user: What is the c source code of the assembly code below?

```asm
<mark_pos>:
  endbr64
  movslq %esi,%rax
  movslq %edx,%r11
  mov    %ecx,%esi
  push   %r13
  mov    (%rdi,%rax,8),%r10
  push   %r12
  mov    %rax,%r8
  mov    %r11,%r9
  push   %rbp
  lea    0x0(,%r11,4),%rcx
  push   %rbx
  test   %esi,%esi
  jle    L205
  lea    -0x1(%rsi),%ebp
  mov    %rdi,%rax
  lea    0x8(%rdi,%rbp,8),%rbx
  nopl   0x0(%rax,%rax,1)
L124:
  mov    (%rax),%rdx
  add    %rcx,%rdx
  mov    (%rdx),%r13d
  test   %r13d,%r13d
  jne    L192
  movl   $0xa,(%rdx)
L192:
  add    $0x8,%rax
  cmp    %rbx,%rax
  jne    L124
  mov    %r10,%rax
  lea    (%r10,%rbp,4),%rbx
  jmp    L215
  xchg   %ax,%ax
L269:
  mov    %rdx,%rax
L215:
  mov    (%rax),%r12d
  test   %r12d,%r12d
  jne    L238
  movl   $0xa,(%rax)
L238:
  lea    0x4(%rax),%rdx
  cmp    %rax,%rbx
  jne    L269
L205:
  cmp    %r9d,%r8d
  mov    %r9d,%eax
  cmovge %r8d,%eax
  cmp    %eax,%esi
  jle    L127
  lea    0x1(%r8),%edx
  mov    %r9d,%r12d
  mov    %rcx,%rbx
  mov    %r10,%rax
  movslq %edx,%rdx
  sub    %r8d,%r12d
  jmp    L25
  nopl   (%rax)
L86:
  mov    (%rdi,%rdx,8),%rax
  add    $0x1,%rdx
L25:
  add    %rbx,%rax
  mov    (%rax),%ebp
  test   %ebp,%ebp
  jne    L93
  movl   $0xa,(%rax)
L93:
  lea    (%r12,%rdx,1),%eax
  add    $0x4,%rbx
  cmp    %edx,%eax
  cmovl  %edx,%eax
  cmp    %esi,%eax
  jl     L86
L127:
  mov    %r8d,%ebp
  mov    %r9d,%r13d
  mov    %r8d,%eax
  not    %ebp
  not    %r13d
  shr    $0x1f,%ebp
  shr    $0x1f,%r13d
  or     %r9d,%eax
  js     L151
  lea    -0x1(%r8),%eax
  mov    %r9d,%r12d
  mov    %rcx,%rbx
  mov    %r10,%rdx
  cltq
  sub    %r8d,%r12d
  jmp    L102
  cs nopw 0x0(%rax,%rax,1)
L231:
  mov    (%rdi,%rax,8),%rdx
  sub    $0x1,%rax
L102:
  add    %rbx,%rdx
  cmpl   $0x0,(%rdx)
  jne    L10
  movl   $0xa,(%rdx)
L10:
  mov    %r12d,%edx
  sub    $0x4,%rbx
  add    %eax,%edx
  js     L151
  test   %eax,%eax
  jns    L231
L151:
  cmp    %r8d,%esi
  jle    L17
  test   %r13b,%r13b
  je     L17
  lea    0x1(%r8),%eax
  mov    %rcx,%r12
  lea    (%r9,%r8,1),%ebx
  mov    %r10,%rdx
  cltq
  jmp    L176
  nopl   0x0(%rax)
L111:
  mov    (%rdi,%rax,8),%rdx
  add    $0x1,%rax
L176:
  add    %r12,%rdx
  mov    (%rdx),%r13d
  test   %r13d,%r13d
  jne    L244
  movl   $0xa,(%rdx)
L244:
  sub    $0x4,%r12
  cmp    %eax,%ebx
  js     L17
  cmp    %eax,%esi
  jg     L111
L17:
  cmp    %r9d,%esi
  jle    L125
  test   %bpl,%bpl
  je     L125
  lea    -0x1(%r8),%eax
  mov    %r10,%rdx
  lea    (%r9,%r8,1),%ebx
  cltq
  jmp    L149
  cs nopw 0x0(%rax,%rax,1)
L40:
  mov    (%rdi,%rax,8),%rdx
  sub    $0x1,%rax
L149:
  add    %rcx,%rdx
  mov    (%rdx),%r8d
  test   %r8d,%r8d
  jne    L225
  movl   $0xa,(%rdx)
L225:
  mov    %ebx,%edx
  add    $0x4,%rcx
  sub    %eax,%edx
  cmp    %esi,%edx
  jge    L125
  test   %eax,%eax
  jns    L40
L125:
  movl   $0x14,(%r10,%r11,4)
  xor    %eax,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  ret
```

assistant: ```c
int mark_pos(int **board, int x, int y, int q) {
  int i = 0, j = 0;
  int flag = 0;
  for (i = 0; i < q; i++) {
    j = y;
    if (board[i][j] == 0) {
      board[i][j] = 10;
    }
  }
  for (j = 0; j < q; j++) {
    i = x;
    if (board[i][j] == 0) {
      board[i][j] = 10;
    }
  }
  for (i = x, j = y; i < q && j < q; i++, j++) {
    if (board[i][j] == 0) {
      board[i][j] = 10;
    }
  }
  for (i = x, j = y; i >= 0 && j >= 0; i--, j--) {
    if (board[i][j] == 0) {
      board[i][j] = 10;
    }
  }
  for (i = x, j = y; i < q && j >= 0; i++, j--) {
    if (board[i][j] == 0) {
      board[i][j] = 10;
    }
  }
  for (i = x, j = y; i >= 0 && j < q; i--, j++) {
    if (board[i][j] == 0) {
      board[i][j] = 10;
    }
  }
  board[x][y] = 20;
  return 0;
}
```