[llvm] [NVPTX] Implement isTruncateFree and isZExtFree for i32/i64 Optimizations (PR #114601)

[Alex MacLean via llvm-commits]

AlexMaclean wrote:

Could you please add some lit tests to this PR to demonstrate what the intended impact of this change is?

https://github.com/llvm/llvm-project/pull/114601