[Bug rtl-optimization/31889] compiler misses opportunity to combine multiple identical function return paths

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=31889

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #5)
> Except it is no longer fixed by that.  That broke in GCC 10.

It broke in GCC 10 because we now have:
```
  if (_10 < _12)
    goto <bb 3>; [1.04%]
  else
    goto <bb 4>; [98.96%]

  <bb 3> [local count: 11166912]:
  d1 ={v} {CLOBBER(eol)};
  d2 ={v} {CLOBBER(eol)};
  goto <bb 8>; [100.00%]

  <bb 4> [local count: 1062574912]:
  if (_10 > _12)
    goto <bb 5>; [34.00%]
  else
    goto <bb 6>; [66.00%]

  <bb 5> [local count: 361275474]:
  d1 ={v} {CLOBBER(eol)};
  d2 ={v} {CLOBBER(eol)};
  goto <bb 8>; [100.00%]
```
Which can be figured out is the same via `code hoisting` pass.