Method and system for efficiently mapping guest instruction in an emulation assist unit
US5742802A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1996 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Feb 16, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/45504
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides a method and system for using hardware to assist software in emulating the guest instructions. The method and system comprises an emulation assist unit (EAU) which efficiently maps a guest instruction to a unique tag, an index, and an address of the corresponding semantic routine. The index determines where in a cache a plurality of tags are stored. A separate cache within the EAU stores each tag in association with the address the first time the corresponding guest instruction is emulated. Thus, the emulation assist unit also dynamically responds to the set of guest instructions being emulated. The first time a guest instruction is emulated, the EAU determines the address and stores the address in the cache in association with the tag. When the guest instruction is emulated again, the EAU uses the tag to access the stored addresses of the corresponding semantic routine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.