Leading zero estimation modification for unfused rounding catastrophic cancellation
US8239441B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 15, 2008 |
| Grant date | Aug 7, 2012 |
| Priority date | — |
| Expiry date | Jun 8, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/5443
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Modifying a leading zero estimation during an unfused multiply add operation of (A*B)+C. A plurality of terms x and y may be received, and each may be based on truncated terms s and t (e.g., in performing the unfused multiply add operation) and the shifted C term. A first leading zero estimation may be calculated based on the terms x and y. It may be determined if near total catastrophic cancellation has occurred. A carry in from a right most number of bits of the terms s and t and the most significant truncated bits of s and t may be used to generate a second leading zero estimation based on the first leading zero estimation if the near total catastrophic cancellation has occurred.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.