How to understand assmbly code ` 47ae26: 48 8d 0d bb 06 02 00
leaq 132795(%rip), %rcx # 0x49b4e8 <go:func.*+0x220>`
Go code:
```
//go:noinline
func add(a, b int) int {
defer func() {
fmt.Println(3)
}()
return a + b
}
func main() {
add(10, 20)
}
```
Build by `GOOS=linux GOARCH=amd64 GOSSAFUNC=main.add go21 build main.go`
Assembly code
```
objdump -D -S main | grep "main.add>:" -A 30
000000000047ae00 <main.add>:
; func add(a, b int) int {
47ae00: 49 3b 66 10 cmpq 16(%r14), %rsp
47ae04: 76 5b jbe 0x47ae61 <main.add+0x61>
47ae06: 55 pushq %rbp
47ae07: 48 89 e5 movq %rsp, %rbp
47ae0a: 48 83 ec 18 subq $24, %rsp
47ae0e: 66 44 0f d6 7c 24 10 movq %xmm15, 16(%rsp)
47ae15: c6 44 24 07 00 movb $0, 7(%rsp)
47ae1a: 48 c7 44 24 08 00 00 00 00 movq $0, 8(%rsp)
; return a + b
47ae23: 48 01 d8 addq %rbx, %rax
; defer func() {
47ae26: 48 8d 0d bb 06 02 00 leaq 132795(%rip), %rcx #
0x49b4e8 <go:func.*+0x220>
47ae2d: 48 89 4c 24 10 movq %rcx, 16(%rsp)
47ae32: c6 44 24 07 01 movb $1, 7(%rsp)
; return a + b
47ae37: 48 89 44 24 08 movq %rax, 8(%rsp)
47ae3c: c6 44 24 07 00 movb $0, 7(%rsp)
47ae41: e8 7a 00 00 00 callq 0x47aec0 <main.add.func1>
47ae46: 48 8b 44 24 08 movq 8(%rsp), %rax
47ae4b: 48 83 c4 18 addq $24, %rsp
47ae4f: 5d popq %rbp
47ae50: c3 retq
47ae51: e8 8a 47 fb ff callq 0x42f5e0
<runtime.deferreturn>
47ae56: 48 8b 44 24 08 movq 8(%rsp), %rax
47ae5b: 48 83 c4 18 addq $24, %rsp
47ae5f: 5d popq %rbp
47ae60: c3 retq
; func add(a, b int) int {
47ae61: 48 89 44 24 08 movq %rax, 8(%rsp)
```
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