Processing unit having decimal floating-point divider using...

Details Processing unit having decimal floating-point divider using... Processing unit having decimal floating-point divider using...

2004-11-05

2008-12-16

Malzahn, David H (Department: 2193)

Electrical computers: arithmetic processing and calculating

Electrical digital calculating computer

Particular function performed

Reexamination Certificate

active

07467174

ABSTRACT:
A decimal floating-point divider is described that implements efficient hardware-based techniques for performing decimal floating-point division. The divider uses an accurate piecewise linear approximation to obtain an initial estimate of a divisor's reciprocal. The divider improves the initial estimate of the divisor's reciprocal using a modified form of Newton-Raphson iteration. The divider multiplies the estimated divisor's reciprocal by the dividend to produce a preliminary quotient. The preliminary quotient is rounded to produce the final decimal floating-point quotient.

REFERENCES:
patent: 3591786 (1971-07-01), Nelson
patent: 4635220 (1987-01-01), Yabe et al.
patent: 4692891 (1987-09-01), Yamaoka et al.
patent: 4817048 (1989-03-01), Rawlinson et al.
patent: 4999801 (1991-03-01), Katsuno
patent: 5515308 (1996-05-01), Karp et al.
patent: 5587940 (1996-12-01), Ferguson
patent: 6067617 (2000-05-01), Webb et al.
patent: 6769006 (2004-07-01), Krouglov et al.
patent: 7127483 (2006-10-01), Beaumont-Smith et al.
patent: 2002/0143840 (2002-10-01), Krouglov et al.
patent: 2004/0167956 (2004-08-01), Vihriala
Liang-KaiWang et al., “Decimal Floating-Point Division Using Newton-Raphson Iteration,” Proceedings of the 15th IEEE International Conference on Application-Specific Systems, Architectures and Processors (ASAP'04), IEEE Computer Society Press, Sep. 2004, pp. 84-95.
Michael F. Cowlishaw, “Decimal Arithmetic FAQ: Part 1—General Questions,” IBM Corporation, http://www2.hursley.ibm.com/decimal/decifaq1.html, Nov. 27, 2003, 7 pages.
Michael F. Cowlishaw, “Decimal Floating-Point: Algorism for Computers,” Proceedings of the 16thIEEE Symposium on Computer Arithmetic (ARITH '03), 2003, pp. 104-111.
Draft IEEE Standard for Floating-Point Arithmetic P754/D0.10.9, Apr. 6, 2005, http://754r.ucbtest.org/drafts/754r.pdf, 136 pages.
Fadi Y. Busaba et al., “The IBM z900 Decimal Arithmetic Unit,” Proceedings of the 35thAsilomar Conference on Signals, Systems and Computers, vol. 2, IEEE Computer Society, Nov. 2001, pp. 1335-1339.
Michael F. Cowlishaw, “A Summary of Densely Packed Decimal Encoding,” IEEE Proceedings—Computers and Digital Techniques ISSN 1350-2387, vol. 149, No. 3, pp. 102-104, May 2002. http://www2.hursley.ibm.com/decimal/DPDecimal.html.
Naofumi Takagi, “Powering by a Table Look-up and a Multiplication with Operand Modification,” IEEE Transactions on Computers, vol. 47, No. 11, Nov. 1998, pp. 1216-1222.
Stuart F. Oberman et al., “Division Algorithms and Implementations,” IEEE Transactions on Computers, vol. 46, No. 8, Aug. 1997, pp. 833-854.
Stuart F. Oberman et al., “An Analysis of Division Algorithms and Implementations,” Technical Report: CSL-TR-95-675, Stanford University, Jul. 1995, pp. 1-51.
Eric M. Schwarz, “Rounding for Quadratically Converging Algorithms for Division and Square Root,” Proceedings of the 29thAsilomar Conference on Signals, Systems and Computers, IEEE Computer Society, 1995, pp. 600-603.
Mark A. Erle et al., “Decimal Multiplication Via Carry-save Addition,” Proceedings of IEEE International Conference on Application-Specific Systems, Architectures, and Processors, 2003, pp. 337-347.
David L. Chaum, “Untraceable Electronic Mail, Return Addresses, and Digital Pseudonyms,” Communications of the ACM, vol. 24, No. 2, Feb. 1981, pp. 84-88.

Affiliated with

Also associated with

Rating

Processing unit having decimal floating-point divider using... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Processing unit having decimal floating-point divider using..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Processing unit having decimal floating-point divider using... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-4034364