user: 下面的汇编指令对应的C源代码是什么：

```asm
<nj_modify_branch_matrix>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %edi,-0x24(%rbp)
  mov    %esi,-0x28(%rbp)
  mov    %edx,-0x2c(%rbp)
  mov    %ecx,-0x30(%rbp)
  mov    %r8,-0x38(%rbp)
  mov    -0x38(%rbp),%rax
  mov    (%rax),%rax
  mov    %rax,-0x10(%rbp)
  movl   $0xffffffff,-0x18(%rbp)
  mov    -0x24(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L30
  mov    -0x28(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L30
  mov    $0xffffffff,%eax
  jmp    L95
L30:
  mov    -0x28(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L37
  movl   $0x1,-0x1c(%rbp)
  jmp    L101
L25:
  mov    -0x1c(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rax
  mov    %rax,-0x8(%rbp)
  mov    -0x28(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L106
  mov    -0x28(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,-0x14(%rbp)
  mov    -0x24(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  cmp    %eax,-0x14(%rbp)
  jne    L65
  mov    -0x2c(%rbp),%edx
  mov    -0x14(%rbp),%eax
  add    %edx,%eax
  cltq
  lea    -0x1(%rax),%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2,%al
  jne    L65
  mov    -0x1c(%rbp),%eax
  mov    %eax,-0x18(%rbp)
L65:
  mov    -0x24(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L81
  mov    -0x2c(%rbp),%edx
  mov    -0x14(%rbp),%eax
  add    %edx,%eax
  cltq
  lea    -0x1(%rax),%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%edx
  sub    $0x1,%edx
  mov    %dl,(%rax)
  jmp    L6
L81:
  mov    -0x24(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  mov    -0x14(%rbp),%edx
  mov    %dl,(%rax)
L6:
  mov    -0x28(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movb   $0x0,(%rax)
L106:
  addl   $0x1,-0x1c(%rbp)
L101:
  mov    -0x1c(%rbp),%eax
  cmp    -0x30(%rbp),%eax
  jl     L25
  mov    -0x24(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movb   $0x1,(%rax)
L37:
  mov    -0x18(%rbp),%eax
L95:
  pop    %rbp
  ret
```

assistant: ```c
int nj_modify_branch_matrix(int mi, int mj, int n, int m, char **branch_matrix) {
  int i, ret_val;
  char *array, *first;
  first = branch_matrix[0];
  ret_val = -1;
  if (first[mi] == 0 && first[mj] == 0)
    return -1;
  if (first[mj]) {
    for (i = 1; i < m; ++i) {
      array = branch_matrix[i];
      if (array[mj]) {
        int tmp = array[mj];
        if (array[mi] == tmp && array[n + tmp - 1] == 2)
          ret_val = i;
        if (first[mi])
          --array[n + tmp - 1];
        else
          array[mi] = tmp;
        array[mj] = 0;
      }
    }
    first[mi] = 1;
  }
  return ret_val;
}
```