> For the complete documentation index, see [llms.txt](https://zenofchain.gitbook.io/sway-bian-cheng-yu-yan-geng-xin-zhong-the-sway-programming-languageupdatin/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zenofchain.gitbook.io/sway-bian-cheng-yu-yan-geng-xin-zhong-the-sway-programming-languageupdatin/6.-gao-ji-gai-nian-advanced-concepts/6.4-ji-assembly.md).

# 6.4 集 (Assembly)

While many users will never have to touch assembly language while writing sway code, it is a powerful tool that enables many advanced use-cases (ie: optimizations, building libraries, etc).

虽然许多用户在编写 sway 代码时永远不必接触汇编语言，但它是一个支持许多高级用例（即：优化、构建库等）的强大工具。

### ASM块 (ASM Block)

In Sway, the way we use assembly inline is to declare an asm block like this:

在 Sway 中，我们使用内联汇编的方式是像这样声明一个 asm 块：

```
asm() {...}

```

Declaring an `asm` block is similar to declaring a function. We can specify register names to operate on as arguments, we can perform operations within the block, and we can return a value. Here's an example showing what this might look like:

声明一个 `asm` 块类似于声明一个函数。我们可以指定要操作的注册器名称作为参数，我们可以在块内执行操作，我们可以返回一个值。这是一个示例，显示了其外观：

```
pub fn add_1(num: u32) -> u32 {
    asm(r1: num, r2) {
        add r2 r1 one;
        r2: u32
    }
}

```

An `asm` block can only return a single register. If you really need to return more than one value, you can modify a tuple. Here's an example showing how can implement this `(u64, u64)`:

一个 `asm` 块只能返回一个注册器。如果你真的需要返回多个值，你可以修改一个元组。下面是一个示例，展示了如何实现这个`(u64, u64)`：

```
script;

fn adder(a: u64, b: u64, c: u64) -> (u64, u64) {
    let empty_tuple = (0u64, 0u64);
    asm(output: empty_tuple, r1: a, r2: b, r3: c, r4, r5) {
        add  r4 r1 r2; // add a & b and put the result in r4
        add  r5 r2 r3; // add b & c and put the result in r5
        sw   output r4 i0; // store the word in r4 in output + 0 words
        sw   output r5 i1; // store the word in r5 in output + 1 word
        output: (u64, u64) // return both values
    }
}

fn main() -> bool {
    let (first, second) = adder(1, 2, 3);
    assert(first == 3);
    assert(second == 5);
    true
}

```

Note that this is contrived example meant to demonstrate the syntax; there's absolutely no need to use assembly to add integers!

请注意，这是人为设计的示例，旨在演示语法；绝对不需要使用汇编来添加整数！

Note that in the above example:

请注意，在上面的示例中：

* we initialized the register `r1` with the value of `num`.\
  我们用 `num` 的值初始化了注册器 `r1`
* we declared a second register `r2` (you may choose any register names you want).\
  我们声明了第二个注册器 `r2`（您可以选择任何您想要的注册器名称）
* we use the `add` opcode to add `one` to the value of `r1` and store it in `r2`.\
  我们使用 `add` 操作码将 `one` 添加到 `r1` 的值并将其存储在 `r2` 中
* `one` is an example of a "reserved register", of which there are 16 in total. Further reading on this is linked below under "Semantics".\
  `one` 是“保留注册器”的示例，总共有 16 个。关于此的进一步阅读链接在下面的“语义”下
* we return `r2` & specify the return type as being u32 (the return type is u64 by default).\
  我们返回 `r2` 并将返回类型指定为 u32（返回类型默认为 u64）。

An important note is that the `ji` and `jnei` opcodes are not available within an `asm` block. For those looking to introduce control flow to `asm` blocks, it is recommended to surround smaller chunks of `asm` with control flow (`if`, `else`, and `while`).

需要注意的是，`ji` 和 `jnei` 操作码在 `asm` 块中不可用。对于那些希望将控制流引入 `asm` 块的人，建议用控制流（`if`、`else` 和 `while`）包围较小的 `asm` 块。

### 有用的网址 (Helpful Links)

For examples of assembly in action, check out the [Sway standard library](https://github.com/FuelLabs/sway/tree/master/sway-lib-std).\
有关运行中的程序集示例，请查看 [Sway 标准库](https://github.com/FuelLabs/sway/tree/master/sway-lib-std)。

For a complete list of all instructions supported in the FuelVM: [Instructions](https://fuellabs.github.io/fuel-specs/master/vm/instruction_set).\
如需 FuelVM 支持的所有指令的完整列表：[说明](https://fuellabs.github.io/fuel-specs/master/vm/instruction_set)。

And to learn more about the FuelVM semantics: [Semantics](https://fuellabs.github.io/fuel-specs/master/vm#semantics).\
并了解有关 FuelVM 语义的更多信息：[语义](https://fuellabs.github.io/fuel-specs/master/vm#semantics)。