[Bug middle-end/110757] [14 Regression] 7% parest regression on zen3 -Ofast -march=native -flto between g:4dbb3af1efe55174 (2023-07-14 00:54) and g:a5088dc3f5ef73c8 (2023-07-17 03:24)

2024-03-07 Thread law at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110757

Jeffrey A. Law  changed:

   What|Removed |Added

   Priority|P3  |P2
 CC||law at gcc dot gnu.org

[Bug middle-end/110757] [14 Regression] 7% parest regression on zen3 -Ofast -march=native -flto between g:4dbb3af1efe55174 (2023-07-14 00:54) and g:a5088dc3f5ef73c8 (2023-07-17 03:24)

2023-07-26 Thread hubicka at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110757

--- Comment #4 from Jan Hubicka  ---
Most of the profile based regression is gone between
g:1c6231c05bdccab3 (2023-07-21 03:06)
and 
g:f33fdf9e7c038639 (2023-07-23 00:17)

This should be:
commit a31ef26b056d0c4f0a9f08b6eb81456ea257298e
Author: Jan Hubicka 
Date:   Fri Jul 21 19:38:26 2023 +0200

Avoid scaling flat loop profiles of vectorized loops

Which "fixes" the overactive scaling of scale_profile_for_vect_loop
for static profiles.
Still not sure why propagating profile later causes regression - will take a
look.

[Bug middle-end/110757] [14 Regression] 7% parest regression on zen3 -Ofast -march=native -flto between g:4dbb3af1efe55174 (2023-07-14 00:54) and g:a5088dc3f5ef73c8 (2023-07-17 03:24)

2023-07-22 Thread jamborm at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110757

Martin Jambor  changed:

   What|Removed |Added

 CC||lili.cui at intel dot com,
   ||rguenth at gcc dot gnu.org
   Last reconfirmed||2023-07-22
 Status|UNCONFIRMED |NEW
 Ever confirmed|0   |1

--- Comment #3 from Martin Jambor  ---
And while I am at it, the 2.5% slowdown in April was caused by Richi's
r14-332-g24905a4bd1375c (Adjust costing of emulated vectorized
gather/scatter) and the 2.8% regression in May by 2.8% is caused by
r14-1371-ge5405f065bace0 (Handle FMA friendly in reassoc pass).

Both are small and so may not warrant their own bug-report but together
they make up almost 6% and we are now 13% slower than GCC 13 on zen 3
and 2 (on the Intel machine in LNT it is just 2.7% and I see no
regression on the Aarch64 one).

[Bug middle-end/110757] [14 Regression] 7% parest regression on zen3 -Ofast -march=native -flto between g:4dbb3af1efe55174 (2023-07-14 00:54) and g:a5088dc3f5ef73c8 (2023-07-17 03:24)

2023-07-21 Thread jamborm at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110757

--- Comment #2 from Martin Jambor  ---
The second slow-down of 4.5% was caused by r14-2546-g061f74c06735e1:

061f74c06735e1fa35b910ae0bcf01b61a74ec23 is the first bad commit
commit 061f74c06735e1fa35b910ae0bcf01b61a74ec23
Author: Jan Hubicka 
Date:   Sun Jul 16 23:56:59 2023 +0200

Fix profile update in scale_profile_for_vect_loop

When vectorizing 4 times, we sometimes do
  for
<4x vectorized body>
  for
<2x vectorized body>
  for
<1x vectorized body>

Here the second two fors handling epilogue never iterates.
Currently vecotrizer thinks that the middle for itrates twice.
This turns out to be scale_profile_for_vect_loop that uses
niter_for_unrolled_loop.

[Bug middle-end/110757] [14 Regression] 7% parest regression on zen3 -Ofast -march=native -flto between g:4dbb3af1efe55174 (2023-07-14 00:54) and g:a5088dc3f5ef73c8 (2023-07-17 03:24)

2023-07-21 Thread jamborm at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110757

Martin Jambor  changed:

   What|Removed |Added

 CC||jamborm at gcc dot gnu.org

--- Comment #1 from Martin Jambor  ---
The first (2%) slowdown seems to be due to r14-2524-gaa6741ef2e0c31
(Turn TODO_rebuild_frequencies to a pass), I'm now bisecting the
bigger one.

[Bug middle-end/110757] [14 Regression] 7% parest regression on zen3 -Ofast -march=native -flto between g:4dbb3af1efe55174 (2023-07-14 00:54) and g:a5088dc3f5ef73c8 (2023-07-17 03:24)

2023-07-20 Thread pinskia at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110757

Andrew Pinski  changed:

   What|Removed |Added

   Keywords||missed-optimization
Summary|7% parest regression on |[14 Regression] 7% parest
   |zen3 -Ofast -march=native   |regression on zen3 -Ofast
   |-flto between   |-march=native -flto between
   |g:4dbb3af1efe55174  |g:4dbb3af1efe55174
   |(2023-07-14 00:54) and  |(2023-07-14 00:54) and
   |g:a5088dc3f5ef73c8  |g:a5088dc3f5ef73c8
   |(2023-07-17 03:24)  |(2023-07-17 03:24)
   Target Milestone|--- |14.0
 CC||pinskia at gcc dot gnu.org
Version|13.1.0  |14.0