[clang] [llvm] [mlir] IR: Promote "denormal-fp-math" to a first class attribute (PR #174293)

[Nikita Popov via cfe-commits]

nikic wrote:

> That would be a bit irregular, because the next entry isn't part of the same list. preserve-sign, preserve-sign, float aren't the same kind. It's two pairs, one with a name prefix. If there were some other separator character for the pair elements?

This is true, but I think the meaning is still pretty obvious and we have precedent for this in `captures()`. I guess you could use `;` if you really wanted to distinguish them.

> Strictly speaking, no. But it's also unpleasant to duplicate hundreds of test functions that only differ by an attribute

Okay, fine to keep it then.

https://github.com/llvm/llvm-project/pull/174293