[Bug tree-optimization/88069] New: [9 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.c:709

["asolokha at gmx dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88069

            Bug ID: 88069
           Summary: [9 Regression] ICE in check_loop_closed_ssa_def, at
                    tree-ssa-loop-manip.c:709
           Product: gcc
           Version: 9.0
            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-9.0.0-alpha20181111 snapshot (r266019) ICEs when compiling the following
snippet w/ -O1 (-O2, -O3, -Ofast) -ftree-pre -ftree-vectorize -fno-tree-pta:

void
qf (void);

void
mr (short int db)
{
  int vq;
  short int *lp = &db;

  for (vq = 0; vq < 1; ++vq)
    qf ();

  while (*lp < 2)
    {
      *lp = db;
      lp = (short int *) &vq;
      ++*lp;
    }
}

% gcc-9.0.0-alpha20181111 -O1 -ftree-pre -ftree-vectorize -fno-tree-pta -c
n5bt3ltb.c
during GIMPLE pass: ch_vect
n5bt3ltb.c: In function 'mr':
n5bt3ltb.c:5:1: internal compiler error: in check_loop_closed_ssa_def, at
tree-ssa-loop-manip.c:709
    5 | mr (short int db)
      | ^~
0x6a0e44 check_loop_closed_ssa_def
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181111/work/gcc-9-20181111/gcc/tree-ssa-loop-manip.c:709
0xe31ec8 check_loop_closed_ssa_bb
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181111/work/gcc-9-20181111/gcc/tree-ssa-loop-manip.c:735
0xe34056 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181111/work/gcc-9-20181111/gcc/tree-ssa-loop-manip.c:760
0xe34056 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181111/work/gcc-9-20181111/gcc/tree-ssa-loop-manip.c:744
0xc04b34 execute_function_todo
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181111/work/gcc-9-20181111/gcc/passes.c:1943
0xc058de execute_todo
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181111/work/gcc-9-20181111/gcc/passes.c:1979