llvm/llvm-project

Funnel shift in 64-bit doesn't get matched to an intrinsic

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#138,334 opened on 2025年5月2日

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good first issuellvm:instcombine

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説明

Yes I know this has two cases of subpar optimization: One where the funnel shift is 64-bit based, and the other is left funnel shifts that can be converted to a right funnel shift. This one is about the latter. However, this was lifted from one of gcc's test suites.

https://godbolt.org/z/Yd63ed3sv

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