[llvm] [NVPTX] Constant-folding for f2i, d2ui, f2ll etc. (PR #118965)

[Alex MacLean via llvm-commits]

https://github.com/AlexMaclean commented:

Overall seems reasonable to me, I agree it seems good to constant fold these intrinsics. I'm not too familiar with ConstantFolding though so I can't say if it's okay to add so much target-specific code here. 

https://github.com/llvm/llvm-project/pull/118965