[Bug tree-optimization/82321] New: [8 Regression] ICE in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:707

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82321

            Bug ID: 82321
           Summary: [8 Regression] ICE in check_loop_closed_ssa_use, at
                    tree-ssa-loop-manip.c:707
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-8.0.0-alpha20170924 snaphost (r253127) ICEs when compiling the following
snippet w/ -O2 -floop-nest-optimize:

int y8;

void
dm (int io)
{
  if (y8 != 0)
    {
      int pu = 1;

      while (io < 2)
        {
          int xo = (pu != 0) ? y8 : 0;

          while (y8 != 0)
            if (xo != 0)
              {
 gi:
                xo = &io;
                pu = 0;
              }
        }
    }

  if (io != 0)
    {
      y8 = 1;
      while (y8 != 0)
        if (io / !y8 != 0)
          y8 = 0;

      goto gi;
    }
}

% gcc-8.0.0-alpha20170924 -O2 -floop-nest-optimize -w -c r9nismdn.c
during GIMPLE pass: graphite
r9nismdn.c: In function 'dm':
r9nismdn.c:4:1: internal compiler error: in check_loop_closed_ssa_use, at
tree-ssa-loop-manip.c:707
 dm (int io)
 ^~