[Bug target/111870] Miscompile of atomic rmw or on x86 (not aarch, though)

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111870

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
On aarch64, ldset does both a load and ior. that is unlike the `lock or` on
x86.