Graham Hunter via llvm-dev
2019-Mar-15 10:18 UTC
[llvm-dev] Scalable Vector Types in IR - Next Steps?
Hi David,> We tried two round tables at the Nov. LLVMDev and no serious objections > were raised, but we knew we didn't have all the right people there. I > am somewhat skeptical another roundtable without commitment to attend > from all able parties ahead of time will accomplish much.Agreed, but I'll try scheduling one anyway.> Speaking for myself (and not Cray), it is frustrating to have had a > bunch of discussion on the mailing list and in reviews where concerns > were raised and to see a lot of radio silence to responses to those > concerns, only to see a message about a potential change in direction > driven by off-list discussions where concerns and responses to concerns > are unknown and therefore not addressable.I didn't want private meetings either, but repeatedly requesting public feedback for the RFC or patches hadn't provided reasoning behind any concerns that people had. The agreement reached at the meeting was for the objectors to post their reasons for objecting and counter-proposal in public so discussion could take place, and Arm would investigate the details of the counter-proposal. Unfortunately, that post never happened, so I found myself a bit stuck and had to post it for them -- not a situation I wanted. I have always wanted the discussion to take place in public.> I completely understand that ARM needs to make progress and I very much > want to see that progress. I just don't want to see a Plan B leading to > a situation where VLA support doesn't ever make it into LLVM. It is > somewhat embarrassing that gcc already has a release with VLA support > for SVE and LLVM is stuck in the starting blocks.Agreed. -Graham
Finkel, Hal J. via llvm-dev
2019-Mar-15 15:30 UTC
[llvm-dev] Scalable Vector Types in IR - Next Steps?
On 3/15/19 5:18 AM, Graham Hunter via llvm-dev wrote:> Hi David, > >> We tried two round tables at the Nov. LLVMDev and no serious objections >> were raised, but we knew we didn't have all the right people there. I >> am somewhat skeptical another roundtable without commitment to attend >> from all able parties ahead of time will accomplish much. > Agreed, but I'll try scheduling one anyway. > >> Speaking for myself (and not Cray), it is frustrating to have had a >> bunch of discussion on the mailing list and in reviews where concerns >> were raised and to see a lot of radio silence to responses to those >> concerns, only to see a message about a potential change in direction >> driven by off-list discussions where concerns and responses to concerns >> are unknown and therefore not addressable. > I didn't want private meetings either, but repeatedly requesting public > feedback for the RFC or patches hadn't provided reasoning behind any > concerns that people had. > > The agreement reached at the meeting was for the objectors to post their > reasons for objecting and counter-proposal in public so discussion could > take place, and Arm would investigate the details of the counter-proposal.I've talked with a number of people about this as well, and I think that I understand the objections. I'm happy that ARM followed through with the alternate set of patches. Regardless, however, unless those who had wished to object still wish to object, and then actually do so, we now clearly have a good collection of contributors actively desiring to do code review, and we should move forward (i.e., start committing patches once they're judged ready). -Hal> > Unfortunately, that post never happened, so I found myself a bit stuck and > had to post it for them -- not a situation I wanted. > > I have always wanted the discussion to take place in public. > >> I completely understand that ARM needs to make progress and I very much >> want to see that progress. I just don't want to see a Plan B leading to >> a situation where VLA support doesn't ever make it into LLVM. It is >> somewhat embarrassing that gcc already has a release with VLA support >> for SVE and LLVM is stuck in the starting blocks. > Agreed. > > -Graham > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev-- Hal Finkel Lead, Compiler Technology and Programming Languages Leadership Computing Facility Argonne National Laboratory
Renato Golin via llvm-dev
2019-Mar-15 15:38 UTC
[llvm-dev] Scalable Vector Types in IR - Next Steps?
On Fri, 15 Mar 2019 at 15:30, Finkel, Hal J. via llvm-dev <llvm-dev at lists.llvm.org> wrote:> I've talked with a number of people about this as well, and I think that > I understand the objections. I'm happy that ARM followed through with > the alternate set of patches. Regardless, however, unless those who had > wished to object still wish to object, and then actually do so, we now > clearly have a good collection of contributors actively desiring to do > code review, and we should move forward (i.e., start committing patches > once they're judged ready).Let's start by closing the three flying revisions, so that people that weren't involved in the discussion don't waste time looking at them. Graham, can you also add a comment to reflect the change in implementation while closing? Second, it would be very good if someone, anyone, would write an RFC on the new proposal. Graham started it on this thread and on the two reviews, but this thread is now dead. We should have a new one, with subject "RFC etc" and the contents of the current understanding, so that it can serve as context for the two reviews. Thanks! --renato
David Greene via llvm-dev
2019-Mar-15 15:54 UTC
[llvm-dev] Scalable Vector Types in IR - Next Steps?
Graham Hunter <Graham.Hunter at arm.com> writes:> I have always wanted the discussion to take place in public.I just want to make sure you know that we all know that. I was not in any way disparaging the work you and ARM have done on this! -David
David Greene via llvm-dev
2019-Mar-15 15:57 UTC
[llvm-dev] Scalable Vector Types in IR - Next Steps?
"Finkel, Hal J." <hfinkel at anl.gov> writes:>> The agreement reached at the meeting was for the objectors to post their >> reasons for objecting and counter-proposal in public so discussion could >> take place, and Arm would investigate the details of the counter-proposal. > > > I've talked with a number of people about this as well, and I think that > I understand the objections. I'm happy that ARM followed through with > the alternate set of patches. Regardless, however, unless those who had > wished to object still wish to object, and then actually do so, we now > clearly have a good collection of contributors actively desiring to do > code review, and we should move forward (i.e., start committing patches > once they're judged ready).I am not sure this is your intended meaning, but if those objecting don't come forward, I would like to see Graham's current patches supporting scalable types go in. A number of people have now stated that they are desirable, people have reviewed them, Graham has made changes and we're ready to review them some more and iterate on them. It would set a bad precedent to block patches based on some vague objections that aren't being discussed publicly. We can debate the actual patches, that of course needs to happen. But the RFC looks reasonable to me and apparently others. Let's start moving forward. -David