On Sat, Sep 6, 2008 at 11:24 AM, Luis Machado <[EMAIL PROTECTED]> wrote: > > On Sat, 2008-09-06 at 07:49 -0700, H.J. Lu wrote: >> On Sat, Sep 6, 2008 at 7:05 AM, Luis Machado <[EMAIL PROTECTED]> wrote: >> > >> > On Fri, 2008-09-05 at 10:34 -0700, H.J. Lu wrote: >> >> On Fri, Sep 5, 2008 at 10:24 AM, Vladimir Makarov <[EMAIL PROTECTED]> >> >> wrote: >> >> > >> >> > H.J. Lu keeps ira-branch merge more fresh than trunk. But the lag is >> >> > only >> >> >> >> I won't apply any non-IRA related patches to ira-merge branch so >> >> that you can get a fair comparison for IRA without regressions >> >> introduced by other changes. >> >> >> >> > 1-3 days usually because gcc community and RA reviewers are very >> >> > responsive. >> >> > So I don't see a big difference in using ira-merge and trunk. I'd only >> >> > recommend to apply patch >> >> > >> >> > http://gcc.gnu.org/ml/gcc-patches/2008-09/msg00427.html >> >> > >> >> > first because it is critical for performance but I don't know when it >> >> > will >> >> > be approved. >> >> > >> >> >> >> I checked this patch into ira-merge branch. >> > >> > I've verifired applu and facerec against the ira-merge branch. The >> > numbers are just as bad as trunk. So, apparently, the last patch didn't >> > improve performance on those benchmarks. >> > >> > Any other ideas you'd like me to try on IRA? >> > >> > >> >> Can you verify if your problem is related to >> >> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28690 > > Even with data that shows us that the degradation occured between > revisions 139589 and 139590 (139589 showing good numbers and 139590 > showing bad numbers), would it still make sense to consider ticket 28690 > as the possible reason for this degradation? > >
My understanding is PowerPC is quite sensitive to choice of register as shown in PR 28690. IRA merge may make fixes for PR 28690 ineffective. There are a few small testcases in PR 28690. You can check if those problems in PR 28690 come back due to IRA merge. Also, IRA disables regmove: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37364 I don't know its impact on PowerPC. Can you try --- ./regmove.c.regmove 2008-09-06 10:09:43.000000000 -0700 +++ ./regmove.c 2008-09-06 11:34:24.000000000 -0700 @@ -1117,8 +1117,7 @@ regmove_optimize (rtx f, int nregs) for (pass = 0; pass <= 2; pass++) { - /* We need fewer optimizations for IRA. */ - if ((! flag_regmove || flag_ira) && pass >= flag_expensive_optimizations) + if ((! flag_regmove) && pass >= flag_expensive_optimizations) goto done; if (dump_file) @@ -1167,8 +1166,7 @@ regmove_optimize (rtx f, int nregs) } } - /* All optimizations important for IRA have been done. */ - if (! flag_regmove || flag_ira) + if (! flag_regmove) continue; if (! find_matches (insn, &match)) on the current ira-merge branch. -- H.J.
