Function mi_segment_commitx

3rd/mimalloc-2.0.9/src/segment.c:463–500

static bool mi_segment_commitx(mi_segment_t* segment, bool commit, uint8_t* p, size_t size, mi_stats_t* stats) {    
  mi_assert_internal(mi_commit_mask_all_set(&segment->commit_mask, &segment->decommit_mask));

  // commit liberal, but decommit conservative
  uint8_t* start = NULL;
  size_t   full_size = 0;
  mi_commit_mask_t mask;
  mi_segment_commit_mask(segment, !commit/*conservative*/, p, size, &start, &full_size, &mask);
  if (mi_commit_mask_is_empty(&mask) || full_size==0) return true;

  if (commit && !mi_commit_mask_all_set(&segment->commit_mask, &mask)) {
    bool is_zero = false;
    mi_commit_mask_t cmask;
    mi_commit_mask_create_intersect(&segment->commit_mask, &mask, &cmask);
    _mi_stat_decrease(&_mi_stats_main.committed, _mi_commit_mask_committed_size(&cmask, MI_SEGMENT_SIZE)); // adjust for overlap
    if (!_mi_os_commit(start,full_size,&is_zero,stats)) return false;    
    mi_commit_mask_set(&segment->commit_mask, &mask);     
  }
  else if (!commit && mi_commit_mask_any_set(&segment->commit_mask, &mask)) {
    mi_assert_internal((void*)start != (void*)segment);
    //mi_assert_internal(mi_commit_mask_all_set(&segment->commit_mask, &mask));

    mi_commit_mask_t cmask;
    mi_commit_mask_create_intersect(&segment->commit_mask, &mask, &cmask);
    _mi_stat_increase(&_mi_stats_main.committed, full_size - _mi_commit_mask_committed_size(&cmask, MI_SEGMENT_SIZE)); // adjust for overlap
    if (segment->allow_decommit) { 
      _mi_os_decommit(start, full_size, stats); // ok if this fails
    } 
    mi_commit_mask_clear(&segment->commit_mask, &mask);
  }
  // increase expiration of reusing part of the delayed decommit
  if (commit && mi_commit_mask_any_set(&segment->decommit_mask, &mask)) {
    segment->decommit_expire = _mi_clock_now() + mi_option_get(mi_option_decommit_delay);
  }
  // always undo delayed decommits
  mi_commit_mask_clear(&segment->decommit_mask, &mask);
  return true;
}

static bool mi_segment_ensure_committed(mi_segment_t* segment, uint8_t* p, size_t size, mi_stats_t* stats) {
  mi_assert_internal(mi_commit_mask_all_set(&segment->commit_mask, &segment->decommit_mask));