The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 09, 1999
Filed:
Jan. 13, 1997
Steven Michael Burchfiel, Cedar Park, TX (US);
Geoffrey Francis Burns, Macungie, PA (US);
James H Hesson, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A floating point arithmetic unit for performing independent multiply and add operations in the execution of a multiply-add instruction AC+B on three operands A, B, and C of p-bit precision includes a multiplier unit, a sticky collect unit, an adder unit, and a rounding unit. In addition, a risk condition detection unit provides detection of a risk condition corresponding to an occurrence of an imprecise resultant quantity prior to being rounded by the rounding unit. Upon detection of a risk condition, a trap is triggered and an extended sequence implementation unit carries out an extended multiply-add sequence and provides a multiply-add output having infinite precision prior to a final rounding. A floating point arithmetic method for performing independent multiply and add operations in the execution of a multiply-add instruction AC+B on three operands A, B, and C of p-bit precision is disclosed also.