative counter corresponding to the event. Then, any retirable instructions are retired. Once an instruction is retired, it is no longer speculative, allowing the amount in the speculative counter to be decremented and the amount in the non-speculative counter to be incremented by the amount in any event counters corresponding to retirable instructions. The speculative and non-speculative counters may then be examined at any point in time to give a clear picture of the number of times a specific event has occurred, even when instructions are executed out-of-order.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.