[Bug rtl-optimization/78625] New: [7 Regression] ICE in invert_tree_comparison, at fold-const.c:2483 w/ -O1 -Wmaybe-uninitialized

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78625

            Bug ID: 78625
           Summary: [7 Regression] ICE in invert_tree_comparison, at
                    fold-const.c:2483 w/ -O1 -Wmaybe-uninitialized
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-7.0.0-alpha20161127 snapshot fails when compiling the following snippet w/
-O1 (or -Og) -Wmaybe-uninitialized:

int
pu (int xl, int ee)
{
  int db = xl % 1;

  if (db < 1)
    {
      xl = (db < 1);

      if ((xl & ee) == 0)
        db = ee;
      if (db == 0)
        {
          int vf;

          do
            {
              if (ee != 1)
                vf += ee;
            }
          while (vf < 0);
        }
    }

  return db;
}

% gcc-7.0.0-alpha20161127 -O1 -Wmaybe-uninitialized -c kuhp4o2f.c
kuhp4o2f.c: In function 'pu':
kuhp4o2f.c:2:1: internal compiler error: in invert_tree_comparison, at
fold-const.c:2483
 pu (int xl, int ee)
 ^~

According to the backtrace, this is likely a regression from r242639.