user: Converte this assembly snippet into its equivalent C code:

```asm
<get_pawn_moves_black>:
  endbr64
  push   %r15
  mov    $0x61,%r15d
  push   %r14
  push   %r13
  push   %r12
  mov    %rdi,%r12
  push   %rbp
  push   %rbx
  mov    %rsi,%rbx
  sub    $0x18,%rsp
  mov    %rdx,0x8(%rsp)
  nopl   0x0(%rax,%rax,1)
L63:
  lea    -0x1(%r15),%eax
  mov    %r15b,0x7(%rsp)
  mov    $0x31,%r14d
  lea    0x1(%r15),%r13d
  mov    %eax,(%rsp)
  jmp    L131
L53:
  add    $0x1,%r14d
  cmp    $0x39,%r14d
  je     L92
L131:
  mov    %r14d,%edx
  mov    %r15d,%esi
  mov    %rbx,%rdi
  call   <get_piece@plt>
  cmp    $0x70,%al
  jne    L53
  cmp    $0x37,%r14d
  je     L112
  cmp    $0x31,%r14b
  je     L53
L163:
  lea    -0x1(%r14),%ebp
  mov    %r15d,%esi
  mov    %rbx,%rdi
  mov    %ebp,%edx
  call   <is_occupied@plt>
  test   %eax,%eax
  je     L129
L6:
  cmp    $0x61,%r15d
  je     L164
  mov    (%rsp),%esi
  mov    %ebp,%edx
  mov    %rbx,%rdi
  call   <is_occupied@plt>
  cmp    $0x1,%eax
  je     L167
L79:
  cmpb   $0x67,0x7(%rsp)
  jg     L53
  nopl   0x0(%rax)
L164:
  mov    %ebp,%edx
  mov    %r13d,%esi
  mov    %rbx,%rdi
  call   <is_occupied@plt>
  cmp    $0x1,%eax
  jne    L53
  push   %rbp
  mov    %r14d,%r9d
  xor    %edx,%edx
  mov    %r12,%rdi
  push   %r13
  mov    0x18(%rsp),%rcx
  mov    %r15d,%r8d
  mov    %rbx,%rsi
  add    $0x1,%r14d
  call   <store_move@plt>
  mov    %rax,%r12
  pop    %rax
  pop    %rdx
  cmp    $0x39,%r14d
  jne    L131
  nopl   0x0(%rax)
L92:
  mov    %r13d,%r15d
  cmp    $0x69,%r13d
  jne    L63
  add    $0x18,%rsp
  mov    %r12,%rax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopw   0x0(%rax,%rax,1)
L129:
  push   %rbp
  mov    %r12,%rdi
  mov    %r15d,%r8d
  mov    %r14d,%r9d
  push   %r15
  mov    0x18(%rsp),%rcx
  xor    %edx,%edx
  mov    %rbx,%rsi
  call   <store_move@plt>
  pop    %rdi
  pop    %r8
  mov    %rax,%r12
  jmp    L6
  cs nopw 0x0(%rax,%rax,1)
L112:
  mov    $0x36,%edx
  mov    %r15d,%esi
  mov    %rbx,%rdi
  call   <is_occupied@plt>
  test   %eax,%eax
  jne    L163
  mov    $0x35,%edx
  mov    %r15d,%esi
  mov    %rbx,%rdi
  call   <is_occupied@plt>
  test   %eax,%eax
  jne    L163
  push   $0x35
  mov    $0x37,%r9d
  mov    %r12,%rdi
  mov    %r15d,%r8d
  push   %r15
  mov    0x18(%rsp),%rcx
  xor    %edx,%edx
  mov    %rbx,%rsi
  call   <store_move@plt>
  pop    %r9
  pop    %r10
  mov    %rax,%r12
  jmp    L163
  nopl   0x0(%rax,%rax,1)
L167:
  push   %rbp
  mov    0x8(%rsp),%eax
  mov    %rbx,%rsi
  mov    %r12,%rdi
  mov    %r14d,%r9d
  mov    %r15d,%r8d
  xor    %edx,%edx
  push   %rax
  mov    0x18(%rsp),%rcx
  call   <store_move@plt>
  pop    %rcx
  pop    %rsi
  mov    %rax,%r12
  jmp    L79
```

assistant: ```c
struct node *get_pawn_moves_black(struct node *currentNode, char *board, struct node *parentNode) {
  char x, y;
  int numMoves = 0;
  for (x = 'a'; x <= 'h'; x++) {
    for (y = '1'; y <= '8'; y++) {
      char p = get_piece(board, x, y);
      if (p == 'p') {
        if ((y == '7') && (is_occupied(board, x, y - 1) == 0) && (is_occupied(board, x, y - 2) == 0)) {
          currentNode = store_move(currentNode, board, 0, parentNode, x, y, x, y - 2);
          numMoves++;
        }
        if ((y > '1') && (is_occupied(board, x, y - 1) == 0)) {
          currentNode = store_move(currentNode, board, 0, parentNode, x, y, x, y - 1);
          numMoves++;
        }
        if ((x > 'a') && (y > '1') && (is_occupied(board, x - 1, y - 1) == 1)) {
          currentNode = store_move(currentNode, board, 0, parentNode, x, y, x - 1, y - 1);
          numMoves++;
        }
        if ((x < 'h') && (y > '1') && (is_occupied(board, x + 1, y - 1) == 1)) {
          currentNode = store_move(currentNode, board, 0, parentNode, x, y, x + 1, y - 1);
          numMoves++;
        }
      }
    }
  }
  return currentNode;
}
```