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From: "aros at gmx dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug ipa/96337] [10/11 Regression] GCC 10.2: twice as slow for -O2
 -march=x86-64 vs. GCC 9.3/8.4
Date: Wed, 29 Jul 2020 07:56:17 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96337

--- Comment #12 from Artem S. Tashkinov <aros at gmx dot com> ---
Michael has admitted that might be a specific CPU relate regression:

> Been running some more tests today:
> - Tried on a i9-10980XE Cascade Lake and Cascade Lake Xeon systems and di=
d not reproduce...
> - I went back to the i9-10900K and picked just a few of the tests where i=
t was impacted the hardest, but then surprisingly the results were similar =
that run.

Source:
https://www.phoronix.com/forums/forum/software/programming-compilers/119678=
9-gcc-benchmarks-at-varying-optimization-levels-with-core-i9-10900k-show-an=
-unexpected-surprise?p=3D1197196#post1197196

The plot thickens.=