user: Demonstrate the C code that generates the assembly output below:

```asm
<difftimespec>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x50,%rsp
  mov    %rdi,-0x38(%rbp)
  mov    %rsi,-0x40(%rbp)
  mov    %rdx,-0x48(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x8(%rbp)
  xor    %eax,%eax
  mov    -0x38(%rbp),%rax
  mov    0x8(%rax),%rdx
  mov    (%rax),%rax
  mov    %rax,-0x30(%rbp)
  mov    %rdx,-0x28(%rbp)
  mov    -0x40(%rbp),%rax
  mov    0x8(%rax),%rdx
  mov    (%rax),%rax
  mov    %rax,-0x20(%rbp)
  mov    %rdx,-0x18(%rbp)
  mov    -0x30(%rbp),%rdx
  mov    -0x20(%rbp),%rax
  cmp    %rax,%rdx
  jne    L29
  mov    -0x48(%rbp),%rax
  movq   $0x0,(%rax)
  mov    -0x18(%rbp),%eax
  mov    -0x28(%rbp),%edx
  sub    %edx,%eax
  mov    %eax,%edi
  call   <labs@plt>
  mov    -0x48(%rbp),%rdx
  mov    %eax,0x8(%rdx)
  mov    -0x18(%rbp),%eax
  mov    -0x28(%rbp),%edx
  sub    %edx,%eax
  jmp    L34
L29:
  mov    -0x30(%rbp),%rdx
  mov    -0x20(%rbp),%rax
  cmp    %rax,%rdx
  jge    L5
  mov    -0x20(%rbp),%rax
  mov    -0x30(%rbp),%rcx
  sub    %rcx,%rax
  mov    %rax,%rdx
  mov    -0x48(%rbp),%rax
  mov    %rdx,(%rax)
  mov    -0x18(%rbp),%eax
  mov    -0x28(%rbp),%ecx
  sub    %ecx,%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  mov    %edx,0x8(%rax)
  mov    -0x48(%rbp),%rax
  mov    0x8(%rax),%eax
  test   %eax,%eax
  jns    L30
  mov    -0x48(%rbp),%rax
  mov    (%rax),%rax
  lea    -0x1(%rax),%rdx
  mov    -0x48(%rbp),%rax
  mov    %rdx,(%rax)
  mov    -0x48(%rbp),%rax
  mov    0x8(%rax),%eax
  add    $0x3b9aca00,%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  mov    %edx,0x8(%rax)
L30:
  mov    $0x1,%eax
  jmp    L34
L5:
  mov    -0x30(%rbp),%rax
  mov    -0x20(%rbp),%rcx
  sub    %rcx,%rax
  mov    %rax,%rdx
  mov    -0x48(%rbp),%rax
  mov    %rdx,(%rax)
  mov    -0x28(%rbp),%eax
  mov    -0x18(%rbp),%ecx
  sub    %ecx,%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  mov    %edx,0x8(%rax)
  mov    -0x48(%rbp),%rax
  mov    0x8(%rax),%eax
  test   %eax,%eax
  jns    L15
  mov    -0x48(%rbp),%rax
  mov    (%rax),%rax
  lea    -0x1(%rax),%rdx
  mov    -0x48(%rbp),%rax
  mov    %rdx,(%rax)
  mov    -0x48(%rbp),%rax
  mov    0x8(%rax),%eax
  add    $0x3b9aca00,%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  mov    %edx,0x8(%rax)
L15:
  mov    $0xffffffff,%eax
L34:
  mov    -0x8(%rbp),%rdx
  sub    %fs:0x28,%rdx
  je     L45
  call   <__stack_chk_fail@plt>
L45:
  leave
  ret
```

assistant: ```c
int difftimespec(const struct timespec *ts1, const struct timespec *ts2, struct timespec *ts) {
  const struct timespec _ts1 = *ts1;
  const struct timespec _ts2 = *ts2;
  if (_ts1.tv_sec == _ts2.tv_sec) {
    ts->tv_sec = 0;
    ts->tv_nsec = labs(_ts2.tv_nsec - _ts1.tv_nsec);
    return _ts2.tv_nsec - _ts1.tv_nsec;
  }
  if (_ts1.tv_sec < _ts2.tv_sec) {
    do {
      (ts)->tv_sec = (&_ts2)->tv_sec - (&_ts1)->tv_sec;
      (ts)->tv_nsec = (&_ts2)->tv_nsec - (&_ts1)->tv_nsec;
      if ((ts)->tv_nsec < 0) {
        (ts)->tv_sec--;
        (ts)->tv_nsec += 1000000000L;
      }
    } while (0);
    return 1;
  }
  do {
    (ts)->tv_sec = (&_ts1)->tv_sec - (&_ts2)->tv_sec;
    (ts)->tv_nsec = (&_ts1)->tv_nsec - (&_ts2)->tv_nsec;
    if ((ts)->tv_nsec < 0) {
      (ts)->tv_sec--;
      (ts)->tv_nsec += 1000000000L;
    }
  } while (0);
  return -1;
}
```