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From: "pheeck at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/114414] New: [14 Regression] 15-18% exec time slowdown of 433.milc on Zen2
Date: Thu, 21 Mar 2024 10:35:25 +0000	[thread overview]
Message-ID: <bug-114414-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114414

            Bug ID: 114414
           Summary: [14 Regression] 15-18% exec time slowdown of 433.milc
                    on Zen2
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: missed-optimization, needs-bisection
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pheeck at gcc dot gnu.org
            Blocks: 26163
  Target Milestone: ---
              Host: x86_64-linux
            Target: x86_64-linux

As seen here

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=685.70.0

there is an 18% slowdown of the 433.milc SPEC 2006 benchmark between commits

g:74e8cc28eda9b1d7
g:81ee1298b47d3f3b

The compilation options are -O2 -flto PGO. The CPU is AMD Zen2. I've replicated
this slowdown on another Zen2 machine. There the slowdown was only 15%.

Btw here is the same plot but with comparisons to GCC13 and GCC12

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=685.70.0&plot.6=921.70.0&plot.7=762.70.0


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=26163
[Bug 26163] [meta-bug] missed optimization in SPEC (2k17, 2k and 2k6 and 95)

             reply	other threads:[~2024-03-21 10:35 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-21 10:35 pheeck at gcc dot gnu.org [this message]
2024-03-21 10:36 ` [Bug target/114414] " pheeck at gcc dot gnu.org
2024-03-22 12:34 ` law at gcc dot gnu.org
2024-03-27  8:02 ` rguenth at gcc dot gnu.org
2024-03-28 10:33 ` [Bug target/114414] " pheeck at gcc dot gnu.org
2024-03-28 12:12 ` pheeck at gcc dot gnu.org

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