Don't reload length in String::push#155847
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Same as in Vec::push_mut, we get `.len()` once at the start since it won't change in the `reserve()` call. Saves reloading the length after the allocation: https://godbolt.org/z/W3G165Gd7
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No, these are the flags: |
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Works for me. I'm surprised the compiler doesn't see through it. @bors r+ |
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Don't reload length in String::push Same as in `Vec::push_mut`, we get `.len()` once at the start since it won't change in the `reserve()` call. Saves reloading the length after the allocation: https://godbolt.org/z/W3G165Gd7
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Don't reload length in String::push Same as in `Vec::push_mut`, we get `.len()` once at the start since it won't change in the `reserve()` call. Saves reloading the length after the allocation: https://godbolt.org/z/W3G165Gd7
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Rollup of 9 pull requests Successful merges: - #155381 (Fix a bug in `ChunkedBitSet::subtract`) - #155847 (Don't reload length in String::push) - #155858 (`slice::join`: borrow only once during length calc) - #155879 (enable pipe tests in Miri) - #155905 (Update LLVM to 22.1.4 (again)) - #155247 ([AIX] update linker default to bcdtors) - #155812 ([codex] tests: mark migrated UI tests as check-pass) - #155854 (Rename the diagnostic item for `std::sync::mpsc::Receiver`) - #155882 (Add regression test for #101363)
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Rollup merge of #155847 - DaniPopes:string-push-len, r=jhpratt Don't reload length in String::push Same as in `Vec::push_mut`, we get `.len()` once at the start since it won't change in the `reserve()` call. Saves reloading the length after the allocation: https://godbolt.org/z/W3G165Gd7
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Same as in
Vec::push_mut, we get.len()once at the start since it won't change in thereserve()call.Saves reloading the length after the allocation: https://godbolt.org/z/W3G165Gd7