Uh oh!
There was an error while loading. Please reload this page.
Make some usize-typed masks definitions agnostic to the size of usize - #96081
Merged
Conversation
Some masks where defined as ```rust const NONASCII_MASK: usize = 0x80808080_80808080u64 as usize; ``` where it was assumed that `usize` is never wider than 64, which is currently true. To make those constants valid in a hypothetical 128-bit target, these constants have been redefined in an `usize`-width-agnostic way ```rust const NONASCII_MASK: usize = usize::from_ne_bytes([0x80; size_of::<usize>()]); ``` There are already some cases where Rust anticipates the possibility of supporting 128-bit targets, such as not implementing `From<usize>` for `u64`.
rust-highfive
commented
Apr 15, 2022
Contributor
Hey! It looks like you've submitted a new PR for the library teams! If this PR contains changes to any Examples of
|
rust-highfive
commented
Apr 15, 2022
Contributor
r? @yaahc (rust-highfive has picked a reviewer for you, use r? to override) |
usize-typed masks definition agnostic to the size of usizeusize-typed masks definitions agnostic to the size of usizeyaahc
commented
Apr 15, 2022
Member
Sounds good and looks great, thank you for the PR! @bors r+ |
bors
commented
Apr 15, 2022
Collaborator
📌 Commit 93ae6f8 has been approved by |
| #[inline] | ||
| fn contains_nonascii(v: usize) -> bool { | ||
| const NONASCII_MASK: usize = 0x80808080_80808080u64 as usize; | ||
| const NONASCII_MASK: usize = usize::from_ne_bytes([0x80; core::mem::size_of::<usize>()]); |
Member
There was a problem hiding this comment.
Why doesn't this use usize::repeat_u8?
EDIT: Oh, I guess that is crate-private.
bors added a commit
to rust-lang-ci/rust
that referenced
this pull request
Apr 16, 2022
Rollup of 7 pull requests Successful merges: - rust-lang#95887 (resolve: Create dummy bindings for all unresolved imports) - rust-lang#96023 (couple of clippy::perf fixes) - rust-lang#96035 (Update GitHub Actions actions/checkout Version v2 -> v3) - rust-lang#96038 (docs: add link from zip to unzip) - rust-lang#96047 (:arrow_up: rust-analyzer) - rust-lang#96059 (clarify doc(cfg) wording) - rust-lang#96081 (Make some `usize`-typed masks definitions agnostic to the size of `usize`) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment
6 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Some masks where defined as
where it was assumed that
usizeis never wider than 64, which is currently true.To make those constants valid in a hypothetical 128-bit target, these constants have been redefined in an
usize-width-agnostic wayThere are already some cases where Rust anticipates the possibility of supporting 128-bit targets, such as not implementing
From<usize>foru64.