[Bug tree-optimization/69358] New: [6 regression] internal compiler error: in equal_mem_array_ref_p

[ienkovich at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69358

            Bug ID: 69358
           Summary: [6 regression] internal compiler error: in
                    equal_mem_array_ref_p
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ienkovich at gcc dot gnu.org
  Target Milestone: ---

I see it starting from r232508.

>cat test.i
int a, b;
int c[1][4];
int fn1() {
  int i, j, d;
  j = 0;
  for (; j < 4; j++)
    for (; i; i++)
      c[i][j] = a;
  for (; i; i++) {
    j = 0;
    for (; j < 2; j++)
      d = c[i][d] = c[i][j];
    j = 0;
    for (; j < 4; j++)
      b = a;
  }
}
>gcc -O2 -S test.i
test.i: In function 'fn1':
test.i:3:5: internal compiler error: in equal_mem_array_ref_p, at
tree-ssa-scopedtables.c:271
 int fn1() {
     ^~~

0x1007f55 equal_mem_array_ref_p
       
/export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-scopedtables.c:271
0x10081d6 hashable_expr_equal_p
       
/export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-scopedtables.c:310
0x10097b3 expr_elt_hasher::equal(expr_hash_elt* const&, expr_hash_elt* const&)
       
/export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-scopedtables.c:747
0xf47a36 hash_table<expr_elt_hasher,
xcallocator>::find_slot_with_hash(expr_hash_elt* const&, unsigned int,
insert_option)
        /export/users/ienkovic/issues/avx-512/gcc/gcc/hash-table.h:873
0xf47bc1 hash_table<expr_elt_hasher, xcallocator>::find_slot(expr_hash_elt*
const&, insert_option)
        /export/users/ienkovic/issues/avx-512/gcc/gcc/hash-table.h:414
0xf46e4e lookup_avail_expr
        /export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-dom.c:2018
0xf45677 eliminate_redundant_computations
        /export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-dom.c:1460
0xf46763 optimize_stmt
        /export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-dom.c:1863
0xf4534a dom_opt_dom_walker::before_dom_children(basic_block_def*)
        /export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-dom.c:1368
0x16bad82 dom_walker::walk(basic_block_def*)
        /export/users/ienkovic/issues/avx-512/gcc/gcc/domwalk.c:265
0xf4390e execute
        /export/users/ienkovic/issues/avx-512/gcc/gcc/tree-ssa-dom.c:613
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