bool
ExpressionList::flattenLiteralStrings(vector<ExpressionPtr> &literals) const {
  for (unsigned i = 0; i < m_exps.size(); i++) {
    ExpressionPtr e = m_exps[i];
    if (e->is(Expression::KindOfArrayPairExpression)) {
      ArrayPairExpressionPtr ap = dynamic_pointer_cast<ArrayPairExpression>(e);
      if (ap->getName()) return false;
      e = ap->getValue();
    }
    if (e->is(Expression::KindOfUnaryOpExpression)) {
      UnaryOpExpressionPtr unary = dynamic_pointer_cast<UnaryOpExpression>(e);
      if (unary->getOp() == T_ARRAY) {
        ExpressionListPtr el =
          dynamic_pointer_cast<ExpressionList>(unary->getExpression());
        if (!el->flattenLiteralStrings(literals)) {
          return false;
        }
      }
    }
    else if (e->isLiteralString()) {
      literals.push_back(e);
    } else {
      return false;
    }
  }
  return true;
}

void AssignmentExpression::onParseRecur(AnalysisResultConstPtr ar,
                                        ClassScopePtr scope) {
  // This is that much we can do during parse phase.
  TypePtr type;
  if (m_value->is(Expression::KindOfScalarExpression)) {
    type = static_pointer_cast<ScalarExpression>(m_value)->inferenceImpl(
      ar, Type::Some, false);
  } else if (m_value->is(Expression::KindOfUnaryOpExpression)) {
    UnaryOpExpressionPtr uexp =
      dynamic_pointer_cast<UnaryOpExpression>(m_value);
    if (uexp->getOp() == T_ARRAY) {
      type = Type::Array;
    }
  }
  if (!type) type = Type::Some;

  if (m_variable->is(Expression::KindOfConstantExpression)) {
    // ...as in ClassConstant statement
    // We are handling this one here, not in ClassConstant, purely because
    // we need "value" to store in constant table.
    ConstantExpressionPtr exp =
      dynamic_pointer_cast<ConstantExpression>(m_variable);
    scope->getConstants()->add(exp->getName(), type, m_value, ar, m_variable);
  } else if (m_variable->is(Expression::KindOfSimpleVariable)) {
    SimpleVariablePtr var = dynamic_pointer_cast<SimpleVariable>(m_variable);
    scope->getVariables()->add(var->getName(), type, true, ar,
                               shared_from_this(), scope->getModifiers());
    var->clearContext(Declaration); // to avoid wrong CodeError
  } else {
    ASSERT(false); // parse phase shouldn't handle anything else
  }
}

int BinaryOpExpression::getConcatList(ExpressionPtrVec &ev, ExpressionPtr exp,
                                      bool &hasVoid) {
  if (!exp->hasCPPTemp()) {
    if (exp->is(Expression::KindOfUnaryOpExpression)) {
      UnaryOpExpressionPtr u = static_pointer_cast<UnaryOpExpression>(exp);
      if (u->getOp() == '(') {
        return getConcatList(ev, u->getExpression(), hasVoid);
      }
    } else if (exp->is(Expression::KindOfBinaryOpExpression)) {
      BinaryOpExpressionPtr b = static_pointer_cast<BinaryOpExpression>(exp);
      if (b->getOp() == '.') {
        return getConcatList(ev, b->getExp1(), hasVoid) +
          getConcatList(ev, b->getExp2(), hasVoid);
      }
    } else if (exp->is(Expression::KindOfEncapsListExpression)) {
      EncapsListExpressionPtr e =
        static_pointer_cast<EncapsListExpression>(exp);
      if (e->getType() != '`') {
        ExpressionListPtr el = e->getExpressions();
        int num = 0;
        for (int i = 0, s = el->getCount(); i < s; i++) {
          ExpressionPtr exp = (*el)[i];
          num += getConcatList(ev, exp, hasVoid);
        }
        return num;
      }
    }
  }

  ev.push_back(exp);
  bool isVoid = !exp->getActualType();
  hasVoid |= isVoid;
  return isVoid ? 0 : 1;
}

int BinaryOpExpression::getConcatList(ExpressionPtrVec &ev, ExpressionPtr exp,
                                      bool &hasVoid) {
  if (!exp->hasCPPTemp()) {
    if (exp->is(Expression::KindOfUnaryOpExpression)) {
      UnaryOpExpressionPtr u = static_pointer_cast<UnaryOpExpression>(exp);
      if (u->getOp() == '(') {
        return getConcatList(ev, u->getExpression(), hasVoid);
      }
    } else if (exp->is(Expression::KindOfBinaryOpExpression)) {
      BinaryOpExpressionPtr b = static_pointer_cast<BinaryOpExpression>(exp);
      if (b->getOp() == '.') {
        if (b->getExp1()->is(Expression::KindOfSimpleVariable) &&
            b->getExp1()->isLocalExprAltered() &&
            !b->getExp1()->hasCPPTemp() &&
            b->getExp2()->hasEffect() &&
            !b->getExp2()->hasCPPTemp()) {
          /*
            In this case, the simple variable must be evaluated
            after b->getExp2(). But when we output a concat list we
            explicitly order the expressions from left to right.
          */
        } else {
          return getConcatList(ev, b->getExp1(), hasVoid) +
            getConcatList(ev, b->getExp2(), hasVoid);
        }
      }
    } else if (exp->is(Expression::KindOfEncapsListExpression)) {
      EncapsListExpressionPtr e =
        static_pointer_cast<EncapsListExpression>(exp);
      if (e->getType() != '`') {
        ExpressionListPtr el = e->getExpressions();
        int num = 0;
        for (int i = 0, s = el->getCount(); i < s; i++) {
          ExpressionPtr exp = (*el)[i];
          num += getConcatList(ev, exp, hasVoid);
        }
        return num;
      }
    }
  } else if (!exp->getActualType()) {
    return 0;
  }

  ev.push_back(exp);
  bool isVoid = !exp->getActualType();
  hasVoid |= isVoid;
  return isVoid ? 0 : 1;
}

bool Option::GetArrayElements(ExpressionPtr value, ExpressionListPtr &out) {
  UnaryOpExpressionPtr v = dynamic_pointer_cast<UnaryOpExpression>(value);
  if (!v || v->getOp() != T_ARRAY) {
    Logger::Error("Line %d: invalid array: %s", value->getLocation()->line1,
                  value->getText().c_str());
    return false;
  }

  ExpressionPtr exp = v->getExpression();
  out = dynamic_pointer_cast<ExpressionList>(exp);
  if (!out) {
    Logger::Error("Line %d: invalid array: %s", value->getLocation()->line1,
                  value->getText().c_str());
    return false;
  }

  return true;
}

void Parser::onUnaryOpExp(Token *out, Token *operand, int op, bool front) {
  switch (op) {
  case T_INCLUDE:
  case T_INCLUDE_ONCE:
  case T_REQUIRE:
  case T_REQUIRE_ONCE:
    {
      IncludeExpressionPtr exp = NEW_EXP(IncludeExpression, operand->exp, op);
      out->exp = exp;
      exp->onParse(m_ar);
    }
    break;
  default:
    {
      UnaryOpExpressionPtr exp = NEW_EXP(UnaryOpExpression, operand->exp, op,
                                         front);
      out->exp = exp;
      exp->onParse(m_ar);
    }
    break;
  }
}

bool Option::Load(map<string, int> &option, ExpressionPtr value) {
  ExpressionListPtr elements;
  if (!GetArrayElements(value, elements)) return false;

  for (int i = 0; i < elements->getCount(); i++) {
    ExpressionPtr e = (*elements)[i];
    ArrayPairExpressionPtr pair = dynamic_pointer_cast<ArrayPairExpression>(e);

    bool negative = false;
    ScalarExpressionPtr n, v;
    if (pair) n = dynamic_pointer_cast<ScalarExpression>(pair->getName());
    if (pair) {
      if (pair->getValue()->is(Expression::KindOfUnaryOpExpression)) {
        UnaryOpExpressionPtr una =
          dynamic_pointer_cast<UnaryOpExpression>(pair->getValue());
        if (una->getOp() != '+' && una->getOp() != '-') {
          Logger::Error("Line %d: invalid integer: %s",
                        una->getLocation()->line1, una->getText().c_str());
          return false;
        }

        v = dynamic_pointer_cast<ScalarExpression>(una->getExpression());
        if (una->getOp() == '-') {
          negative = true;
        }
      } else {
        v = dynamic_pointer_cast<ScalarExpression>(pair->getValue());
      }
    }

    if (!pair || !n || !v || !n->isLiteralString() || !v->isLiteralInteger()) {
      Logger::Error("Line %d: invalid element: %s", e->getLocation()->line1,
                    e->getText().c_str());
      return false;
    }

    if (negative) {
      option[n->getLiteralString()] = - v->getLiteralInteger();
    } else {
      option[n->getLiteralString()] = v->getLiteralInteger();
    }
  }

  return true;
}

/**
 * If the unary operation is not PHP specific, but something a query
 * processor can handle (+ - ! ~), then rewrite the operand to something
 * the query processor can evaluate (such as a query parameter reference)
 * and rewrite the entire expression to use the rewritten operand.
 * If the rewritten operand is the same as the original operand, just
 * return the expression as is.
 */
ExpressionPtr CaptureExtractor::rewriteUnary(UnaryOpExpressionPtr ue) {
  assert (ue != nullptr);
  if (!ue->getFront()) return nullptr;
  switch (ue->getOp()) {
    case '+':
    case '-':
    case '!':
    case '~':
      break; // Could be something the query processor can handle
    default:
      return newQueryParamRef(ue);
  }
  auto expr = ue->getExpression();
  auto newExpr = rewrite(expr);
  if (expr == newExpr) return ue;
  return std::make_shared<UnaryOpExpression>(
    ue->getScope(), ue->getRange(), newExpr, ue->getOp(), true);
}

//.........这里部分代码省略.........
    }
    break;

  case Expression::KindOfBinaryOpExpression: {
    BinaryOpExpressionPtr bop = spc(BinaryOpExpression, e);

    int rop = getOpForAssignmentOp(bop->getOp());
    if (rop) {
      ExpressionPtr lhs = bop->getExp1();
      ExpressionPtr rep;
      if (bop->getContext() & Expression::DeadStore) {
        Construct::recomputeEffects();
        ExpressionPtr rhs = bop->getExp2()->clone();
        lhs = lhs->clone();
        lhs->clearContext(Expression::LValue);
        lhs->clearContext(Expression::NoLValueWrapper);
        lhs->clearContext(Expression::OprLValue);
        rep = ExpressionPtr
          (new BinaryOpExpression(e->getLocation(),
                                  Expression::KindOfBinaryOpExpression,
                                  lhs, rhs, rop));

      } else {
        ExpressionPtr alt;
        int interf = findInterf(lhs, true, alt);
        if (interf == SameAccess &&
            alt->is(Expression::KindOfAssignmentExpression)) {
          ExpressionPtr op0 = spc(AssignmentExpression,alt)->getValue();
          if (op0->is(Expression::KindOfScalarExpression)) {
            ExpressionPtr op1 = bop->getExp2();
            ExpressionPtr rhs
              (new BinaryOpExpression(e->getLocation(),
                                      Expression::KindOfBinaryOpExpression,
                                      op0->clone(), op1->clone(), rop));

            lhs = lhs->clone();
            lhs->clearContext(Expression::OprLValue);
            rep = ExpressionPtr
              (new AssignmentExpression(e->getLocation(),
                                        Expression::KindOfAssignmentExpression,
                                        lhs, rhs, false));
          }
        }
      }
      if (rep) {
        ExpressionPtr c = canonicalizeRecur(rep);
        return c ? c : rep;
      }
      add(m_bucketMap[0], e);
    } else {
      getCanonical(e);
    }
    break;
  }

  case Expression::KindOfUnaryOpExpression:
    {
      UnaryOpExpressionPtr uop = spc(UnaryOpExpression, e);
      switch (uop->getOp()) {
      case T_INC:
      case T_DEC:
        if (uop->getContext() & Expression::DeadStore) {
          Construct::recomputeEffects();
          ExpressionPtr val = uop->getExpression()->clone();
          val->clearContext(Expression::LValue);
          val->clearContext(Expression::NoLValueWrapper);
          val->clearContext(Expression::OprLValue);
          if (uop->getFront()) {
            ExpressionPtr inc
              (new ScalarExpression(uop->getLocation(),
                                    Expression::KindOfScalarExpression,
                                    T_LNUMBER, string("1")));

            val = ExpressionPtr
              (new BinaryOpExpression(uop->getLocation(),
                                      Expression::KindOfBinaryOpExpression,
                                      val, inc,
                                      uop->getOp() == T_INC ? '+' : '-'));

          }

          ExpressionPtr r = canonicalizeRecur(val);
          return r ? r : val;
        }
        add(m_bucketMap[0], e);
        break;
      default:
        getCanonical(e);
        break;
      }
      break;
    }

  default:
    getCanonical(e);
    break;
  }

  return ExpressionPtr();
}