Patent · US Expired

Method and apparatus for producing correctly rounded values of functions using double precision operands

US6560623B1 · kind B1 · utility

21Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 16, 1999
Grant dateMay 6, 2003
Priority date
Expiry dateSep 16, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F7/556
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for finding the hard-to-round double precision operands x when processed by a function f(x)and using these hard-to-round numbers to optimize f(x) hardware and software f(x) algorithms to ensure proper rounding begins by segmenting all proper x operands into analysis domains (FIG. 8). The analysis domains are split into sub-domains (1202-1208) where a linear generator is used to generate candidate hard-to-find values for each sub-domain (1210). A quadratic filter is used to reduce the list of candidates to a final list of hard-to-round values for f(x) (1212). The hard-to-round double precision values are used to set a precision of hardware or software f(x) algorithm to ensure proper rounding or all valid x operations while simultaneously ensuring that too much precision, and therefore, reduced performance, is avoided.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.