add64 overflow calculation whether mistake？
```C
static inline uint64_t add64(x64emu_t *emu, uint64_t d, uint64_t s)
{
	emu->res.u64 = d + s;
	emu->op1.u64 = d;
	emu->op2.u64 = s;
	emu->df = d_add64;
    return emu->res.u64;
}
```
(x64primop.h)

Here, the result of adding two 64 bits is stored in type of Uint64_t,  The most significant overflow result is lost in this Uint64_t type.

Is that right?