[Bug middle-end/79386] New: [7 Regression] ICE: segmentation fault in cprop w/ -O2 on 32-bit BE powerpc

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79386

            Bug ID: 79386
           Summary: [7 Regression] ICE: segmentation fault in cprop w/ -O2
                    on 32-bit BE powerpc
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---
            Target: powerpc-*-linux-gnu*

At least gcc-7.0.0-alpha20170129 and gcc-7.0.0-alpha20170205 snapshots ICE when
compiling the following snippet for 32-bit BE powerpc targets w/ -O2:

int fy, er;

int
ot (int dh)
{
  int t5;
  int *ge, *ys;

  if (er == 0)
  {
    t5 = 0;
    ys = &er;
    ge = &er;
  }
  else
  {
    int ay;

    t5 = 1;
    for (ay = 0; ay < 9; ++ay)
      t5 *= 3;
    ys = t5;
    ge = &dh;
  }

  *ys = t5 < 3;
  if (*ys != 0)
  {
    int sr;

    er += (fy != 0) ? fy : 1;
    if (sr != 0 || dh != 0)
      *ge = 0;
    if (er >= 0)
    {
      if (sr != 0)
        sr = dh;
      if (*ge / sr != 0)
        for (;;)
        {
        }
    }
  }

  return er * (fy != 0 && *ge != 0);
}

% powerpc-e300c3-linux-gnu-gcc-7.0.0-alpha20170205 -O2 -w -c rxffdvao.c
rxffdvao.c: In function 'ot':
rxffdvao.c:46:1: internal compiler error: Segmentation fault
 }
 ^
0x2ed19bc7d19 crash_signal
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-7.0.0_alpha20170205/work/gcc-7-20170205/gcc/toplev.c:333
0x2ed1a25f149 find_bypass_set
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-7.0.0_alpha20170205/work/gcc-7-20170205/gcc/cprop.c:1474
0x2ed1a25f149 bypass_block
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-7.0.0_alpha20170205/work/gcc-7-20170205/gcc/cprop.c:1597
0x2ed1a25f149 bypass_conditional_jumps
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-7.0.0_alpha20170205/work/gcc-7-20170205/gcc/cprop.c:1731
0x2ed1a25f149 one_cprop_pass
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-7.0.0_alpha20170205/work/gcc-7-20170205/gcc/cprop.c:1874
0x2ed1a25f149 execute_rtl_cprop
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-7.0.0_alpha20170205/work/gcc-7-20170205/gcc/cprop.c:1918
0x2ed1a25f149 execute
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-7.0.0_alpha20170205/work/gcc-7-20170205/gcc/cprop.c:1956