[llvm] [Scalarizer][DirectX] support structs return types (PR #111569)

[Farzon Lotfi via llvm-commits]

farzonl wrote:

@mariusz-sikora-at-amd  I wasn't aware of `uadd.with.overflow` when I added this feature. I feel like it should just be adding that intrinsic to `isTriviallyScalarizable ` and `isVectorIntrinsicWithStructReturnOverloadAtField`.

I'm a little suprised you are getting a casting error though. The only non dyn_casts are on `llvm/lib/Transforms/Scalar/Scalarizer.cpp:736` and `1087` and both check the vectors before that cast.



https://github.com/llvm/llvm-project/pull/111569