Methods for safe and efficient implementations of virtual machines
US5761477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1995 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Dec 4, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/3624
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An efficient method for implementing a safe virtual machine, in software, that embodies a general purpose memory protection model. The present invention runs on any general purpose computer architecture and will run an executable that has been developed for the virtual machine. The present invention compiles the executable into the native instructions of the hardware. During the compilation, specialized code sequences are added to the code using a technique called software fault isolation. A set of allowed behaviors and a set of responses to the undesirable actions will be created and written to memory. A series of optimizations are applied so that the translated code executes at nearly the native speed of the architecture, but the fault isolation sequences prevent it from engaging in undesirable actions. In particular, the memory protection model is enforced, providing the same level of protection that customarily requires hardware support to enforce efficiently.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.