REX.W + 0F A5    SHLD r/m64, r64, CL     B  Valid    N.E.    Shift r/m64 to left CL places while shifting bits from r64 in from the right.
    REX.W + 0F AD    SHRD r/m64, r64, CL     B  Valid    N.E.    Shift r/m64 to right CL places while shifting bits from r64 in from the left.