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From: "kristerw at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/106884] ifcombine may move shift so it shifts
 more than bitwidth
Date: Sun, 06 Aug 2023 00:07:37 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106884

--- Comment #6 from Krister Walfridsson <kristerw at gcc dot gnu.org> ---
One more similar case (that may be the same as comment #3):

int g;

void foo(int a, int b, int c, int d, int e)
{
  if ((10 + a) * b)
    {
      g =3D (c || (g >> d)) << 1;
    }
}

In this case, reassoc1 optimizes the IR for
  c || (g >> d)
to do=20
  (c | (g >> d)) !=3D 0
and we are now always doing the shift, even when c is true.=