[Bug target/72749] New: [7 Regression] ICE: verify_flow_info failed (error: wrong amount of branch edges after conditional jump in bb 5) w/ -O2 -fsched2-use-superblocks

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72749

            Bug ID: 72749
           Summary: [7 Regression] ICE: verify_flow_info failed (error:
                    wrong amount of branch edges after conditional jump in
                    bb 5) w/ -O2 -fsched2-use-superblocks
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---
            Target: powerpc-*-linux-gnu*

gcc-7.0.0-alpha20160724 fails to compile the following reduced testcase for
32-bit BE powerpc target w/ -O2 (-O3, -Ofast) -fsched2-use-superblocks
-mcpu=power7 (power8, powerpc64le):

int as;

void
ji (int *x4)
{
  if (0)
    {
      unsigned int pv;

      while (as < 0)
        {
          for (*x4 = 0; *x4 < 1; ++(*x4))
yj:
            x4 = (int *)&pv;
          ++as;
        }
    }
  goto yj;
}

% powerpc-e300c3-linux-gnu-gcc-7.0.0-alpha20160724 -c -O2
-fsched2-use-superblocks dao4bxj1.c
(or
% powerpc-e500v2-linux-gnuspe-gcc-7.0.0-alpha20160724 -c -mcpu=power7 -Ofast
-fsched2-use-superblocks -w dao4bxj1.c)
dao4bxj1.c: In function 'ji':
dao4bxj1.c:19:1: error: wrong amount of branch edges after conditional jump in
bb 5
 }
 ^
dao4bxj1.c:19:1: internal compiler error: verify_flow_info failed