Dan Gohman caf8bcceff Optimize Wtf8Buf::into_string for the case where it contains UTF-8. ... Add a `is_known_utf8` flag to `Wtf8Buf`, which tracks whether the string is known to contain UTF-8. This is efficiently computed in many common situations, such as when a `Wtf8Buf` is constructed from a `String` or `&str`, or with `Wtf8Buf::from_wide` which is already doing UTF-16 decoding and already checking for surrogates. This makes `OsString::into_string` O(1) rather than O(N) on Windows in common cases. And, it eliminates the need to scan through the string for surrogates in `Args::next` and `Vars::next`, because the strings are already being translated with `Wtf8Buf::from_wide`. Many things on Windows construct `OsString`s with `Wtf8Buf::from_wide`, such as `DirEntry::file_name` and `fs::read_link`, so with this patch, users of those functions can subsequently call `.into_string()` without paying for an extra scan through the string for surrogates.		2022-06-23 13:10:47 -07:00
..
benches	mv std libs to library/	2020-07-27 19:51:13 -05:00
primitive_docs	Add primitive documentation to libcore	2021-09-12 02:23:08 +00:00
src	Optimize Wtf8Buf::into_string for the case where it contains UTF-8.	2022-06-23 13:10:47 -07:00
tests	Fold aarch64 feature +fp into +neon	2022-03-22 15:14:33 -07:00
build.rs	Horizon OS STD support	2022-06-13 20:44:39 -07:00
Cargo.toml	library/std: Bump compiler_builtins	2022-05-26 21:11:16 +02:00