[Bug middle-end/116454] [12/13/14/15 Regression] `*++ptr * 1j` is handled incorrectly with -ffast-math, increments ptr twice

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116454

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Another testcase:
```
static int t = 0;
_Complex float f()
{
        t++;
        return 0;
}
int main() {
        t = 0;
        f() * 1j; // incorrectly invokes f() twice
        if (t != 1)
          __builtin_abort();
}
```