[Bug target/119210] [SME] 'smstart za' seems not to dominate the block that uses za register

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119210

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So:
        mrs     x16, tpidr2_el0
        cbnz    x16, .L22  <== it will branch to .L22, and miss 'smstart za'
        mov     x0, x3
        smstart za
        bl      __arm_tpidr2_restore
.L22:


This means it is already started.


What kernel version are you using? Could this be a bug in the kernel not
saving/restoring tpidr2_el0 correctly or setting tpidr2_el0 to zero originally.