[Bug tree-optimization/83914] [8 Regression] ice in vect_is_simple_use with -O3

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83914

--- Comment #2 from David Binderman <dcb314 at hotmail dot com> ---
Reduced code is

struct {
  int *a[8]
} * b;
c;
*d;
e() {
  int f;
  for (; f; b = d, f--) {
    d = b + 1;
    c = 8;
    for (; c; c--)
      b->a[c] = d;
  }
}