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From: "gabravier at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/96707] New: Failure to optimize right
 shift+unsigned compare of two variables optimally
Date: Wed, 19 Aug 2020 13:03:08 +0000
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X-Bugzilla-Product: gcc
X-Bugzilla-Component: tree-optimization
X-Bugzilla-Version: 11.0
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96707

            Bug ID: 96707
           Summary: Failure to optimize right shift+unsigned compare of
                    two variables optimally
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

bool f(unsigned x, unsigned y)
{
    return (x >> y) <=3D x;
}

This can be optimized to `return true;`. This transformation is done by LLV=
M,
but not by GCC.=