[Bug tree-optimization/108397] Missed optimization with [0, 0][-1U,-1U] range arithmetics

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108397

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I have a patch to fix the testcase in comment #2.

After that patch we have:
```
  _1 = o_10(D) == 0;
  _2 = (long long int) _1;
  _3 = -_2;
  t1_11 = (long long unsigned int) _3;
  _4 = t1_11 == 18446744073709551615;
  _5 = (long long int) _4;
  _6 = -_5;
  t2_12 = (long long unsigned int) _6;
  _7 = t1_11 <= t2_12;
  _8 = (long long int) _7;
  _9 = -_8;
  t3_13 = (long long unsigned int) _9;
```

Forwprop will not change _4 to _1 though. because t1_11 is used twice.