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From: "krebbel at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/101523] Huge number of combine attempts
Date: Thu, 07 Mar 2024 09:34:00 +0000	[thread overview]
Message-ID: <bug-101523-4-KWFurWwl96@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-101523-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101523

--- Comment #21 from Andreas Krebbel <krebbel at gcc dot gnu.org> ---
(In reply to Segher Boessenkool from comment #16)
...
> When some insns have changed (or might have changed, combine does not always
> know
> the details), combinations of the insn with later insns are tried again. 
> Sometimes
> this finds new combination opportunities.
> 
> Not retrying combinations after one of the insns has changed would be a
> regression.

Wouldn't it in this particular case be possible to recognize already in
try_combine that separating the move out of the parallel cannot lead to
additional optimization opportunities? To me it looks like we are just
recreating the situation we had before merging the INSNs into a parallel. Is
there a situation where this could lead to any improvement in the end?

  parent reply	other threads:[~2024-03-07  9:34 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-20  9:35 [Bug rtl-optimization/101523] New: " krebbel at gcc dot gnu.org
2021-07-20  9:41 ` [Bug rtl-optimization/101523] " krebbel at gcc dot gnu.org
2021-07-20  9:42 ` krebbel at gcc dot gnu.org
2021-07-20 21:27 ` segher at gcc dot gnu.org
2024-02-24  5:45 ` krebbel at gcc dot gnu.org
2024-02-25 10:53 ` segher at gcc dot gnu.org
2024-02-25 15:06 ` segher at gcc dot gnu.org
2024-03-02 18:43 ` sarah.kriesch at opensuse dot org
2024-03-02 21:04 ` sjames at gcc dot gnu.org
2024-03-03 19:32 ` segher at gcc dot gnu.org
2024-03-04  8:18 ` krebbel at gcc dot gnu.org
2024-03-04 16:31 ` segher at gcc dot gnu.org
2024-03-04 16:49 ` sarah.kriesch at opensuse dot org
2024-03-04 21:26 ` segher at gcc dot gnu.org
2024-03-05  7:31 ` krebbel at gcc dot gnu.org
2024-03-05 10:36 ` sarah.kriesch at opensuse dot org
2024-03-06 22:49 ` segher at gcc dot gnu.org
2024-03-06 22:53 ` segher at gcc dot gnu.org
2024-03-06 23:15 ` pinskia at gcc dot gnu.org
2024-03-07  9:26 ` krebbel at gcc dot gnu.org
2024-03-07  9:28 ` krebbel at gcc dot gnu.org
2024-03-07  9:34 ` krebbel at gcc dot gnu.org [this message]
2024-03-07 15:51 ` krebbel at gcc dot gnu.org
2024-03-07 15:52 ` krebbel at gcc dot gnu.org
2024-03-07 16:11 ` segher at gcc dot gnu.org
2024-03-07 16:19 ` segher at gcc dot gnu.org
2024-03-07 16:53 ` pinskia at gcc dot gnu.org
2024-03-07 16:57 ` pinskia at gcc dot gnu.org
2024-03-07 18:15 ` segher at gcc dot gnu.org
2024-03-07 19:42 ` segher at gcc dot gnu.org
2024-03-07 19:45 ` jakub at gcc dot gnu.org
2024-03-07 20:10 ` segher at gcc dot gnu.org
2024-03-07 20:17 ` krebbel at gcc dot gnu.org
2024-03-07 20:53 ` krebbel at gcc dot gnu.org
2024-03-20 11:53 ` [Bug target/101523] " rguenth at gcc dot gnu.org
2024-03-21  7:56 ` segher at gcc dot gnu.org
2024-03-21  8:15 ` rguenth at gcc dot gnu.org
2024-03-21  8:27 ` rguenth at gcc dot gnu.org
2024-03-21 12:57 ` segher at gcc dot gnu.org
2024-03-21 12:58 ` segher at gcc dot gnu.org
2024-03-21 13:15 ` rguenth at gcc dot gnu.org
2024-03-21 13:22 ` rguenth at gcc dot gnu.org
2024-03-22  8:07 ` rguenth at gcc dot gnu.org
2024-03-22  9:41 ` rguenth at gcc dot gnu.org
2024-03-22  9:42 ` sjames at gcc dot gnu.org
2024-03-22  9:42 ` sjames at gcc dot gnu.org
2024-03-22  9:52 ` rguenth at gcc dot gnu.org
2024-03-22 12:17 ` rguenth at gcc dot gnu.org
2024-03-22 12:38 ` rguenth at gcc dot gnu.org
2024-03-27 14:35 ` sarah.kriesch at opensuse dot org
2024-03-27 16:10 ` [Bug rtl-optimization/101523] " cvs-commit at gcc dot gnu.org
2024-03-27 16:53 ` segher at gcc dot gnu.org
2024-03-27 16:55 ` segher at gcc dot gnu.org
2024-04-03 10:58 ` rguenth at gcc dot gnu.org
2024-04-05 11:48 ` segher at gcc dot gnu.org
2024-04-05 12:20 ` rguenth at gcc dot gnu.org
2024-04-10  6:02 ` rguenth at gcc dot gnu.org
2024-04-10 15:51 ` segher at gcc dot gnu.org
2024-04-10 15:57 ` jakub at gcc dot gnu.org
2024-04-10 17:03 ` rguenth at gcc dot gnu.org
2024-04-10 17:45 ` sarah.kriesch at opensuse dot org
2024-05-04  6:00 ` segher at gcc dot gnu.org
2024-05-04 13:14 ` sarah.kriesch at opensuse dot org
2024-05-04 17:30 ` segher at gcc dot gnu.org
2024-05-06  9:21 ` rguenther at suse dot de
2024-05-06  9:40 ` segher at kernel dot crashing.org
2024-05-06  9:42 ` segher at gcc dot gnu.org
2024-05-06  9:46 ` rguenth at gcc dot gnu.org

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