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变量声明
5: func main() {
=> 6: var a int
7: a = 2
通过dlv的disass查看对应的汇编指令:
var.go:6 0x10cbacf 488d05aaae0000 lea rax, ptr [rip+0xaeaa] #lea 取地址，[rip+0xaeaa]对应的地址的值赋给rax([rip+0xaeaa]代表地址)
var.go:6 0x10cbad6 48890424 mov qword ptr [rsp], rax #把rax存储的值赋给[rsp]指向地址的值 *rsp = rax
var.go:6 0x10cbada e88122f4ff call $runtime.newobject #调用runtime.newobject函数，call <label>
var.go:6 0x10cbadf 488b442408 mov rax, qword ptr [rsp+0x8] # 调用newobject函数后的返回值存储在[rsp+0x8]，rax接收返回值(地址)
var.go:6 0x10cbae4 4889442478 mov qword ptr [rsp+0x78], rax # 使用局部变量[rsp+0x78]来接收newobject的返回值
var.go:6 0x10cbae9 48c70000000000 mov qword ptr [rax], 0x0 # a = 0 ,[rax]代表的不是地址，而是rax指向地址的值
var.go:7 0x10cbaf0 488b442478 mov rax, qword ptr [rsp+0x78] # 把[rsp+0x78]存储的内容加载到rax
var.go:7 0x10cbaf5 48c70002000000 mov qword ptr [rax], 0x2 # 把rax地址对应的值赋于2
通过dlv的si进行汇编级调试,首先使用regs查看寄存器的状态
var.go:6 0x10cbacf 488d05aaae0000 lea rax, ptr [rip+0xaeaa]
var.go:6 0x10cbad6 48890424 mov qword ptr [rsp], rax
代码执行后的变化
Rip = 0x00000000010cbacf => Rip = 0x00000000010cbad6 #代码地址移到下一行 0x10cbad6
Rsp = 0x000000c00009de88 => Rsp = 0x000000c00009de88 #
Rax = 0x000000c00009df08 => Rax = 0x00000000010d6980 #保存代码地址0x10d6980
Rbp = 0x000000c00009df78 => Rbp = 0x000000c00009df78
// rip = 0x00000000010cbacf [rip+0xaeaa]对应的地址为`0x10d6979`
(dlv) x -fmt hex -count 24 -size 1 0x10d6979
// lea rax, ptr [rip+0xaeaa]
(dlv) x -fmt hex -count 24 -size 1 0x000000c00009de88
0xc000065e88: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
//mov qword ptr [rsp], rax
(dlv) x -fmt hex -count 24 -size 1 0x000000c00009de88
0xc000065e88: 0x80 0x69 0x0d 0x01 0x00 0x00 0x00 0x00 //0x10d6980
(dlv) disass -a 0x10d6980 0x10d6988
.:0 0x10d6980 0800 or byte ptr [rax], al
.:0 0x10d6982 0000 add byte ptr [rax], al
.:0 0x10d6984 0000 add byte ptr [rax], al
.:0 0x10d6986 0000 add byte ptr [rax], al
执行语句:
var.go:6 0x10cbad6 48890424 mov qword ptr [rsp], rax
代码执行后的变化
Rip = 0x00000000010cbad6 => Rip = 0x00000000010cbada
Rsp = 0x000000c000065e88 => Rsp = 0x000000c000065e88
Rax = 0x00000000010d6980 => Rax = 0x00000000010d6980
Rbp = 0x000000c000065f78 => Rbp = 0x000000c000065f78
可以看到声明变量的时候，编译器调用了runtime.newobject，函数返回为内存地址。使用dlv查看函数跳转的地址
(dlv) print &runtime.newobject
(*)(0x100dd60)
(dlv) disass -a 0x100dd60 0x100dd66
TEXT runtime.newobject(SB) /usr/local/go/src/runtime/malloc.go
malloc.go:1176 0x100dd60 65 gs
malloc.go:1176 0x100dd61 48 rex.w
malloc.go:1176 0x100dd62 8b prefix(0x8b)
malloc.go:1176 0x100dd63 0c25 or al, 0x25
malloc.go:1176 0x100dd65 30 prefix(0x30)
# /usr/local/go/src/runtime/malloc.go:1176
// implementation of new builtin
// compiler (both frontend and SSA backend) knows the signature
// of this function
1176: func newobject(typ *_type) unsafe.Pointer {
1177: return mallocgc(typ.size, typ, true)
1178: }
执行语句:
var.go:6 0x10cbadf 488b442408 mov rax, qword ptr [rsp+0x8]
执行之后的值
Rip = 0x00000000010cbadf => Rip = 0x00000000010cbae4
Rsp = 0x000000c000065e88 => Rsp = 0x000000c000065e88
Rax = 0x000000c00009e000 => Rax = 0x000000c00009e000
Rbp = 0x000000c000065f78 => Rbp = 0x000000c000065f78
这种可以看出rsp的地址为0xc000065e88，[rsp+0x8]的值为0xc000065e90，查看[rsp+0x8]的内容是0xc00009e000
(dlv) x -fmt hex -count 24 -size 1 0x000000c000065e90
0xc000065e90: 0x00 0xe0 0x09 0x00 0xc0 0x00 0x00 0x00
0xc000065e98: 0x28 0x27 0x03 0x00 0xc0 0x00 0x00 0x00
0xc000065ea0: 0xf5 0xd7 0x00 0x01 0x00 0x00 0x00 0x00
mov rax, qword ptr [rsp+0x8]的含义就是把[rsp+0x8]地址存储的内容赋给rax
以下执行的代码解释
var.go:7 0x10cbaf0 488b442478 mov rax, qword ptr [rsp+0x78]
var.go:7 0x10cbaf5 48c70002000000 mov qword ptr [rax], 0x2
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=> 9: b := new(int)
10: b = &a
11: *b = 5
汇编指令:
=> var.go:9 0x10cbafc 488d057dae0000 lea rax, ptr [rip+0xae7d]
var.go:9 0x10cbb03 48890424 mov qword ptr [rsp], rax
var.go:9 0x10cbb07 e85422f4ff call $runtime.newobject #创建对象
var.go:9 0x10cbb0c 488b442408 mov rax, qword ptr [rsp+0x8] #接收返回值[rsp+0x8]，放在rax中
var.go:9 0x10cbb11 4889442448 mov qword ptr [rsp+0x48], rax #再把返回值放在本地变量[rsp+0x48]中
var.go:10 0x10cbb16 488b442478 mov rax, qword ptr [rsp+0x78] #首先是取[rsp+0x78]地址的内容
var.go:10 0x10cbb1b 4889442448 mov qword ptr [rsp+0x48], rax # b = &a
var.go:11 0x10cbb20 8400 test byte ptr [rax], al #
var.go:11 0x10cbb22 48c70005000000 mov qword ptr [rax], 0x5 # *b = 5
执行语句:
=> 13: s := make([]int, 6)
14: s[0] = 2
创建数组调用func makeslice(et *_type, len, cap int) unsafe.Pointer，需要传入参数len和cap,返回一个地址指针int
=> var.go:13 0x10cbb29 488d0550ae0000 lea rax, ptr [rip+0xae50]
var.go:13 0x10cbb30 48890424 mov qword ptr [rsp], rax
var.go:13 0x10cbb34 48c744240806000000 mov qword ptr [rsp+0x8], 0x6 # len长度参数
var.go:13 0x10cbb3d 48c744241006000000 mov qword ptr [rsp+0x10], 0x6 # cap容量参数
var.go:13 0x10cbb46 e85550f8ff call $runtime.makeslice
var.go:13 0x10cbb4b 488b442418 mov rax, qword ptr [rsp+0x18] # 返回值unsafe.Pointer
var.go:13 0x10cbb50 4889842480000000 mov qword ptr [rsp+0x80], rax #使用[rsp+0x80]接收返回值
var.go:13 0x10cbb58 48c784248800000006000000 mov qword ptr [rsp+0x88], 0x6 #使用[rsp+0x88]存储len
var.go:13 0x10cbb64 48c784249000000006000000 mov qword ptr [rsp+0x90], 0x6 #使用[rsp+0x90]存储cap
var.go:14 0x10cbb70 eb00 jmp 0x10cbb72
var.go:14 0x10cbb72 48c70002000000 mov qword ptr [rax], 0x2 # s[0] = 2
使用dlv查看数组的值
(dlv) print &s
(*[]int)(0xc000111f08)
(dlv) x -fmt hex -count 24 -size 1 0xc000111f08
0xc000111f08: 0x30 0x60 0x12 0x00 0xc0 0x00 0x00 0x00 # 数组的地址arr = 0xc000126030
0xc000111f10: 0x06 0x00 0x00 0x00 0x00 0x00 0x00 0x00 # len = 0x06
0xc000111f18: 0x06 0x00 0x00 0x00 0x00 0x00 0x00 0x00 # cap = 0x06
(dlv) x -fmt hex -count 24 -size 1 0xc000126030
0xc000126030: 0x02 0x00 0x00 0x00 0x00 0x00 0x00 0x00 # 数组的首个元素 0x02
0xc000126038: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0xc000126040: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
执行语句:
=> 16: c := make(chan int, 5)
17: c <- 3
调用的函数func makechan(t *chantype, size int) *hchan
=> var.go:16 0x10cbb79 488d0500a80000 lea rax, ptr [rip+0xa800]
var.go:16 0x10cbb80 48890424 mov qword ptr [rsp], rax
var.go:16 0x10cbb84 48c744240805000000 mov qword ptr [rsp+0x8], 0x5 # size 5
var.go:16 0x10cbb8d e80e90f3ff call $runtime.makechan
var.go:16 0x10cbb92 488b442410 mov rax, qword ptr [rsp+0x10] # 返回值*hchan
var.go:16 0x10cbb97 4889442440 mov qword ptr [rsp+0x40], rax # 使用[rsp+0x40]保存makechan函数返回值
var.go:17 0x10cbb9c 48890424 mov qword ptr [rsp], rax # func chansend1(c *hchan, elem unsafe.Pointer) 第一个参数*hchan
var.go:17 0x10cbba0 488d05011b0300 lea rax, ptr [rip+0x31b01] # 0x00000000010fd6a8 代表的是3
var.go:17 0x10cbba7 4889442408 mov qword ptr [rsp+0x8], rax
var.go:17 0x10cbbac e82f93f3ff call $runtime.chansend1 # 开始发送数据
[rip+0x31b01]代表常量3
(dlv) x -fmt hex -count 24 -size 1 0x00000000010fd6a8
0x10fd6a8: 0x03 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x10fd6b0: 0x16 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x10fd6b8: 0x15 0x00 0x00 0x00 0x00 0x00 0x00 0x00
执行语句:
=> 31: man := Man{}
32: var manImpl IMan
33: manImpl = &man
代码对应的汇编语句:
=> var.go:31 0x10cbc45* 488d05f4160100 ea rax, ptr [rip+0x116f4] #指向*_type参数
var.go:31 0x10cbc4c 48890424 mov qword ptr [rsp], rax #
var.go:31 0x10cbc50 e80b21f4ff call $runtime.newobject
var.go:31 0x10cbc55 488b7c2408 mov rdi, qword ptr [rsp+0x8] #newobject返回值
var.go:31 0x10cbc5a 4889bc2488000000 mov qword ptr [rsp+0x88], rdi #使用[rsp+0x88]接收返回值
var.go:31 0x10cbc62 48c7470800000000 mov qword ptr [rdi+0x8], 0x0 #置零
var.go:31 0x10cbc6a 833d7f670d0000 cmp dword ptr [runtime.writeBarrier], 0x0
var.go:31 0x10cbc71 7405 jz 0x10cbc78
var.go:31 0x10cbc73 e9bc020000 jmp 0x10cbf34
var.go:31 0x10cbc78 48c70700000000 mov qword ptr [rdi], 0x0
var.go:31 0x10cbc7f 90 nop
var.go:31 0x10cbc80 eb00 jmp 0x10cbc82
var.go:32 0x10cbc82 0f57c0 xorps xmm0, xmm0
var.go:32 0x10cbc85 0f11842498000000 movups xmmword ptr [rsp+0x98], xmm0 #本地变量[rsp+0x98]
var.go:33 0x10cbc8d 488b842488000000 mov rax, qword ptr [rsp+0x88] #man的地址赋给rax
var.go:33 0x10cbc95 4889442458 mov qword ptr [rsp+0x58], rax #
var.go:33 0x10cbc9a 488d0d17370300 lea rcx, ptr [rip+0x33717]
var.go:33 0x10cbca1 48898c2498000000 mov qword ptr [rsp+0x98], rcx
var.go:33 0x10cbca9 48898424a0000000 mov qword ptr [rsp+0xa0], rax #接口指针.data = &man
函数调用
5: func main() {
=> 6: b := 8
7: c := callMe(b)
8: fmt.Println(c)
9: }
10:
11: func callMe(a int) int {
12: return a + 5
13:}
// 打印函数地址
(dlv) print &main.callMe
(*)(0x10cbba0)
// 调用函数对应的汇编指令:
=> func.go:6 0x10cbac1 48c744243808000000 mov qword ptr [rsp+0x38], 0x8
func.go:7 0x10cbaca 48c7042408000000 mov qword ptr [rsp], 0x8 #rsp作为第一个参数8
func.go:7 0x10cbad2 e8c9000000 call $main.callMe
func.go:7 0x10cbad7 488b442408 mov rax, qword ptr [rsp+0x8] #rax接收返回值
func.go:7 0x10cbadc 4889442430 mov qword ptr [rsp+0x30], rax #本地变量c就是[rsp+0x30]接收返回值
// 查看main.callMe的函数对应的汇编指令:
(dlv) disass -a 0x10cbba0 0x10cbbc0
TEXT main.callMe(SB) /Users/ymm/work/mygithub/go-build/code/go/assembly/func/func.go
func.go:11 0x10cbba0 48c744241000000000 mov qword ptr [rsp+0x10], 0x0 # 返回值
func.go:12 0x10cbba9 488b442408 mov rax, qword ptr [rsp+0x8] # 第一个参数
func.go:12 0x10cbbae 4883c005 add rax, 0x5
.:0 0x10cbbb2 4889442410 mov qword ptr [rsp+0x10], rax # 把结果放到返回值中
.:0 0x10cbbb7 c3 ret # 返回
.:0 0x10cbbb8 0000 add byte ptr [rax], al
.:0 0x10cbbba 0000 add byte ptr [rax], al
.:0 0x10cbbbc 0000 add byte ptr [rax], al
.:0 0x10cbbbe 0000 add byte ptr [rax], al
👉 c/c++常用语句对应的汇编指令
对象调用方法的实现
go对象调用方法实现
package main
import "fmt"
type Man struct {
Name string
Age int
}
func (man *Man) walk() string {
return man.Name
}
func main() {
man := Man{Name: "xiaoming", Age: 18}
man.walk()
}
go语言中
string的数据结构为StringHeader,包含数据部分和len两部分。
type StringHeader struct {
Data uintptr
Len int
}
使用dlv调试ls查看代码
15: func main() {
16: man := Man{Name: "xiaoming", Age: 18}
=> 17: man.walk()
18: }
对应的汇编代码
(dlv) disass
TEXT main.main(SB) /Users/ymm/work/mygithub/go-build/code/go/assembly/object/object.go
object.go:15 0x10cbc80 65488b0c2530000000 mov rcx, qword ptr gs:[0x30]
object.go:15 0x10cbc89 483b6110 cmp rsp, qword ptr [rcx+0x10]
object.go:15 0x10cbc8d 7655 jbe 0x10cbce4
object.go:15 0x10cbc8f 4883ec38 sub rsp, 0x38
object.go:15 0x10cbc93 48896c2430 mov qword ptr [rsp+0x30], rbp
object.go:15 0x10cbc98 488d6c2430 lea rbp, ptr [rsp+0x30]
object.go:16 0x10cbc9d 48c744241800000000 mov qword ptr [rsp+0x18], 0x0 #把[rsp+0x18]内容置零
object.go:16 0x10cbca6 0f57c0 xorps xmm0, xmm0
object.go:16 0x10cbca9 0f11442420 movups xmmword ptr [rsp+0x20], xmm0
object.go:16 0x10cbcae 488d0517560200 lea rax, ptr [rip+0x25617] #加载字符串的地址
object.go:16 0x10cbcb5 4889442418 mov qword ptr [rsp+0x18], rax #把字符串的地址赋给Name string部分
object.go:16 0x10cbcba 48c744242008000000 mov qword ptr [rsp+0x20], 0x8 #把字符串的长度赋给string len部分
object.go:16 0x10cbcc3 48c744242812000000 mov qword ptr [rsp+0x28], 0x12 #把age赋给结构体man.age福分
=> object.go:17 0x10cbccc* 488d442418 lea rax, ptr [rsp+0x18] #把man变量地址加载到rax
object.go:17 0x10cbcd1 48890424 mov qword ptr [rsp], rax #把man变量地址加载到rsp，作为第一个参数
object.go:17 0x10cbcd5 e8c6fdffff call $main.(*Man).walk #调用方法walk
object.go:18 0x10cbcda 488b6c2430 mov rbp, qword ptr [rsp+0x30]
object.go:18 0x10cbcdf 4883c438 add rsp, 0x38
object.go:18 0x10cbce3 c3 ret
object.go:15 0x10cbce4 e83712faff call $runtime.morestack_noctxt
.:0 0x10cbce9 eb95 jmp $main.main
查看字符串的内存
// xiaoming 78 69 61 6f 6d 69 6e 67
(dlv) x -fmt hex -count 32 -size 1 0x10f12cc
0x10f12cc: 0x78 0x69 0x61 0x6f 0x6d 0x69 0x6e 0x67
0x10f12d4: 0x20 0x28 0x66 0x6f 0x72 0x63 0x65 0x64
0x10f12dc: 0x29 0x20 0x2d 0x3e 0x20 0x6e 0x6f 0x64
0x10f12e4: 0x65 0x3d 0x20 0x62 0x6c 0x6f 0x63 0x6b
查看walk方法
=> 8: func (man *Man) walk() string {
9: return man.Name
10: }
对应的汇编指令
(dlv) disass
TEXT main.(*Man).walk(SB) /Users/ymm/work/mygithub/go-build/code/go/assembly/object/object.go
=> object.go:8 0x1067bc0 0f57c0 xorps xmm0, xmm0
object.go:8 0x1067bc3 0f11442410 movups xmmword ptr [rsp+0x10], xmm0 # 初始化返回值
object.go:9 0x1067bc8 488b442408 mov rax, qword ptr [rsp+0x8] #[rsp+0x8]就是传进来的man变量地址
object.go:9 0x1067bcd 8400 test byte ptr [rax], al #
.:0 0x1067bcf 488b08 mov rcx, qword ptr [rax] #获取man结构体中的string数据
.:0 0x1067bd2 488b4008 mov rax, qword ptr [rax+0x8] #获取man结构体中的string长度
.:0 0x1067bd6 48894c2410 mov qword ptr [rsp+0x10], rcx #返回值string的数据部分
.:0 0x1067bdb 4889442418 mov qword ptr [rsp+0x18], rax #返回值string的len部分
.:0 0x1067be0 c3 ret
从汇编语言可以看出man.walk()是把man变量作为方法walk参数使用，这样就可以使用结构体man的成员变量。相当于c++中的this
c++对象调用方法实现
#include <iostream>
class Man
{
public:
char *name;
int age;
public:
char *walk();
};
char *Man::walk()
{
return this->name;
}
int main()
{
Man man;
man.name = "xiaoming";
man.age = 19;
char *name = man.walk();
std::cout << "Hello World " << name << std::endl;
}
编译参数为g++ -g -o test test.cpp,使用gdb对test文件进行调试
-exec disass /m
Dump of assembler code for function main():
19 {
0x00000000004007ef <+0>: push rbp
0x00000000004007f0 <+1>: mov rbp,rsp
0x00000000004007f3 <+4>: sub rsp,0x20
20 Man man;
21 man.name = "xiaoming";
0x00000000004007f7 <+8>: mov QWORD PTR [rbp-0x20],0x400930 #man变量地址为[rbp-0x20], 也是name的地址 8个字节
22 man.age = 19;
0x00000000004007ff <+16>: mov DWORD PTR [rbp-0x18],0x13 #[rbp-0x18]为man.age成员变量的地址
23 char *name = man.walk();
=> 0x0000000000400806 <+23>: lea rax,[rbp-0x20] #[rbp-0x20]为变量man的地址，加载到rax寄存器
0x000000000040080a <+27>: mov rdi,rax #把man对象的地址加载到rdi
0x000000000040080d <+30>: call 0x4007de <Man::walk()> #调用方法0x4007de，也就是 <Man::walk()>
0x0000000000400812 <+35>: mov QWORD PTR [rbp-0x8],rax #walk函数的返回值放到rax中，存储到本地变量[rbp-0x8]中
24
25 std::cout << "Hello World " << name << std::endl;
0x0000000000400816 <+39>: mov esi,0x400939
0x000000000040081b <+44>: mov edi,0x601060
0x0000000000400820 <+49>: call 0x4006c0 <_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc@plt>
0x0000000000400825 <+54>: mov rdx,QWORD PTR [rbp-0x8]
0x0000000000400829 <+58>: mov rsi,rdx
0x000000000040082c <+61>: mov rdi,rax
0x000000000040082f <+64>: call 0x4006c0 <_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc@plt>
0x0000000000400834 <+69>: mov esi,0x4006e0
0x0000000000400839 <+74>: mov rdi,rax
0x000000000040083c <+77>: call 0x4006d0 <_ZNSolsEPFRSoS_E@plt>
26 } 0x0000000000400841 <+82>: mov eax,0x0
0x0000000000400846 <+87>: leave
0x0000000000400847 <+88>: ret
End of assembler dump.
man.walk()方法的汇编实现
Dump of assembler code for function Man::walk():
14 {
0x00000000004007de <+0>: push rbp
0x00000000004007df <+1>: mov rbp,rsp
0x00000000004007e2 <+4>: mov QWORD PTR [rbp-0x8],rdi #跳转到walk方法是,rdi为对象man的内存地址
15 return this->name;
=> 0x00000000004007e6 <+8>: mov rax,QWORD PTR [rbp-0x8] #[rbp-0x8]的地址页尾man.name的地址
0x00000000004007ea <+12>: mov rax,QWORD PTR [rax] #rax为返回值
16 }
0x00000000004007ed <+15>: pop rbp
0x00000000004007ee <+16>: ret
可以看出golang与c++调用方法的汇编实现是一致的，首先把对象作为参数传入方法，然后再去使用对象。
goroutine的汇编实现
package main
import "time"
func main() {
a := 5
go func() {
a = 6
}()
time.Sleep(time.Second)
}
查看汇编实现
5: func main() {
6: a := 5
7: go func() {
8: a = 6
=> 9: }()
10:
11: time.Sleep(time.Second)
12: }
(dlv) disass -a 0x106ea00 0x106ea8c
TEXT main.main(SB) /Users/ymm/work/mygithub/go-build/code/go/assembly/goroutine/goroutine.go
goroutine.go:6 0x106ea00 5c pop rsp
goroutine.go:6 0x106ea01 7600 jbe 0x106ea03
goroutine.go:6 0x106ea03 004889 add byte ptr [rax-0x77], cl
goroutine.go:6 0x106ea06 0424 add al, 0x24
goroutine.go:6 0x106ea08 e893e0f9ff call $runtime.newobject
goroutine.go:6 0x106ea0d 488b442408 mov rax, qword ptr [rsp+0x8]
goroutine.go:6 0x106ea12 4889442420 mov qword ptr [rsp+0x20], rax
goroutine.go:6 0x106ea17 48c70005000000 mov qword ptr [rax], 0x5 # a := 5
goroutine.go:7 0x106ea1e 488b442420 mov rax, qword ptr [rsp+0x20] # 把a变量地址加载到rax
goroutine.go:9 0x106ea23 4889442418 mov qword ptr [rsp+0x18], rax # 把a变量地址加载到[rsp+0x18]
goroutine.go:7 0x106ea28 c7042408000000 mov dword ptr [rsp], 0x8 # 把8加载到rsp，作为第一个参数
goroutine.go:7 0x106ea2f 488d0ddac80100 lea rcx, ptr [rip+0x1c8da] # [rip+0x1c8da]对应匿名函数地址
goroutine.go:7 0x106ea36 48894c2408 mov qword ptr [rsp+0x8], rcx # 第二个参数为匿名函数地址 [rsp+0x8] = [rip+0x1c8da]
goroutine.go:7 0x106ea3b 4889442410 mov qword ptr [rsp+0x10], rax # 第三个值为a变量的地址
goroutine.go:7 0x106ea40 e85b01fdff call $runtime.newproc # 调用newproc函数，参数为[rsp]和[rsp+0x8]
goroutine.go:11 0x106ea45 48c7042400ca9a3b mov qword ptr [rsp], 0x3b9aca00
goroutine.go:11 0x106ea4d e8ce49ffff call $time.Sleep
goroutine.go:12 0x106ea52 488b6c2428 mov rbp, qword ptr [rsp+0x28]
goroutine.go:12 0x106ea57 4883c430 add rsp, 0x30
goroutine.go:12 0x106ea5b c3 ret
goroutine.go:5 0x106ea5c 0f1f4000 nop dword ptr [rax], eax
goroutine.go:5 0x106ea60 e8bb5cffff call $runtime.morestack_noctxt
.:0 0x106ea65 e976ffffff jmp $main.main
.:0 0x106ea6a cc int3
go func调用的是匿名函数
// lea rcx, ptr [rip+0x1c8da] 执行后的结果
Rcx = 0x000000000108b310
// 查看rcx对应的内存值
(dlv) x -fmt hex -count 32 -size 1 0x000000000108b310
0x108b310: 0x80 0xea 0x06 0x01 0x00 0x00 0x00 0x00
0x108b318: 0xe0 0xf7 0x05 0x01 0x00 0x00 0x00 0x00
0x108b320: 0x00 0x0c 0x06 0x01 0x00 0x00 0x00 0x00
0x108b328: 0x20 0xfa 0x03 0x01 0x00 0x00 0x00 0x00
// 匿名函数地址为`0x106ea80`,查看函数实现， 对应goroutine.go:8也就是 a = 6
(dlv) disass -a 0x106ea80 0x106ea88
TEXT main.main.func1(SB) /Users/ymm/work/mygithub/go-build/code/go/assembly/goroutine/goroutine.go
goroutine.go:8 0x106ea80 488b442408 mov rax, qword ptr [rsp+0x8]
goroutine.go:8 0x106ea85 48 rex.w
goroutine.go:8 0x106ea86 c7 prefix(0xc7)
goroutine.go:8 0x106ea87 00 <no instruction>
call $runtime.newproc函数实现如下，最终还是由协程调用匿名函数fn *funcval
// siz 参数个数， fn是协程调用的函数
func newproc(siz int32, fn *funcval) {
argp := add(unsafe.Pointer(&fn), sys.PtrSize)
gp := getg()
pc := getcallerpc()
systemstack(func() {
newg := newproc1(fn, argp, siz, gp, pc)
_p_ := getg().m.p.ptr()
runqput(_p_, newg, true)
if mainStarted {
wakep()
}
})
}
//对应的函数
type funcval struct {
fn uintptr
// variable-size, fn-specific data here
}
