use is_multiple_of and div_ceil
#143477
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use is_multiple_of and div_ceil
#143477
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Portable SIMD is developed in its own repository. If possible, consider making this change to rust-lang/portable-simd instead. cc @calebzulawski, @programmerjake Some changes occurred to the CTFE machinery Some changes occurred to the CTFE / Miri interpreter cc @rust-lang/miri |
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@bors r+ rollup |
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Rollup of 6 pull requests Successful merges: - #143416 (mbe: Defer checks for `compile_error!` until reporting an unused macro rule) - #143470 (std: sys: net: uefi: tcp4: Implement read) - #143477 (use `is_multiple_of` and `div_ceil`) - #143484 (distinguish the duplicate item of rpitit) - #143493 (tidy: use --bless for tidy spellcheck instead of spellcheck:fix) - #143504 (compiletest: print slightly more information on fs::write failure) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #143477 - folkertdev:use-is-multiple-of, r=joshtriplett use `is_multiple_of` and `div_ceil` In tricky logic, these functions are much more informative than the manual implementations. They also catch subtle bugs: - the manual `is_multiple_of` often does not handle division by zero - manual `div_ceil` often does not consider overflow The transformation is free for `is_multiple_of` if the divisor is compile-time known to be non-zero. For `div_ceil` there is a small cost to considering overflow. Here is some assembly https://godbolt.org/z/5zP8KaE1d.
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In tricky logic, these functions are much more informative than the manual implementations. They also catch subtle bugs:
is_multiple_ofoften does not handle division by zerodiv_ceiloften does not consider overflowThe transformation is free for
is_multiple_ofif the divisor is compile-time known to be non-zero. Fordiv_ceilthere is a small cost to considering overflow. Here is some assembly https://godbolt.org/z/5zP8KaE1d.