[llvm] [AMDGPU][True16][CodeGen] atomic load/store i8 in true16 mode (PR #143044)

[Brox Chen via llvm-commits]

broxigarchen wrote:

> Do we have any tests that the hi/lo half that is unused by the instruction is reused by another instruction? I think for the non-atomic test cases we do, and these should work the same, but the atomic tests just don't cover that behavior.

Let me add a test

https://github.com/llvm/llvm-project/pull/143044