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From: "tnfchris at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/114860] [14/15 regression] [aarch64] 511.povray regresses by ~5.5% with -O3 -flto -march=native -mcpu=neoverse-v2 since r14-10014-ga2f4be3dae04fa
Date: Wed, 22 May 2024 11:36:12 +0000	[thread overview]
Message-ID: <bug-114860-4-PYIMN5sg1T@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114860-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114860

--- Comment #9 from Tamar Christina <tnfchris at gcc dot gnu.org> ---
(In reply to prathamesh3492 from comment #8)
> Hi Tamar,
> Using -falign-loops=5 indeed brings back the performance.
> The adrp instruction has same address (0x4ae784) by setting -falign-loops=5
> (which reduces misalignment to 4) with/without a2f4be3dae0. So I guess this
> is really code-alignment issue ?
> 

Indeed, we don't aggressively align loops if they require too much padding to
not bloat the binaries too much.  That's why sometimes you just get unlucky and
the hot loop gets misaligned.

      parent reply	other threads:[~2024-05-22 11:36 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-26  6:25 [Bug target/114860] New: [aarch64] 511.povray regresses by ~5.5% with -O3 -flto -march=native -mcpu=neoverse-v2 prathamesh3492 at gcc dot gnu.org
2024-04-26 14:27 ` [Bug target/114860] [14/15 regression] [aarch64] 511.povray regresses by ~5.5% with -O3 -flto -march=native -mcpu=neoverse-v2 since r14-10014-ga2f4be3dae04fa rguenth at gcc dot gnu.org
2024-04-26 14:30 ` tnfchris at gcc dot gnu.org
2024-04-26 14:46 ` tnfchris at gcc dot gnu.org
2024-05-01  6:22 ` tnfchris at gcc dot gnu.org
2024-05-03 10:45 ` prathamesh3492 at gcc dot gnu.org
2024-05-03 21:20 ` pinskia at gcc dot gnu.org
2024-05-07  7:45 ` rguenth at gcc dot gnu.org
2024-05-16 17:17 ` tnfchris at gcc dot gnu.org
2024-05-22 11:27 ` prathamesh3492 at gcc dot gnu.org
2024-05-22 11:36 ` tnfchris at gcc dot gnu.org [this message]

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