Patent · US Expired

Rounding anticipator for floating point operations

US6557021B1 · kind B1 · utility

13Cited by
7References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 17, 2000
Grant dateApr 29, 2003
Priority date
Expiry dateMar 17, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F7/5443
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus that performs anticipatory rounding of intermediate results in a floating point arithmetic system while the intermediate results are being normalized is disclosed. One embodiment of the present invention includes four logic levels, implemented in N-NARY logic. In the first three logic levels, propagation information is gathered for preselected bit groups from the coarse and medium shift output of the normalizer as those results become available. In the fourth level, an incremented, normalized intermediate single-precision or double-precision mantissa result is produced by combining fine shift output bit values with propagation information for the appropriate top bit group, middle bit group, and bottom bit group. The appropriate bit groups are determined by examining the value of the fine shift select signal.

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