Patent · US Expired

Multiply-add operating device for floating point number

US6363476B1 · kind B1 · utility

12Cited by
6References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 11, 1999
Grant dateMar 26, 2002
Priority date
Expiry dateAug 11, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F7/483
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A floating point multiply-add operating device in which a critical path in an addition process of continuous multiply-add operations of floating point numbers is shortened to improve operation efficiency is disclosed. This operating device includes: an exponent operating section for comparing an exponent of a floating point number of an operation result of a preceding multiply-add operation n with an exponent of a multiplication result of a subsequent multiply-add operation (n+1), and calculating an alignment shift count of the multiply-add operation (n+1) by the comparison result; and a mantissa operating section for aligning one mantissa of mantissas of two operands according to the alignment shift count inputted from the exponent operating section, calculating a sum of an aligned mantissa of the operand and the mantissa of the other operand, and normalizing a calculated addition result of the mantissas as needed, thereby calculating a mantissa of the multiply-add operation (n+1). The alignment shift count is obtained by starting calculation of an alignment shift count of the subsequent multiply-add operation (n+1) before normalization of the preceding multiply-add operation n is…

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