[Bug tree-optimization/105198] [11/12 Regression] Wrong code for C loop (GCC 12 -O2, GCC 11 -O3)

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105198

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Reduced testcase for the predictive commoning issue, fails with -O3 or
-O2 -fno-tree-pre -fpredictive-commoning

static  __attribute__ ((noipa)) void
next_set(int *x, int n, int k)
{
  int j, tmp;
  j = k - 1;
  tmp = x[j]++;
  while(j > 0 && x[j] >= n - (k - 1 -j))
    {
      j--;
      x[j]++;
      tmp = x[j];
    }
  if (tmp != 2 || j != 1 || x[0] != 0 || x[1] != 2 || x[2] != 5)
    __builtin_abort ();
}

int main()
{
  int x[3] = {0, 1, 4};
  next_set(x, 5, 3);
  return 0;
}