[llvm] [SROA] Allow `llvm.launder.invariant.group` intrinsic to be splittable (PR #72056)

[Antonio Frighetto via llvm-commits]

antoniofrighetto wrote:

Not exactly sure if the optimized IR of `partial_use_of_struct` test is what we want.

https://github.com/llvm/llvm-project/pull/72056