[Bug rtl-optimization/81791] [8 Regression] ICE in cfg_layout_redirect_edge_and_branch, at cfgrtl.c:4422

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81791

Arseny Solokha <asolokha at gmx dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |asolokha at gmx dot com

--- Comment #3 from Arseny Solokha <asolokha at gmx dot com> ---
int sa, wy;

void
v0 (int *yg, int dq)
{
  int mc = 0;

  while (dq < 1)
    {
      while (dq < 0)
        {
        }

      while (wy != 0)
        {
 x6:
          *yg = mc;
          for (sa = 0; sa < 2; ++sa)
            wy = 1;
          if (dq != 0)
            *yg = 0;
          ++mc;
        }
    }

  goto x6;
}

% gcc-8.0.0-alpha20171217 -O2 -fmodulo-sched -fno-guess-branch-probability
-fno-tree-scev-cprop -c euvaex6b.c                         
during RTL pass: sms
euvaex6b.c: In function 'v0':
euvaex6b.c:27:1: internal compiler error: in
cfg_layout_redirect_edge_and_branch, at cfgrtl.c:4434
 }
 ^
0x5c8985 cfg_layout_redirect_edge_and_branch
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/cfgrtl.c:4434
0x97d1b8 cfg_layout_redirect_edge_and_branch_force
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/cfgrtl.c:4444
0x9664d3 redirect_edge_and_branch_force(edge_def*, basic_block_def*)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/cfghooks.c:486
0x966ee6 make_forwarder_block(basic_block_def*, bool (*)(edge_def*), void
(*)(basic_block_def*))
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/cfghooks.c:893
0x978a53 create_preheader(loop*, int)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/cfgloopmanip.c:1501
0x978c07 create_preheaders(int)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/cfgloopmanip.c:1552
0xbd4229 apply_loop_flags
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/loop-init.c:64
0xbd4aec loop_optimizer_init(unsigned int)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/loop-init.c:123
0x1492609 sms_schedule
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/modulo-sched.c:1351
0x1494dbf execute
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20171217/work/gcc-8-20171217/gcc/modulo-sched.c:3342

(as of r255766)

I believe it's the same issue.