[Bug tree-optimization/99396] std::rotl and std::rotr Does not convert into ROTATE on the gimple level

[unlvsur at live dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99396

--- Comment #16 from cqwrteur <unlvsur at live dot com> ---
(In reply to Jakub Jelinek from comment #15)
> Could be if _GLIBCXX17_CONSTEXPR (...)
> sure.

bit header is a new C++20 header. There is no reason the compiler does not
support if constexpr.

If you compile it with pre-C++20, the code should even get compiled