[llvm] Attributor: Add denormal-fp-math to attributor-light (PR #79576)

[Johannes Doerfert via llvm-commits]

jdoerfert wrote:

> I think it's quite unlikely that AttributorLight will become part of the default pipeline anytime soon, especially if more attributes get added to it. So if you need this, you do need to implement it in the production FunctionAttrs pass. Unless this is a for a custom, non-upstream pipeline?

Could you elaborate why that is? 

https://github.com/llvm/llvm-project/pull/79576