Exemplo n.º 1
0
bool TermEnumeration::isClosedEnumerableType(TypeNode tn)
{
  std::unordered_map<TypeNode, bool, TypeNodeHashFunction>::iterator it =
      d_typ_closed_enum.find(tn);
  if (it == d_typ_closed_enum.end())
  {
    d_typ_closed_enum[tn] = true;
    bool ret = true;
    if (tn.isArray() || tn.isSort() || tn.isCodatatype() || tn.isFunction())
    {
      ret = false;
    }
    else if (tn.isSet())
    {
      ret = isClosedEnumerableType(tn.getSetElementType());
    }
    else if (tn.isDatatype())
    {
      const Datatype& dt = ((DatatypeType)(tn).toType()).getDatatype();
      for (unsigned i = 0; i < dt.getNumConstructors(); i++)
      {
        for (unsigned j = 0; j < dt[i].getNumArgs(); j++)
        {
          TypeNode ctn = TypeNode::fromType(dt[i][j].getRangeType());
          if (tn != ctn && !isClosedEnumerableType(ctn))
          {
            ret = false;
            break;
          }
        }
        if (!ret)
        {
          break;
        }
      }
    }
    
    // other parametric sorts go here
    
    d_typ_closed_enum[tn] = ret;
    return ret;
  }
  else
  {
    return it->second;
  }
}
Exemplo n.º 2
0
Node TheoryModel::getModelValue(TNode n, bool hasBoundVars) const
{
  Assert(n.getKind() != kind::FORALL && n.getKind() != kind::EXISTS);
  if(n.getKind() == kind::LAMBDA) {
    NodeManager* nm = NodeManager::currentNM();
    Node body = getModelValue(n[1], true);
    // This is a bit ugly, but cache inside simplifier can change, so can't be const
    // The ite simplifier is needed to get rid of artifacts created by Boolean terms
    body = const_cast<ITESimplifier*>(&d_iteSimp)->simpITE(body);
    body = Rewriter::rewrite(body);
    return nm->mkNode(kind::LAMBDA, n[0], body);
  }
  if(n.isConst() || (hasBoundVars && n.getKind() == kind::BOUND_VARIABLE)) {
    return n;
  }

  TypeNode t = n.getType();
  if (t.isFunction() || t.isPredicate()) {
    if (d_enableFuncModels) {
      std::map< Node, Node >::const_iterator it = d_uf_models.find(n);
      if (it != d_uf_models.end()) {
        // Existing function
        return it->second;
      }
      // Unknown function symbol: return LAMBDA x. c, where c is the first constant in the enumeration of the range type
      vector<TypeNode> argTypes = t.getArgTypes();
      vector<Node> args;
      NodeManager* nm = NodeManager::currentNM();
      for (unsigned i = 0; i < argTypes.size(); ++i) {
        args.push_back(nm->mkBoundVar(argTypes[i]));
      }
      Node boundVarList = nm->mkNode(kind::BOUND_VAR_LIST, args);
      TypeEnumerator te(t.getRangeType());
      return nm->mkNode(kind::LAMBDA, boundVarList, *te);
    }
    // TODO: if func models not enabled, throw an error?
    Unreachable();
  }

  if (n.getNumChildren() > 0) {
    std::vector<Node> children;
    if (n.getKind() == APPLY_UF) {
      Node op = getModelValue(n.getOperator(), hasBoundVars);
      children.push_back(op);
    }
    else if (n.getMetaKind() == kind::metakind::PARAMETERIZED) {
      children.push_back(n.getOperator());
    }
    //evaluate the children
    for (unsigned i = 0; i < n.getNumChildren(); ++i) {
      Node val = getModelValue(n[i], hasBoundVars);
      children.push_back(val);
    }
    Node val = Rewriter::rewrite(NodeManager::currentNM()->mkNode(n.getKind(), children));
    Assert(hasBoundVars || val.isConst());
    return val;
  }

  if (!d_equalityEngine.hasTerm(n)) {
    // Unknown term - return first enumerated value for this type
    TypeEnumerator te(n.getType());
    return *te;
  }
  Node val = d_equalityEngine.getRepresentative(n);
  Assert(d_reps.find(val) != d_reps.end());
  std::map< Node, Node >::const_iterator it = d_reps.find( val );
  if( it!=d_reps.end() ){
    return it->second;
  }else{
    return Node::null();
  }
}