cowrcstr: Move owned variant drop out of line. - #451
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This reduces the amount of drop glue that the compiler emits for each token significantly, and the owned variant is supposed to be rare already (escaped strings and such). It'd be better to somehow coalesce the drop of all the variants because there's at most one CowRcStr per token, but it's annoying to do so without changing the shape of Token as a whole / the ergonomics of the library. This still gives a good targeted win.
emilio
enabled auto-merge
August 30, 2026 14:06
mrobinson
approved these changes
Aug 30, 2026
| #[cold] | ||
| #[inline(never)] | ||
| unsafe fn drop_slow(ptr: *const String) { | ||
| mem::drop(Rc::from_raw(ptr)) |
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I would surround this with unsafe, to avoid a warning on some versions of Rust.
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| mem::drop(Rc::from_raw(ptr)) | |
| unsafe { mem::drop(Rc::from_raw(ptr)) }; |
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Gah, sorry, the auto-merge stuff. Will do :(
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Though IIRC I tested this with nightly and it didn't warn, is it edition dependent or something?
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This reduces the amount of drop glue that the compiler emits for each token significantly, and the owned variant is supposed to be rare already (escaped strings and such).
It'd be better to somehow coalesce the drop of all the variants because there's at most one CowRcStr per token, but it's annoying to do so without changing the shape of Token as a whole / the ergonomics of the library. This still gives a good targeted win.