2016-12-23 17:22 GMT+01:00 Davide Italiano <davide at freebsd.org>:> On Fri, Dec 23, 2016 at 8:12 AM, Piotr Padlewski via llvm-dev > <llvm-dev at lists.llvm.org> wrote: > > Hi everyone, > > > > I started digging into MemDep to enhance devirtualization and I found out > > that it doesn't handle invariant.group if it will find GEP 0, 0. > > If I understand it correctly getelementptr with zeros is just bitcast. Is > > there any good reason why it is not canonicalized into bitcast? > > > > Hi, > is there any particular reason why you're trying to fix this in MemDep > (and not in MemSSA?) > > GVN uses MemDep and MemSSA doesn't handle invariant.group. I was toldthat MemDep won't go out soon and it is easier for me right now to fix my stuff there than in MemSSA. I have plans to write support for MemSSA, but probably not in near future.> -- > Davide > > "There are no solved problems; there are only problems that are more > or less solved" -- Henri Poincare >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161223/23f54487/attachment.html>
Define soon? My guess is 1 year or less. (I've already seen patches to start converting most remaining memdep uses, like memcpy opt, licm, etc) On Fri, Dec 23, 2016 at 8:27 AM, Piotr Padlewski via llvm-dev < llvm-dev at lists.llvm.org> wrote:> > > 2016-12-23 17:22 GMT+01:00 Davide Italiano <davide at freebsd.org>: > >> On Fri, Dec 23, 2016 at 8:12 AM, Piotr Padlewski via llvm-dev >> <llvm-dev at lists.llvm.org> wrote: >> > Hi everyone, >> > >> > I started digging into MemDep to enhance devirtualization and I found >> out >> > that it doesn't handle invariant.group if it will find GEP 0, 0. >> > If I understand it correctly getelementptr with zeros is just bitcast. >> Is >> > there any good reason why it is not canonicalized into bitcast? >> > >> >> Hi, >> is there any particular reason why you're trying to fix this in MemDep >> (and not in MemSSA?) >> >> GVN uses MemDep and MemSSA doesn't handle invariant.group. I was told > that MemDep won't go out soon and it is easier for me right now to fix my > stuff there than in MemSSA. I have plans to write support for MemSSA, but > probably not in near future. > > >> -- >> Davide >> >> "There are no solved problems; there are only problems that are more >> or less solved" -- Henri Poincare >> > > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161223/c01097b6/attachment.html>
On Dec 23, 2016 19:47, "Daniel Berlin" <dberlin at dberlin.org> wrote: Define soon? My guess is 1 year or less. (I've already seen patches to start converting most remaining memdep uses, like memcpy opt, licm, etc) That's good. Anyway I already have a patch that is doing invariant group dependence across BBs, so I guess it make sense to push it upstream to push the bar higher. But I think we are getting a little bit of topic - should gep 0 be canonicalized to bitcast? Piotr On Fri, Dec 23, 2016 at 8:27 AM, Piotr Padlewski via llvm-dev < llvm-dev at lists.llvm.org> wrote:> > > 2016-12-23 17:22 GMT+01:00 Davide Italiano <davide at freebsd.org>: > >> On Fri, Dec 23, 2016 at 8:12 AM, Piotr Padlewski via llvm-dev >> <llvm-dev at lists.llvm.org> wrote: >> > Hi everyone, >> > >> > I started digging into MemDep to enhance devirtualization and I found >> out >> > that it doesn't handle invariant.group if it will find GEP 0, 0. >> > If I understand it correctly getelementptr with zeros is just bitcast. >> Is >> > there any good reason why it is not canonicalized into bitcast? >> > >> >> Hi, >> is there any particular reason why you're trying to fix this in MemDep >> (and not in MemSSA?) >> >> GVN uses MemDep and MemSSA doesn't handle invariant.group. I was told > that MemDep won't go out soon and it is easier for me right now to fix my > stuff there than in MemSSA. I have plans to write support for MemSSA, but > probably not in near future. > > >> -- >> Davide >> >> "There are no solved problems; there are only problems that are more >> or less solved" -- Henri Poincare >> > > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161223/4bbc0c97/attachment.html>