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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/19832] don't remove an if when we know the
 value is the same as with the if (subtraction)
Date: Sat, 06 May 2023 21:15:22 +0000
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X-Bugzilla-Component: tree-optimization
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X-Bugzilla-Keywords: missed-optimization
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D19832

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |pinskia at gcc dot =
gnu.org
             Status|NEW                         |ASSIGNED

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I will implement this match pattern since that is all that is needed now wi=
th
phiopt using match.

Something like:
(simplify
 (cond (ne @0 @1) (minus@2 @0 @1) (zerop@3))
 (@2))
Should work.

Note there might be need to be a check for HONOR_SIGNED_ZEROS and maybe
HONOR_NANS missing.=