Optimization of range checking
US4642765A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1985 |
| Grant date | Feb 10, 1987 |
| Priority date | — |
| Expiry date | Apr 15, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F8/443
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method operable within an optimizing compiler to move certain range check instructions out of single entry strongly connected regions or loops and into linear regions of the instruction stream whereby computational efficiency is increased with no loss of program accuracy. The method comprises placing a range check trap instruction into the header node of the SCR provided there is only one conditional exit from the SCR, modifying the conditional exit test based on the value of the induction variable v, and inserting a new check at the loop exit point(s) to insure that the induction variable has reached the value it would have obtained in the original (unmodified) program.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.