[llvm] [AArch64] Add bitcasts for lowering saturating add/sub and shift intrinsics. (PR #161840)

[via llvm-commits]

Lukacma wrote:

Thanks David for taking time to look at this. I am a bit confused by your comment though. Are you fine with generalizing the intrinsics to allow for floating point types or are you fine with having duplicate patterns, one for GlobalIsel second for SelectionDAG ?

As for your question, yes this should be all intrinsics. I think there are no i8/i16 specific ones as these types behave the same as i32/i64 so they don't need their own special intrinsics.  

https://github.com/llvm/llvm-project/pull/161840