Method and apparatus for performing multiplicative functions
US8838663B2 · kind B2 · utility
11Cited by
4References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 30, 2007 |
| Grant date | Sep 16, 2014 |
| Priority date | — |
| Expiry date | Dec 11, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2207/5356
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A new function for calculating the reciprocal residual of a floating-point number X is defined as recip_residual(X)=1−X*recip(X), where recip(X) represents the reciprocal of X. The function may be implemented using a fused multiply-add unit in a processor. The reciprocal value of X, recip(X), may be obtained from a lookup table. The recip_residual function may help reduce the latency of many multiplicative functions that are based on products of multiple numbers and can be expressed in simple terms of functions on each individual number (e.g., log(U*V)=log(U)+log(V)).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.