[Bug tree-optimization/101240] [missed optimization] Transitivity of less-than and less-or-equal

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101240

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
here is a better testcase:
```
int test_array(unsigned (&a)[3]) {
  int t = (a[0]+a[1]+a[2]);
  ALWAYS_TRUE(a[0] < a[1] && a[1] < a[2]);
  return (a[0] < a[2])+t;
}
```
(just to make sure VRP is only dealing with SSA names).

We should be able to optimize the above to just
return a[0]+a[1]+a[2]+1;