[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 #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
```
inline int func0(int y){
    return -~y;
}
int func2(int y){
    return (~y)/(-(~y));
}
int func2a(int y){
    return (~y)/func0(y);
}
int func1(int y){
    return (~y)/(y+1);
}
```

What is interesting clang is able to handle func2 but not the rest while GCC
currently does not handle any of them (folds -~y early to `y + 1` before `y/-y`
to -y).