user: Translate the below assembly code into C programming language:

```asm
<bitfill_unaligned_rev>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x18,%rsp
  mov    0x50(%rsp),%eax
  test   %eax,%eax
  jne    L86
L35:
  add    $0x18,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax)
L86:
  mov    %rsi,%rbx
  mov    $0xffffffffffffffff,%rsi
  mov    %edx,%r15d
  mov    %r8d,%r12d
  mov    %rdi,0x8(%rsp)
  mov    %rcx,%rbp
  mov    %r9d,%r13d
  call   <FB_SHIFT_HIGH@plt>
  mov    0x50(%rsp),%ecx
  xor    %edx,%edx
  mov    0x8(%rsp),%rdi
  mov    %rax,%r14
  mov    $0xffffffffffffffff,%rsi
  add    %r15d,%ecx
  mov    %ecx,%eax
  mov    %ecx,(%rsp)
  divl   0x58(%rsp)
  call   <FB_SHIFT_HIGH@plt>
  mov    (%rsp),%ecx
  not    %rax
  mov    %rax,%r8
  cmp    0x58(%rsp),%ecx
  ja     L3
  mov    %r14,%rax
  mov    (%rbx),%rsi
  mov    %rbp,%rdi
  and    %r8,%rax
  test   %r8,%r8
  cmovne %rax,%r14
  xor    %rsi,%rdi
  mov    %r14,%rdx
  call   <comp@plt>
  mov    %rax,(%rbx)
  add    $0x18,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   (%rax)
L3:
  test   %r14,%r14
  jne    L106
L96:
  mov    0x50(%rsp),%eax
  xor    %edx,%edx
  divl   0x58(%rsp)
  mov    %eax,%edx
  cmp    $0x3,%eax
  jbe    L43
  lea    -0x4(%rax),%r15d
  shr    $0x2,%r15d
  add    $0x1,%r15d
  shl    $0x5,%r15
  add    %rbx,%r15
  nopl   0x0(%rax)
L2:
  mov    %rbp,%rdi
  mov    %r12d,%ecx
  xor    %rbp,(%rbx)
  shl    %cl,%rdi
  mov    %r13d,%ecx
  shr    %cl,%rbp
  mov    %r12d,%ecx
  or     %rbp,%rdi
  xor    %rdi,0x8(%rbx)
  mov    %rdi,%rbp
  shl    %cl,%rbp
  mov    %r13d,%ecx
  shr    %cl,%rdi
  mov    %r12d,%ecx
  or     %rdi,%rbp
  xor    %rbp,0x10(%rbx)
  add    $0x20,%rbx
  mov    %rbp,%rdx
  shl    %cl,%rdx
  mov    %r13d,%ecx
  shr    %cl,%rbp
  mov    %r12d,%ecx
  or     %rbp,%rdx
  xor    %rdx,-0x8(%rbx)
  mov    %rdx,%rbp
  shl    %cl,%rbp
  mov    %r13d,%ecx
  shr    %cl,%rdx
  or     %rdx,%rbp
  cmp    %r15,%rbx
  jne    L2
  and    $0x3,%eax
  mov    %eax,%edx
L5:
  lea    -0x1(%rdx),%eax
  test   %edx,%edx
  je     L82
  mov    (%r15),%rdx
L60:
  mov    %rbp,%rsi
  mov    %r12d,%ecx
  xor    %rbp,%rdx
  shl    %cl,%rsi
  mov    %r13d,%ecx
  shr    %cl,%rbp
  or     %rsi,%rbp
  sub    $0x1,%eax
  jae    L60
  mov    %rdx,(%r15)
L82:
  test   %r8,%r8
  je     L35
  mov    (%r15),%rsi
  mov    %rbp,%rdi
  mov    %r8,%rdx
  xor    %rsi,%rdi
  call   <comp@plt>
  mov    %rax,(%r15)
  jmp    L35
  xchg   %ax,%ax
L106:
  mov    (%rbx),%rsi
  mov    %r14,%rdx
  mov    %rax,(%rsp)
  add    $0x8,%rbx
  mov    %rsi,%rdi
  xor    %rbp,%rdi
  call   <comp@plt>
  mov    %r12d,%ecx
  mov    (%rsp),%r8
  mov    %rax,-0x8(%rbx)
  mov    %rbp,%rax
  shl    %cl,%rax
  mov    %r13d,%ecx
  shr    %cl,%rbp
  or     %rax,%rbp
  mov    0x58(%rsp),%eax
  sub    %r15d,%eax
  sub    %eax,0x50(%rsp)
  jmp    L96
  nopl   0x0(%rax,%rax,1)
L43:
  mov    %rbx,%r15
  jmp    L5
```

assistant: ```c
void bitfill_unaligned_rev(struct fb_info *p, unsigned long *dst, int dst_idx, unsigned long pat, int left, int right, unsigned n, int bits) {
  unsigned long first, last;
  if (!n)
    return;
  first = FB_SHIFT_HIGH(p, ~0UL, dst_idx);
  last = ~(FB_SHIFT_HIGH(p, ~0UL, (dst_idx + n) % bits));
  if (dst_idx + n <= bits) {
    if (last)
      first &= last;
    *dst = comp(*dst ^ pat, *dst, first);
  } else {
    if (first != 0UL) {
      *dst = comp(*dst ^ pat, *dst, first);
      dst++;
      pat = pat << left | pat >> right;
      n -= bits - dst_idx;
    }
    n /= bits;
    while (n >= 4) {
      *dst++ ^= pat;
      pat = pat << left | pat >> right;
      *dst++ ^= pat;
      pat = pat << left | pat >> right;
      *dst++ ^= pat;
      pat = pat << left | pat >> right;
      *dst++ ^= pat;
      pat = pat << left | pat >> right;
      n -= 4;
    }
    while (n--) {
      *dst ^= pat;
      pat = pat << left | pat >> right;
    }
    if (last)
      *dst = comp(*dst ^ pat, *dst, last);
  }
}
```