[Bug tree-optimization/114999] A few missing optimizations due to `a - b` and `b - a` not being detected as negatives of each other

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114999

--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
```
float f(float a, float b, float x)
{
  x = a - b;
  float t = 0;
  t = t - x;
  return t/x;
}
```
! HONOR_NANS (type)  && ! HONOR_INFINITIES (type)



```
int f(int a, int b, int A)
{
  A = ~A;
  int t = 0;
  t = t - A;
  return A != 0 ? A : t;
}
```

Is not optimized at -O1 until phiopt3 .