Floating point division and square root algorithms and implementation in the AMD-K7/sup TM/ microprocessor

This paper presents the AMD-K7 IEEE 754 and /spl times/87 compliant floating point division and square root algorithms and implementation. The AMD-K7 processor employs an iterative implementation of a series expansion to converge quadratically to the quotient and square root. Highly accurate initial approximations and a high performance shared floating point multiplier assist in achieving low division and square root latencies at high operating frequencies. A novel time-sharing technique allows independent floating point multiplication operations to proceed while division or square root computation is in progress. Exact IEEE 754 rounding for all rounding modes and target precisions has been verified by conventional directed and random testing procedures, along with the formulation of a mechanically-checked formal proof using the ACL2 theorem prover.

[1]  Stuart Franklin Oberman,et al.  Design issues in high performance floating point arithmetic units , 1996 .

[2]  Robert E Goldschmidt,et al.  Applications of division by convergence , 1964 .

[3]  Fred Weber,et al.  AMD 3DNow! technology: architecture and implementations , 1999, IEEE Micro.

[4]  Robert S. Boyer,et al.  A computational logic handbook , 1979, Perspectives in computing.

[5]  Michael J. Flynn On Division by Functional Iteration , 1970, IEEE Transactions on Computers.

[6]  Debjit Das Sarma,et al.  Faithful bipartite ROM reciprocal tables , 1995, Proceedings of the 12th Symposium on Computer Arithmetic.

[7]  Andrew D. Booth,et al.  A SIGNED BINARY MULTIPLICATION TECHNIQUE , 1951 .

[8]  F. Weber,et al.  An out-of-order three-way superscalar multimedia floating-point unit , 1999, 1999 IEEE International Solid-State Circuits Conference. Digest of Technical Papers. ISSCC. First Edition (Cat. No.99CH36278).

[9]  Michael J. Flynn,et al.  Design Issues in Division and Other Floating-Point Operations , 1997, IEEE Trans. Computers.

[10]  Jordi Cortadella,et al.  Evaluation of A + B = K Conditions Without Carry Propagation , 1992, IEEE Trans. Computers.