Apparatus and method for emulation routine pointer prefetch
US5574887A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 20, 1993 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Sep 20, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3017
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for emulation routine pointer prefetch are disclosed. The apparatus includes an emulated program counter (EPC), a prefetch state machine, a summing device, an opcode storage device, and a pointer storage device. The EPC, opcode storage device and pointer storage device are coupled to a bus to receive, store and output an emulated program counter value, an opcode value and a pointer to a next emulation routine. The EPC, opcode storage device, and pointer storage device are controlled by the prefetch state machine, which also is coupled to the bus to detect a reference to a reserved memory address and stores an updated emulated program counter value in the EPC using the summing device. The prefetch state machine uses the EPC value to prefetch the next source instruction to be emulated in a first memory operation. A portion of the prefetched source instruction is the opcode value and is stored in the opcode storage device. The prefetch state machine uses the opcode value in a second memory operation to retrieve a pointer to a corresponding emulation routine which is stored in the pointer storage device. The method for emulation routine pointer prefetch preferab…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.