 ← CPL;
                    IF instruction has immediate operand
                         THEN (* Release parameters from called procedure’s stack *)
                              RSP ← RSP + SRC;
                    FI;
                    tempESP ← Pop();
                    tempSS ← Pop(); (* 64-bit pop; high-order 48 bits discarded; seg. desc. loaded *)
                    ESP ← tempESP;
                    SS ← tempSS;
         FI;
FI;
FOR each of segment register (ES, FS, GS, and DS)
   