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

```asm
<tpenc16>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %rdi,-0x38(%rbp)
  mov    %esi,-0x3c(%rbp)
  mov    %rdx,-0x48(%rbp)
  mov    -0x3c(%rbp),%eax
  shr    $0x4,%eax
  mov    %eax,-0x24(%rbp)
  mov    -0x3c(%rbp),%eax
  and    $0xfffffff0,%eax
  mov    %rax,%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x10(%rbp)
  mov    -0x38(%rbp),%rax
  mov    %rax,-0x18(%rbp)
  mov    -0x48(%rbp),%rax
  mov    %rax,-0x20(%rbp)
  jmp    L36
L13:
  mov    -0x20(%rbp),%rax
  mov    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x1(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x2(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x3(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x4(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x5(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x6(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x7(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x8(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0x9(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0xa(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0xb(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0xc(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0xd(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0xe(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%eax
  add    %rax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl 0xf(%rax),%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  addq   $0x1,-0x20(%rbp)
  addq   $0x10,-0x18(%rbp)
L36:
  mov    -0x18(%rbp),%rax
  cmp    -0x10(%rbp),%rax
  jb     L13
  mov    -0x24(%rbp),%eax
  shl    $0x4,%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x20(%rbp)
  jmp    L27
L31:
  mov    -0x18(%rbp),%rdx
  lea    0x1(%rdx),%rax
  mov    %rax,-0x18(%rbp)
  mov    -0x20(%rbp),%rax
  lea    0x1(%rax),%rcx
  mov    %rcx,-0x20(%rbp)
  movzbl (%rdx),%edx
  mov    %dl,(%rax)
L27:
  mov    -0x3c(%rbp),%edx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  cmp    %rax,-0x18(%rbp)
  jb     L31
  nop
  nop
  pop    %rbp
  ret
```

assistant: ```c
void tpenc16(unsigned char *in, unsigned n, unsigned char *out) {
  unsigned char *op, *ip, *e;
  unsigned stride = n / 16;
  e = in + (n & ~(16 - 1));
  for (ip = in, op = out; ip < e; op++, ip += 16) {
    unsigned char *p = op;
    p[0] = ip[0];
    *(p += stride) = ip[1];
    *(p += stride) = ip[2];
    *(p += stride) = ip[3];
    *(p += stride) = ip[4];
    *(p += stride) = ip[5];
    *(p += stride) = ip[6];
    *(p += stride) = ip[7];
    *(p += stride) = ip[8];
    *(p += stride) = ip[9];
    *(p += stride) = ip[10];
    *(p += stride) = ip[11];
    *(p += stride) = ip[12];
    *(p += stride) = ip[13];
    *(p += stride) = ip[14];
    *(p += stride) = ip[15];
  }
  for (op = out + stride * 16; ip < in + n;)
    *op++ = *ip++;
}
```