[Bug tree-optimization/92347] [10 Regression] ICE in vect_get_vec_def_for_operand_1, at tree-vect-stmts.c:1537

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92347

--- Comment #2 from Arseny Solokha <asolokha at gmx dot com> ---
I believe I have something that is a different manifestation of the same
problem.

1. gcc-10.0.0-alpha20191103 snapshot (r277758) ICEs when compiling the
following testcase reduced from gcc/testsuite/gcc.dg/vect/vect-simd-clone-11.c
w/ -mavx2 -O1 -fopenmp -ftree-loop-vectorize -ftree-parallelize-loops=2
-fno-tree-loop-ivcanon:

#pragma omp declare simd linear (yu : 6)
int __attribute__ ((noinline))
ms (int yu)
{
  return yu;
}

void
fm (int *kq)
{
  int v1 = 0, r5 = 1;

  while (v1 < 200)
    {
      kq[v1] = ms (r5 * 2);
      r5 += 3;
      ++v1;
    }
}

% x86_64-unknown-linux-gnu-gcc-10.0.0-alpha20191103 -mavx2 -O1 -fopenmp
-ftree-loop-vectorize -ftree-parallelize-loops=2 -fno-tree-loop-ivcanon -c
ax2wgtfe.c
ax2wgtfe.c: In function 'fm._loopfn.0':
ax2wgtfe.c:13:9: error: definition in block 13 does not dominate use in block
22
   13 |   while (v1 < 200)
      |         ^
for SSA_NAME: _84 in statement:
_147 = _84 + 1;
during GIMPLE pass: vect
ax2wgtfe.c:13:9: internal compiler error: verify_ssa failed
0xe4094c verify_ssa(bool, bool)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/tree-ssa.c:1208
0xbab70c execute_function_todo
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/passes.c:1990
0xbac460 do_per_function
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/passes.c:1638
0xbac460 execute_todo
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/passes.c:2037

2. When compiling the following testcase w/ -O1 -ftree-loop-vectorize:

short int zb;

void
gs (void)
{
  while (zb < 1)
    {
      int at;

      zb %= 1;

      for (at = 0; at < 56; ++at)
        zb += zb;

      ++zb;
    }
}

% x86_64-unknown-linux-gnu-gcc-10.0.0-alpha20191103 -O1 -ftree-loop-vectorize
-c klumnm2e.c
klumnm2e.c: In function 'gs':
klumnm2e.c:4:1: error: excess use operand for statement
    4 | gs (void)
      | ^~
0
_7 = 0 + 1;
during GIMPLE pass: vect
klumnm2e.c:4:1: internal compiler error: verify_ssa failed
0xe4094c verify_ssa(bool, bool)
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/tree-ssa.c:1208
0xbab70c execute_function_todo
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/passes.c:1990
0xbac460 do_per_function
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/passes.c:1638
0xbac460 execute_todo
       
/var/tmp/portage/sys-devel/gcc-10.0.0_alpha20191103/work/gcc-10-20191103/gcc/passes.c:2037