user: 请显示与下面列出的汇编代码相匹配的C语言实现：

```asm
<unpack>:
  endbr64
  push   %rbp
  mov    %rdi,%r11
  mov    %rsp,%rbp
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  mov    %rsi,%r12
  push   %rbx
  sub    $0x18,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,-0x38(%rbp)
  xor    %eax,%eax
  movslq %edx,%rax
  mov    %rsp,%rsi
  lea    0xf(,%rax,4),%rax
  mov    %rax,%rcx
  and    $0xfffffffffffff000,%rax
  sub    %rax,%rsi
  and    $0xfffffffffffffff0,%rcx
  cmp    %rsi,%rsp
  je     L89
L103:
  sub    $0x1000,%rsp
  orq    $0x0,0xff8(%rsp)
  cmp    %rsi,%rsp
  jne    L103
L89:
  and    $0xfff,%ecx
  sub    %rcx,%rsp
  test   %rcx,%rcx
  jne    L95
L107:
  mov    %rsp,%rbx
  test   %edx,%edx
  jle    L162
  lea    -0x1(%rdx),%r13d
  cmp    $0x2,%r13d
  jbe    L40
  mov    %edx,%ecx
  movdqa D4(%rip),%xmm1
  movdqa D20(%rip),%xmm4
  mov    %rbx,%rax
  shr    $0x2,%ecx
  movdqa D11(%rip),%xmm3
  movdqa D12(%rip),%xmm2
  shl    $0x4,%rcx
  add    %rbx,%rcx
  nopl   0x0(%rax)
L148:
  movdqa %xmm1,%xmm0
  add    $0x10,%rax
  paddd  %xmm4,%xmm1
  pand   %xmm3,%xmm0
  paddd  %xmm2,%xmm0
  movups %xmm0,-0x10(%rax)
  cmp    %rax,%rcx
  jne    L148
  mov    %edx,%ecx
  and    $0xfffffffc,%ecx
  test   $0x3,%dl
  je     L46
L11:
  movslq %ecx,%rax
  lea    (%rbx,%rax,4),%rsi
  lea    0x1(%rcx),%eax
  movl   $0x9,(%rsi)
  cmp    %eax,%edx
  jle    L46
  and    $0x1,%eax
  add    $0x2,%ecx
  add    $0x9,%eax
  mov    %eax,0x4(%rsi)
  cmp    %edx,%ecx
  jge    L46
  movl   $0x9,0x8(%rsi)
L46:
  mov    %edx,%edx
  mov    %r11,%rdi
  lea    0x1(%r12,%r13,1),%r14
  xor    %esi,%esi
  add    %rdx,%rdx
  call   <memset@plt>
  mov    %r12,%rsi
  xor    %r9d,%r9d
  xor    %r10d,%r10d
  movzwl (%rax),%edi
  mov    %rax,%r11
  jmp    L19
  nopw   0x0(%rax,%rax,1)
L88:
  mov    $0x8,%r13d
  mov    $0xff,%r15d
  sub    %eax,%r13d
  mov    %r13d,%ecx
  sar    %cl,%r15d
  mov    %r9d,%ecx
  mov    %r13d,%r9d
  and    %r15d,%r8d
  shl    %cl,%r8d
  add    %edi,%r8d
  mov    %r8w,(%r12)
L50:
  movzbl (%rsi),%edi
  lea    0x2(%r11,%rdx,1),%rdx
  mov    %eax,%ecx
  add    $0x1,%rsi
  add    $0x1,%r10d
  sar    %cl,%edi
  add    (%rdx),%di
  mov    %di,(%rdx)
  cmp    %rsi,%r14
  je     L162
L19:
  movslq %r10d,%rdx
  movzbl (%rsi),%r8d
  mov    (%rbx,%rdx,4),%eax
  add    %rdx,%rdx
  lea    (%r11,%rdx,1),%r12
  sub    %r9d,%eax
  cmp    $0x7,%eax
  jle    L88
  mov    %r9d,%ecx
  shl    %cl,%r8d
  add    %r8d,%edi
  mov    %di,(%r12)
  cmp    $0x8,%eax
  je     L0
  add    $0x1,%rsi
  add    $0x8,%r9d
  cmp    %rsi,%r14
  jne    L19
L162:
  mov    -0x38(%rbp),%rax
  sub    %fs:0x28,%rax
  jne    L131
  lea    -0x28(%rbp),%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  pop    %rbp
  ret
  nop
L95:
  orq    $0x0,-0x8(%rsp,%rcx,1)
  jmp    L107
L40:
  xor    %ecx,%ecx
  jmp    L11
L131:
  call   <__stack_chk_fail@plt>
L0:
  xor    %r9d,%r9d
  jmp    L50
```

tool_calls: name: extract_symbolic_data
arguments: data_label: D4
type: byte[16]
name: extract_symbolic_data
arguments: data_label: D20
type: byte[16]
name: extract_symbolic_data
arguments: data_label: D11
type: byte[16]
name: extract_symbolic_data
arguments: data_label: D12
type: byte[16]

tool: {"D4": [0x00,0x00,0x00,0x00,0x01,0x00,0x00,0x00,0x02,0x00,0x00,0x00,0x03,0x00,0x00,0x00]}

tool: {"D20": [0x04,0x00,0x00,0x00,0x04,0x00,0x00,0x00,0x04,0x00,0x00,0x00,0x04,0x00,0x00,0x00]}

tool: {"D11": [0x01,0x00,0x00,0x00,0x01,0x00,0x00,0x00,0x01,0x00,0x00,0x00,0x01,0x00,0x00,0x00]}

tool: {"D12": [0x09,0x00,0x00,0x00,0x09,0x00,0x00,0x00,0x09,0x00,0x00,0x00,0x09,0x00,0x00,0x00]}

assistant: ```c
void unpack(unsigned short *tgt, unsigned char *src, int len) {
  int x, y, z;
  int n, temp;
  int buffer[len];
  for (x = 0; x < len; tgt[x++] = 0)
    buffer[x] = 9 + (x & 1);
  for (x = y = z = 0; x < len; x++) {
    n = buffer[y] - z;
    temp = src[x];
    if (n < 8)
      temp &= 255 >> (8 - n);
    tgt[y] += temp << z;
    if (n <= 8) {
      tgt[++y] += src[x] >> n;
      z = 8 - n;
    } else
      z += 8;
  }
}
```