[Bug tree-optimization/84584] New: [8 Regression] [graphite] ICE: Segmentation fault (in dominated_by_p)

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84584

            Bug ID: 84584
           Summary: [8 Regression] [graphite] ICE: Segmentation fault (in
                    dominated_by_p)
           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-alpha20180225 snapshot (r257975) ICEs when compiling the following
snippet w/ -O1 (-O2, -O3, -Ofast) -fgraphite-identity -fno-tree-loop-im:

int q3, w1;

void
bw (int b8)
{
  const int sd = 2;
  int mc;

  for (mc = 0; mc < sd; ++mc)
    {
 ik:
      for (w1 = 0; w1 < sd; ++w1)
        ++b8;
    }

  for (q3 = 0; q3 < sd; ++q3)
    {
    }

  goto ik;
}

% gcc-8.0.0-alpha20180225 -O1 -fgraphite-identity -fno-tree-loop-im -c
w8fja3ap.c
during GIMPLE pass: graphite
w8fja3ap.c: In function 'bw':
w8fja3ap.c:4:1: internal compiler error: Segmentation fault
 bw (int b8)
 ^~
0xc9d7bf crash_signal
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/toplev.c:325
0x8f73e9 dominated_by_p(cdi_direction, basic_block_def const*, basic_block_def
const*)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/dominance.c:1118
0x1465a71 bb_in_region
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/sese.h:124
0x1465a71 bb_in_sese_p
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/sese.h:134
0x1465a71 loop_in_sese_p
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/sese.h:159
0x1465a71 add_loop_constraints
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/graphite-sese-to-poly.c:747
0x14660e5 build_iteration_domains
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/graphite-sese-to-poly.c:852
0x146667f build_poly_scop(scop*)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/graphite-sese-to-poly.c:1215
0x1457f40 graphite_transform_loops()
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/graphite.c:406
0x1458470 graphite_transforms
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/graphite.c:475
0x1458470 execute
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180225/work/gcc-8-20180225/gcc/graphite.c:552