[llvm] [DirectX] Add support to lower LLVM intrinsics ceil, cos, fabs, floor and smax to DXIL Ops. (PR #78767)

[S. Bharadwaj Yadavalli via llvm-commits]

bharadwajy wrote:

I think this PR needs some refinements. Marking it as draft to get feedback, if possible.

https://github.com/llvm/llvm-project/pull/78767