[Bug rtl-optimization/110528] selective scheduling seems to go into an infinite loop

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110528

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Here is a testcase which does not go into an infinite loop but takes a little
more than 4 seconds to compile which is a lot:
```
static unsigned short g_231 = 1UL;
void func_61(unsigned p_62) {
  unsigned char g_116 = 0xE3L;
  int l_733;
  int l_661;
  unsigned char l_746;
  for (l_733 = 5; (l_733 >= 1); l_733 -= 1) 
    for (l_746 = 1; (l_746 <= 7); l_746 += 1) 
      for (g_116 = 2; (g_116 <= 7); g_116 += 1) 
        for (l_661 = 6; (l_661 >= 0); l_661 -= 1)
        {
          &g_231;
          (g_231) = (0x84EAL <= p_62);
        }
}

```

This is with `-gstatement-frontiers -O3 -fselective-scheduling2`.
Without `-fselective-scheduling2` GCC compiles this less than a second.