lect4(SRC2[383:256], imm8[7:6]);
    TMP_DEST[415:384]←Select4(SRC1[511:384], imm8[1:0]);
    TMP_DEST[447:416]←Select4(SRC1[511:384], imm8[3:2]);
    TMP_DEST[479:448]←Select4(SRC2[511:384], imm8[5:4]);
    TMP_DEST[511:480]←Select4(SRC2[511:384], imm8[7:6]);
FI;
FOR j←0 TO KL-1
    i←j * 32
    IF k1[j] OR *no writemask*
        THEN DEST[i+31:i]←TMP_DEST[i+31:i]
        ELSE
            IF *merging-masking*
                        ; merging-masking
                THEN *DEST[i+31:i] remains