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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/100393] [9/10/11/12 Regression] Very slow
 compilation of switch statement with thousands of cases
Date: Mon, 03 May 2021 13:58:48 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D100393

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
I guess that's already done, so it has to be fixed in other ways, like by
keeping the partial sum when decreasing the size in

      for (unsigned j =3D 0; j < i; j++)
        {
          if (min[j].m_count + 1 < min[i].m_count
              && can_be_handled (clusters, j, i - 1))
            min[i] =3D min_cluster_item (min[j].m_count + 1, j, INT_MAX);
        }

maybe "simply" binary search j in [0, i-1] rather than doing a linear
search here.=