Drop this patch since
https://gcc.gnu.org/pipermail/gcc-patches/2025-June/686830.html could
be a better alternative.
On Tue, Jun 10, 2025 at 9:50 AM Hongtao Liu <crazy...@gmail.com> wrote:
>
> Ping
>
> On Mon, May 19, 2025 at 10:06 AM liuhongt <hongtao....@intel.com> wrote:
> >
> > From: "hongtao.liu" <hongtao....@intel.com>
> >
> > AutoFDO profile is a scaled profile, as a result, 0 sample does not
> > mean never executed. especially there's profile from function
> > body. Prevent combine_with_ipa_count·(ipa_count) from zeroing all
> > bb->count.
> >
> > Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}
> > OK for trunk?
> >
> > gcc/ChangeLog:
> >
> > PR gcov-profile/118551
> > * predict.cc (estimate_bb_frequencies): Prevent
> > combine_with_ipa_count·(ipa_count) from zeroing all bb->count
> > when function body is known to be hot.
> > ---
> > gcc/predict.cc | 73 +++++++++++++++++++++++++++++---------------------
> > 1 file changed, 42 insertions(+), 31 deletions(-)
> >
> > diff --git a/gcc/predict.cc b/gcc/predict.cc
> > index ef31c48bfe2..7d4bf5261ad 100644
> > --- a/gcc/predict.cc
> > +++ b/gcc/predict.cc
> > @@ -4105,40 +4105,51 @@ estimate_bb_frequencies ()
> > if (freq_max < 16)
> > freq_max = 16;
> > profile_count ipa_count = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.ipa ();
> > - cfun->cfg->count_max = profile_count::uninitialized ();
> > - FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), NULL, next_bb)
> > +
> > + /* AutoFDO profile is a scaled profile, as a result, 0 sample does not
> > + mean never executed. especially there's profile from function
> > + body. Prevent combine_with_ipa_count·(ipa_count) from zeroing all
> > + bb->count. */
> > + if (!(ipa_count.quality () == AFDO
> > + && cfun->cfg->count_max.quality () == AFDO
> > + && !ipa_count.nonzero_p ()
> > + && cfun->cfg->count_max.nonzero_p ()))
> > {
> > - sreal tmp = BLOCK_INFO (bb)->frequency;
> > - if (tmp >= 1)
> > + cfun->cfg->count_max = profile_count::uninitialized ();
> > + FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), NULL, next_bb)
> > {
> > - gimple_stmt_iterator gsi;
> > - tree decl;
> > -
> > - /* Self recursive calls can not have frequency greater than 1
> > - or program will never terminate. This will result in an
> > - inconsistent bb profile but it is better than greatly confusing
> > - IPA cost metrics. */
> > - for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
> > - if (is_gimple_call (gsi_stmt (gsi))
> > - && (decl = gimple_call_fndecl (gsi_stmt (gsi))) != NULL
> > - && recursive_call_p (current_function_decl, decl))
> > - {
> > - if (dump_file)
> > - fprintf (dump_file, "Dropping frequency of recursive call"
> > - " in bb %i from %f\n", bb->index,
> > - tmp.to_double ());
> > - tmp = (sreal)9 / (sreal)10;
> > - break;
> > - }
> > + sreal tmp = BLOCK_INFO (bb)->frequency;
> > + if (tmp >= 1)
> > + {
> > + gimple_stmt_iterator gsi;
> > + tree decl;
> > +
> > + /* Self recursive calls can not have frequency greater than 1
> > + or program will never terminate. This will result in an
> > + inconsistent bb profile but it is better than greatly
> > confusing
> > + IPA cost metrics. */
> > + for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next
> > (&gsi))
> > + if (is_gimple_call (gsi_stmt (gsi))
> > + && (decl = gimple_call_fndecl (gsi_stmt (gsi))) != NULL
> > + && recursive_call_p (current_function_decl, decl))
> > + {
> > + if (dump_file)
> > + fprintf (dump_file, "Dropping frequency of recursive
> > call"
> > + " in bb %i from %f\n", bb->index,
> > + tmp.to_double ());
> > + tmp = (sreal)9 / (sreal)10;
> > + break;
> > + }
> > + }
> > + tmp = tmp * freq_max;
> > + profile_count count = profile_count::from_gcov_type
> > (tmp.to_nearest_int ());
> > +
> > + /* If we have profile feedback in which this function was never
> > + executed, then preserve this info. */
> > + if (!(bb->count == profile_count::zero ()))
> > + bb->count = count.guessed_local ().combine_with_ipa_count
> > (ipa_count);
> > + cfun->cfg->count_max = cfun->cfg->count_max.max (bb->count);
> > }
> > - tmp = tmp * freq_max;
> > - profile_count count = profile_count::from_gcov_type
> > (tmp.to_nearest_int ());
> > -
> > - /* If we have profile feedback in which this function was never
> > - executed, then preserve this info. */
> > - if (!(bb->count == profile_count::zero ()))
> > - bb->count = count.guessed_local ().combine_with_ipa_count
> > (ipa_count);
> > - cfun->cfg->count_max = cfun->cfg->count_max.max (bb->count);
> > }
> >
> > free_aux_for_blocks ();
> > --
> > 2.34.1
> >
>
>
> --
> BR,
> Hongtao
--
BR,
Hongtao
