C++ TNode::eqNode方法代码示例

bool CoreSolver::NotifyClass::eqNotifyTriggerTermEquality(TheoryId tag, TNode t1, TNode t2, bool value) {
  Debug("bitvector::core") << "NotifyClass::eqNotifyTriggerTermMerge(" << t1 << ", " << t2 << ")" << std::endl;
  if (value) {
    return d_solver.storePropagation(t1.eqNode(t2));
  } else {
    return d_solver.storePropagation(t1.eqNode(t2).notNode());
  }
}

/** assert equality */
void TheoryModel::assertEquality(TNode a, TNode b, bool polarity ){
  if (a == b && polarity) {
    return;
  }
  Trace("model-builder-assertions") << "(assert " << (polarity ? "(= " : "(not (= ") << a << " " << b << (polarity ? "));" : ")));") << endl;
  d_equalityEngine.assertEquality( a.eqNode(b), polarity, Node::null() );
  Assert(d_equalityEngine.consistent());
}

void TheoryUF::conflict(TNode a, TNode b) {
  if (a.getKind() == kind::CONST_BOOLEAN) {
    d_conflictNode = explain(a.iffNode(b));
  } else {
    d_conflictNode = explain(a.eqNode(b));
  }
  d_out->conflict(d_conflictNode);
  d_conflict = true;
}

bool SharedTermsDatabase::propagateSharedEquality(TheoryId theory, TNode a, TNode b, bool value)
{
  Debug("shared-terms-database") << "SharedTermsDatabase::newEquality(" << theory << "," << a << "," << b << ", " << (value ? "true" : "false") << ")" << endl;

  if (d_inConflict) {
    return false;
  }

  // Propagate away
  Node equality = a.eqNode(b);
  if (value) {
    d_theoryEngine->assertToTheory(equality, equality, theory, THEORY_BUILTIN);
  } else {
    d_theoryEngine->assertToTheory(equality.notNode(), equality.notNode(), theory, THEORY_BUILTIN);
  }

  // As you were
  return true;
}

void TheoryUFTim::registerTerm(TNode n) {

  Debug("uf") << "uf: begin registerTerm(" << n << ")" << std::endl;

  d_registered.push_back(n);

  ECData* ecN;

  if(n.getAttribute(ECAttr(), ecN)) {
    /* registerTerm(n) is only called when a node has not been seen in the
     * current context.  ECAttr() is not a context-dependent attribute.
     * When n.hasAttribute(ECAttr(),...) is true on a registerTerm(n) call,
     * then it must be the case that this attribute was created in a previous
     * and no longer valid context. Because of this we have to reregister the
     * predecessors lists.
     * Also we do not have to worry about duplicates because all of the Link*
     * setup before are removed when the context n was setup in was popped out
     * of. All we are going to do here are sanity checks.
     */

    /*
     * Consider the following chain of events:
     * 1) registerTerm(n) is called on node n where n : f(m) in context level X,
     * 2) A new ECData is created on the heap, ecN,
     * 3) n is added to the predessecor list of m in context level X,
     * 4) We pop out of X,
     * 5) n is removed from the predessecor list of m because this is context
     *    dependent, the Link* will be destroyed and pointers to the Link
     *    structs in the ECData objects will be updated.
     * 6) registerTerm(n) is called on node n in context level Y,
     * 7) If n.hasAttribute(ECAttr(), &ecN), then ecN is still around,
     *    but the predecessor list is not
     *
     * The above assumes that the code is working correctly.
     */
    Assert(ecN->getFirst() == NULL,
           "Equivalence class data exists for the node being registered.  "
           "Expected getFirst() == NULL.  "
           "This data is either already in use or was not properly maintained "
           "during backtracking");
    /*Assert(ecN->getLast() == NULL,
           "Equivalence class data exists for the node being registered.  "
           "Expected getLast() == NULL.  "
           "This data is either already in use or was not properly maintained "
           "during backtracking.");*/
    Assert(ecN->isClassRep(),
           "Equivalence class data exists for the node being registered.  "
           "Expected isClassRep() to be true.  "
           "This data is either already in use or was not properly maintained "
           "during backtracking");
    Assert(ecN->getWatchListSize() == 0,
           "Equivalence class data exists for the node being registered.  "
           "Expected getWatchListSize() == 0.  "
           "This data is either already in use or was not properly maintained "
           "during backtracking");
  } else {
    //The attribute does not exist, so it is created and set
    ecN = new (true) ECData(getContext(), n);
    n.setAttribute(ECAttr(), ecN);
  }

  /* If the node is an APPLY_UF, we need to add it to the predecessor list
   * of its children.
   */
  if(n.getKind() == APPLY_UF) {
    TNode::iterator cIter = n.begin();

    for(; cIter != n.end(); ++cIter) {
      TNode child = *cIter;

      /* Because this can be called after nodes have been merged, we need
       * to lookup the representative in the UnionFind datastructure.
       */
      ECData* ecChild = ccFind(child.getAttribute(ECAttr()));

      /* Because this can be called after nodes have been merged we may need
       * to be merged with other predecessors of the equivalence class.
       */
      for(Link* Px = ecChild->getFirst(); Px != NULL; Px = Px->d_next ) {
        if(equiv(n, Px->d_data)) {
          Node pend = n.eqNode(Px->d_data);
          d_pending.push_back(pend);
        }
      }

      ecChild->addPredecessor(n);
    }
  }
  Debug("uf") << "uf: end registerTerm(" << n << ")" << std::endl;

}

//.........这里部分代码省略.........
      if(processed.find(*i) == processed.end()) {
        // unprocessed child
        workList.push_back(*i);
        unprocessedChildren = true;
      }
    }

    if(unprocessedChildren) {
      continue;
    }

    workList.pop_back();
    // has node n been processed in the meantime ?
    if(processed.find(n) != processed.end()) {
      continue;
    }
    processed.insert(n);

    // == DIAMONDS ==

    Debug("diamonds") << "===================== looking at" << endl
                      << n << endl;

    // binary OR of binary ANDs of EQUALities
    if(n.getKind() == kind::OR && n.getNumChildren() == 2 &&
       n[0].getKind() == kind::AND && n[0].getNumChildren() == 2 &&
       n[1].getKind() == kind::AND && n[1].getNumChildren() == 2 &&
       (n[0][0].getKind() == kind::EQUAL || n[0][0].getKind() == kind::IFF) &&
       (n[0][1].getKind() == kind::EQUAL || n[0][1].getKind() == kind::IFF) &&
       (n[1][0].getKind() == kind::EQUAL || n[1][0].getKind() == kind::IFF) &&
       (n[1][1].getKind() == kind::EQUAL || n[1][1].getKind() == kind::IFF)) {
      // now we have (a = b && c = d) || (e = f && g = h)

      Debug("diamonds") << "has form of a diamond!" << endl;

      TNode
        a = n[0][0][0], b = n[0][0][1],
        c = n[0][1][0], d = n[0][1][1],
        e = n[1][0][0], f = n[1][0][1],
        g = n[1][1][0], h = n[1][1][1];

      // test that one of {a, b} = one of {c, d}, and make "b" the
      // shared node (i.e. put in the form (a = b && b = d))
      // note we don't actually care about the shared ones, so the
      // "swaps" below are one-sided, ignoring b and c
      if(a == c) {
        a = b;
      } else if(a == d) {
        a = b;
        d = c;
      } else if(b == c) {
        // nothing to do
      } else if(b == d) {
        d = c;
      } else {
        // condition not satisfied
        Debug("diamonds") << "+ A fails" << endl;
        continue;
      }

      Debug("diamonds") << "+ A holds" << endl;

      // same: one of {e, f} = one of {g, h}, and make "f" the
      // shared node (i.e. put in the form (e = f && f = h))
      if(e == g) {
        e = f;
      } else if(e == h) {
        e = f;
        h = g;
      } else if(f == g) {
        // nothing to do
      } else if(f == h) {
        h = g;
      } else {
        // condition not satisfied
        Debug("diamonds") << "+ B fails" << endl;
        continue;
      }

      Debug("diamonds") << "+ B holds" << endl;

      // now we have (a = b && b = d) || (e = f && f = h)
      // test that {a, d} == {e, h}
      if( (a == e && d == h) ||
          (a == h && d == e) ) {
        // learn: n implies a == d
        Debug("diamonds") << "+ C holds" << endl;
        Node newEquality = a.getType().isBoolean() ? a.iffNode(d) : a.eqNode(d);
        Debug("diamonds") << "  ==> " << newEquality << endl;
        learned << n.impNode(newEquality);
      } else {
        Debug("diamonds") << "+ C fails" << endl;
      }
    }
  }

  if(options::ufSymmetryBreaker()) {
    d_symb.assertFormula(n);
  }
}/* TheoryUF::ppStaticLearn() */

void UnconstrainedSimplifier::processUnconstrained()
{
  TNodeSet::iterator it = d_unconstrained.begin(), iend = d_unconstrained.end();
  vector<TNode> workList;
  for ( ; it != iend; ++it) {
    workList.push_back(*it);
  }
  Node currentSub;
  TNode parent;
  bool swap;
  bool isSigned;
  bool strict;
  vector<TNode> delayQueueLeft;
  vector<Node> delayQueueRight;

  TNode current = workList.back();
  workList.pop_back();
  for (;;) {
    Assert(d_visitedOnce.find(current) != d_visitedOnce.end());
    parent = d_visitedOnce[current];
    if (!parent.isNull()) {
      swap = isSigned = strict = false;
      switch (parent.getKind()) {

        // If-then-else operator - any two unconstrained children makes the parent unconstrained
        case kind::ITE: {
          Assert(parent[0] == current || parent[1] == current || parent[2] == current);
          bool uCond = parent[0] == current || d_unconstrained.find(parent[0]) != d_unconstrained.end();
          bool uThen = parent[1] == current || d_unconstrained.find(parent[1]) != d_unconstrained.end();
          bool uElse = parent[2] == current || d_unconstrained.find(parent[2]) != d_unconstrained.end();
          if ((uCond && uThen) || (uCond && uElse) || (uThen && uElse)) {
            if (d_unconstrained.find(parent) == d_unconstrained.end() &&
                !d_substitutions.hasSubstitution(parent)) {
              ++d_numUnconstrainedElim;
              if (uThen) {
                if (parent[1] != current) {
                  if (parent[1].isVar()) {
                    currentSub = parent[1];
                  }
                  else {
                    Assert(d_substitutions.hasSubstitution(parent[1]));
                    currentSub = d_substitutions.apply(parent[1]);
                  }
                }
                else if (currentSub.isNull()) {
                  currentSub = current;
                }
              }
              else if (parent[2] != current) {
                if (parent[2].isVar()) {
                  currentSub = parent[2];
                }
                else {
                  Assert(d_substitutions.hasSubstitution(parent[2]));
                  currentSub = d_substitutions.apply(parent[2]);
                }
              }
              else if (currentSub.isNull()) {
                currentSub = current;
              }
              current = parent;
            }
            else {
              currentSub = Node();
            }
          }
          else if (uCond) {
            Cardinality card = parent.getType().getCardinality();
            if (card.isFinite() && !card.isLargeFinite() && card.getFiniteCardinality() == 2) {
              // Special case: condition is unconstrained, then and else are different, and total cardinality of the type is 2, then the result
              // is unconstrained
              Node test;
              if (parent.getType().isBoolean()) {
                test = Rewriter::rewrite(parent[1].iffNode(parent[2]));
              }
              else {
                test = Rewriter::rewrite(parent[1].eqNode(parent[2]));
              }
              if (test == NodeManager::currentNM()->mkConst<bool>(false)) {
                ++d_numUnconstrainedElim;
                if (currentSub.isNull()) {
                  currentSub = current;
                }
                currentSub = newUnconstrainedVar(parent.getType(), currentSub);
                current = parent;
              }
            }
          }
          break;
        }

        // Comparisons that return a different type - assuming domains are larger than 1, any
        // unconstrained child makes parent unconstrained as well
        case kind::EQUAL:
          if (parent[0].getType() != parent[1].getType()) {
            TNode other = (parent[0] == current) ? parent[1] : parent[0];
            if (current.getType().isSubtypeOf(other.getType())) {
              break;
            }
          }
//.........这里部分代码省略.........