user: 这段汇编代码用C语言表示是什么样的：

```asm
<serial_open>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x50,%rsp
  mov    %rdi,-0x48(%rbp)
  mov    %esi,-0x4c(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x8(%rbp)
  xor    %eax,%eax
  mov    D38(%rip),%rax
  mov    (%rax),%edx
  mov    D156(%rip),%rax
  mov    (%rax),%eax
  or     %eax,%edx
  mov    D109(%rip),%rax
  mov    (%rax),%eax
  or     %eax,%edx
  mov    -0x48(%rbp),%rax
  mov    %edx,%esi
  mov    %rax,%rdi
  call   <open@plt>
  mov    %eax,-0x34(%rbp)
  cmpl   $0x0,-0x34(%rbp)
  jle    L75
  lea    -0x30(%rbp),%rax
  mov    $0x20,%edx
  mov    $0x0,%esi
  mov    %rax,%rdi
  call   <memset@plt>
  lea    -0x30(%rbp),%rdx
  mov    -0x34(%rbp),%eax
  mov    %rdx,%rsi
  mov    %eax,%edi
  call   <tcgetattr@plt>
  test   %rax,%rax
  je     L85
  mov    $0xffffffff,%eax
  jmp    L81
L85:
  mov    -0x4c(%rbp),%edx
  lea    -0x30(%rbp),%rax
  mov    %edx,%esi
  mov    %rax,%rdi
  call   <cfsetospeed@plt>
  test   %rax,%rax
  je     L12
  mov    $0xffffffff,%eax
  jmp    L81
L12:
  mov    -0x4c(%rbp),%edx
  lea    -0x30(%rbp),%rax
  mov    %edx,%esi
  mov    %rax,%rdi
  call   <cfsetispeed@plt>
  test   %rax,%rax
  je     L22
  mov    $0xffffffff,%eax
  jmp    L81
L22:
  mov    -0x30(%rbp),%edx
  mov    D97(%rip),%rax
  mov    (%rax),%eax
  not    %eax
  and    %eax,%edx
  mov    D160(%rip),%rax
  mov    (%rax),%eax
  or     %edx,%eax
  mov    %eax,-0x30(%rbp)
  mov    -0x2c(%rbp),%edx
  mov    D138(%rip),%rax
  mov    (%rax),%eax
  not    %eax
  and    %edx,%eax
  mov    %eax,-0x2c(%rbp)
  mov    -0x2c(%rbp),%edx
  mov    D131(%rip),%rax
  mov    (%rax),%eax
  not    %eax
  and    %edx,%eax
  mov    %eax,-0x2c(%rbp)
  mov    -0x2c(%rbp),%edx
  mov    D70(%rip),%rax
  mov    (%rax),%eax
  not    %eax
  and    %edx,%eax
  mov    %eax,-0x2c(%rbp)
  movq   $0x0,-0x18(%rbp)
  movq   $0x0,-0x20(%rbp)
  mov    -0x28(%rbp),%rdx
  mov    D2(%rip),%rax
  mov    (%rax),%rax
  shl    $0x2,%rax
  add    %rdx,%rax
  movl   $0x1,(%rax)
  mov    -0x28(%rbp),%rdx
  mov    D15(%rip),%rax
  mov    (%rax),%rax
  shl    $0x2,%rax
  add    %rdx,%rax
  movl   $0x5,(%rax)
  mov    -0x2c(%rbp),%edx
  mov    D35(%rip),%rax
  mov    (%rax),%ecx
  mov    D24(%rip),%rax
  mov    (%rax),%eax
  or     %eax,%ecx
  mov    D77(%rip),%rax
  mov    (%rax),%eax
  or     %ecx,%eax
  not    %eax
  and    %edx,%eax
  mov    %eax,-0x2c(%rbp)
  mov    -0x30(%rbp),%edx
  mov    D36(%rip),%rax
  mov    (%rax),%ecx
  mov    D7(%rip),%rax
  mov    (%rax),%eax
  or     %ecx,%eax
  or     %edx,%eax
  mov    %eax,-0x30(%rbp)
  mov    -0x30(%rbp),%edx
  mov    D62(%rip),%rax
  mov    (%rax),%ecx
  mov    D114(%rip),%rax
  mov    (%rax),%eax
  or     %ecx,%eax
  not    %eax
  and    %edx,%eax
  mov    %eax,-0x30(%rbp)
  mov    -0x30(%rbp),%edx
  mov    D85(%rip),%rax
  mov    (%rax),%eax
  not    %eax
  and    %edx,%eax
  mov    %eax,-0x30(%rbp)
  mov    D12(%rip),%rax
  mov    (%rax),%ecx
  lea    -0x30(%rbp),%rdx
  mov    -0x34(%rbp),%eax
  mov    %ecx,%esi
  mov    %eax,%edi
  call   <tcsetattr@plt>
  test   %rax,%rax
  je     L75
  mov    $0xffffffff,%eax
  jmp    L81
L75:
  mov    -0x34(%rbp),%eax
L81:
  mov    -0x8(%rbp),%rdx
  sub    %fs:0x28,%rdx
  je     L54
  call   <__stack_chk_fail@plt>
L54:
  leave
  ret
```

assistant: ```c
int serial_open(const char *device, speed_t speed) {
  int fd = open(device, O_RDWR | O_NOCTTY | O_SYNC);
  if (fd > 0) {
    struct termios tty;
    memset(&tty, 0, sizeof tty);
    if (tcgetattr(fd, &tty) != 0) {
      return -1;
    }
    if (cfsetospeed(&tty, speed) != 0) {
      return -1;
    }
    if (cfsetispeed(&tty, speed) != 0) {
      return -1;
    }
    tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8;
    tty.c_iflag &= ~IGNBRK;
    tty.c_iflag &= ~INLCR;
    tty.c_iflag &= ~ICRNL;
    tty.c_lflag = 0;
    tty.c_oflag = 0;
    tty.c_cc[VMIN] = 1;
    tty.c_cc[VTIME] = 5;
    tty.c_iflag &= ~(IXON | IXOFF | IXANY);
    tty.c_cflag |= (CLOCAL | CREAD);
    tty.c_cflag &= ~(PARENB | PARODD);
    tty.c_cflag &= ~CSTOPB;
    if (tcsetattr(fd, TCSANOW, &tty) != 0) {
      return -1;
    }
  }
  return fd;
}
```