Exemplo n.º 1
0
static ExpressionPtr makeIsNull(AnalysisResultConstPtr ar,
                                LocationPtr loc, ExpressionPtr exp,
                                bool invert) {
  /* Replace "$x === null" with an is_null call; this requires slightly
   * less work at runtime. */
  ExpressionListPtr expList =
    ExpressionListPtr(new ExpressionList(exp->getScope(), loc));
  expList->insertElement(exp);

  SimpleFunctionCallPtr call
    (new SimpleFunctionCall(exp->getScope(), loc,
                            "is_null", false, expList, ExpressionPtr()));

  call->setValid();
  call->setActualType(Type::Boolean);
  call->setupScopes(ar);

  ExpressionPtr result(call);
  if (invert) {
    result = ExpressionPtr(new UnaryOpExpression(
                             exp->getScope(), loc,
                             result, '!', true));
  }

  return result;
}
Exemplo n.º 2
0
ExpressionPtr Expression::replaceValue(ExpressionPtr rep) {
  if (hasContext(Expression::RefValue) &&
      isRefable(true) && !rep->isRefable(true)) {
    /*
      An assignment isRefable, but the rhs may not be. Need this to
      prevent "bad pass by reference" errors.
    */
    ExpressionListPtr el(new ExpressionList(getScope(), getRange(),
                                            ExpressionList::ListKindWrapped));
    el->addElement(rep);
    rep->clearContext(AssignmentRHS);
    rep = el;
  }
  if (rep->is(KindOfSimpleVariable) && !is(KindOfSimpleVariable)) {
    static_pointer_cast<SimpleVariable>(rep)->setAlwaysStash();
  }
  rep->copyContext(m_context & ~(DeadStore|AccessContext));
  if (TypePtr t1 = getType()) {
    if (TypePtr t2 = rep->getType()) {
      if (!Type::SameType(t1, t2)) {
        rep->setExpectedType(t1);
      }
    }
  }

  if (rep->getScope() != getScope()) {
    rep->resetScope(getScope());
  }

  return rep;
}
Exemplo n.º 3
0
ExpressionPtr Expression::replaceValue(ExpressionPtr rep, bool noWarn) {
  if (hasContext(Expression::RefValue) &&
      isRefable(true) && !rep->isRefable(true)) {
    /*
      An assignment isRefable, but the rhs may not be. Need this to
      prevent "bad pass by reference" errors.
    */
    auto el = std::make_shared<ExpressionList>(
      getScope(), getRange(), noWarn ?
      ExpressionList::ListKindWrappedNoWarn : ExpressionList::ListKindWrapped);
    el->addElement(rep);
    rep->clearContext(AssignmentRHS);
    rep = el;
  }
  if (rep->is(KindOfSimpleVariable) && !is(KindOfSimpleVariable)) {
    static_pointer_cast<SimpleVariable>(rep)->setAlwaysStash();
  }
  rep->copyContext(m_context & ~(DeadStore|AccessContext));

  if (rep->getScope() != getScope()) {
    rep->resetScope(getScope());
  }

  return rep;
}
Exemplo n.º 4
0
void RefDict::visit(ExpressionPtr e) {
  if (!first_pass) {
    // only need to record expressions once
    return;
  }

  if (e->getScope()->inPseudoMain()) {
    // bail out for psuedomain
    return;
  }

  if (!e->is(Expression::KindOfSimpleVariable)) {
    // only need to record simple variables
    return;
  }

  SimpleVariablePtr ptr(static_pointer_cast<SimpleVariable>(e));

  if (ptr->isSuperGlobal() || ptr->isThis()) {
    // don't both recording for super globals or this
    return;
  }

  // Good to go
  if (m_am.insertForDict(e)) {
    record(e);
  }
}
Exemplo n.º 5
0
void StaticStatement::analyzeProgram(AnalysisResultPtr ar) {
  m_exp->analyzeProgram(ar);
  if (ar->getPhase() == AnalysisResult::AnalyzeAll) {
    BlockScopePtr scope = getScope();
    for (int i = 0; i < m_exp->getCount(); i++) {
      ExpressionPtr exp = (*m_exp)[i];
      ExpressionPtr variable;
      ExpressionPtr value;
      // turn static $a; into static $a = null;
      if (exp->is(Expression::KindOfSimpleVariable)) {
        variable = dynamic_pointer_cast<SimpleVariable>(exp);
        exp = AssignmentExpressionPtr
          (new AssignmentExpression(exp->getScope(), exp->getLocation(),
                                    variable,
                                    CONSTANT("null"),
                                    false));
        (*m_exp)[i] = exp;
      }
      always_assert(exp->is(Expression::KindOfAssignmentExpression));
      AssignmentExpressionPtr assignment_exp =
        dynamic_pointer_cast<AssignmentExpression>(exp);
      variable = assignment_exp->getVariable();
      value = assignment_exp->getValue();
      SimpleVariablePtr var = dynamic_pointer_cast<SimpleVariable>(variable);
      // set the Declaration context here instead of all over this file - this phase
      // is the first to run
      var->setContext(Expression::Declaration);
      Symbol *sym = var->getSymbol();
      sym->setStaticInitVal(value);
    }
  }
}
Exemplo n.º 6
0
/**
 * Appends the given expression to end of the m_capturedExpressions list
 * and creates a new expression with the same scope and source location
 * that represents a reference to a query parameter. Query parameters do
 * not have a source code equivalent, but inform the query processor that
 * this expression represents the ith argument value, where i is zero based
 * and forms the last character of the special string @query_param_i.
 */
SimpleVariablePtr CaptureExtractor::newQueryParamRef(ExpressionPtr ae) {
  assert(ae != nullptr);
  char count = '0' + m_capturedExpressions.size();
  std::string pname = "@query_param_";
  pname.push_back(count);
  auto param =
    std::make_shared<SimpleVariable>(ae->getScope(), ae->getRange(), pname);
  m_capturedExpressions.push_back(ae);
  return param;
}
static ExpressionPtr makeIsNull(AnalysisResultConstPtr ar,
                                const Location::Range& r, ExpressionPtr exp,
                                bool invert) {
  /* Replace "$x === null" with an is_null call; this requires slightly
   * less work at runtime. */
  auto expList = std::make_shared<ExpressionList>(exp->getScope(), r);
  expList->insertElement(exp);

  auto call =
    std::make_shared<SimpleFunctionCall>(
      exp->getScope(), r, "is_null", false, expList, ExpressionPtr());

  call->setValid();
  call->setupScopes(ar);

  if (!invert) return call;

  return std::make_shared<UnaryOpExpression>(
    exp->getScope(), r, call, '!', true);
}
Exemplo n.º 8
0
bool StatementList::mergeConcatAssign() {
  if (Option::LocalCopyProp) {
    return false;
  } else {
    // check for vector string concat assignment such as
    //   $space = " ";
    //   $a .= "hello";
    //   $a .= $space;
    //   $a .= "world!";
    // turn into (for constant folding and concat sequence)
    //   $a .= " " . "hello " . $space . "world!";
    unsigned int i = 0;
    bool merged = false;
    do {
      std::string lhsName;
      int length = 0;
      for (; i < m_stmts.size(); i++) {
        StatementPtr stmt = m_stmts[i];
        if (!stmt->is(Statement::KindOfExpStatement)) break;
        ExpStatementPtr expStmt = dynamic_pointer_cast<ExpStatement>(stmt);
        ExpressionPtr exp = expStmt->getExpression();

        // check the first assignment
        if (exp->is(Expression::KindOfAssignmentExpression)) {
          AssignmentExpressionPtr assignment_exp =
            dynamic_pointer_cast<AssignmentExpression>(exp);
          ExpressionPtr variable = assignment_exp->getVariable();
          ExpressionPtr value = assignment_exp->getValue();
          std::string variableName = variable->getText();
          if (variableName.find("->") != std::string::npos) break;
          if (value->hasEffect()) break;
          // cannot turn $a .= $b; a .= $a into $a .= $b . $a;
          if (value->getText().find(variableName) != std::string::npos) break;
          if (lhsName.empty()) {
            lhsName = variable->getText();
            length++;
            continue;
          } else {
            break;
          }
        } else if (!exp->is(Expression::KindOfBinaryOpExpression)) {
          break;
        }
        BinaryOpExpressionPtr binaryOpExp =
          dynamic_pointer_cast<BinaryOpExpression>(exp);
        if (binaryOpExp->getOp() != T_CONCAT_EQUAL) break;
        ExpressionPtr exp1 = binaryOpExp->getExp1();
        std::string exp1Text = exp1->getText();
        if (exp1Text.find("->") != std::string::npos) break;
        ExpressionPtr exp2 = binaryOpExp->getExp2();
        if (exp2->hasEffect()) break;
        if (exp2->getText().find(exp1Text) != std::string::npos) break;
        if (lhsName.empty()) {
          lhsName = exp1Text;
          length++;
        } else if (lhsName == exp1Text) {
          length++;
        } else {
          break;
        }
      }
      if (length > 1) {
        // replace m_stmts[j] to m_stmts[i - 1] with a new statement
        unsigned j = i - length;
        ExpStatementPtr expStmt;
        ExpressionPtr exp;
        BinaryOpExpressionPtr binaryOpExp;
        ExpressionPtr var;
        ExpressionPtr exp1;
        ExpressionPtr exp2;
        bool isAssignment = false;
        expStmt = dynamic_pointer_cast<ExpStatement>(m_stmts[j++]);
        exp = expStmt->getExpression();
        if (exp->is(Expression::KindOfAssignmentExpression)) {
          isAssignment = true;
          AssignmentExpressionPtr assignment_exp =
            dynamic_pointer_cast<AssignmentExpression>(exp);
          var = assignment_exp->getVariable();
          exp1 = assignment_exp->getValue();
        } else {
          binaryOpExp = dynamic_pointer_cast<BinaryOpExpression>(exp);
          var = binaryOpExp->getExp1();
          exp1 = binaryOpExp->getExp2();
        }

        for (; j < i; j++) {
          expStmt = dynamic_pointer_cast<ExpStatement>(m_stmts[j]);
          exp = expStmt->getExpression();
          binaryOpExp = dynamic_pointer_cast<BinaryOpExpression>(exp);
          exp2 = binaryOpExp->getExp2();
          exp1 = BinaryOpExpressionPtr
            (new BinaryOpExpression(getScope(), getLocation(),
                                    Expression::KindOfBinaryOpExpression,
                                    exp1, exp2, '.'));
        }
        if (isAssignment) {
          exp = AssignmentExpressionPtr
            (new AssignmentExpression(exp->getScope(), exp->getLocation(),
                                      Expression::KindOfAssignmentExpression,
                                      var, exp1,
                                      false));
        } else {
          exp = BinaryOpExpressionPtr
            (new BinaryOpExpression(getScope(), getLocation(),
                                    Expression::KindOfBinaryOpExpression,
                                    var, exp1, T_CONCAT_EQUAL));
        }
        expStmt = ExpStatementPtr
          (new ExpStatement(getScope(), getLocation(),
                            Statement::KindOfExpStatement, exp));

        m_stmts[i - length] = expStmt;
        for (j = i - (length - 1); i > j; i--) removeElement(j);
        merged = true;
      } else if (length == 0) {
        i++;
      }
    } while (i < m_stmts.size());
    return merged;
  }
}
Exemplo n.º 9
0
static ExpressionPtr cloneForInlineRecur(InlineCloneInfo &info,
                                         ExpressionPtr exp,
                                         const std::string &prefix,
                                         AnalysisResultConstPtr ar,
                                         FunctionScopePtr scope) {
  exp->getOriginalScope(); // make sure to cache the original scope
  exp->setBlockScope(scope);
  for (int i = 0, n = exp->getKidCount(); i < n; i++) {
    if (ExpressionPtr k = exp->getNthExpr(i)) {
      exp->setNthKid(i, cloneForInlineRecur(info, k, prefix, ar, scope));
    }
  }
  StaticClassName *scn = dynamic_cast<StaticClassName*>(exp.get());
  if (scn && scn->isStatic() && !info.staticClass.empty()) {
    scn->resolveStatic(info.staticClass);
  }
  switch (exp->getKindOf()) {
  case Expression::KindOfSimpleVariable:
    {
      SimpleVariablePtr sv(dynamic_pointer_cast<SimpleVariable>(exp));
      if (sv->isSuperGlobal()) break;
      string name;
      if (sv->isThis()) {
        if (!info.callWithThis) {
          if (!sv->hasContext(Expression::ObjectContext)) {
            exp = sv->makeConstant(ar, "null");
          } else {
            // This will produce the wrong error
            // we really want a "throw_fatal" ast node.
            exp = sv->makeConstant(ar, "null");
          }
          break;
        }
        if (info.localThis.empty()) break;
        name = info.localThis;
      } else {
        name = prefix + sv->getName();
      }
      SimpleVariablePtr rep(new SimpleVariable(
                              exp->getScope(), exp->getLocation(), name));
      rep->copyContext(sv);
      rep->updateSymbol(SimpleVariablePtr());
      rep->getSymbol()->setHidden();
      // Conservatively set flags to prevent
      // the alias manager from getting confused.
      // On the next pass, it will correct the values,
      // and optimize appropriately.
      rep->getSymbol()->setUsed();
      rep->getSymbol()->setReferenced();
      if (exp->getContext() & (Expression::LValue|
                               Expression::RefValue|
                               Expression::RefParameter)) {
        info.sepm[name] = rep;
      }
      exp = rep;
    }
    break;
  case Expression::KindOfObjectMethodExpression:
  {
    FunctionCallPtr call(
      static_pointer_cast<FunctionCall>(exp));
    if (call->getFuncScope() == info.func) {
      call->setNoInline();
    }
    break;
  }
  case Expression::KindOfSimpleFunctionCall:
    {
      SimpleFunctionCallPtr call(static_pointer_cast<SimpleFunctionCall>(exp));
      call->addLateDependencies(ar);
      call->setLocalThis(info.localThis);
      if (call->getFuncScope() == info.func) {
        call->setNoInline();
      }
    }
  default:
    break;
  }
  return exp;
}
Exemplo n.º 10
0
void RefDict::updateAccess(ExpressionPtr e) {
  always_assert(!e->getScope()->inPseudoMain());

  int eid     = e->getCanonID();
  int context = e->getContext();

  if (first_pass) {
    if (!e->is(Expression::KindOfSimpleVariable) &&
        !e->is(Expression::KindOfDynamicVariable)) return;

    e->clearAvailable();
    e->clearReferencedValid();
    e->clearReferenced();

    SimpleVariablePtr ptr(dynamic_pointer_cast<SimpleVariable>(e));
    if (ptr && (ptr->isSuperGlobal() || ptr->isThis())) return;

    if (e->is(Expression::KindOfSimpleVariable)) {
      if (BitOps::get_bit(eid, m_referenced)) {
        e->setReferenced();
      } else if (!BitOps::get_bit(eid, m_killed)) {
        // use as a temp place holder
        e->setAvailable();
      }
    }
  }

  // let the first pass information propagate for both passes, since
  // we need it in both contexts
  if (context & Expression::RefAssignmentLHS ||
      context & Expression::RefValue ||
      context & Expression::RefParameter ||
      ((context & Expression::Declaration) == Expression::Declaration)) {
    if (e->is(Expression::KindOfSimpleVariable)) {
      BitOps::set_bit(eid, m_referenced, true);
      BitOps::set_bit(eid, m_killed, false);
    } else {
      // for dynamic variables, we must assume the worst
      BitOps::set(size(), m_referenced, -1);
      BitOps::set(size(), m_killed, 0);
    }
  } else if (e->is(Expression::KindOfSimpleVariable) &&
             context & Expression::LValue &&
             context & Expression::UnsetContext) {
    BitOps::set_bit(eid, m_referenced, false);
    BitOps::set_bit(eid, m_killed, true);
  }

  if (first_pass) return;

  // now we're on the second pass

  if (context & Expression::AssignmentLHS ||
      context & Expression::OprLValue) {
    // we dealt with this node as a store expression
    return;
  }

  int cls = e->getExprClass();

  bool isRhsNeeded = false;
  bool canKill     = false;

  ExpressionPtr lhs;
  ExpressionPtr rhs;

  if (cls & Expression::Store) {
    // we care about two cases here
    switch (e->getKindOf()) {
      case Expression::KindOfAssignmentExpression:
        // $x = ...
        {
          AssignmentExpressionPtr assign(
              static_pointer_cast<AssignmentExpression>(e));
          lhs = assign->getVariable();
          rhs = assign->getValue();
          isRhsNeeded = Expression::CheckNeededRHS(rhs);
          canKill = true;
        }
        break;
      case Expression::KindOfBinaryOpExpression:
        // $x += ...
        {
          BinaryOpExpressionPtr binop(
              static_pointer_cast<BinaryOpExpression>(e));
          if (binop->getOp() == T_PLUS_EQUAL) {
            lhs = binop->getExp1();
            rhs = binop->getExp2();
            isRhsNeeded = Expression::CheckNeededRHS(rhs);
          }
        }
        break;
      default:
        break;
    }
  }

  bool isLhsSimpleVar = false;
  bool isLhsDynamic   = false;
  bool isRefd         = false;
  if (lhs) {
    isLhsSimpleVar = lhs->is(Expression::KindOfSimpleVariable);

    // TODO: can a variable only be simple or dynamic?
    // If so, this is un-necessary
    isLhsDynamic   = lhs->is(Expression::KindOfDynamicVariable);

    if (isLhsSimpleVar) {
      // clean up the LHS AST
      lhs->clearAvailable();
      lhs->clearNeeded();
      lhs->clearNeededValid();

      if (BitOps::get_bit(lhs->getCanonID(), m_obj)) {
        lhs->setNeeded();
        lhs->setNeededValid();
      } else if (!BitOps::get_bit(lhs->getCanonID(), m_noobj)) {
        lhs->setAvailable();
      }
    }

    if (lhs->isReferencedValid() && lhs->isReferenced() && isRhsNeeded) {
      // could we possibly have modified another referenced variable?
      isRefd = true;
    }

    if (isLhsSimpleVar && isRhsNeeded) {
      // we see this case:
      // $x = new ...
      // so we mark $x as being needed
      BitOps::set_bit(lhs->getCanonID(), m_obj, true);
      BitOps::set_bit(lhs->getCanonID(), m_noobj, false);
    } else if (isLhsSimpleVar && canKill && !isRhsNeeded) {
      // we saw an assignment that was of the form
      // $x = <primitive>
      // we can now set $x to be not an object
      BitOps::set_bit(lhs->getCanonID(), m_obj, false);
      BitOps::set_bit(lhs->getCanonID(), m_noobj, true);
    }
  }

  if (isLhsDynamic && isRhsNeeded) {
    // in this case, we must set EVERY variable to contain an object
    BitOps::set(size(), m_obj, -1 /* true for each bit */);
    BitOps::set(size(), m_noobj, 0 /* false for each bit */);

    // we're done, since it can be no worse (no more conservative) than this
    return;
  }

  // do we see a load which could cause the value of this expr to be changed?
  // for example:
  // function foo(&$x) { $x = 10; }
  // $x = 30;
  // foo($x); /* <-- this is what we care about */
  if ((cls & (Expression::Load|Expression::Call)) &&
      (context & (Expression::RefValue|Expression::DeepReference))) {
    isRefd = true;
  }

  // we want to propagate this information to other simple vars we see
  if (e->is(Expression::KindOfSimpleVariable)) {
    // clean up the AST
    e->clearAvailable();
    e->clearNeeded();
    e->clearNeededValid();

    SimpleVariablePtr svp(static_pointer_cast<SimpleVariable>(e));
    if (svp->isSuperGlobal() || svp->isThis()) return;

    // update the AST to *before* the modification
    if (BitOps::get_bit(eid, m_obj)) {
      e->setNeeded();
      e->setNeededValid();
    } else if (!BitOps::get_bit(eid, m_noobj)) {
      // use as a temp place holder
      e->setAvailable();
    }

    if (context & Expression::LValue &&
        context & Expression::UnsetContext) {
      always_assert(!isRefd);
      // unset($x);
      BitOps::set_bit(eid, m_obj, false);
      BitOps::set_bit(eid, m_noobj, true);
    } else if (isRefd ||
        ((context & Expression::Declaration) == Expression::Declaration)) {
      // if a simple variable has isRefd, then we need to mark it
      // as potentially containing an object.
      // also, if the simple variable is in global context
      // then we also mark it as potentially containing an object
      BitOps::set_bit(eid, m_obj, true);
      BitOps::set_bit(eid, m_noobj, false);
    }
  }

  if (isRefd) {
    // do a scan for every simple variable referenced value
    // in the dictionary and mark it as potentially
    // containing an object (in the bit vector)
    for (int i = size(); i--; ) {
      if (ExpressionPtr e = get(i)) {
        always_assert(e->is(Expression::KindOfSimpleVariable));
        always_assert(((unsigned int)i) == e->getCanonID());
        if (BitOps::get_bit(i, m_referenced)) {
          BitOps::set_bit(i, m_obj, true);
          BitOps::set_bit(i, m_noobj, false);
        }
      }
    }
  }
}