boolean shouldDiscardInvariant(Invariant invariant) {
    // System.out.println("OnlyConstantVariablesFilter: " + invariant.format());
    if (IsEqualityComparison.it.accept(invariant)) {
      return false;
    }
    if (invariant instanceof OneOf) {
      return false;
    }
    if (invariant instanceof Implication) {
      Implication impl = (Implication) invariant;
      // jhp 11/04/03, comment out if below.  It seems to never make sense
      // to look at constant variables for the implication itself since
      // the implication is in a PptSlice0 (which will always fail the test
      // below
      // if (impl.predicate().isGuardingPredicate)
      // only consider the consequent
      invariant = impl.consequent();
    }

    VarInfo[] vis = invariant.ppt.var_infos;
    for (int i = 0; i < vis.length; i++) {
      if (!isConstant(vis[i])) {
        // System.out.println("In " + invariant.format() + ": non-constant " + vis[i].name);
        return false;
      }
    }
    return true;
  }
Esempio n. 2
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  /**
   * Extract consequents from a implications at a single program point. It only searches for top
   * level Program points because Implications are produced only at those points.
   */
  public static void extract_consequent_maybe(PptTopLevel ppt, PptMap all_ppts) {
    ppt.simplify_variable_names();

    List<Invariant> invs = new ArrayList<Invariant>();
    if (invs.size() > 0) {
      String pptname = cleanup_pptname(ppt.name());
      for (Invariant maybe_as_inv : invs) {
        Implication maybe = (Implication) maybe_as_inv;

        // don't print redundant invariants.
        if (Daikon.suppress_redundant_invariants_with_simplify
            && maybe.ppt.parent.redundant_invs.contains(maybe)) {
          continue;
        }

        // don't print out invariants with min(), max(), or sum() variables
        boolean mms = false;
        VarInfo[] varbls = maybe.ppt.var_infos;
        for (int v = 0; !mms && v < varbls.length; v++) {
          mms |= varbls[v].isDerivedSequenceMinMaxSum();
        }
        if (mms) {
          continue;
        }

        if (maybe.ppt.parent.ppt_name.isExitPoint()) {
          for (int i = 0; i < maybe.ppt.var_infos.length; i++) {
            VarInfo vi = maybe.ppt.var_infos[i];
            if (vi.isDerivedParam()) {
              continue;
            }
          }
        }

        Invariant consequent = maybe.consequent();
        Invariant predicate = maybe.predicate();
        Invariant inv, cluster_inv;
        boolean cons_uses_cluster = false, pred_uses_cluster = false;
        // extract the consequent (predicate) if the predicate
        // (consequent) uses the variable "cluster".  Ignore if they
        // both depend on "cluster"
        if (consequent.usesVarDerived("cluster")) cons_uses_cluster = true;
        if (predicate.usesVarDerived("cluster")) pred_uses_cluster = true;

        if (!(pred_uses_cluster ^ cons_uses_cluster)) {
          continue;
        } else if (pred_uses_cluster) {
          inv = consequent;
          cluster_inv = predicate;
        } else {
          inv = predicate;
          cluster_inv = consequent;
        }

        if (!inv.isInteresting()) {
          continue;
        }

        if (!inv.isWorthPrinting()) {
          continue;
        }

        if (contains_constant_non_012(inv)) {
          continue;
        }

        // filter out unwanted invariants

        // 1) Invariants involving sequences
        if (inv instanceof daikon.inv.binary.twoSequence.TwoSequence
            || inv instanceof daikon.inv.binary.sequenceScalar.SequenceScalar
            || inv instanceof daikon.inv.binary.sequenceString.SequenceString
            || inv instanceof daikon.inv.unary.sequence.SingleSequence
            || inv instanceof daikon.inv.unary.stringsequence.SingleStringSequence) {
          continue;
        }

        if (inv instanceof daikon.inv.ternary.threeScalar.LinearTernary
            || inv instanceof daikon.inv.binary.twoScalar.LinearBinary) {
          continue;
        }

        String inv_string = inv.format_using(OutputFormat.JAVA);
        if (orig_pattern.matcher(inv_string).find()
            || dot_class_pattern.matcher(inv_string).find()) {
          continue;
        }
        String fake_inv_string = simplify_inequalities(inv_string);
        HashedConsequent real = new HashedConsequent(inv, null);
        if (!fake_inv_string.equals(inv_string)) {
          // For instance, inv_string is "x != y", fake_inv_string is "x == y"
          HashedConsequent fake = new HashedConsequent(inv, inv_string);
          boolean added =
              store_invariant(
                  cluster_inv.format_using(OutputFormat.JAVA), fake_inv_string, fake, pptname);
          if (!added) {
            // We couldn't add "x == y", (when we're "x != y") because
            // it already exists; so don't add "x == y" either.
            continue;
          }
        }
        store_invariant(cluster_inv.format_using(OutputFormat.JAVA), inv_string, real, pptname);
      }
    }
  }