Source file intervals_congruences.ml

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(* This file is part of MOPSA, a Modular Open Platform for Static Analysis. *)
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(* Copyright (C) 2017-2019 The MOPSA Project.                               *)
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(** Reduction operator for intervals and congruences. *)

open Mopsa
open Sig.Reduction.Value



module Reduction =
struct

  let name = "universal.numeric.reductions.intervals_congruences"
  let debug fmt = Debug.debug ~channel:name fmt

  module I = Values.Intervals.Integer.Value
  module C = Values.Congruences.Value


  (* Reduce a congruence and an interval *)
  let meet_cgr_itv c i =
    match c, i with
    | Bot.BOT, _ | _, Bot.BOT -> (C.bottom, I.bottom)

    | Bot.Nb a, Bot.Nb b ->
      match CongUtils.IntCong.meet_inter a b with
      | Bot.BOT -> (C.bottom, I.bottom)

      | Bot.Nb (a', b') ->
        let c' = Bot.Nb a'
        and i' = Bot.Nb b' in
        (c', i')

  (* Reduction operator *)
  let reduce (man: 'a value_reduction_man) (v: 'a) : 'a =
    let c = man.get C.id v
    and i = man.get I.id v in

    let c', i' = meet_cgr_itv c i in

    man.set I.id i' v |>
    man.set C.id c'
end


let () =
  register_value_reduction (module Reduction)