[Bug rtl-optimization/85899] New: ICE in find_fallthru_edge_from, at haifa-sched.c:8059

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85899

            Bug ID: 85899
           Summary: ICE in find_fallthru_edge_from, at haifa-sched.c:8059
           Product: gcc
           Version: unknown
            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: ---
            Target: powerpc-*-linux-gnu, powerpcspe-*-linux-gnu

gcc-9.0.0-alpha20180520 snapshot (r260425) ICEs when compiling the following
snippet w/ -O1 (-O2, -O3, -Ofast) -fschedule-insns -fsel-sched-pipelining
-fsel-sched-pipelining-outer-loops -fselective-scheduling
-ftree-parallelize-loops=2 -funroll-all-loops -fwrapv --param
parloops-schedule=dynamic (=guided, =runtime):

int
a4 (int wa, int oe)
{
  while (wa < 1)
    {
      oe *= wa / 0xffffffff00000001;
      ++wa;
    }

  return oe;
}

% powerpc-e300c3-linux-gnu-gcc-9.0.0-alpha20180520 -O1 -fschedule-insns
-fsel-sched-pipelining -fsel-sched-pipelining-outer-loops
-fselective-scheduling -ftree-parallelize-loops=2 -funroll-all-loops -fwrapv
--param parloops-schedule=dynamic -c xfyr4jfp.c
during RTL pass: sched1
xfyr4jfp.c: In function 'a4._loopfn.0':
xfyr4jfp.c:4:9: internal compiler error: in find_fallthru_edge_from, at
haifa-sched.c:8059
   while (wa < 1)
         ^
0x14430f1 find_fallthru_edge_from(basic_block_def*)
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/haifa-sched.c:8059
0xc199dd in_fallthru_bb_p
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sel-sched.c:608
0xc199dd extract_new_fences_from
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sel-sched.c:680
0xc199dd calculate_new_fences
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sel-sched.c:7429
0xc199dd sel_sched_region_2
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sel-sched.c:7505
0xc19e61 sel_sched_region_1
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sel-sched.c:7546
0xc1b455 sel_sched_region(int)
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sel-sched.c:7647
0xc1bda9 run_selective_scheduling()
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sel-sched.c:7733
0xbf2824 rest_of_handle_sched
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sched-rgn.c:3718
0xbf2824 execute
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-9.0.0_alpha20180520/work/gcc-9-20180520/gcc/sched-rgn.c:3828