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From: "amonakov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/111683] [11/12/13/14 Regression] Incorrect answer
 when using SSE2 intrinsics with -O3
Date: Wed, 04 Oct 2023 16:56:29 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111683

Alexander Monakov <amonakov at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |amonakov at gcc dot gnu.org

--- Comment #3 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
This is predcom. It's easier to see what's going wrong with

#pragma GCC unroll 99

added to the innermost loop so it's unrolled at -O2 and comparing

g++ -O2 -fpredictive-commoning --param=3Dmax-unroll-times=3D1

vs. plain g++ -O2 (or diffing 'pcom' dump against the preceding pass).=