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From: "unlvsur at live dot com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/99396] std::rotl and std::rotr Does not
 convert into ROTATE on the gimple level
Date: Fri, 05 Mar 2021 02:08:29 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99396

--- Comment #2 from cqwrteur <unlvsur at live dot com> ---
(In reply to Andrew Pinski from comment #1)
>     return std::rotr(v,((unsigned int)t)&63);
> Fixes the problem ....
>     int a =3D std::abs(t);
>     a &=3D 63;
>     return std::rotr(v,a);
>=20
> Also improves the situtation.
> I am thinking the std::rotr could be rewritten or we could optimize this =
at
> the tree level into the almost the intrinsics.
> Note I think I Might have gotten the above incorrect a little bit.

I would like to see __builtin_cpp_rotl and __builtin_cpp_rotr to allow more
aggressive optimizations since rotl and rotr are so important for cryptogra=
phy.=