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# add
Add two numbers with `avo`.
The [code generator](asm.go) is as follows:
[embedmd]:# (asm.go)
```go
// +build ignore
package main
import . "github.com/mmcloughlin/avo/build"
func main() {
TEXT("Add", NOSPLIT, "func(x, y uint64) uint64")
Doc("Add adds x and y.")
x := Load(Param("x"), GP64())
y := Load(Param("y"), GP64())
ADDQ(x, y)
Store(y, ReturnIndex(0))
RET()
Generate()
}
```
We use a [`go:generate`](https://blog.golang.org/generate) line to produce the assembly and Go stub files together.
[embedmd]:# (add_test.go go /.*go:generate.*/)
```go
//go:generate go run asm.go -out add.s -stubs stub.go
```
This produces [`add.s`](add.s) as follows:
[embedmd]:# (add.s)
```s
// Code generated by command: go run asm.go -out add.s -stubs stub.go. DO NOT EDIT.
#include "textflag.h"
// func Add(x uint64, y uint64) uint64
TEXT ·Add(SB), NOSPLIT, $0-24
MOVQ x+0(FP), AX
MOVQ y+8(FP), CX
ADDQ AX, CX
MOVQ CX, ret+16(FP)
RET
```
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