[llvm-branch-commits] [llvm] [AArch64] SLP can vectorize frem (PR #82488)

[Alexey Bataev via llvm-branch-commits]

alexey-bataev wrote:

> Personally I'm happy with keeping this nuance outside of TTI but if we really want this captured within TTI then I think it's time to break FREM into its own cost function (i.e. implement getFRemInstrCost. That way getArithmeticInstrCost can work as it does today and the new function can be documented to highlight it's assumption that if a TLI is passed in and a vector mapping is present then the return value is only valid based on it's assumption that vector FREM instructions will be transformed by a following transformation pass. I prefer this to say, adding TLI to getArithmeticInstrCost, because I'd rather users of getFRemInstrCost to explicitly enter into this contract.

Hm, not sure adding getFRemInstrCost is the best solution here. I would more support adding TLI to getArithmeticInstrCost instead. Some other users may benefit from this too. Though getFRemInstrCost is still better than the current solution

https://github.com/llvm/llvm-project/pull/82488