fun F8(i0, vv) {
    val ii = i0?ext(32)&(~1) | (i0?bit(0)?ext(32)<<5);
    destQ?push_back(ii?cvt(ushort) + 256?cvt(ushort));
    destQ?push_back(ii?cvt(ushort) + 257?cvt(ushort));
    fregs[ii] = vv?cast(unsigned[64])?bits(32,63);
    fregs[ii+1] = vv?cast(unsigned[64])?bits(32);
}