[Bug tree-optimization/83359] New: [8 Regression] ICE in expand_LOOP_DIST_ALIAS, at internal-fn.c:2362

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83359

            Bug ID: 83359
           Summary: [8 Regression] ICE in expand_LOOP_DIST_ALIAS, at
                    internal-fn.c:2362
           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-alpha20171126 snapshot (r255155) ICEs when compiling the following
snippet w/ -O3 (-Ofast) -floop-parallelize-all -ftree-parallelize-loops=2:

int uw, m0, wy;

void
bp (int jf, int lz)
{
  int *qu = &uw;
  int *c5 = &jf;

  for (uw = 0; uw < 1; ++uw)
    qu = &jf;

  while (m0 < 10)
    {
      for (m0 = 0; m0 < 1; ++m0)
        if (jf == 0)
          while (jf < 1)
            ++jf;
        else
          while (jf < 1)
            {
              qu = &lz;
              ++jf;
            }
      ++m0;
    }

  for (;;)
    for (wy = 0; wy < 2; ++wy)
      {
        if (*qu != 0)
          uw = *c5;

        c5 = &m0;
        lz = 0;
      }
}

% powerpc-e300c3-linux-gnu-gcc-8.0.0-alpha20171126 -O3 -floop-parallelize-all
-ftree-parallelize-loops=2 -c -w drtdvf1q.c                                     
during RTL pass: expand
drtdvf1q.c: In function 'bp':
drtdvf1q.c:4:1: internal compiler error: in expand_LOOP_DIST_ALIAS, at
internal-fn.c:2362
 bp (int jf, int lz)
 ^~
0x9b232a expand_LOOP_DIST_ALIAS
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-8.0.0_alpha20171126/work/gcc-8-20171126/gcc/internal-fn.c:2362
0x724bd7 expand_call_stmt
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-8.0.0_alpha20171126/work/gcc-8-20171126/gcc/cfgexpand.c:2584
0x724bd7 expand_gimple_stmt_1
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-8.0.0_alpha20171126/work/gcc-8-20171126/gcc/cfgexpand.c:3607
0x724bd7 expand_gimple_stmt
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-8.0.0_alpha20171126/work/gcc-8-20171126/gcc/cfgexpand.c:3773
0x726ddf expand_gimple_basic_block
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-8.0.0_alpha20171126/work/gcc-8-20171126/gcc/cfgexpand.c:5772
0x72cf2f execute
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-8.0.0_alpha20171126/work/gcc-8-20171126/gcc/cfgexpand.c:6373