Radix tree search logic
US5873078A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1996 |
| Grant date | Feb 16, 1999 |
| Priority date | — |
| Expiry date | Jul 19, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99943
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a search method for a radix search tree, a logic circuit for computing the actual offset of an entry in a node in a tree. The logic circuit accepts a pointer to a node in the tree, along with an associated bit mask indicating which entries are present in the node. The logic circuit further receives an entry value, the offset of which from the beginning of the node is to be computed by the logic circuit. The logic circuit utilizes Boolean AND gates to mask off higher order bits in the bit mask above the bit position corresponding to the entry value received by the logic circuit. The lower order bits in the bit mask, up to but not including the bit position corresponding to the entry value, are added together to determine the number of entries that exist at a lower offset in the node than the entry indicated by the entry value. The logic circuit combines the pointer received with the sum computed to calculate the offset memory address at which the entry is located in the node.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.