/**
     * process the sample by checking it against each existing invariant and issuing an error if any
     * invariant is falsified or weakened.
     */
    public void process_sample(PptMap all_ppts, PptTopLevel ppt, ValueTuple vt, Integer nonce) {

      this.all_ppts = all_ppts;

      debug.fine("processing sample from: " + ppt.name);

      // Add orig and derived variables
      FileIO.add_orig_variables(ppt, vt.vals, vt.mods, nonce);
      FileIO.add_derived_variables(ppt, vt.vals, vt.mods);

      // Intern the sample
      vt = new ValueTuple(vt.vals, vt.mods);

      // If this is an enter point, just remember it for later
      if (ppt.ppt_name.isEnterPoint()) {
        Assert.assertTrue(nonce != null);
        if (dir_file != null) {
          // Yoav: I had to do a hack to handle the case that several dtrace files are concatenated
          // together,
          // and Sung's dtrace files have unterminated calls, and when concatenating two files you
          // can have the same nonce.
          // So I have to remove the nonce found from the call_map
          call_map.remove(nonce);
        } else Assert.assertTrue(call_map.get(nonce) == null);
        call_map.put(nonce, new EnterCall(ppt, vt));
        debug.fine("Skipping enter sample");
        return;
      }

      // If this is an exit point, process the saved enter point
      if (ppt.ppt_name.isExitPoint()) {
        Assert.assertTrue(nonce != null);
        EnterCall ec = call_map.get(nonce);
        if (ec != null) {
          call_map.remove(nonce);
          debug.fine("Processing enter sample from " + ec.ppt.name);
          add(ec.ppt, ec.vt);
        } else { // didn't find the enter
          if (!quiet)
            System.out.printf("couldn't find enter for nonce %d at ppt %s\n", nonce, ppt.name());
          return;
        }
      }

      add(ppt, vt);
    }
  // Store the invariant for later printing. Ignore duplicate
  // invariants at the same program point.
  private static boolean store_invariant(
      String predicate, String index, HashedConsequent consequent, String pptname) {
    if (!pptname_to_conditions.containsKey(pptname)) {
      pptname_to_conditions.put(pptname, new HashMap<String, Map<String, HashedConsequent>>());
    }

    Map<String, Map<String, HashedConsequent>> cluster_to_conditions =
        pptname_to_conditions.get(pptname);
    if (!cluster_to_conditions.containsKey(predicate)) {
      cluster_to_conditions.put(predicate, new HashMap<String, HashedConsequent>());
    }

    Map<String, HashedConsequent> conditions = cluster_to_conditions.get(predicate);
    if (conditions.containsKey(index)) {
      HashedConsequent old = conditions.get(index);
      if (old.fakeFor != null && consequent.fakeFor == null) {
        // We already saw (say) "x != y", but we're "x == y", so replace it.
        conditions.remove(index);
        conditions.remove(old.fakeFor);
        conditions.put(index, consequent);
        return true;
      }
      return false;
    } else {
      conditions.put(index, consequent);
      return true;
    }
  }
  public static void extract_consequent(PptMap ppts) {
    // Retrieve Ppt objects in sorted order.
    // Use a custom comparator for a specific ordering
    Comparator<PptTopLevel> comparator = new Ppt.NameComparator();
    TreeSet<PptTopLevel> ppts_sorted = new TreeSet<PptTopLevel>(comparator);
    ppts_sorted.addAll(ppts.asCollection());

    for (PptTopLevel ppt : ppts_sorted) {
      extract_consequent_maybe(ppt, ppts);
    }

    PrintWriter pw = new PrintWriter(System.out, true);

    // All conditions at a program point.  A TreeSet to enable
    // deterministic output.
    TreeSet<String> allConds = new TreeSet<String>();
    for (String pptname : pptname_to_conditions.keySet()) {
      Map<String, Map<String, HashedConsequent>> cluster_to_conditions =
          pptname_to_conditions.get(pptname);
      for (Map.Entry</*@KeyFor("cluster_to_conditions")*/ String, Map<String, HashedConsequent>>
          entry : cluster_to_conditions.entrySet()) {
        String predicate = entry.getKey();
        Map<String, HashedConsequent> conditions = entry.getValue();
        StringBuffer conjunctionJava = new StringBuffer();
        StringBuffer conjunctionDaikon = new StringBuffer();
        StringBuffer conjunctionESC = new StringBuffer();
        StringBuffer conjunctionSimplify = new StringBuffer("(AND ");
        int count = 0;
        for (Map.Entry</*@KeyFor("conditions")*/ String, HashedConsequent> entry2 :
            conditions.entrySet()) {
          count++;
          String condIndex = entry2.getKey();
          HashedConsequent cond = entry2.getValue();
          if (cond.fakeFor != null) {
            count--;
            continue;
          }
          String javaStr = cond.inv.format_using(OutputFormat.JAVA);
          String daikonStr = cond.inv.format_using(OutputFormat.DAIKON);
          String escStr = cond.inv.format_using(OutputFormat.ESCJAVA);
          String simplifyStr = cond.inv.format_using(OutputFormat.SIMPLIFY);
          allConds.add(combineDummy(condIndex, "<dummy> " + daikonStr, escStr, simplifyStr));
          //           allConds.add(condIndex);
          if (count > 0) {
            conjunctionJava.append(" && ");
            conjunctionDaikon.append(" and ");
            conjunctionESC.append(" && ");
            conjunctionSimplify.append(" ");
          }
          conjunctionJava.append(javaStr);
          conjunctionDaikon.append(daikonStr);
          conjunctionESC.append(escStr);
          conjunctionSimplify.append(simplifyStr);
        }
        conjunctionSimplify.append(")");
        String conj = conjunctionJava.toString();
        // Avoid inserting self-contradictory conditions such as "x == 1 &&
        // x == 2", or conjunctions of only a single condition.
        if (count < 2
            || contradict_inv_pattern.matcher(conj).find()
            || useless_inv_pattern_1.matcher(conj).find()
            || useless_inv_pattern_2.matcher(conj).find()) {
          // System.out.println("Suppressing: " + conj);
        } else {
          allConds.add(
              combineDummy(
                  conjunctionJava.toString(),
                  conjunctionDaikon.toString(),
                  conjunctionESC.toString(),
                  conjunctionSimplify.toString()));
        }
      }

      if (allConds.size() > 0) {
        pw.println();
        pw.println("PPT_NAME " + pptname);
        for (String s : allConds) {
          pw.println(s);
        }
      }
      allConds.clear();
    }

    pw.flush();
  }