[llvm-dev] How to get information about data dependencies?

David Greene via llvm-dev
Tue, 07 Jul 2020 21:15:29 -0000

Stefanos Baziotis via llvm-dev <llvm-dev at lists.llvm.org> writes:

> In any case, I would strongly prefer that we don't follow the LAA
> path, since I don't think it has potential anyway. I think that we
> should try to find a way to extend it that is also based on strong
> theoretical foundation and maintains the high quality of code.

Just to be clear, you don't think it has potential because it's been
disgned into an inner-loop corner and would take extensive rewriting to
handle OLV?

> Tell me what you think and I'm looking forward to more people jumping
in.

If my supposition above is correct, it certainly seems like extending DA
is the way to go but I'd like to hear from the current vectorizer
maintainers because I don't have enough knowledge to make an informed
judgment.

There's the VPlan infrastructure which I have not heard much about for
several months.  What is going on with that?  Yes, that's a vector
codegen issue but it may be useful to have a more complete picture of
how all this works or will work.

                   -David