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From: "segher 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: Wed, 06 Mar 2024 22:49:25 +0000	[thread overview]
Message-ID: <bug-101523-4-BejsXsvf3N@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 #16 from Segher Boessenkool <segher at gcc dot gnu.org> ---
(In reply to Andreas Krebbel from comment #14)
> If my analysis from comment #1 is correct, combine does superfluous steps
> here. Getting rid of this should not cause any harm, but should be
> beneficial for other targets as well. I agree that the patch I've proposed
> is kind of a hack. Do you think this could be turned into a proper fix?

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.

  parent reply	other threads:[~2024-03-06 22:49 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 [this message]
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
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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