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

```asm
<Camellia_cfbr_encrypt_block>:
  endbr64
  push   %rbp
  mov    %rcx,%r11
  mov    %rdi,%r10
  mov    %rsp,%rbp
  push   %r15
  push   %r14
  mov    %rsi,%r14
  push   %r13
  push   %r12
  mov    %r8,%r12
  push   %rbx
  mov    %edx,%ebx
  sub    $0x38,%rsp
  mov    D9(%rip),%r13
  mov    %fs:0x28,%rax
  mov    %rax,-0x38(%rbp)
  xor    %eax,%eax
  mov    %rsp,%rsi
  mov    %rsp,%r15
  mov    0x0(%r13),%edx
  lea    (%rdx,%rdx,1),%eax
  cltq
  add    $0xf,%rax
  mov    %rax,%rcx
  and    $0xfffffffffffff000,%rax
  sub    %rax,%rsi
  and    $0xfffffffffffffff0,%rcx
  cmp    %rsi,%rsp
  je     L261
L85:
  sub    $0x1000,%rsp
  orq    $0x0,0xff8(%rsp)
  cmp    %rsi,%rsp
  jne    L85
L261:
  and    $0xfff,%ecx
  sub    %rcx,%rsp
  test   %rcx,%rcx
  jne    L347
  lea    -0x1(%rbx),%eax
  mov    %rsp,%r8
  cmp    $0x7f,%eax
  jbe    L363
  nopl   0x0(%rax,%rax,1)
L358:
  mov    %r15,%rsp
  mov    -0x38(%rbp),%rax
  sub    %fs:0x28,%rax
  jne    L99
  lea    -0x28(%rbp),%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  pop    %rbp
  ret
  nopl   (%rax)
L363:
  mov    %r12,%rsi
  mov    %rsp,%rdi
  mov    %r9d,-0x5c(%rbp)
  mov    %r10,-0x50(%rbp)
  mov    %r8,-0x48(%rbp)
  mov    %r11,-0x58(%rbp)
  call   <memcpy@plt>
  mov    -0x58(%rbp),%rdx
  mov    %r12,%rsi
  mov    %r12,%rdi
  call   <Camellia_encrypt@plt>
  mov    -0x5c(%rbp),%r9d
  lea    0x7(%rbx),%eax
  mov    -0x48(%rbp),%r8
  sar    $0x3,%eax
  mov    -0x50(%rbp),%r10
  test   %r9d,%r9d
  je     L183
  movslq 0x0(%r13),%rcx
  movzbl (%r12),%edx
  xor    (%r10),%dl
  mov    %dl,(%rsp,%rcx,1)
  mov    %dl,(%r14)
  cmp    $0x1,%eax
  je     L224
  mov    0x0(%r13),%edi
  movzbl 0x1(%r12),%ecx
  xor    0x1(%r10),%cl
  lea    0x1(%rdi),%edx
  mov    %cl,0x1(%r14)
  movslq %edx,%rdx
  mov    %cl,(%rsp,%rdx,1)
  cmp    $0x2,%eax
  je     L224
  mov    0x0(%r13),%edi
  movzbl 0x2(%r12),%ecx
  xor    0x2(%r10),%cl
  lea    0x2(%rdi),%edx
  mov    %cl,0x2(%r14)
  movslq %edx,%rdx
  mov    %cl,(%rsp,%rdx,1)
  cmp    $0x3,%eax
  je     L224
  mov    0x0(%r13),%edi
  movzbl 0x3(%r12),%ecx
  xor    0x3(%r10),%cl
  lea    0x3(%rdi),%edx
  mov    %cl,0x3(%r14)
  movslq %edx,%rdx
  mov    %cl,(%rsp,%rdx,1)
  cmp    $0x4,%eax
  je     L224
  mov    0x0(%r13),%edx
  movzbl 0x4(%r10),%ecx
  xor    0x4(%r12),%cl
  lea    0x4(%rdx),%esi
  mov    %cl,0x4(%r14)
  movslq %esi,%rsi
  mov    %cl,(%rsp,%rsi,1)
  cmp    $0x5,%eax
  je     L224
  lea    0x5(%rdx),%esi
  movzbl 0x5(%r10),%ecx
  xor    0x5(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0x5(%r14)
  mov    %cl,(%rsp,%rsi,1)
  cmp    $0x6,%eax
  je     L224
  lea    0x6(%rdx),%esi
  movzbl 0x6(%r10),%ecx
  xor    0x6(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0x6(%r14)
  mov    %cl,(%rsp,%rsi,1)
  cmp    $0x7,%eax
  je     L224
  lea    0x7(%rdx),%esi
  movzbl 0x7(%r10),%ecx
  xor    0x7(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0x7(%r14)
  mov    %cl,(%rsp,%rsi,1)
  cmp    $0x8,%eax
  je     L224
  lea    0x8(%rdx),%esi
  movzbl 0x8(%r10),%ecx
  xor    0x8(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0x8(%r14)
  mov    %cl,(%r8,%rsi,1)
  cmp    $0x9,%eax
  je     L224
  lea    0x9(%rdx),%esi
  movzbl 0x9(%r10),%ecx
  xor    0x9(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0x9(%r14)
  mov    %cl,(%r8,%rsi,1)
  cmp    $0xa,%eax
  je     L224
  lea    0xa(%rdx),%esi
  movzbl 0xa(%r10),%ecx
  xor    0xa(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0xa(%r14)
  mov    %cl,(%r8,%rsi,1)
  cmp    $0xb,%eax
  je     L224
  lea    0xb(%rdx),%esi
  movzbl 0xb(%r10),%ecx
  xor    0xb(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0xb(%r14)
  mov    %cl,(%r8,%rsi,1)
  cmp    $0xc,%eax
  je     L224
  lea    0xc(%rdx),%esi
  movzbl 0xc(%r10),%ecx
  xor    0xc(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0xc(%r14)
  mov    %cl,(%r8,%rsi,1)
  cmp    $0xd,%eax
  je     L224
  lea    0xd(%rdx),%esi
  movzbl 0xd(%r10),%ecx
  xor    0xd(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0xd(%r14)
  mov    %cl,(%r8,%rsi,1)
  cmp    $0xe,%eax
  je     L224
  lea    0xe(%rdx),%esi
  movzbl 0xe(%r10),%ecx
  xor    0xe(%r12),%cl
  movslq %esi,%rsi
  mov    %cl,0xe(%r14)
  mov    %cl,(%r8,%rsi,1)
  cmp    $0x10,%eax
  jne    L224
  lea    0xf(%rdx),%eax
  movzbl 0xf(%r10),%ecx
  xor    0xf(%r12),%cl
  cltq
  mov    %cl,0xf(%r14)
  mov    %cl,(%r8,%rax,1)
  xchg   %ax,%ax
L224:
  mov    %ebx,%eax
  mov    0x0(%r13),%edx
  sar    $0x3,%eax
  and    $0x7,%ebx
  je     L328
  test   %edx,%edx
  jle    L358
  cltq
  mov    $0x8,%r9d
  add    %rax,%r8
  sub    %ebx,%r9d
  xor    %eax,%eax
  movzbl (%r8),%esi
  xchg   %ax,%ax
L165:
  mov    %ebx,%ecx
  shl    %cl,%esi
  mov    %r9d,%ecx
  mov    %esi,%edx
  movzbl 0x1(%r8,%rax,1),%esi
  mov    %esi,%edi
  sar    %cl,%edi
  or     %edi,%edx
  mov    %dl,(%r12,%rax,1)
  add    $0x1,%rax
  cmp    %eax,0x0(%r13)
  jg     L165
  jmp    L358
  nopl   0x0(%rax,%rax,1)
L183:
  movzbl (%r10),%edx
  movslq 0x0(%r13),%rcx
  mov    %dl,(%rsp,%rcx,1)
  xor    (%r12),%dl
  mov    %dl,(%r14)
  cmp    $0x1,%eax
  je     L224
  mov    0x0(%r13),%edi
  movzbl 0x1(%r10),%ecx
  lea    0x1(%rdi),%edx
  movslq %edx,%rdx
  mov    %cl,(%rsp,%rdx,1)
  xor    0x1(%r12),%cl
  mov    %cl,0x1(%r14)
  cmp    $0x2,%eax
  je     L224
  mov    0x0(%r13),%edi
  movzbl 0x2(%r10),%ecx
  lea    0x2(%rdi),%edx
  movslq %edx,%rdx
  mov    %cl,(%rsp,%rdx,1)
  xor    0x2(%r12),%cl
  mov    %cl,0x2(%r14)
  cmp    $0x3,%eax
  je     L224
  mov    0x0(%r13),%edi
  movzbl 0x3(%r10),%ecx
  lea    0x3(%rdi),%edx
  movslq %edx,%rdx
  mov    %cl,(%rsp,%rdx,1)
  xor    0x3(%r12),%cl
  mov    %cl,0x3(%r14)
  cmp    $0x4,%eax
  je     L224
  mov    0x0(%r13),%edx
  movzbl 0x4(%r10),%ecx
  lea    0x4(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%rsp,%rsi,1)
  xor    0x4(%r12),%cl
  mov    %cl,0x4(%r14)
  cmp    $0x5,%eax
  je     L224
  movzbl 0x5(%r10),%ecx
  lea    0x5(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%rsp,%rsi,1)
  xor    0x5(%r12),%cl
  mov    %cl,0x5(%r14)
  cmp    $0x6,%eax
  je     L224
  movzbl 0x6(%r10),%ecx
  lea    0x6(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%rsp,%rsi,1)
  xor    0x6(%r12),%cl
  mov    %cl,0x6(%r14)
  cmp    $0x7,%eax
  je     L224
  movzbl 0x7(%r10),%ecx
  lea    0x7(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%rsp,%rsi,1)
  xor    0x7(%r12),%cl
  mov    %cl,0x7(%r14)
  cmp    $0x8,%eax
  je     L224
  movzbl 0x8(%r10),%ecx
  lea    0x8(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%r8,%rsi,1)
  xor    0x8(%r12),%cl
  mov    %cl,0x8(%r14)
  cmp    $0x9,%eax
  je     L224
  movzbl 0x9(%r10),%ecx
  lea    0x9(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%r8,%rsi,1)
  xor    0x9(%r12),%cl
  mov    %cl,0x9(%r14)
  cmp    $0xa,%eax
  je     L224
  movzbl 0xa(%r10),%ecx
  lea    0xa(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%r8,%rsi,1)
  xor    0xa(%r12),%cl
  mov    %cl,0xa(%r14)
  cmp    $0xb,%eax
  je     L224
  movzbl 0xb(%r10),%ecx
  lea    0xb(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%r8,%rsi,1)
  xor    0xb(%r12),%cl
  mov    %cl,0xb(%r14)
  cmp    $0xc,%eax
  je     L224
  movzbl 0xc(%r10),%ecx
  lea    0xc(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%r8,%rsi,1)
  xor    0xc(%r12),%cl
  mov    %cl,0xc(%r14)
  cmp    $0xd,%eax
  je     L224
  movzbl 0xd(%r10),%ecx
  lea    0xd(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%r8,%rsi,1)
  xor    0xd(%r12),%cl
  mov    %cl,0xd(%r14)
  cmp    $0xe,%eax
  je     L224
  movzbl 0xe(%r10),%ecx
  lea    0xe(%rdx),%esi
  movslq %esi,%rsi
  mov    %cl,(%r8,%rsi,1)
  xor    0xe(%r12),%cl
  mov    %cl,0xe(%r14)
  cmp    $0x10,%eax
  jne    L224
  movzbl 0xf(%r10),%ecx
  lea    0xf(%rdx),%eax
  cltq
  mov    %cl,(%r8,%rax,1)
  xor    0xf(%r12),%cl
  mov    %cl,0xf(%r14)
  jmp    L224
  nopw   0x0(%rax,%rax,1)
L347:
  orq    $0x0,-0x8(%rsp,%rcx,1)
  lea    -0x1(%rbx),%eax
  mov    %rsp,%r8
  cmp    $0x7f,%eax
  ja     L358
  jmp    L363
  nopw   0x0(%rax,%rax,1)
L328:
  cltq
  mov    %r12,%rdi
  lea    (%r8,%rax,1),%rsi
  call   <memcpy@plt>
  jmp    L358
L99:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
void Camellia_cfbr_encrypt_block(const unsigned char *in, unsigned char *out, const int nbits, const CAMELLIA_KEY *key, unsigned char *ivec, const int enc) {
  int n, rem, num;
  unsigned char ovec[CAMELLIA_BLOCK_SIZE * 2];
  if (nbits <= 0 || nbits > 128)
    return;
  memcpy(ovec, ivec, CAMELLIA_BLOCK_SIZE);
  Camellia_encrypt(ivec, ivec, key);
  num = (nbits + 7) / 8;
  if (enc)
    for (n = 0; n < num; ++n)
      out[n] = (ovec[CAMELLIA_BLOCK_SIZE + n] = in[n] ^ ivec[n]);
  else
    for (n = 0; n < num; ++n)
      out[n] = (ovec[CAMELLIA_BLOCK_SIZE + n] = in[n]) ^ ivec[n];
  rem = nbits % 8;
  num = nbits / 8;
  if (rem == 0)
    memcpy(ivec, ovec + num, CAMELLIA_BLOCK_SIZE);
  else
    for (n = 0; n < CAMELLIA_BLOCK_SIZE; ++n)
      ivec[n] = ovec[n + num] << rem | ovec[n + num + 1] >> (8 - rem);
}
```