 not within stack limits
                         THEN #SS(0); FI;
         FI;
    IF return code segment selector is NULL
         THEN #GP(0); FI;
    IF return code segment selector addresses descriptor beyond descriptor table limit
         THEN #GP(selector); FI;
    Obtain descriptor to which return code segment selector points from descriptor table;
    IF return code segment descriptor is not a code segment
         THEN #GP(selector); FI;
    IF return code segment selector RPL &lt; CPL
         T