[llvm] SROA generate a noundef instead of splatting a noundef int (PR #145122)

[Nikita Popov via llvm-commits]

nikic wrote:

The SROA tests can be found here: https://github.com/llvm/llvm-project/tree/main/llvm/test/Transforms/SROA You can either create a new file or try to find an existing one for this code path -- the easiest way to do that is to add an assert and see which tests fail :)

It's worth noting that we have another copy of the memset splat generation code here, using a different implementation: https://github.com/llvm/llvm-project/blob/437346378fd4d40af30e6969621a605cbd6215d1/llvm/lib/Transforms/Utils/VNCoercion.cpp#L415-L442 We should probably unify these as a followup.

https://github.com/llvm/llvm-project/pull/145122