fun F8(i0, var Q : ushort queue) {
    val ii = i0?ext(32)&(~1) | (i0?bit(0)?ext(32)<<5);
    Q?push_back(ii?cvt(ushort) + 256?cvt(ushort));
    Q?push_back(ii?cvt(ushort) + 257?cvt(ushort));
    val xx = fregs[ii]?ext(64) << 32;
    return (xx | fregs[ii+1]?ext(64))?cast(double);
}