user: 请从给定的汇编指令推导出C源代码:

```asm
<BOB2>:
  endbr64
  mov    $0x1f,%ecx
  mov    $0x9e3779b9,%r9d
  mov    $0x9e3779b9,%r8d
  cmp    $0xb,%esi
  jbe    L22
  xchg   %ax,%ax
L26:
  movzbl 0x5(%rdi),%edx
  movzbl 0x6(%rdi),%eax
  shl    $0x8,%edx
  shl    $0x10,%eax
  add    %eax,%edx
  movzbl 0x4(%rdi),%eax
  add    %eax,%edx
  movzbl 0x7(%rdi),%eax
  shl    $0x18,%eax
  add    %eax,%edx
  movzbl 0x9(%rdi),%eax
  add    %r9d,%edx
  movzbl 0xa(%rdi),%r9d
  shl    $0x8,%eax
  shl    $0x10,%r9d
  add    %r9d,%eax
  movzbl 0x8(%rdi),%r9d
  add    %r9d,%eax
  movzbl 0xb(%rdi),%r9d
  shl    $0x18,%r9d
  add    %r9d,%eax
  movzbl 0x2(%rdi),%r9d
  add    %ecx,%eax
  movzbl 0x1(%rdi),%ecx
  shl    $0x10,%r9d
  shl    $0x8,%ecx
  add    %r9d,%ecx
  movzbl (%rdi),%r9d
  add    %r9d,%ecx
  movzbl 0x3(%rdi),%r9d
  shl    $0x18,%r9d
  add    %r9d,%ecx
  sub    %edx,%ecx
  sub    %eax,%edx
  sub    %eax,%ecx
  add    %r8d,%ecx
  mov    %eax,%r8d
  shr    $0xd,%r8d
  xor    %r8d,%ecx
  sub    %ecx,%edx
  sub    %ecx,%eax
  mov    %edx,%r8d
  mov    %ecx,%edx
  shl    $0x8,%edx
  xor    %r8d,%edx
  sub    %edx,%eax
  mov    %eax,%r8d
  mov    %edx,%eax
  shr    $0xd,%eax
  xor    %r8d,%eax
  sub    %edx,%ecx
  sub    $0xc,%esi
  add    $0xc,%rdi
  sub    %eax,%ecx
  sub    %eax,%edx
  mov    %ecx,%r8d
  mov    %eax,%ecx
  shr    $0xc,%ecx
  xor    %r8d,%ecx
  sub    %ecx,%edx
  sub    %ecx,%eax
  mov    %edx,%r8d
  mov    %ecx,%edx
  shl    $0x10,%edx
  xor    %r8d,%edx
  sub    %edx,%eax
  sub    %edx,%ecx
  mov    %eax,%r8d
  mov    %edx,%eax
  shr    $0x5,%eax
  xor    %r8d,%eax
  mov    %eax,%r8d
  sub    %eax,%ecx
  sub    %eax,%edx
  shr    $0x3,%r8d
  xor    %ecx,%r8d
  mov    %r8d,%r9d
  sub    %r8d,%edx
  sub    %r8d,%eax
  shl    $0xa,%r9d
  xor    %edx,%r9d
  mov    %r9d,%ecx
  sub    %r9d,%eax
  shr    $0xf,%ecx
  xor    %eax,%ecx
  cmp    $0xb,%esi
  ja     L26
L22:
  add    %esi,%ecx
  cmp    $0xb,%esi
  ja     L9
  lea    D7(%rip),%rdx
  mov    %esi,%esi
  movslq (%rdx,%rsi,4),%rax
  add    %rdx,%rax
  notrack jmp *%rax
  nopw   0x0(%rax,%rax,1)
  movzbl 0xa(%rdi),%eax
  shl    $0x18,%eax
  add    %eax,%ecx
  movzbl 0x9(%rdi),%eax
  shl    $0x10,%eax
  add    %eax,%ecx
  movzbl 0x8(%rdi),%eax
  shl    $0x8,%eax
  add    %eax,%ecx
  movzbl 0x7(%rdi),%eax
  shl    $0x18,%eax
  add    %eax,%r9d
  movzbl 0x6(%rdi),%eax
  shl    $0x10,%eax
  add    %eax,%r9d
  movzbl 0x5(%rdi),%eax
  shl    $0x8,%eax
  add    %eax,%r9d
  movzbl 0x4(%rdi),%eax
  add    %eax,%r9d
  movzbl 0x3(%rdi),%eax
  shl    $0x18,%eax
  add    %eax,%r8d
  movzbl 0x2(%rdi),%eax
  shl    $0x10,%eax
  add    %eax,%r8d
  movzbl 0x1(%rdi),%eax
  shl    $0x8,%eax
  add    %eax,%r8d
  movzbl (%rdi),%eax
  add    %eax,%r8d
L9:
  lea    (%r9,%rcx,1),%eax
  mov    %ecx,%edx
  sub    %ecx,%r9d
  sub    %eax,%r8d
  shr    $0xd,%edx
  xor    %r8d,%edx
  mov    %edx,%eax
  sub    %edx,%r9d
  sub    %edx,%ecx
  shl    $0x8,%eax
  mov    %ecx,%esi
  xor    %r9d,%eax
  mov    %eax,%ecx
  sub    %eax,%esi
  sub    %eax,%edx
  shr    $0xd,%ecx
  xor    %esi,%ecx
  mov    %ecx,%esi
  sub    %ecx,%edx
  sub    %ecx,%eax
  shr    $0xc,%esi
  xor    %edx,%esi
  sub    %esi,%eax
  sub    %esi,%ecx
  mov    %eax,%edx
  mov    %esi,%eax
  shl    $0x10,%eax
  xor    %edx,%eax
  mov    %eax,%edx
  sub    %eax,%ecx
  sub    %eax,%esi
  shr    $0x5,%edx
  xor    %ecx,%edx
  mov    %edx,%ecx
  sub    %edx,%esi
  sub    %edx,%eax
  shr    $0x3,%ecx
  xor    %ecx,%esi
  mov    %esi,%ecx
  sub    %esi,%eax
  sub    %esi,%edx
  shl    $0xa,%ecx
  xor    %ecx,%eax
  sub    %eax,%edx
  shr    $0xf,%eax
  xor    %edx,%eax
  ret
```

assistant: ```c
unsigned int BOB2(const unsigned char *str, unsigned int len) {
  unsigned int a, b, c;
  unsigned int initval = 31;
  a = b = 0x9e3779b9;
  c = initval;
  while (len >= 12) {
    a += (str[0] + ((unsigned int)str[1] << 8) + ((unsigned int)str[2] << 16) + ((unsigned int)str[3] << 24));
    b += (str[4] + ((unsigned int)str[5] << 8) + ((unsigned int)str[6] << 16) + ((unsigned int)str[7] << 24));
    c += (str[8] + ((unsigned int)str[9] << 8) + ((unsigned int)str[10] << 16) + ((unsigned int)str[11] << 24));
    {
      a -= b;
      a -= c;
      a ^= (c >> 13);
      b -= c;
      b -= a;
      b ^= (a << 8);
      c -= a;
      c -= b;
      c ^= (b >> 13);
      a -= b;
      a -= c;
      a ^= (c >> 12);
      b -= c;
      b -= a;
      b ^= (a << 16);
      c -= a;
      c -= b;
      c ^= (b >> 5);
      a -= b;
      a -= c;
      a ^= (c >> 3);
      b -= c;
      b -= a;
      b ^= (a << 10);
      c -= a;
      c -= b;
      c ^= (b >> 15);
    };
    str += 12;
    len -= 12;
  }
  c += len;
  switch (len) {
  case 11:
    c += ((unsigned int)str[10] << 24);
  case 10:
    c += ((unsigned int)str[9] << 16);
  case 9:
    c += ((unsigned int)str[8] << 8);
  case 8:
    b += ((unsigned int)str[7] << 24);
  case 7:
    b += ((unsigned int)str[6] << 16);
  case 6:
    b += ((unsigned int)str[5] << 8);
  case 5:
    b += str[4];
  case 4:
    a += ((unsigned int)str[3] << 24);
  case 3:
    a += ((unsigned int)str[2] << 16);
  case 2:
    a += ((unsigned int)str[1] << 8);
  case 1:
    a += str[0];
  }
  {
    a -= b;
    a -= c;
    a ^= (c >> 13);
    b -= c;
    b -= a;
    b ^= (a << 8);
    c -= a;
    c -= b;
    c ^= (b >> 13);
    a -= b;
    a -= c;
    a ^= (c >> 12);
    b -= c;
    b -= a;
    b ^= (a << 16);
    c -= a;
    c -= b;
    c ^= (b >> 5);
    a -= b;
    a -= c;
    a ^= (c >> 3);
    b -= c;
    b -= a;
    b ^= (a << 10);
    c -= a;
    c -= b;
    c ^= (b >> 15);
  };
  return c;
}
```