0x00000000: 33c0          : xor eax, eax

00110011 11 000 000                                                                                                                                             

00110011|                                      opcode `xor`

00110011|                                      operand code `Gv_Ev`

        |11                                    mmm field is a register number (mod bits: 11)

        |       000                            `eax` (`mmm` selects register number 0)

        |   000                                `eax` (`rrr` selects register number 0)

        |

        opcode ends/operands begin (typically)

0x00000002: e878563412    : call $+0x12345678

11101000 01111000010101100011010000010010                                                                                                                       

11101000|                                                              opcode `call`

11101000|                                                              operand code `Jvds`

        |01111000010101100011010000010010                              4-byte immediate: 0x12345678

        |

        opcode ends/operands begin (typically)

0x00000007: c3            : ret

11000011                                                                                                                                                        

11000011|                              opcode `ret`

11000011|                              operand code `Nothing`

        |

        opcode ends/operands begin (typically)