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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/108757] We do not simplify (a - (N*M)) / N +
 M -> a / N
Date: Mon, 13 Feb 2023 21:01:23 +0000
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X-Bugzilla-Component: tree-optimization
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108757

--- Comment #19 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note in the loop case we know it does not wrap because there is a check
already:
  <bb 2> [local count: 118111600]:
  if (rows_8(D) > 3)
    goto <bb 5>; [89.00%]
  else
    goto <bb 4>; [11.00%]

  <bb 5> [local count: 105119324]:
  _13 =3D rows_8(D) + 18446744073709551612;
  _15 =3D _13 / 4;
  doloop.6_5 =3D _15 + 1;=