This article is a case study in the implementation of a portable, proven and efficient correctly rounded elementary function in double-precision. We describe the methodology used to achieve these goals in the crlibm library. There are two novel aspects to this approach. The first is the proof framework, and in general the techniques used to balance performance and provability. The second is the introduction of processor-specific optimization to get performance equivalent to the best current mathematical libraries, while trying to minimize the proof work. The implementation of the natural logarithm is detailed to illustrate these questions.
Mots clés : floating-point, elementary functions, logarithm, correct rounding
@article{ITA_2007__41_1_85_0, author = {Dinechin, Florent de and Lauter, Christoph and Muller, Jean-Michel}, title = {Fast and correctly rounded logarithms in double-precision}, journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications}, pages = {85--102}, publisher = {EDP-Sciences}, volume = {41}, number = {1}, year = {2007}, doi = {10.1051/ita:2007003}, mrnumber = {2330045}, zbl = {1132.65302}, language = {en}, url = {http://archive.numdam.org/articles/10.1051/ita:2007003/} }
TY - JOUR AU - Dinechin, Florent de AU - Lauter, Christoph AU - Muller, Jean-Michel TI - Fast and correctly rounded logarithms in double-precision JO - RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications PY - 2007 SP - 85 EP - 102 VL - 41 IS - 1 PB - EDP-Sciences UR - http://archive.numdam.org/articles/10.1051/ita:2007003/ DO - 10.1051/ita:2007003 LA - en ID - ITA_2007__41_1_85_0 ER -
%0 Journal Article %A Dinechin, Florent de %A Lauter, Christoph %A Muller, Jean-Michel %T Fast and correctly rounded logarithms in double-precision %J RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications %D 2007 %P 85-102 %V 41 %N 1 %I EDP-Sciences %U http://archive.numdam.org/articles/10.1051/ita:2007003/ %R 10.1051/ita:2007003 %G en %F ITA_2007__41_1_85_0
Dinechin, Florent de; Lauter, Christoph; Muller, Jean-Michel. Fast and correctly rounded logarithms in double-precision. RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 41 (2007) no. 1, pp. 85-102. doi : 10.1051/ita:2007003. http://archive.numdam.org/articles/10.1051/ita:2007003/
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