int fun(int a, int b) {
  char var[128] = "A";
   a = 0x4455;
   b = 0x6677;
   return a + b;
}
int main() {
    fun(0x8899,0x1100);
    return 0;
}

00401078   push        1100h //参数压栈，这里遵循__cdecl调用规范，参数由右向左
0040107D   push        8899h//压栈
00401082   call        @ILT+0(_fun) (00401005)
00401087   add         esp,8//被调用函数的堆栈由主调函数来清空

1:    int fun(int a, int b) {
0040B500   push        ebp // 
0040B501   mov         ebp,esp //调用函数通常的做法，通过ebp基址寄存器来操作堆//栈数据
0040B503   sub         esp,0C0h //为什么是C0h（不是因为堆栈保护，防止缓冲区overflow，而是
DEBUG选项造成的）
0040B509   push        ebx
0040B50A   push        esi
0040B50B   push        edi
0040B50C   lea         edi,[ebp-0C0h]
0040B512   mov         ecx,30h //C0h 除以4，就是30h，因为rep stos用的是dword 
0040B517   mov         eax,0CCCCCCCCh
0040B51C   rep stos    dword ptr [edi] //用0CCCCCCCCh初始化堆栈
2:       char var[128] = "A";
0040B51E   mov         ax,[string "A" (0041f10c)] //此时EBP = 0012FF24
0040B524   mov         word ptr [ebp-80h],ax //80h也就是128，写了一个字
0040B528   mov         ecx,1Fh //1Fh是31
0040B52D   xor         eax,eax //清零
0040B52F   lea         edi,[ebp-7Eh]
0040B532   rep stos    dword ptr [edi] //一共是32个双字，开始写了一个字，rep stos
0040B534   stos        word ptr [edi]//写入了31个双字，还剩下一个字由stos完成
//var的地址是：0x0012fea4
3:       a = 0x4455;
0040B536   mov         dword ptr [ebp+8],4455h
4:       b = 0x6677;
0040B53D   mov         dword ptr [ebp+0Ch],6677h
5:       return a + b;
0040B544   mov         eax,dword ptr [ebp+8]
0040B547   add         eax,dword ptr [ebp+0Ch] //返回值通过eax保存
6:    }
0040B54A   pop         edi
0040B54B   pop         esi
0040B54C   pop         ebx //弹栈
0040B54D   mov         esp,ebp
0040B54F   pop         ebp  //恢复ebp寄存器
0040B550   ret    //默认操作，恢复EIP：将堆栈中的00401087 pop给EIP