[Bug tree-optimization/60000] New: GCC trunk build failure caused by the vectorizer.

["congh at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60000

            Bug ID: 60000
           Summary: GCC trunk build failure caused by the vectorizer.
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: congh at gcc dot gnu.org

GCC fails to build the following code with flags

g++ -O2 -fno-tree-vrp -ftree-vectorize foo.C


//foo.C:

void foo(bool* a, int* b)
{
  for(int i = 0; i < 1000; ++i)
  {
    a[i] = i % 2;
    b[i] = i % 3;
  }
}



The output message from GCC:


 void foo(bool*, int*)
Analyzing compilation unit
Performing interprocedural optimizations
 <*free_lang_data> <visibility> <early_local_cleanups> <*free_inline_summary>
<whole-program> <profile_estimate> <devirt> <cp> <inline> <pure-const>
<static-var>Assembling functions:
 void foo(bool*, int*)foo.C:3:3: note: loop vectorized
foo.C:3:3: note: loop versioned for vectorization because of possible aliasing

foo.C: In function âvoid foo(bool*, int*)â:
foo.C:1:6: internal compiler error: in vect_get_vec_def_for_operand, at
tree-vect-stmts.c:1449
 void foo(bool* a, int* b)
      ^
0xf82cd5 vect_get_vec_def_for_operand(tree_node*, gimple_statement_base*,
tree_node**)
    ../../gcc/gcc/tree-vect-stmts.c:1449
0xf83194 vect_get_vec_defs(tree_node*, tree_node*, gimple_statement_base*,
vec<tree_node*, va_heap, vl_ptr>*, vec<tree_node*, va_heap, vl_ptr>*,
_slp_tree*, int)
    ../../gcc/gcc/tree-vect-stmts.c:1634
0xf8e060 vectorizable_operation
    ../../gcc/gcc/tree-vect-stmts.c:4785
0xf94be4 vect_transform_stmt(gimple_statement_base*, gimple_stmt_iterator*,
bool*, _slp_tree*, _slp_instance*)
    ../../gcc/gcc/tree-vect-stmts.c:6959
0xfa8f0e vect_transform_loop(_loop_vec_info*)
    ../../gcc/gcc/tree-vect-loop.c:6046
0xfbe02a vectorize_loops()
    ../../gcc/gcc/tree-vectorizer.c:476
0xec9b80 tree_loop_vectorize
    ../../gcc/gcc/tree-ssa-loop.c:154
0xec9c0a execute
    ../../gcc/gcc/tree-ssa-loop.c:189
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