Make some usize-typed masks definitions agnostic to the size of usize
#96081
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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`.
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usize-typed masks definition agnostic to the size of usizeusize-typed masks definitions agnostic to the size of usize
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Sounds good and looks great, thank you for the PR! @bors r+ |
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| @@ -77,6 +77,6 @@ fn is_ascii_align_to_unrolled(bytes: &[u8]) -> bool { | |||
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| #[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>()]); | |||
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Why doesn't this use usize::repeat_u8?
EDIT: Oh, I guess that is crate-private.
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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
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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.