Re: [PATCH v2 -tip] x86/percpu: Use C for arch_raw_cpu_ptr()

[Linus Torvalds]

On Thu, 19 Oct 2023 at 11:16, Uros Bizjak <ubizjak@xxxxxxxxx> wrote:
>
> And NO (whee...), there is no rematerialization of asm (foo() ). OTOH,
> there is also no rematerialization from non-volatile memory (bar() ),
> although it would be more optimal than spill to/fill from a frame pair
> of moves. I wonder what are "certain circumstances" that the
> documentation is referring to.

Honestly, I've actually never seen gcc rematerialize anything at all.

I really only started worrying about remat issues in a theoretical
sense, and because I feel it would be relatively *easy* to do for
something where the source is a load.

              Linus