General purpose use of a stack pointer register
US5634046A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1994 |
| Grant date | May 27, 1997 |
| Priority date | — |
| Expiry date | Sep 30, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3013
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The stack pointer register in a computer is made available for general purpose use by programs executing at lower privilege levels than interrupt handlers. A set of instructions in such programs, excluding stack operations, stores data other than the stack pointer, such as operands, and the like, in the stack pointer register. When switching execution to an interrupt handler on an interrupt, return address data for the currently executing program is pushed onto a stack at the interrupt handler's privilege level. Thus, storing other data in the stack pointer register does not result in stack corruption. Also, these instructions can store data in a scratch portion of a stack segment beyond the current stack pointer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.