user: 请将这段汇编代码片段转换成等效的C代码:

```asm
<predict_4x4_ddl>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %rdi,-0x48(%rbp)
  mov    %esi,-0x4c(%rbp)
  mov    %rdx,-0x58(%rbp)
  mov    %ecx,-0x50(%rbp)
  mov    %r8d,-0x5c(%rbp)
  movl   $0x0,-0x24(%rbp)
  mov    -0x50(%rbp),%eax
  mov    %eax,-0x20(%rbp)
  mov    -0x50(%rbp),%eax
  add    %eax,%eax
  mov    %eax,-0x1c(%rbp)
  mov    -0x20(%rbp),%edx
  mov    -0x1c(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x18(%rbp)
  mov    -0x4c(%rbp),%eax
  neg    %eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0x14(%rbp)
  mov    $0x1,%eax
  sub    -0x4c(%rbp),%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0x10(%rbp)
  mov    $0x2,%eax
  sub    -0x4c(%rbp),%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0xc(%rbp)
  mov    $0x3,%eax
  sub    -0x4c(%rbp),%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0x8(%rbp)
  mov    -0x5c(%rbp),%eax
  and    $0x110,%eax
  cmp    $0x110,%eax
  je     L34
  mov    -0x5c(%rbp),%eax
  and    $0x230,%eax
  cmp    $0x230,%eax
  je     L34
  mov    -0x5c(%rbp),%eax
  and    $0x4,%eax
  test   %eax,%eax
  jne    L2
  mov    -0x5c(%rbp),%eax
  and    $0x30,%eax
  cmp    $0x30,%eax
  jne    L2
L34:
  mov    $0x1,%eax
  jmp    L19
L2:
  mov    $0x0,%eax
L19:
  mov    %eax,-0x4(%rbp)
  cmpl   $0x0,-0x4(%rbp)
  jne    L58
  mov    $0x4,%eax
  sub    -0x4c(%rbp),%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0x34(%rbp)
  mov    $0x5,%eax
  sub    -0x4c(%rbp),%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0x30(%rbp)
  mov    $0x6,%eax
  sub    -0x4c(%rbp),%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0x2c(%rbp)
  mov    $0x7,%eax
  sub    -0x4c(%rbp),%eax
  mov    %eax,%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,-0x28(%rbp)
  jmp    L24
L58:
  mov    -0x8(%rbp),%eax
  mov    %eax,-0x28(%rbp)
  mov    -0x28(%rbp),%eax
  mov    %eax,-0x2c(%rbp)
  mov    -0x2c(%rbp),%eax
  mov    %eax,-0x30(%rbp)
  mov    -0x30(%rbp),%eax
  mov    %eax,-0x34(%rbp)
L24:
  mov    -0x10(%rbp),%eax
  lea    (%rax,%rax,1),%edx
  mov    -0x14(%rbp),%eax
  add    %eax,%edx
  mov    -0xc(%rbp),%eax
  add    %edx,%eax
  add    $0x2,%eax
  sar    $0x2,%eax
  mov    %eax,%ecx
  mov    -0x24(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x58(%rbp),%rax
  add    %rdx,%rax
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0xc(%rbp),%eax
  lea    (%rax,%rax,1),%edx
  mov    -0x10(%rbp),%eax
  add    %eax,%edx
  mov    -0x8(%rbp),%eax
  add    %edx,%eax
  add    $0x2,%eax
  sar    $0x2,%eax
  mov    %eax,%ecx
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x58(%rbp),%rax
  add    %rdx,%rax
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%edx
  movslq %edx,%rdx
  lea    0x1(%rdx),%rcx
  mov    -0x58(%rbp),%rdx
  add    %rcx,%rdx
  movzbl (%rax),%eax
  mov    %al,(%rdx)
  mov    -0x8(%rbp),%eax
  lea    (%rax,%rax,1),%edx
  mov    -0xc(%rbp),%eax
  add    %eax,%edx
  mov    -0x34(%rbp),%eax
  add    %edx,%eax
  add    $0x2,%eax
  sar    $0x2,%eax
  mov    %eax,%ecx
  mov    -0x1c(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x58(%rbp),%rax
  add    %rax,%rdx
  mov    %ecx,%eax
  mov    %al,(%rdx)
  mov    -0x20(%rbp),%eax
  cltq
  lea    0x1(%rax),%rcx
  mov    -0x58(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rdx),%edx
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%edx
  movslq %edx,%rdx
  lea    0x2(%rdx),%rcx
  mov    -0x58(%rbp),%rdx
  add    %rcx,%rdx
  movzbl (%rax),%eax
  mov    %al,(%rdx)
  mov    -0x34(%rbp),%eax
  lea    (%rax,%rax,1),%edx
  mov    -0x8(%rbp),%eax
  add    %eax,%edx
  mov    -0x30(%rbp),%eax
  add    %edx,%eax
  add    $0x2,%eax
  sar    $0x2,%eax
  mov    %eax,%ecx
  mov    -0x18(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x58(%rbp),%rax
  add    %rdx,%rax
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x1c(%rbp),%edx
  movslq %edx,%rdx
  lea    0x1(%rdx),%rcx
  mov    -0x58(%rbp),%rdx
  add    %rcx,%rdx
  movzbl (%rax),%eax
  mov    %al,(%rdx)
  mov    -0x20(%rbp),%eax
  cltq
  lea    0x2(%rax),%rcx
  mov    -0x58(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rdx),%edx
  mov    %dl,(%rax)
  mov    -0x24(%rbp),%edx
  movslq %edx,%rdx
  lea    0x3(%rdx),%rcx
  mov    -0x58(%rbp),%rdx
  add    %rcx,%rdx
  movzbl (%rax),%eax
  mov    %al,(%rdx)
  mov    -0x30(%rbp),%eax
  lea    (%rax,%rax,1),%edx
  mov    -0x34(%rbp),%eax
  add    %eax,%edx
  mov    -0x2c(%rbp),%eax
  add    %edx,%eax
  add    $0x2,%eax
  sar    $0x2,%eax
  mov    %eax,%ecx
  mov    -0x18(%rbp),%eax
  cltq
  lea    0x1(%rax),%rdx
  mov    -0x58(%rbp),%rax
  add    %rax,%rdx
  mov    %ecx,%eax
  mov    %al,(%rdx)
  mov    -0x1c(%rbp),%eax
  cltq
  lea    0x2(%rax),%rcx
  mov    -0x58(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rdx),%edx
  mov    %dl,(%rax)
  mov    -0x20(%rbp),%edx
  movslq %edx,%rdx
  lea    0x3(%rdx),%rcx
  mov    -0x58(%rbp),%rdx
  add    %rcx,%rdx
  movzbl (%rax),%eax
  mov    %al,(%rdx)
  mov    -0x2c(%rbp),%eax
  lea    (%rax,%rax,1),%edx
  mov    -0x30(%rbp),%eax
  add    %eax,%edx
  mov    -0x28(%rbp),%eax
  add    %edx,%eax
  add    $0x2,%eax
  sar    $0x2,%eax
  mov    %eax,%edx
  mov    -0x18(%rbp),%eax
  cltq
  lea    0x2(%rax),%rcx
  mov    -0x58(%rbp),%rax
  add    %rcx,%rax
  mov    %dl,(%rax)
  mov    -0x1c(%rbp),%edx
  movslq %edx,%rdx
  lea    0x3(%rdx),%rcx
  mov    -0x58(%rbp),%rdx
  add    %rcx,%rdx
  movzbl (%rax),%eax
  mov    %al,(%rdx)
  mov    -0x28(%rbp),%edx
  mov    %edx,%eax
  add    %eax,%eax
  add    %eax,%edx
  mov    -0x2c(%rbp),%eax
  add    %edx,%eax
  add    $0x2,%eax
  sar    $0x2,%eax
  mov    %eax,%edx
  mov    -0x18(%rbp),%eax
  cltq
  lea    0x3(%rax),%rcx
  mov    -0x58(%rbp),%rax
  add    %rcx,%rax
  mov    %dl,(%rax)
  nop
  pop    %rbp
  ret
```

assistant: ```c
void predict_4x4_ddl(unsigned char *src, unsigned int src_stride, unsigned char *dst, unsigned int dst_stride, int neighbour) {
  const int dst_row_0 = 0;
  const int dst_row_1 = dst_stride;
  const int dst_row_2 = dst_stride * 2;
  const int dst_row_3 = dst_row_1 + dst_row_2;
  const int t0 = src[0 - 1 * src_stride];
  const int t1 = src[1 - 1 * src_stride];
  const int t2 = src[2 - 1 * src_stride];
  const int t3 = src[3 - 1 * src_stride];
  int t4, t5, t6, t7;
  const int emulate = ((neighbour & 0x110) == 0x110) || ((neighbour & 0x230) == 0x230) || (((neighbour & 4) != 4) && ((neighbour & 0x030) == 0x030));
  if (!emulate) {
    t4 = src[4 - 1 * src_stride];
    t5 = src[5 - 1 * src_stride];
    t6 = src[6 - 1 * src_stride];
    t7 = src[7 - 1 * src_stride];
  } else {
    t4 = t5 = t6 = t7 = t3;
  }
  dst[dst_row_0 + 0] = (t0 + 2 * t1 + t2 + 2) >> 2;
  dst[dst_row_0 + 1] = dst[dst_row_1 + 0] = (t1 + 2 * t2 + t3 + 2) >> 2;
  dst[dst_row_0 + 2] = dst[dst_row_1 + 1] = dst[dst_row_2 + 0] = (t2 + 2 * t3 + t4 + 2) >> 2;
  dst[dst_row_0 + 3] = dst[dst_row_1 + 2] = dst[dst_row_2 + 1] = dst[dst_row_3 + 0] = (t3 + 2 * t4 + t5 + 2) >> 2;
  dst[dst_row_1 + 3] = dst[dst_row_2 + 2] = dst[dst_row_3 + 1] = (t4 + 2 * t5 + t6 + 2) >> 2;
  dst[dst_row_2 + 3] = dst[dst_row_3 + 2] = (t5 + 2 * t6 + t7 + 2) >> 2;
  dst[dst_row_3 + 3] = (t6 + 3 * t7 + 2) >> 2;
}
```