High-Speed Double-Precision Computation of Reciprocal, Division, Square Root and Inverse Square Root

  title={High-Speed Double-Precision Computation of Reciprocal, Division, Square Root and Inverse Square Root},
  author={Jos{\'e}-Alejandro Pi{\~n}eiro and Javier D. Bruguera},
  journal={IEEE Trans. Computers},
A new method for the high-speed computation of double-precision floating-point reciprocal, division, square root, and inverse square root operations is presented in this paper. This method employs a second-degree minimax polynomial approximation to obtain an accurate initial estimate of the reciprocal and the inverse square root values, and then performs a modified Goldschmidt iteration. The high accuracy of the initial approximation allows us to obtain double-precision results by computing a… 

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