[Bug ipa/65270] [5 regression] ICF needs to match TYPE attributes on memory accesses

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65270

--- Comment #10 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
Hi,
while looking for a testcase that would trigger with tree-tail-merge (because
gimple-fold seems to also miss MEM_REF merging) I noticed following oddity:

struct a 
{
  int a[100000];
};
typedef struct a b __attribute__ ((aligned (32)));
typedef struct a c __attribute__ ((aligned (8)));
typedef struct a d __attribute__ ((aligned (32)));

__attribute__ ((used))
t(b *a, int aligned, b *d)
{
  int i,v;
        c *ptr = a;
  for (i=0;i<100000;i++)
    {
        ptr->a[i]++;
    }
}
main()
{
}

here the loop gets vectorized with assumed alignmen 32.
Changing declaretion to:
t(c *a, int aligned, b *d)
produces correct 8 byte alignment loop.
Alignment of the type of variable A shall not be used.