Source file skip_list_costs.ml

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module S = Saturation_repr

(* Inferred from model model_next in file skip_list_benchmarks.ml *)
(* fun size -> (19.813850951 * (log2 (1 + size))) *)
let model_next ~length =
  let open S.Syntax in
  let length = S.safe_z length in
  S.safe_int 20 * log2 (S.safe_int 1 + length)

(* Inferred from model proto/alpha/skip_list/hash_cell in file
   skip_list_benchmarks.ml *)
(* fun size -> (242.202299543 + (56.9693504823 * size)) *)
let model_hash_cell backpointers_count =
  let open S.Syntax in
  S.safe_int 250 + (S.safe_int 57 * backpointers_count)

let model_hash_cell_computed_backpointers_count ~index =
  model_hash_cell (S.Syntax.log2 (S.safe_z index))

let model_hash_cell ~backpointers_count =
  model_hash_cell (S.safe_int backpointers_count)