user: 提供的汇编代码用C语言表示会是什么样子：

```asm
<CAST_cfb64_encrypt>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %r13
  push   %r12
  push   %rbx
  sub    $0x68,%rsp
  mov    %rdi,-0x58(%rbp)
  mov    %rsi,-0x60(%rbp)
  mov    %rdx,-0x68(%rbp)
  mov    %rcx,-0x70(%rbp)
  mov    %r8,-0x78(%rbp)
  mov    %r9,-0x80(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x28(%rbp)
  xor    %eax,%eax
  mov    -0x80(%rbp),%rax
  mov    (%rax),%r12d
  mov    -0x68(%rbp),%r13
  mov    -0x78(%rbp),%rax
  mov    %rax,-0x48(%rbp)
  cmpl   $0x0,0x10(%rbp)
  je     L33
  jmp    L36
L8:
  test   %r12d,%r12d
  jne    L73
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x18,%rax
  mov    %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x10,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x8,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  or     %rax,%rbx
  mov    %rbx,-0x40(%rbp)
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x18,%rax
  mov    %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x10,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x8,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  or     %rax,%rbx
  mov    %rbx,-0x38(%rbp)
  mov    -0x70(%rbp),%rdx
  lea    -0x40(%rbp),%rax
  mov    %rdx,%rsi
  mov    %rax,%rdi
  call   <CAST_encrypt@plt>
  mov    -0x78(%rbp),%rax
  mov    %rax,-0x48(%rbp)
  mov    -0x40(%rbp),%rbx
  mov    %rbx,%rcx
  shr    $0x18,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x10,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x8,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ebx,%edx
  mov    %dl,(%rax)
  mov    -0x38(%rbp),%rbx
  mov    %rbx,%rcx
  shr    $0x18,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x10,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x8,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ebx,%edx
  mov    %dl,(%rax)
  mov    -0x78(%rbp),%rax
  mov    %rax,-0x48(%rbp)
L73:
  mov    -0x58(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x58(%rbp)
  movzbl (%rax),%edx
  movslq %r12d,%rcx
  mov    -0x48(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rax),%eax
  xor    %edx,%eax
  mov    %al,-0x49(%rbp)
  mov    -0x60(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x60(%rbp)
  movzbl -0x49(%rbp),%edx
  mov    %dl,(%rax)
  movslq %r12d,%rdx
  mov    -0x48(%rbp),%rax
  add    %rax,%rdx
  movzbl -0x49(%rbp),%eax
  mov    %al,(%rdx)
  lea    0x1(%r12),%eax
  and    $0x7,%eax
  mov    %eax,%r12d
L36:
  mov    %r13,%rax
  lea    -0x1(%rax),%r13
  test   %rax,%rax
  jne    L8
  jmp    L7
L66:
  test   %r12d,%r12d
  jne    L55
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x18,%rax
  mov    %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x10,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x8,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  or     %rax,%rbx
  mov    %rbx,-0x40(%rbp)
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x18,%rax
  mov    %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x10,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  shl    $0x8,%rax
  or     %rax,%rbx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  movzbl (%rax),%eax
  movzbl %al,%eax
  or     %rax,%rbx
  mov    %rbx,-0x38(%rbp)
  mov    -0x70(%rbp),%rdx
  lea    -0x40(%rbp),%rax
  mov    %rdx,%rsi
  mov    %rax,%rdi
  call   <CAST_encrypt@plt>
  mov    -0x78(%rbp),%rax
  mov    %rax,-0x48(%rbp)
  mov    -0x40(%rbp),%rbx
  mov    %rbx,%rcx
  shr    $0x18,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x10,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x8,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ebx,%edx
  mov    %dl,(%rax)
  mov    -0x38(%rbp),%rbx
  mov    %rbx,%rcx
  shr    $0x18,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x10,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    %rbx,%rcx
  shr    $0x8,%rcx
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x48(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x48(%rbp)
  mov    %ebx,%edx
  mov    %dl,(%rax)
  mov    -0x78(%rbp),%rax
  mov    %rax,-0x48(%rbp)
L55:
  mov    -0x58(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x58(%rbp)
  movzbl (%rax),%eax
  mov    %al,-0x4a(%rbp)
  movslq %r12d,%rdx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  mov    %al,-0x49(%rbp)
  movslq %r12d,%rdx
  mov    -0x48(%rbp),%rax
  add    %rax,%rdx
  movzbl -0x4a(%rbp),%eax
  mov    %al,(%rdx)
  mov    -0x60(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x60(%rbp)
  movzbl -0x49(%rbp),%edx
  xor    -0x4a(%rbp),%dl
  mov    %dl,(%rax)
  lea    0x1(%r12),%eax
  and    $0x7,%eax
  mov    %eax,%r12d
L33:
  mov    %r13,%rax
  lea    -0x1(%rax),%r13
  test   %rax,%rax
  jne    L66
L7:
  movb   $0x0,-0x4a(%rbp)
  movzbl -0x4a(%rbp),%eax
  mov    %al,-0x49(%rbp)
  movzbl -0x49(%rbp),%ebx
  mov    %rbx,-0x38(%rbp)
  mov    -0x38(%rbp),%rax
  mov    %rax,-0x40(%rbp)
  mov    -0x80(%rbp),%rax
  mov    %r12d,(%rax)
  nop
  mov    -0x28(%rbp),%rax
  sub    %fs:0x28,%rax
  je     L60
  call   <__stack_chk_fail@plt>
L60:
  add    $0x68,%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %rbp
  ret
```

assistant: ```c
void CAST_cfb64_encrypt(const unsigned char *in, unsigned char *out, long length, const CAST_KEY *schedule, unsigned char *ivec, int *num, int enc) {
  register CAST_LONG v0, v1, t;
  register int n = *num;
  register long l = length;
  CAST_LONG ti[2];
  unsigned char *iv, c, cc;
  iv = ivec;
  if (enc) {
    while (l--) {
      if (n == 0) {
        (v0 = ((unsigned long)(*((iv)++))) << 24L, v0 |= ((unsigned long)(*((iv)++))) << 16L, v0 |= ((unsigned long)(*((iv)++))) << 8L, v0 |= ((unsigned long)(*((iv)++))));
        ti[0] = v0;
        (v1 = ((unsigned long)(*((iv)++))) << 24L, v1 |= ((unsigned long)(*((iv)++))) << 16L, v1 |= ((unsigned long)(*((iv)++))) << 8L, v1 |= ((unsigned long)(*((iv)++))));
        ti[1] = v1;
        CAST_encrypt((CAST_LONG *)ti, schedule);
        iv = ivec;
        t = ti[0];
        (*((iv)++) = (unsigned char)(((t) >> 24L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 16L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 8L) & 0xff), *((iv)++) = (unsigned char)(((t)) & 0xff));
        t = ti[1];
        (*((iv)++) = (unsigned char)(((t) >> 24L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 16L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 8L) & 0xff), *((iv)++) = (unsigned char)(((t)) & 0xff));
        iv = ivec;
      }
      c = *(in++) ^ iv[n];
      *(out++) = c;
      iv[n] = c;
      n = (n + 1) & 0x07;
    }
  } else {
    while (l--) {
      if (n == 0) {
        (v0 = ((unsigned long)(*((iv)++))) << 24L, v0 |= ((unsigned long)(*((iv)++))) << 16L, v0 |= ((unsigned long)(*((iv)++))) << 8L, v0 |= ((unsigned long)(*((iv)++))));
        ti[0] = v0;
        (v1 = ((unsigned long)(*((iv)++))) << 24L, v1 |= ((unsigned long)(*((iv)++))) << 16L, v1 |= ((unsigned long)(*((iv)++))) << 8L, v1 |= ((unsigned long)(*((iv)++))));
        ti[1] = v1;
        CAST_encrypt((CAST_LONG *)ti, schedule);
        iv = ivec;
        t = ti[0];
        (*((iv)++) = (unsigned char)(((t) >> 24L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 16L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 8L) & 0xff), *((iv)++) = (unsigned char)(((t)) & 0xff));
        t = ti[1];
        (*((iv)++) = (unsigned char)(((t) >> 24L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 16L) & 0xff), *((iv)++) = (unsigned char)(((t) >> 8L) & 0xff), *((iv)++) = (unsigned char)(((t)) & 0xff));
        iv = ivec;
      }
      cc = *(in++);
      c = iv[n];
      iv[n] = cc;
      *(out++) = c ^ cc;
      n = (n + 1) & 0x07;
    }
  }
  v0 = v1 = ti[0] = ti[1] = t = c = cc = 0;
  *num = n;
}
```