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Re: [PATCH v10 4/9] x86emul: disable FPU/MMX/SIMD insn emulation when !HVM



On 25/05/2020 15:27, Jan Beulich wrote:
> In a pure PV environment (the PV shim in particular) we don't really
> need emulation of all these. To limit #ifdef-ary utilize some of the
> CASE_*() macros we have, by providing variants expanding to
> (effectively) nothing (really a label, which in turn requires passing
> -Wno-unused-label to the compiler when build such configurations).
>
> Due to the mixture of macro and #ifdef use, the placement of some of
> the #ifdef-s is a little arbitrary.
>
> The resulting object file's .text is less than half the size of the
> original, and looks to also be compiling a little more quickly.
>
> This is meant as a first step; more parts can likely be disabled down
> the road.
>
> Suggested-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> ---
> v7: Integrate into this series. Re-base.
> ---
> I'll be happy to take suggestions allowing to avoid -Wno-unused-label.

I really would prefer the simplified version, which doesn't need
-Wno-unused-label at all.

I specifically don't see a need for these to be selected individually,
and a consequence of that is a vastly simplified patch.

However, to avoid this stalemate, Bregrudingly-acked-by: Andrew Cooper
<andrew.cooper3@xxxxxxxxxx> if you still insist on taking this route.



 


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