tree 9dd2860a864b53c4cad56e4a29d5b3d8cc19a46d
parent 6ac06fe665d0101249a8f85691b738620efcfd02
author Michael Jones <michaelrj@google.com> 1630540265 +0000
committer Copybara-Service <copybara-worker@google.com> 1634598939 -0700

[libc] add atof, strtof and strtod

Add the string to floating point conversion functions.
Long doubles aren't supported yet, but floats and doubles are. The
primary algorithm used is the Eisel-Lemire ParseNumberF64 algorithm,
with the Simple Decimal Conversion algorithm as backup.

Links for more information on the algorithms:

Number Parsing at a Gigabyte per Second, Software: Practice and
Experience 51 (8), 2021 (https://arxiv.org/abs/2101.11408)
https://nigeltao.github.io/blog/2020/eisel-lemire.html
https://nigeltao.github.io/blog/2020/parse-number-f64-simple.html

Differential Revision: https://reviews.llvm.org/D109261

GitOrigin-RevId: 87c016078ad72c46505461e4ff8bfa04819fe7ba