[llvm-dev] Selection DAG chain question

[Tim Northover via llvm-dev]

On Thu, 16 Jul 2020 at 16:44, Hendrik Greving via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
> But then the new nodes are not chained with respect to other nodes, or not chained with respect to each other, in case there are several UDIVREM.

Do they really need to be chained with each other or anything else?
The case I know of is when they get lowered to a libcall. That libcall
has effects that mean it needs a chain of some kind, but it doesn't
really matter in any other way where in the basic block it happens.

As long as it's after its inputs have been created and before its
outputs are consumed, everything is fine. And that's handled by the
normal value operands.

Cheers.

Tim.