Function mi_bitmap_init

system/lib/mimalloc/src/bitmap.c:1034–1043

initialize a bitmap to all unset; avoid a mem_zero if `already_zero` is true returns the size of the bitmap

// initialize a bitmap to all unset; avoid a mem_zero if `already_zero` is true
// returns the size of the bitmap
size_t mi_bitmap_init(mi_bitmap_t* bitmap, size_t bit_count, bool already_zero) {
  size_t chunk_count;
  const size_t size = mi_bitmap_size(bit_count, &chunk_count);
  if (!already_zero) {
    _mi_memzero_aligned(bitmap, size);
  }
  mi_atomic_store_release(&bitmap->chunk_count, chunk_count);
  mi_assert_internal(mi_atomic_load_relaxed(&bitmap->chunk_count) <= MI_BITMAP_MAX_CHUNK_COUNT);
  return size;
}


// Set a sequence of `n` bits in the bitmap (and can cross chunks). Not atomic so only use if local to a thread.