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Use bitwise XOR in to_ascii_uppercase This saves an instruction compared to the previous approach, which was to unset the fifth bit with bitwise OR. Comparison of generated assembly on x86: https://godbolt.org/z/GdfvdGs39 This can also affect autovectorization, saving SIMD instructions as well: https://godbolt.org/z/cnPcz75T9 Not sure if `u8::to_ascii_lowercase` should also be changed, since using bitwise OR for that function does not require an extra bitwise negate since the code is setting a bit rather than unsetting a bit. `char::to_ascii_uppercase` already uses XOR, so no change seems to be required there. |
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| .. | ||
| alloc | ||
| backtrace@b02ed04a7e | ||
| core | ||
| panic_abort | ||
| panic_unwind | ||
| portable-simd | ||
| proc_macro | ||
| profiler_builtins | ||
| rtstartup | ||
| rustc-std-workspace-alloc | ||
| rustc-std-workspace-core | ||
| rustc-std-workspace-std | ||
| std | ||
| stdarch@bcbe010614 | ||
| test | ||
| unwind | ||