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From: "aldyh at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/101186] predictable comparison of integer
 variables not folded
Date: Sun, 27 Jun 2021 15:33:18 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101186

--- Comment #5 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
Sorry for the slightly different IL.  I had altered g() to avoid depending =
on
stdio.h:

void g (int a, int b, int x, int y)
{
  int c =3D y;
  if (a !=3D 0)
    c =3D x;
  while (b < 1000)
  // without this loop, jump thread & VRP can remove dead code
    {
      if (a !=3D 0)
        {
          if (c > x)
            unreachable();
        }
      else
        blah();
      b++;
    }
}=