x86 / AMD64 assembly instructions are two major styles Intel assembler and AT & T assembler, are in the Microsoft Windows / Visual C ++ with the GNU / Gas uses (Gas can also use the Intel assembly style):
| project | Intel style | AT & T style |
|---|---|---|
| Operation sequence number | Preceding destination operand | Source operand front |
| register | AS | Plus a prefix% |
| Immediate | AS | Plus $ prefix |
| Hexadecimal number immediately | With the suffix B and H respectively represent binary hexadecimal to hexadecimal letter prefix to the beginning of the 0 | 0x prefix |
| Access memory length representation | Prefix BYTE PTR, WORD PTR, DWORD PTR and QWORD PTR represents byte, word, doubleword, quadword, and | Suffix b, w, l, q represents a byte, word, doubleword, quadword, and |
| Reference value of a global or static variable var | [where] | where |
| Reference address global or static variable var | where | $ each |
| Refers to a local variable | Based on need stack pointer (RSP) | |
| Absolute addressing | [imm] | imm |
| Indirect addressing | [reg] | (%reg) |
| Base address relative addressing | [reg +imm] | imm(%reg) |
| Indexed addressing | [base+index] | (base,index) |
| Indexed addressing | imm[base+index] | imm(base,index) |
| The proportion of indexed addressing | imm[base + index * scale ] | imm(base, index, scale) |
| 1,2,4,8 scale which is only a number (1 is an ordinary write omitted Indexed) | ||
| Code comments | Single-line comments with; + annotation content. For example: mov rax, rdx; this is a comment | |
| note | Here imm is immediate, base and index registers as, scale telescopic amount |