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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/59967] [11/12/13/14 Regression] Performance regression from 4.7.x to 4.8.x (loop not unrolled)
Date: Mon, 11 Mar 2024 06:18:07 +0000	[thread overview]
Message-ID: <bug-59967-4-7aZoRniKxd@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-59967-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59967

--- Comment #23 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
One thing unrelated to the unrolling I Noticed is:
```
  if (_221 != 0)
    goto <bb 50>; [50.00%]
  else
    goto <bb 49>; [50.00%]

  <bb 49> [local count: 163152564]:
  _212 = _218 - s_202;
  goto <bb 51>; [100.00%]

  <bb 50> [local count: 163152564]:
  _222 = s_202 + _218;

  <bb 51> [local count: 326305128]:
  # ck0$0_144 = PHI <_218(49), _222(50)>
  # prephitmp_211 = PHI <_212(49), _218(50)>
```

Does not use conditional moves on aarch64 (or x86_64) even though it
could/should.
That pattern shows up 3 times due to the unrolling of the inner loop there.
```
   ck0[j] = c0[j];
   if (1<<j & i)
    ck0[j] += s;
   if (r->rop[j] < ck0[j] - 1.0*s)
```

      parent reply	other threads:[~2024-03-11  6:18 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-28 13:12 [Bug c/59967] New: " chbreitkopf at gmail dot com
2014-01-29 13:49 ` [Bug tree-optimization/59967] [4.8/4.9 Regression] " rguenth at gcc dot gnu.org
2014-04-02 23:17 ` hubicka at ucw dot cz
2014-04-03  6:18 ` chbreitkopf at gmail dot com
2014-05-22  9:01 ` [Bug tree-optimization/59967] [4.8/4.9/4.10 " rguenth at gcc dot gnu.org
2014-12-19 13:40 ` [Bug tree-optimization/59967] [4.8/4.9/5 " jakub at gcc dot gnu.org
2015-01-15 14:44 ` rguenth at gcc dot gnu.org
2015-01-15 14:44 ` rguenth at gcc dot gnu.org
2015-03-18 13:17 ` rguenth at gcc dot gnu.org
2015-06-23  8:23 ` [Bug tree-optimization/59967] [4.8/4.9/5/6 " rguenth at gcc dot gnu.org
2015-06-26 20:13 ` [Bug tree-optimization/59967] [4.9/5/6 " jakub at gcc dot gnu.org
2015-06-26 20:36 ` jakub at gcc dot gnu.org
2015-06-30 11:02 ` rguenth at gcc dot gnu.org
2021-05-14  9:47 ` [Bug tree-optimization/59967] [9/10/11/12 " jakub at gcc dot gnu.org
2021-06-01  8:06 ` rguenth at gcc dot gnu.org
2022-05-27  9:35 ` [Bug tree-optimization/59967] [10/11/12/13 " rguenth at gcc dot gnu.org
2022-06-28 10:30 ` jakub at gcc dot gnu.org
2023-07-07 10:30 ` [Bug tree-optimization/59967] [11/12/13/14 " rguenth at gcc dot gnu.org
2024-03-11  6:18 ` pinskia at gcc dot gnu.org [this message]

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