[llvm] CodeGen/test: improve a test, regen with UTC (PR #113338)

[Artem Belevich via llvm-commits]

https://github.com/Artem-B commented:

I like the idea of testing individual instructions separately and using automatic check generation.

The only question is whether the tests could be trimmed down further to reduce the amount of code in-between the loads/stores.

https://github.com/llvm/llvm-project/pull/113338