Re: [PATCH] sched-rgn: run add_branch_dependencies for sel-sched (PR 84301)

[Vladimir Makarov <vmakarov at redhat dot com>]

On 04/11/2018 06:15 AM, Andrey Belevantsev wrote:
> On 10.04.2018 14:09, Alexander Monakov wrote:
> > Hi,
> >
> > The add_branch_dependencies function is fairly unusual in that it creates
> > dependence edges "out of thin air" for all sorts of instructions preceding
> > BB end. I think that is really unfortunate (explicit barriers in RTL would
> > be more natural), but I've already complained about that in the PR.
> >
> > The bug/regression is that this function was not run for sel-sched, but the
> > testcase uncovers that moving a USE away from the return insn can break
> > assumptions in mode-switching code.
> >
> > Solve this by running the first part of add_branch_dependencies where it
> > sets CANT_MOVE flags on immovable non-branch insns.
> >
> > Bootstrapped/regtested on x86_64 with sel-sched active. OK to apply?
> Looks fine to me but I cannot approve -- maybe Vladimir can take a look?
The patch is ok for me.  Thanks for working on the PR.