Towards a correctly-rounded and fast power function in binary64 arithmetic
Résumé
We design algorithms for the correct rounding
of the power function $x^y$ in the binary64 IEEE 754 format,
for all rounding modes, modulo the knowledge of hardest-to-
round cases. Our implementation of these algorithms largely
outperforms previous correctly-rounded implementations and is
not far from the efficiency of current mathematical libraries,
which are not correctly-rounded. Still, we expect our algorithms
can be further improved for speed. The proofs of correctness
are fully detailed in an extended version of this paper, with
the goal to enable a formal proof of these algorithms. We hope
this work will motivate the next IEEE 754 revision committee to
require correct rounding for mathematical functions.
Domaines
Informatique [cs]Origine | Fichiers produits par l'(les) auteur(s) |
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