user: 请将这段汇编代码片段转换成等效的C代码：

```asm
<flip_H5>:
  endbr64
  push   %r12
  lea    0x2000000(%rsi),%r12
  and    %rdi,%r12
  push   %rbp
  mov    %rdi,%rbp
  push   %rbx
  mov    %rsi,%rbx
  and    $0xfc000000,%r12d
  je     L53
  sub    $0x1,%r12
  and    $0xfe000000,%r12d
L53:
  mov    %rbp,%rdi
  mov    %rbx,%rax
  and    $0x408,%edi
  and    $0x20400,%eax
  mov    %rdi,%rdx
  or     $0xfdf800,%rax
  shl    $0x7,%rdx
  add    %rdx,%rax
  test   $0x1000000,%eax
  jne    L61
L20:
  movabs $0x8040200000000,%rcx
  mov    %rbx,%rax
  movabs $0xff7fbfc00000000,%rdx
  and    %rcx,%rax
  or     %rdx,%rax
  movabs $0x200000000,%rdx
  add    %rdx,%rax
  movabs $0x1008040000000000,%rdx
  and    %rbp,%rax
  and    %rdx,%rax
  je     L39
  sub    $0x1,%rax
  and    %rcx,%rax
  or     %rax,%r12
L39:
  mov    %rbp,%rdi
  mov    %rbx,%rax
  and    $0x101,%edi
  and    $0x10100,%eax
  mov    %rdi,%rdx
  or     $0xfefe00,%rax
  shl    $0x8,%rdx
  add    %rdx,%rax
  test   $0x1000000,%eax
  jne    L16
L64:
  movabs $0x1010100000000,%rdx
  movabs $0xfefefe00000000,%rax
  and    %rdx,%rbx
  or     %rax,%rbx
  movabs $0x100000000,%rax
  add    %rax,%rbx
  movabs $0x101010000000000,%rax
  and    %rbp,%rbx
  and    %rax,%rbx
  je     L37
  sub    $0x1,%rbx
  and    %rdx,%rbx
  or     %rbx,%r12
L37:
  mov    %r12,%rax
  pop    %rbx
  pop    %rbp
  pop    %r12
  ret
  nopl   0x0(%rax)
L61:
  call   <last_bit@plt>
  mov    $0xfffffffffffffffe,%rdx
  mov    %eax,%ecx
  shl    %cl,%rdx
  and    $0x20400,%edx
  or     %rdx,%r12
  jmp    L20
  nopw   0x0(%rax,%rax,1)
L16:
  call   <last_bit@plt>
  mov    $0xfffffffffffffffe,%rdx
  mov    %eax,%ecx
  shl    %cl,%rdx
  and    $0x10100,%edx
  or     %rdx,%r12
  jmp    L64
```

assistant: ```c
unsigned long long flip_H5(const unsigned long long discs_player, const unsigned long long discs_opponent) {
  unsigned long long my_discs, opp_discs, r, flipped = 0ULL;
  my_discs = discs_player & 0X00000000FC000000ULL;
  r = (discs_opponent + 0X0000000002000000ULL) & my_discs;
  if (r != 0) {
    flipped |= (r - 1) & 0X00000000FE000000ULL;
  }
  my_discs = discs_player & 0X0000000000000408ULL;
  opp_discs = (discs_opponent & 0X0000000000020400ULL) | 0X0000000000FDF800ULL;
  r = ((my_discs << 7) + opp_discs) & 0X0000000001000000ULL;
  if (r != 0) {
    flipped |= (0X0000000001000000ULL - (0X2ULL << last_bit(my_discs))) & 0X0000000000020400ULL;
  }
  my_discs = discs_player & 0X1008040000000000ULL;
  opp_discs = (discs_opponent & 0X0008040200000000ULL) | 0X0FF7FBFC00000000ULL;
  r = (opp_discs + 0X0000000200000000ULL) & my_discs;
  if (r != 0) {
    flipped |= (r - 1) & 0X0008040200000000ULL;
  }
  my_discs = discs_player & 0X0000000000000101ULL;
  opp_discs = (discs_opponent & 0X0000000000010100ULL) | 0X0000000000FEFE00ULL;
  r = ((my_discs << 8) + opp_discs) & 0X0000000001000000ULL;
  if (r != 0) {
    flipped |= (0X0000000001000000ULL - (0X2ULL << last_bit(my_discs))) & 0X0000000000010100ULL;
  }
  my_discs = discs_player & 0X0101010000000000ULL;
  opp_discs = (discs_opponent & 0X0001010100000000ULL) | 0X00FEFEFE00000000ULL;
  r = (opp_discs + 0X0000000100000000ULL) & my_discs;
  if (r != 0) {
    flipped |= (r - 1) & 0X0001010100000000ULL;
  }
  return flipped;
}
```