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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/104049] [12 Regression] vec_select to subreg
 lowering causes superfluous moves
Date: Mon, 17 Jan 2022 02:20:39 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104049

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-01-17
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=3D104039
   Target Milestone|---                         |12.0
     Ever confirmed|0                           |1
           Keywords|                            |ra

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This might be the same issue as PR 104039 really, though there we have a
paradoxical subreg.

The problem is the register allocator really really does not handle subreg =
in a
decent way.=