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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/104582] [11/12 Regression] Unoptimal code for __negdi2 (and others) from libgcc2 due to unwanted vectorization
Date: Thu, 17 Feb 2022 16:35:57 +0000	[thread overview]
Message-ID: <bug-104582-4-HHf7N9yBDS@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-104582-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104582

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
What slp does is just
-  w.s.low = _1;
-  w.s.high = _5;
+  _14 = {_1, _5};
+  MEM[(union  *)&w] = _14;
I must say I don't really see that as a beneficial optimization, construction
of a vector from scalars just to store it in memory doesn't look ever like a
win.

  parent reply	other threads:[~2022-02-17 16:35 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-02-17 12:30 [Bug target/104582] New: Unoptimal code for __negdi2 (and others) from libgcc2 ubizjak at gmail dot com
2022-02-17 12:35 ` [Bug tree-optimization/104582] " ubizjak at gmail dot com
2022-02-17 12:45 ` ubizjak at gmail dot com
2022-02-17 15:28 ` [Bug tree-optimization/104582] [11/12 Regression] Unoptimal code for __negdi2 (and others) from libgcc2 due to unwanted vectorization jakub at gcc dot gnu.org
2022-02-17 16:35 ` jakub at gcc dot gnu.org [this message]
2022-02-17 16:40 ` jakub at gcc dot gnu.org
2022-02-18  0:43 ` pinskia at gcc dot gnu.org
2022-02-18  7:26 ` rguenth at gcc dot gnu.org
2022-02-18  8:37 ` jakub at gcc dot gnu.org
2022-02-18  8:48 ` rguenth at gcc dot gnu.org
2022-02-18  8:53 ` rguenth at gcc dot gnu.org
2022-02-18  9:02 ` jakub at gcc dot gnu.org
2022-02-18  9:28 ` rguenther at suse dot de
2022-02-18 10:19 ` rguenth at gcc dot gnu.org
2022-02-18 10:22 ` rguenth at gcc dot gnu.org
2022-02-18 10:50 ` rguenth at gcc dot gnu.org
2022-02-18 11:31 ` rguenth at gcc dot gnu.org
2022-02-18 13:37 ` rguenth at gcc dot gnu.org
2022-02-18 13:45 ` rguenth at gcc dot gnu.org
2022-02-18 21:16 ` pinskia at gcc dot gnu.org
2022-02-22  7:58 ` cvs-commit at gcc dot gnu.org
2022-02-22  7:59 ` cvs-commit at gcc dot gnu.org
2022-02-22  7:59 ` cvs-commit at gcc dot gnu.org
2022-02-22  7:59 ` [Bug tree-optimization/104582] [11 " rguenth at gcc dot gnu.org
2022-04-07  8:15 ` rguenth at gcc dot gnu.org
2022-04-21  7:51 ` rguenth at gcc dot gnu.org
2023-05-29 10:06 ` jakub at gcc dot gnu.org

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