[Bug rtl-optimization/101523] Huge number of combine attempts

["segher at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101523

--- Comment #63 from Segher Boessenkool <segher at gcc dot gnu.org> ---
(In reply to Sarah Julia Kriesch from comment #62)
> (In reply to Segher Boessenkool from comment #61)
> > (In reply to Sarah Julia Kriesch from comment #60)
> > > I have to agree with Richard. This problem has been serious for a long time
> > > but has been ignored by IBM based on distribution choices.
> > 
> > What?  What does IBM have to do with this?  Yes, they are my employer, but
> > what I decide is best for combine to do is not influenced by them *at all*
> > (except some times they want me to spend time doing paid work, distracting
> > me from things that really matter, like combine!)
> > 
> Then, tell other reasons why my requests in the openSUSE bug report have
> been rejected in the past, and this bug report has been open for 3 years.
> Perhaps it is helpful to know that IBM has fixed memory issues in PostgreSQL
> (for openSUSE/upstream) with higher quality via my request with the support
> for Red Hat (and faster).

Once again, I have no idea what you are talking about.  It sounds like some
complot theory?  Exciting!

I really have no idea what you are talking about.  I recognise some of the
words, but not enough to give me a handle on what you are on about.

> > > Anyway, we want to live within the open source community without any Linux
> > > distribution priorities (especially in upstream projects like here).
> > 
> > No idea what that means either.
> > 
> There is a reason for founding the Linux Distributions Working Group at the
> Open Mainframe Project (equality for all Linux Distributions on s390x).
> SUSE, Red Hat and Canonical have been supporting this idea also (especially
> based on my own work experience at IBM and the priorities inside).

And here I don't have any context either.

> > > Segher, can you specify the failed test cases? Then, it should be possible
> > > to reproduce and improve that all. In such a collaborative way, we can also
> > > achieve a solution.
> > 
> > What failed test cases?  You completely lost me.
> > 
> This one:
> (In reply to Segher Boessenkool from comment #57)
> > (In reply to Richard Biener from comment #56)
> > PR101523 is a very serious problem, way way way more "P1" than any of the
> > "my target was inconvenienced by some bad testcases failing now" "P1"s there
> > are now.  Please undo this!

They are in this PR.  "See Also", top right corner in the headings.

> (In reply to Segher Boessenkool from comment #61)
> > We used to do the wrong thing in combine.  Now that my fix was reverted, we
> > still do.  This should be undone soonish, so that I can commit an actual
> > UNCSE
> > implementation, which fixes all "regressions" (quotes, because they are not!)
> > caused by my previous patch, and does a lot more too.  It also will allow us
> > to remove a bunch of other code from combine, speeding up things a lot more
> > (things that keep a copy of a set if the dest is used more than once).  There
> > has been talk of doing an UNCSE for over twenty years now, so annoying me
> > enough to get this done is a good result of this whole thing :-)
> Your fixes should also work with upstream code and the used gcc versions in
> our/all Linux distributions. I recommend applying tests and merging your
> fixes to at least one gcc version.

Lol.  No.  Distributions have to sort out their own problems.  I don't have
a copy of an old version of most distros even; I haven't *heard* about the
*existence* of most distros!

I don't use a Linux distro on any of my own machines.  And I care about some
other OSes at least as much, btw.  And not just because my employer cares about
some of those.

> If you want to watch something about our reasons for creating a
> collaboration between Linux distributions (and upstream projects), you
> should watch my first presentation "Collaboration instead of Competition":
> https://av.tib.eu/media/57010
> 
> Hint: The IBM statement came from my former IBM Manager (now your CPO).

CPO?  What is a CPO?  I don't think I have any?  I do have an R2 somewhere,
does that help?