[llvm] [X86][APX] Fix issues of suppressing APX for relocation (PR #139285)

[Feng Zou via llvm-commits]

fzou1 wrote:

> It looks to me like both 2) and 4) are caused due to we only changed the register class in MI but not in its use. Can we simply iterate all their uses and change to the same register class?

2) is not same issue as 4), and it's not related to the uses. The register class in operand 0 of instruction with relocation is updated to gr64_norex2_nosp but it's inflated by RA to GR64_NOSP.
`
%52:gr64_norex2_nosp = MOV64rm $rip, 1, $noreg, target-flags(x86-gotpcrel) @gvar, $noreg :: (load (s64) from got)
...
Inflated %52 to GR64_NOSP
...
`

But I agreed it's better to change norex2 register class in all the uses. Will update.

https://github.com/llvm/llvm-project/pull/139285