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

[jakub at gcc dot gnu.org via Gcc-bugs]

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

--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I believe std::__rot{l,r} can be used even in C++14 and if constexpr is only
supported in C++17 and later.
With optimizations enabled (_Nd & (_Nd - 1)) == 0 will optimize into constant
anyway.