tree e630a6f6b731c1480b52b2b4139179c274e8dcaa
parent dd928bee395be355d64e4968fefaa41feec193f9
author Michael Jones <michaelrj@google.com> 1635291563 -0700
committer Copybara-Service <copybara-worker@google.com> 1635530171 -0700

[libc] add fast path to string to float conversion

Add the fast path first described by Clinger [1] with additions by Gay [2].
This speeds up conversion by about 10% by handling numbers with fewer digits
more efficiently.

[1] Clinger WD. How to Read Floating Point Numbers Accurately.
SIGPLAN Not 1990 Jun;25(6):92–101. https://doi.org/10.1145/93548.93557.
[2] Gay DM, Correctly rounded binary-decimal and decimal-binary conversions;
1990. AT&T Bell Laboratories Numerical Analysis Manuscript 90-10.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D112580

GitOrigin-RevId: 62c187cb55897e3732667892d38bb9490eb2b669