Function is_map

deps/v8/tools/windbg.js:374–387

(addr)

    Exploring objects
-----------------------------------------------------------------------------*/
function is_map(addr) {
  let address = int(addr);
  if (!Number.isSafeInteger(address) || address % 2 == 0) return false;

  // the first field in all objects, including maps, is a map pointer, but for
  // maps the pointer is always the same - the meta map that points to itself.
  const map_addr = int(poim(address - 1));
  if (!Number.isSafeInteger(map_addr)) return false;

  const map_map_addr = int(poim(map_addr - 1));
  if (!Number.isSafeInteger(map_map_addr)) return false;

  return (map_addr === map_map_addr);
}

function is_likely_object(addr) {
  let address = int(addr);