user: 请将这段汇编代码片段转换成等效的C代码：

```asm
<flip_F3>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x30,%rsp
  mov    %rdi,-0x28(%rbp)
  mov    %rsi,-0x30(%rbp)
  mov    -0x28(%rbp),%rax
  shl    $0x9,%rax
  and    -0x30(%rbp),%rax
  movabs $0x200000000,%rdx
  and    %rdx,%rax
  mov    %rax,-0x20(%rbp)
  mov    -0x28(%rbp),%rax
  add    %rax,%rax
  and    -0x30(%rbp),%rax
  movabs $0x20000000000,%rdx
  and    %rdx,%rax
  or     %rax,-0x20(%rbp)
  mov    -0x28(%rbp),%rax
  shr    $0x7,%rax
  and    -0x30(%rbp),%rax
  movabs $0x2000000000000,%rdx
  and    %rdx,%rax
  or     %rax,-0x20(%rbp)
  mov    -0x28(%rbp),%rax
  shr    $0x8,%rax
  and    -0x30(%rbp),%rax
  movabs $0x4000000000000,%rdx
  and    %rdx,%rax
  or     %rax,-0x20(%rbp)
  mov    -0x28(%rbp),%rax
  shr    $0x9,%rax
  and    -0x30(%rbp),%rax
  movabs $0x8000000000000,%rdx
  and    %rdx,%rax
  or     %rax,-0x20(%rbp)
  mov    -0x28(%rbp),%rax
  and    $0x4040404,%eax
  mov    %rax,-0x18(%rbp)
  movabs $0x404040400,%rax
  and    -0x30(%rbp),%rax
  movabs $0x3fbfbfbf800,%rdx
  or     %rdx,%rax
  mov    %rax,-0x10(%rbp)
  mov    -0x18(%rbp),%rax
  shl    $0x8,%rax
  mov    %rax,%rdx
  mov    -0x10(%rbp),%rax
  add    %rax,%rdx
  movabs $0x40000000000,%rax
  and    %rdx,%rax
  mov    %rax,-0x8(%rbp)
  cmpq   $0x0,-0x8(%rbp)
  je     L21
  mov    -0x18(%rbp),%rax
  mov    %rax,%rdi
  call   <last_bit@plt>
  mov    $0x2,%edx
  mov    %eax,%ecx
  shl    %cl,%rdx
  mov    %rdx,%rcx
  movabs $0x40000000000,%rax
  sub    %rcx,%rax
  mov    %rax,%rdx
  movabs $0x404040400,%rax
  and    %rdx,%rax
  or     %rax,-0x20(%rbp)
L21:
  mov    -0x28(%rbp),%rax
  and    $0x10204080,%eax
  mov    %rax,-0x18(%rbp)
  movabs $0x810204000,%rax
  and    -0x30(%rbp),%rax
  movabs $0x3f7efdf8000,%rdx
  or     %rdx,%rax
  mov    %rax,-0x10(%rbp)
  mov    -0x18(%rbp),%rax
  shl    $0x7,%rax
  mov    %rax,%rdx
  mov    -0x10(%rbp),%rax
  add    %rax,%rdx
  movabs $0x40000000000,%rax
  and    %rdx,%rax
  mov    %rax,-0x8(%rbp)
  cmpq   $0x0,-0x8(%rbp)
  je     L13
  mov    -0x18(%rbp),%rax
  mov    %rax,%rdi
  call   <last_bit@plt>
  mov    $0x2,%edx
  mov    %eax,%ecx
  shl    %cl,%rdx
  mov    %rdx,%rcx
  movabs $0x40000000000,%rax
  sub    %rcx,%rax
  mov    %rax,%rdx
  movabs $0x810204000,%rax
  and    %rdx,%rax
  or     %rax,-0x20(%rbp)
L13:
  movabs $0xf00000000000,%rax
  and    -0x28(%rbp),%rax
  mov    %rax,-0x18(%rbp)
  movabs $0x80000000000,%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  and    -0x18(%rbp),%rax
  mov    %rax,-0x8(%rbp)
  cmpq   $0x0,-0x8(%rbp)
  je     L20
  mov    -0x8(%rbp),%rax
  lea    -0x1(%rax),%rdx
  movabs $0xf80000000000,%rax
  and    %rdx,%rax
  or     %rax,-0x20(%rbp)
L20:
  mov    -0x20(%rbp),%rax
  leave
  ret
```

assistant: ```c
unsigned long long flip_F3(const unsigned long long discs_player, const unsigned long long discs_opponent) {
  unsigned long long my_discs, opp_discs, r;
  unsigned long long flipped = (discs_opponent & 0X0000000200000000ULL) & (discs_player << 9);
  flipped |= (discs_opponent & 0X0000020000000000ULL) & (discs_player << 1);
  flipped |= (discs_opponent & 0X0002000000000000ULL) & (discs_player >> 7);
  flipped |= (discs_opponent & 0X0004000000000000ULL) & (discs_player >> 8);
  flipped |= (discs_opponent & 0X0008000000000000ULL) & (discs_player >> 9);
  my_discs = discs_player & 0X0000000004040404ULL;
  opp_discs = (discs_opponent & 0X0000000404040400ULL) | 0X000003FBFBFBF800ULL;
  r = ((my_discs << 8) + opp_discs) & 0X0000040000000000ULL;
  if (r != 0) {
    flipped |= (0X0000040000000000ULL - (0X2ULL << last_bit(my_discs))) & 0X0000000404040400ULL;
  }
  my_discs = discs_player & 0X0000000010204080ULL;
  opp_discs = (discs_opponent & 0X0000000810204000ULL) | 0X000003F7EFDF8000ULL;
  r = ((my_discs << 7) + opp_discs) & 0X0000040000000000ULL;
  if (r != 0) {
    flipped |= (0X0000040000000000ULL - (0X2ULL << last_bit(my_discs))) & 0X0000000810204000ULL;
  }
  my_discs = discs_player & 0X0000F00000000000ULL;
  r = (discs_opponent + 0X0000080000000000ULL) & my_discs;
  if (r != 0) {
    flipped |= (r - 1) & 0X0000F80000000000ULL;
  }
  return flipped;
}
```