[Bug tree-optimization/108757] We do not simplify (a - (N*M)) / N + M -> a / N

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108757

--- 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 = rows_8(D) + 18446744073709551612;
  _15 = _13 / 4;
  doloop.6_5 = _15 + 1;