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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/95821] New: Failure to optimize strchr to use
 memchr for string constant
Date: Mon, 22 Jun 2020 17:07:10 +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=3D95821

            Bug ID: 95821
           Summary: Failure to optimize strchr to use memchr for string
                    constant
           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: ---

auto f(char c)
{
    return strchr("123", c);
}

This can be optimized to `return memchr("123", c, 4)`. This transformation =
is
done by LLVM, but not by GCC.=