another-nonvector comes from here

also-nonvector.c

/* Stores the hash of the next 4 bytes and in a single tree-traversal, the
   hash bucket's binary tree is searched for matches and is re-rooted at the
   current position.
   If less than MAX_TREE_COMP_LENGTH data is available, the hash bucket of the
   current position is searched for matches, but the state of the hash table
   is not changed, since we can not know the final sorting order of the
   current (incomplete) sequence.
   This function must be called with increasing cur_ix positions. */
static BROTLI_INLINE BackwardMatch* FN(StoreAndFindMatches)(
    HashToBinaryTree* self, const uint8_t* const BROTLI_RESTRICT data,
    const size_t cur_ix, const size_t ring_buffer_mask, const size_t max_length,
    const size_t max_backward, size_t* const BROTLI_RESTRICT best_len,
    BackwardMatch* BROTLI_RESTRICT matches) {
  const size_t cur_ix_masked = cur_ix & ring_buffer_mask;
  const size_t max_comp_len =
      BROTLI_MIN(size_t, max_length, MAX_TREE_COMP_LENGTH);
  const BROTLI_BOOL should_reroot_tree =
      TO_BROTLI_BOOL(max_length >= MAX_TREE_COMP_LENGTH);
  const uint32_t key = FN(HashBytes)(&data[cur_ix_masked]);
  uint32_t* forest = FN(Forest)(self);
  size_t prev_ix = self->buckets_[key];
  /* The forest index of the rightmost node of the left subtree of the new
     root, updated as we traverse and re-root the tree of the hash bucket. */
  size_t node_left = FN(LeftChildIndex)(self, cur_ix);
  /* The forest index of the leftmost node of the right subtree of the new
     root, updated as we traverse and re-root the tree of the hash bucket. */
  size_t node_right = FN(RightChildIndex)(self, cur_ix);
  /* The match length of the rightmost node of the left subtree of the new
     root, updated as we traverse and re-root the tree of the hash bucket. */
  size_t best_len_left = 0;
  /* The match length of the leftmost node of the right subtree of the new
     root, updated as we traverse and re-root the tree of the hash bucket. */
  size_t best_len_right = 0;
  size_t depth_remaining;
  if (should_reroot_tree) {
    self->buckets_[key] = (uint32_t)cur_ix;
  }
  for (depth_remaining = MAX_TREE_SEARCH_DEPTH; ; --depth_remaining) {
    const size_t backward = cur_ix - prev_ix;
    const size_t prev_ix_masked = prev_ix & ring_buffer_mask;
    if (backward == 0 || backward > max_backward || depth_remaining == 0) {
      if (should_reroot_tree) {
        forest[node_left] = self->invalid_pos_;
        forest[node_right] = self->invalid_pos_;
      }
      break;
    }
    {
      const size_t cur_len = BROTLI_MIN(size_t, best_len_left, best_len_right);
      size_t len;
      BROTLI_DCHECK(cur_len <= MAX_TREE_COMP_LENGTH);
      len = cur_len +
          FindMatchLengthWithLimit(&data[cur_ix_masked + cur_len],
                                   &data[prev_ix_masked + cur_len],
                                   max_length - cur_len);
      BROTLI_DCHECK(
          0 == memcmp(&data[cur_ix_masked], &data[prev_ix_masked], len));
      if (matches && len > *best_len) {
        *best_len = len;
        InitBackwardMatch(matches++, backward, len);
      }
      if (len >= max_comp_len) {
        if (should_reroot_tree) {
          forest[node_left] = forest[FN(LeftChildIndex)(self, prev_ix)];
          forest[node_right] = forest[FN(RightChildIndex)(self, prev_ix)];
        }
        break;
      }
      if (data[cur_ix_masked + len] > data[prev_ix_masked + len]) {
        best_len_left = len;
        if (should_reroot_tree) {
          forest[node_left] = (uint32_t)prev_ix;
        }
        node_left = FN(RightChildIndex)(self, prev_ix);
        prev_ix = forest[node_left];
      } else {
        best_len_right = len;
        if (should_reroot_tree) {
          forest[node_right] = (uint32_t)prev_ix;
        }
        node_right = FN(LeftChildIndex)(self, prev_ix);
        prev_ix = forest[node_right];
      }
    }
  }
  return matches;
}