[PATCH] x86: Simplify AMX XSAVEC calculation logic.

[Sunil Pandey]

On Mon, Mar 31, 2025 at 9:25 PM Sunil Pandey <skpgkp2@gmail.com> wrote:

>
>
> On Mon, Mar 31, 2025 at 6:13 AM Florian Weimer <fweimer@redhat.com> wrote:
>
>> * Sunil K. Pandey:
>>
>> > +#ifdef __x86_64__
>> > +                   if (amx_flag)
>> > +                     {
>> > +                       unsigned int amx_size
>> > +                         = xstate_comp_offsets[18] +
>> xstate_comp_sizes[18];
>> > +                       _dl_x86_features_tlsdesc_state_size
>> > +                         = ALIGN_UP (amx_size +
>> TLSDESC_CALL_REGISTER_SAVE_AREA,
>> > +                                     64);
>> > +                     }
>> > +#endif
>>
>> I diskike the magic 18 (as the AMX bit number) appearing here.
>>
>> The logic for including and excluding states seems reversed to me.
>> Shouldn't we save and restore everything that we don't know anything
>> about, especially for the TLSDESC case?
>>
>> Thanks,
>> Florian
>>
>
> Thank you so much. Will submit v2.
>

v2 patch attached.
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