xref: /external/clang/include/clang/AST/RecursiveASTVisitor.h

//===--- RecursiveASTVisitor.h - Recursive AST Visitor ----------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  This file defines the RecursiveASTVisitor interface, which recursively
//  traverses the entire AST.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_AST_RECURSIVEASTVISITOR_H
#define LLVM_CLANG_AST_RECURSIVEASTVISITOR_H

#include "clang/AST/Attr.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclFriend.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclOpenMP.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/NestedNameSpecifier.h"
#include "clang/AST/Stmt.h"
#include "clang/AST/StmtCXX.h"
#include "clang/AST/StmtObjC.h"
#include "clang/AST/StmtOpenMP.h"
#include "clang/AST/TemplateBase.h"
#include "clang/AST/TemplateName.h"
#include "clang/AST/Type.h"
#include "clang/AST/TypeLoc.h"

// The following three macros are used for meta programming.  The code
// using them is responsible for defining macro OPERATOR().

// All unary operators.
#define UNARYOP_LIST()                                                         \
  OPERATOR(PostInc) OPERATOR(PostDec) OPERATOR(PreInc) OPERATOR(PreDec)        \
      OPERATOR(AddrOf) OPERATOR(Deref) OPERATOR(Plus) OPERATOR(Minus)          \
      OPERATOR(Not) OPERATOR(LNot) OPERATOR(Real) OPERATOR(Imag)               \
      OPERATOR(Extension)

// All binary operators (excluding compound assign operators).
#define BINOP_LIST()                                                           \
  OPERATOR(PtrMemD) OPERATOR(PtrMemI) OPERATOR(Mul) OPERATOR(Div)              \
      OPERATOR(Rem) OPERATOR(Add) OPERATOR(Sub) OPERATOR(Shl) OPERATOR(Shr)    \
      OPERATOR(LT) OPERATOR(GT) OPERATOR(LE) OPERATOR(GE) OPERATOR(EQ)         \
      OPERATOR(NE) OPERATOR(And) OPERATOR(Xor) OPERATOR(Or) OPERATOR(LAnd)     \
      OPERATOR(LOr) OPERATOR(Assign) OPERATOR(Comma)

// All compound assign operators.
#define CAO_LIST()                                                             \
  OPERATOR(Mul) OPERATOR(Div) OPERATOR(Rem) OPERATOR(Add) OPERATOR(Sub)        \
      OPERATOR(Shl) OPERATOR(Shr) OPERATOR(And) OPERATOR(Or) OPERATOR(Xor)

namespace clang {

// A helper macro to implement short-circuiting when recursing.  It
// invokes CALL_EXPR, which must be a method call, on the derived
// object (s.t. a user of RecursiveASTVisitor can override the method
// in CALL_EXPR).
#define TRY_TO(CALL_EXPR)                                                      \
  do {                                                                         \
    if (!getDerived().CALL_EXPR)                                               \
      return false;                                                            \
  } while (0)

/// \brief A class that does preorder depth-first traversal on the
/// entire Clang AST and visits each node.
///
/// This class performs three distinct tasks:
///   1. traverse the AST (i.e. go to each node);
///   2. at a given node, walk up the class hierarchy, starting from
///      the node's dynamic type, until the top-most class (e.g. Stmt,
///      Decl, or Type) is reached.
///   3. given a (node, class) combination, where 'class' is some base
///      class of the dynamic type of 'node', call a user-overridable
///      function to actually visit the node.
///
/// These tasks are done by three groups of methods, respectively:
///   1. TraverseDecl(Decl *x) does task #1.  It is the entry point
///      for traversing an AST rooted at x.  This method simply
///      dispatches (i.e. forwards) to TraverseFoo(Foo *x) where Foo
///      is the dynamic type of *x, which calls WalkUpFromFoo(x) and
///      then recursively visits the child nodes of x.
///      TraverseStmt(Stmt *x) and TraverseType(QualType x) work
///      similarly.
///   2. WalkUpFromFoo(Foo *x) does task #2.  It does not try to visit
///      any child node of x.  Instead, it first calls WalkUpFromBar(x)
///      where Bar is the direct parent class of Foo (unless Foo has
///      no parent), and then calls VisitFoo(x) (see the next list item).
///   3. VisitFoo(Foo *x) does task #3.
///
/// These three method groups are tiered (Traverse* > WalkUpFrom* >
/// Visit*).  A method (e.g. Traverse*) may call methods from the same
/// tier (e.g. other Traverse*) or one tier lower (e.g. WalkUpFrom*).
/// It may not call methods from a higher tier.
///
/// Note that since WalkUpFromFoo() calls WalkUpFromBar() (where Bar
/// is Foo's super class) before calling VisitFoo(), the result is
/// that the Visit*() methods for a given node are called in the
/// top-down order (e.g. for a node of type NamespaceDecl, the order will
/// be VisitDecl(), VisitNamedDecl(), and then VisitNamespaceDecl()).
///
/// This scheme guarantees that all Visit*() calls for the same AST
/// node are grouped together.  In other words, Visit*() methods for
/// different nodes are never interleaved.
///
/// Clients of this visitor should subclass the visitor (providing
/// themselves as the template argument, using the curiously recurring
/// template pattern) and override any of the Traverse*, WalkUpFrom*,
/// and Visit* methods for declarations, types, statements,
/// expressions, or other AST nodes where the visitor should customize
/// behavior.  Most users only need to override Visit*.  Advanced
/// users may override Traverse* and WalkUpFrom* to implement custom
/// traversal strategies.  Returning false from one of these overridden
/// functions will abort the entire traversal.
///
/// By default, this visitor tries to visit every part of the explicit
/// source code exactly once.  The default policy towards templates
/// is to descend into the 'pattern' class or function body, not any
/// explicit or implicit instantiations.  Explicit specializations
/// are still visited, and the patterns of partial specializations
/// are visited separately.  This behavior can be changed by
/// overriding shouldVisitTemplateInstantiations() in the derived class
/// to return true, in which case all known implicit and explicit
/// instantiations will be visited at the same time as the pattern
/// from which they were produced.
template <typename Derived> class RecursiveASTVisitor {
public:
  /// \brief Return a reference to the derived class.
  Derived &getDerived() { return *static_cast<Derived *>(this); }

  /// \brief Return whether this visitor should recurse into
  /// template instantiations.
  bool shouldVisitTemplateInstantiations() const { return false; }

  /// \brief Return whether this visitor should recurse into the types of
  /// TypeLocs.
  bool shouldWalkTypesOfTypeLocs() const { return true; }

  /// \brief Return whether this visitor should recurse into implicit
  /// code, e.g., implicit constructors and destructors.
  bool shouldVisitImplicitCode() const { return false; }

  /// \brief Return whether \param S should be traversed using data recursion
  /// to avoid a stack overflow with extreme cases.
  bool shouldUseDataRecursionFor(Stmt *S) const {
    return isa<BinaryOperator>(S) || isa<UnaryOperator>(S) ||
           isa<CaseStmt>(S) || isa<CXXOperatorCallExpr>(S);
  }

  /// \brief Recursively visit a statement or expression, by
  /// dispatching to Traverse*() based on the argument's dynamic type.
  ///
  /// \returns false if the visitation was terminated early, true
  /// otherwise (including when the argument is NULL).
  bool TraverseStmt(Stmt *S);

  /// \brief Recursively visit a type, by dispatching to
  /// Traverse*Type() based on the argument's getTypeClass() property.
  ///
  /// \returns false if the visitation was terminated early, true
  /// otherwise (including when the argument is a Null type).
  bool TraverseType(QualType T);

  /// \brief Recursively visit a type with location, by dispatching to
  /// Traverse*TypeLoc() based on the argument type's getTypeClass() property.
  ///
  /// \returns false if the visitation was terminated early, true
  /// otherwise (including when the argument is a Null type location).
  bool TraverseTypeLoc(TypeLoc TL);

  /// \brief Recursively visit an attribute, by dispatching to
  /// Traverse*Attr() based on the argument's dynamic type.
  ///
  /// \returns false if the visitation was terminated early, true
  /// otherwise (including when the argument is a Null type location).
  bool TraverseAttr(Attr *At);

  /// \brief Recursively visit a declaration, by dispatching to
  /// Traverse*Decl() based on the argument's dynamic type.
  ///
  /// \returns false if the visitation was terminated early, true
  /// otherwise (including when the argument is NULL).
  bool TraverseDecl(Decl *D);

  /// \brief Recursively visit a C++ nested-name-specifier.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseNestedNameSpecifier(NestedNameSpecifier *NNS);

  /// \brief Recursively visit a C++ nested-name-specifier with location
  /// information.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS);

  /// \brief Recursively visit a name with its location information.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseDeclarationNameInfo(DeclarationNameInfo NameInfo);

  /// \brief Recursively visit a template name and dispatch to the
  /// appropriate method.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseTemplateName(TemplateName Template);

  /// \brief Recursively visit a template argument and dispatch to the
  /// appropriate method for the argument type.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  // FIXME: migrate callers to TemplateArgumentLoc instead.
  bool TraverseTemplateArgument(const TemplateArgument &Arg);

  /// \brief Recursively visit a template argument location and dispatch to the
  /// appropriate method for the argument type.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseTemplateArgumentLoc(const TemplateArgumentLoc &ArgLoc);

  /// \brief Recursively visit a set of template arguments.
  /// This can be overridden by a subclass, but it's not expected that
  /// will be needed -- this visitor always dispatches to another.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  // FIXME: take a TemplateArgumentLoc* (or TemplateArgumentListInfo) instead.
  bool TraverseTemplateArguments(const TemplateArgument *Args,
                                 unsigned NumArgs);

  /// \brief Recursively visit a constructor initializer.  This
  /// automatically dispatches to another visitor for the initializer
  /// expression, but not for the name of the initializer, so may
  /// be overridden for clients that need access to the name.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseConstructorInitializer(CXXCtorInitializer *Init);

  /// \brief Recursively visit a lambda capture.
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseLambdaCapture(LambdaExpr *LE, const LambdaCapture *C);

  /// \brief Recursively visit the body of a lambda expression.
  ///
  /// This provides a hook for visitors that need more context when visiting
  /// \c LE->getBody().
  ///
  /// \returns false if the visitation was terminated early, true otherwise.
  bool TraverseLambdaBody(LambdaExpr *LE);

  // ---- Methods on Attrs ----

  // \brief Visit an attribute.
  bool VisitAttr(Attr *A) { return true; }

// Declare Traverse* and empty Visit* for all Attr classes.
#define ATTR_VISITOR_DECLS_ONLY
#include "clang/AST/AttrVisitor.inc"
#undef ATTR_VISITOR_DECLS_ONLY

// ---- Methods on Stmts ----

// Declare Traverse*() for all concrete Stmt classes.
#define ABSTRACT_STMT(STMT)
#define STMT(CLASS, PARENT) bool Traverse##CLASS(CLASS *S);
#include "clang/AST/StmtNodes.inc"
  // The above header #undefs ABSTRACT_STMT and STMT upon exit.

  // Define WalkUpFrom*() and empty Visit*() for all Stmt classes.
  bool WalkUpFromStmt(Stmt *S) { return getDerived().VisitStmt(S); }
  bool VisitStmt(Stmt *S) { return true; }
#define STMT(CLASS, PARENT)                                                    \
  bool WalkUpFrom##CLASS(CLASS *S) {                                           \
    TRY_TO(WalkUpFrom##PARENT(S));                                             \
    TRY_TO(Visit##CLASS(S));                                                   \
    return true;                                                               \
  }                                                                            \
  bool Visit##CLASS(CLASS *S) { return true; }
#include "clang/AST/StmtNodes.inc"

// Define Traverse*(), WalkUpFrom*(), and Visit*() for unary
// operator methods.  Unary operators are not classes in themselves
// (they're all opcodes in UnaryOperator) but do have visitors.
#define OPERATOR(NAME)                                                         \
  bool TraverseUnary##NAME(UnaryOperator *S) {                                 \
    TRY_TO(WalkUpFromUnary##NAME(S));                                          \
    TRY_TO(TraverseStmt(S->getSubExpr()));                                     \
    return true;                                                               \
  }                                                                            \
  bool WalkUpFromUnary##NAME(UnaryOperator *S) {                               \
    TRY_TO(WalkUpFromUnaryOperator(S));                                        \
    TRY_TO(VisitUnary##NAME(S));                                               \
    return true;                                                               \
  }                                                                            \
  bool VisitUnary##NAME(UnaryOperator *S) { return true; }

  UNARYOP_LIST()
#undef OPERATOR

// Define Traverse*(), WalkUpFrom*(), and Visit*() for binary
// operator methods.  Binary operators are not classes in themselves
// (they're all opcodes in BinaryOperator) but do have visitors.
#define GENERAL_BINOP_FALLBACK(NAME, BINOP_TYPE)                               \
  bool TraverseBin##NAME(BINOP_TYPE *S) {                                      \
    TRY_TO(WalkUpFromBin##NAME(S));                                            \
    TRY_TO(TraverseStmt(S->getLHS()));                                         \
    TRY_TO(TraverseStmt(S->getRHS()));                                         \
    return true;                                                               \
  }                                                                            \
  bool WalkUpFromBin##NAME(BINOP_TYPE *S) {                                    \
    TRY_TO(WalkUpFrom##BINOP_TYPE(S));                                         \
    TRY_TO(VisitBin##NAME(S));                                                 \
    return true;                                                               \
  }                                                                            \
  bool VisitBin##NAME(BINOP_TYPE *S) { return true; }

#define OPERATOR(NAME) GENERAL_BINOP_FALLBACK(NAME, BinaryOperator)
  BINOP_LIST()
#undef OPERATOR

// Define Traverse*(), WalkUpFrom*(), and Visit*() for compound
// assignment methods.  Compound assignment operators are not
// classes in themselves (they're all opcodes in
// CompoundAssignOperator) but do have visitors.
#define OPERATOR(NAME)                                                         \
  GENERAL_BINOP_FALLBACK(NAME##Assign, CompoundAssignOperator)

  CAO_LIST()
#undef OPERATOR
#undef GENERAL_BINOP_FALLBACK

// ---- Methods on Types ----
// FIXME: revamp to take TypeLoc's rather than Types.

// Declare Traverse*() for all concrete Type classes.
#define ABSTRACT_TYPE(CLASS, BASE)
#define TYPE(CLASS, BASE) bool Traverse##CLASS##Type(CLASS##Type *T);
#include "clang/AST/TypeNodes.def"
  // The above header #undefs ABSTRACT_TYPE and TYPE upon exit.

  // Define WalkUpFrom*() and empty Visit*() for all Type classes.
  bool WalkUpFromType(Type *T) { return getDerived().VisitType(T); }
  bool VisitType(Type *T) { return true; }
#define TYPE(CLASS, BASE)                                                      \
  bool WalkUpFrom##CLASS##Type(CLASS##Type *T) {                               \
    TRY_TO(WalkUpFrom##BASE(T));                                               \
    TRY_TO(Visit##CLASS##Type(T));                                             \
    return true;                                                               \
  }                                                                            \
  bool Visit##CLASS##Type(CLASS##Type *T) { return true; }
#include "clang/AST/TypeNodes.def"

// ---- Methods on TypeLocs ----
// FIXME: this currently just calls the matching Type methods

// Declare Traverse*() for all concrete TypeLoc classes.
#define ABSTRACT_TYPELOC(CLASS, BASE)
#define TYPELOC(CLASS, BASE) bool Traverse##CLASS##TypeLoc(CLASS##TypeLoc TL);
#include "clang/AST/TypeLocNodes.def"
  // The above header #undefs ABSTRACT_TYPELOC and TYPELOC upon exit.

  // Define WalkUpFrom*() and empty Visit*() for all TypeLoc classes.
  bool WalkUpFromTypeLoc(TypeLoc TL) { return getDerived().VisitTypeLoc(TL); }
  bool VisitTypeLoc(TypeLoc TL) { return true; }

  // QualifiedTypeLoc and UnqualTypeLoc are not declared in
  // TypeNodes.def and thus need to be handled specially.
  bool WalkUpFromQualifiedTypeLoc(QualifiedTypeLoc TL) {
    return getDerived().VisitUnqualTypeLoc(TL.getUnqualifiedLoc());
  }
  bool VisitQualifiedTypeLoc(QualifiedTypeLoc TL) { return true; }
  bool WalkUpFromUnqualTypeLoc(UnqualTypeLoc TL) {
    return getDerived().VisitUnqualTypeLoc(TL.getUnqualifiedLoc());
  }
  bool VisitUnqualTypeLoc(UnqualTypeLoc TL) { return true; }

// Note that BASE includes trailing 'Type' which CLASS doesn't.
#define TYPE(CLASS, BASE)                                                      \
  bool WalkUpFrom##CLASS##TypeLoc(CLASS##TypeLoc TL) {                         \
    TRY_TO(WalkUpFrom##BASE##Loc(TL));                                         \
    TRY_TO(Visit##CLASS##TypeLoc(TL));                                         \
    return true;                                                               \
  }                                                                            \
  bool Visit##CLASS##TypeLoc(CLASS##TypeLoc TL) { return true; }
#include "clang/AST/TypeNodes.def"

// ---- Methods on Decls ----

// Declare Traverse*() for all concrete Decl classes.
#define ABSTRACT_DECL(DECL)
#define DECL(CLASS, BASE) bool Traverse##CLASS##Decl(CLASS##Decl *D);
#include "clang/AST/DeclNodes.inc"
  // The above header #undefs ABSTRACT_DECL and DECL upon exit.

  // Define WalkUpFrom*() and empty Visit*() for all Decl classes.
  bool WalkUpFromDecl(Decl *D) { return getDerived().VisitDecl(D); }
  bool VisitDecl(Decl *D) { return true; }
#define DECL(CLASS, BASE)                                                      \
  bool WalkUpFrom##CLASS##Decl(CLASS##Decl *D) {                               \
    TRY_TO(WalkUpFrom##BASE(D));                                               \
    TRY_TO(Visit##CLASS##Decl(D));                                             \
    return true;                                                               \
  }                                                                            \
  bool Visit##CLASS##Decl(CLASS##Decl *D) { return true; }
#include "clang/AST/DeclNodes.inc"

private:
  // These are helper methods used by more than one Traverse* method.
  bool TraverseTemplateParameterListHelper(TemplateParameterList *TPL);
#define DEF_TRAVERSE_TMPL_INST(TMPLDECLKIND)                                   \
  bool TraverseTemplateInstantiations(TMPLDECLKIND##TemplateDecl *D);
  DEF_TRAVERSE_TMPL_INST(Class)
  DEF_TRAVERSE_TMPL_INST(Var)
  DEF_TRAVERSE_TMPL_INST(Function)
#undef DEF_TRAVERSE_TMPL_INST
  bool TraverseTemplateArgumentLocsHelper(const TemplateArgumentLoc *TAL,
                                          unsigned Count);
  bool TraverseArrayTypeLocHelper(ArrayTypeLoc TL);
  bool TraverseRecordHelper(RecordDecl *D);
  bool TraverseCXXRecordHelper(CXXRecordDecl *D);
  bool TraverseDeclaratorHelper(DeclaratorDecl *D);
  bool TraverseDeclContextHelper(DeclContext *DC);
  bool TraverseFunctionHelper(FunctionDecl *D);
  bool TraverseVarHelper(VarDecl *D);
  bool TraverseOMPClause(OMPClause *C);
  bool TraverseOMPExecutableDirective(OMPExecutableDirective *S);
#define OPENMP_CLAUSE(Name, Class) bool Visit##Class(Class *C);
#include "clang/Basic/OpenMPKinds.def"
  /// \brief Process clauses with list of variables.
  template <typename T> void VisitOMPClauseList(T *Node);

  struct EnqueueJob {
    Stmt *S;
    Stmt::child_iterator StmtIt;

    EnqueueJob(Stmt *S) : S(S), StmtIt() {}
  };
  bool dataTraverse(Stmt *S);
  bool dataTraverseNode(Stmt *S, bool &EnqueueChildren);
};

template <typename Derived>
bool RecursiveASTVisitor<Derived>::dataTraverse(Stmt *S) {

  SmallVector<EnqueueJob, 16> Queue;
  Queue.push_back(S);

  while (!Queue.empty()) {
    EnqueueJob &job = Queue.back();
    Stmt *CurrS = job.S;
    if (!CurrS) {
      Queue.pop_back();
      continue;
    }

    if (getDerived().shouldUseDataRecursionFor(CurrS)) {
      if (job.StmtIt == Stmt::child_iterator()) {
        bool EnqueueChildren = true;
        if (!dataTraverseNode(CurrS, EnqueueChildren))
          return false;
        if (!EnqueueChildren) {
          Queue.pop_back();
          continue;
        }
        job.StmtIt = CurrS->child_begin();
      } else {
        ++job.StmtIt;
      }

      if (job.StmtIt != CurrS->child_end())
        Queue.push_back(*job.StmtIt);
      else
        Queue.pop_back();
      continue;
    }

    Queue.pop_back();
    TRY_TO(TraverseStmt(CurrS));
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::dataTraverseNode(Stmt *S,
                                                    bool &EnqueueChildren) {

// Dispatch to the corresponding WalkUpFrom* function only if the derived
// class didn't override Traverse* (and thus the traversal is trivial).
#define DISPATCH_WALK(NAME, CLASS, VAR)                                        \
  {                                                                            \
    bool (Derived::*DerivedFn)(CLASS *) = &Derived::Traverse##NAME;            \
    bool (Derived::*BaseFn)(CLASS *) = &RecursiveASTVisitor::Traverse##NAME;   \
    if (DerivedFn == BaseFn)                                                   \
      return getDerived().WalkUpFrom##NAME(static_cast<CLASS *>(VAR));         \
  }                                                                            \
  EnqueueChildren = false;                                                     \
  return getDerived().Traverse##NAME(static_cast<CLASS *>(VAR));

  if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(S)) {
    switch (BinOp->getOpcode()) {
#define OPERATOR(NAME)                                                         \
  case BO_##NAME:                                                              \
    DISPATCH_WALK(Bin##NAME, BinaryOperator, S);

      BINOP_LIST()
#undef OPERATOR

#define OPERATOR(NAME)                                                         \
  case BO_##NAME##Assign:                                                      \
    DISPATCH_WALK(Bin##NAME##Assign, CompoundAssignOperator, S);

      CAO_LIST()
#undef OPERATOR
    }
  } else if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(S)) {
    switch (UnOp->getOpcode()) {
#define OPERATOR(NAME)                                                         \
  case UO_##NAME:                                                              \
    DISPATCH_WALK(Unary##NAME, UnaryOperator, S);

      UNARYOP_LIST()
#undef OPERATOR
    }
  }

  // Top switch stmt: dispatch to TraverseFooStmt for each concrete FooStmt.
  switch (S->getStmtClass()) {
  case Stmt::NoStmtClass:
    break;
#define ABSTRACT_STMT(STMT)
#define STMT(CLASS, PARENT)                                                    \
  case Stmt::CLASS##Class:                                                     \
    DISPATCH_WALK(CLASS, CLASS, S);
#include "clang/AST/StmtNodes.inc"
  }

#undef DISPATCH_WALK

  return true;
}

#define DISPATCH(NAME, CLASS, VAR)                                             \
  return getDerived().Traverse##NAME(static_cast<CLASS *>(VAR))

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseStmt(Stmt *S) {
  if (!S)
    return true;

#define DISPATCH_STMT(NAME, CLASS, VAR) DISPATCH(NAME, CLASS, VAR)

  if (getDerived().shouldUseDataRecursionFor(S))
    return dataTraverse(S);

  // If we have a binary expr, dispatch to the subcode of the binop.  A smart
  // optimizer (e.g. LLVM) will fold this comparison into the switch stmt
  // below.
  if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(S)) {
    switch (BinOp->getOpcode()) {
#define OPERATOR(NAME)                                                         \
  case BO_##NAME:                                                              \
    DISPATCH_STMT(Bin##NAME, BinaryOperator, S);

      BINOP_LIST()
#undef OPERATOR
#undef BINOP_LIST

#define OPERATOR(NAME)                                                         \
  case BO_##NAME##Assign:                                                      \
    DISPATCH_STMT(Bin##NAME##Assign, CompoundAssignOperator, S);

      CAO_LIST()
#undef OPERATOR
#undef CAO_LIST
    }
  } else if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(S)) {
    switch (UnOp->getOpcode()) {
#define OPERATOR(NAME)                                                         \
  case UO_##NAME:                                                              \
    DISPATCH_STMT(Unary##NAME, UnaryOperator, S);

      UNARYOP_LIST()
#undef OPERATOR
#undef UNARYOP_LIST
    }
  }

  // Top switch stmt: dispatch to TraverseFooStmt for each concrete FooStmt.
  switch (S->getStmtClass()) {
  case Stmt::NoStmtClass:
    break;
#define ABSTRACT_STMT(STMT)
#define STMT(CLASS, PARENT)                                                    \
  case Stmt::CLASS##Class:                                                     \
    DISPATCH_STMT(CLASS, CLASS, S);
#include "clang/AST/StmtNodes.inc"
  }

  return true;
}

#undef DISPATCH_STMT

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseType(QualType T) {
  if (T.isNull())
    return true;

  switch (T->getTypeClass()) {
#define ABSTRACT_TYPE(CLASS, BASE)
#define TYPE(CLASS, BASE)                                                      \
  case Type::CLASS:                                                            \
    DISPATCH(CLASS##Type, CLASS##Type, const_cast<Type *>(T.getTypePtr()));
#include "clang/AST/TypeNodes.def"
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTypeLoc(TypeLoc TL) {
  if (TL.isNull())
    return true;

  switch (TL.getTypeLocClass()) {
#define ABSTRACT_TYPELOC(CLASS, BASE)
#define TYPELOC(CLASS, BASE)                                                   \
  case TypeLoc::CLASS:                                                         \
    return getDerived().Traverse##CLASS##TypeLoc(TL.castAs<CLASS##TypeLoc>());
#include "clang/AST/TypeLocNodes.def"
  }

  return true;
}

// Define the Traverse*Attr(Attr* A) methods
#define VISITORCLASS RecursiveASTVisitor
#include "clang/AST/AttrVisitor.inc"
#undef VISITORCLASS

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseDecl(Decl *D) {
  if (!D)
    return true;

  // As a syntax visitor, by default we want to ignore declarations for
  // implicit declarations (ones not typed explicitly by the user).
  if (!getDerived().shouldVisitImplicitCode() && D->isImplicit())
    return true;

  switch (D->getKind()) {
#define ABSTRACT_DECL(DECL)
#define DECL(CLASS, BASE)                                                      \
  case Decl::CLASS:                                                            \
    if (!getDerived().Traverse##CLASS##Decl(static_cast<CLASS##Decl *>(D)))    \
      return false;                                                            \
    break;
#include "clang/AST/DeclNodes.inc"
  }

  // Visit any attributes attached to this declaration.
  for (auto *I : D->attrs()) {
    if (!getDerived().TraverseAttr(I))
      return false;
  }
  return true;
}

#undef DISPATCH

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseNestedNameSpecifier(
    NestedNameSpecifier *NNS) {
  if (!NNS)
    return true;

  if (NNS->getPrefix())
    TRY_TO(TraverseNestedNameSpecifier(NNS->getPrefix()));

  switch (NNS->getKind()) {
  case NestedNameSpecifier::Identifier:
  case NestedNameSpecifier::Namespace:
  case NestedNameSpecifier::NamespaceAlias:
  case NestedNameSpecifier::Global:
    return true;

  case NestedNameSpecifier::TypeSpec:
  case NestedNameSpecifier::TypeSpecWithTemplate:
    TRY_TO(TraverseType(QualType(NNS->getAsType(), 0)));
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseNestedNameSpecifierLoc(
    NestedNameSpecifierLoc NNS) {
  if (!NNS)
    return true;

  if (NestedNameSpecifierLoc Prefix = NNS.getPrefix())
    TRY_TO(TraverseNestedNameSpecifierLoc(Prefix));

  switch (NNS.getNestedNameSpecifier()->getKind()) {
  case NestedNameSpecifier::Identifier:
  case NestedNameSpecifier::Namespace:
  case NestedNameSpecifier::NamespaceAlias:
  case NestedNameSpecifier::Global:
    return true;

  case NestedNameSpecifier::TypeSpec:
  case NestedNameSpecifier::TypeSpecWithTemplate:
    TRY_TO(TraverseTypeLoc(NNS.getTypeLoc()));
    break;
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseDeclarationNameInfo(
    DeclarationNameInfo NameInfo) {
  switch (NameInfo.getName().getNameKind()) {
  case DeclarationName::CXXConstructorName:
  case DeclarationName::CXXDestructorName:
  case DeclarationName::CXXConversionFunctionName:
    if (TypeSourceInfo *TSInfo = NameInfo.getNamedTypeInfo())
      TRY_TO(TraverseTypeLoc(TSInfo->getTypeLoc()));

    break;

  case DeclarationName::Identifier:
  case DeclarationName::ObjCZeroArgSelector:
  case DeclarationName::ObjCOneArgSelector:
  case DeclarationName::ObjCMultiArgSelector:
  case DeclarationName::CXXOperatorName:
  case DeclarationName::CXXLiteralOperatorName:
  case DeclarationName::CXXUsingDirective:
    break;
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateName(TemplateName Template) {
  if (DependentTemplateName *DTN = Template.getAsDependentTemplateName())
    TRY_TO(TraverseNestedNameSpecifier(DTN->getQualifier()));
  else if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
    TRY_TO(TraverseNestedNameSpecifier(QTN->getQualifier()));

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateArgument(
    const TemplateArgument &Arg) {
  switch (Arg.getKind()) {
  case TemplateArgument::Null:
  case TemplateArgument::Declaration:
  case TemplateArgument::Integral:
  case TemplateArgument::NullPtr:
    return true;

  case TemplateArgument::Type:
    return getDerived().TraverseType(Arg.getAsType());

  case TemplateArgument::Template:
  case TemplateArgument::TemplateExpansion:
    return getDerived().TraverseTemplateName(
        Arg.getAsTemplateOrTemplatePattern());

  case TemplateArgument::Expression:
    return getDerived().TraverseStmt(Arg.getAsExpr());

  case TemplateArgument::Pack:
    return getDerived().TraverseTemplateArguments(Arg.pack_begin(),
                                                  Arg.pack_size());
  }

  return true;
}

// FIXME: no template name location?
// FIXME: no source locations for a template argument pack?
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateArgumentLoc(
    const TemplateArgumentLoc &ArgLoc) {
  const TemplateArgument &Arg = ArgLoc.getArgument();

  switch (Arg.getKind()) {
  case TemplateArgument::Null:
  case TemplateArgument::Declaration:
  case TemplateArgument::Integral:
  case TemplateArgument::NullPtr:
    return true;

  case TemplateArgument::Type: {
    // FIXME: how can TSI ever be NULL?
    if (TypeSourceInfo *TSI = ArgLoc.getTypeSourceInfo())
      return getDerived().TraverseTypeLoc(TSI->getTypeLoc());
    else
      return getDerived().TraverseType(Arg.getAsType());
  }

  case TemplateArgument::Template:
  case TemplateArgument::TemplateExpansion:
    if (ArgLoc.getTemplateQualifierLoc())
      TRY_TO(getDerived().TraverseNestedNameSpecifierLoc(
          ArgLoc.getTemplateQualifierLoc()));
    return getDerived().TraverseTemplateName(
        Arg.getAsTemplateOrTemplatePattern());

  case TemplateArgument::Expression:
    return getDerived().TraverseStmt(ArgLoc.getSourceExpression());

  case TemplateArgument::Pack:
    return getDerived().TraverseTemplateArguments(Arg.pack_begin(),
                                                  Arg.pack_size());
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateArguments(
    const TemplateArgument *Args, unsigned NumArgs) {
  for (unsigned I = 0; I != NumArgs; ++I) {
    TRY_TO(TraverseTemplateArgument(Args[I]));
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseConstructorInitializer(
    CXXCtorInitializer *Init) {
  if (TypeSourceInfo *TInfo = Init->getTypeSourceInfo())
    TRY_TO(TraverseTypeLoc(TInfo->getTypeLoc()));

  if (Init->isWritten() || getDerived().shouldVisitImplicitCode())
    TRY_TO(TraverseStmt(Init->getInit()));
  return true;
}

template <typename Derived>
bool
RecursiveASTVisitor<Derived>::TraverseLambdaCapture(LambdaExpr *LE,
                                                    const LambdaCapture *C) {
  if (C->isInitCapture())
    TRY_TO(TraverseDecl(C->getCapturedVar()));
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseLambdaBody(LambdaExpr *LE) {
  TRY_TO(TraverseStmt(LE->getBody()));
  return true;
}

// ----------------- Type traversal -----------------

// This macro makes available a variable T, the passed-in type.
#define DEF_TRAVERSE_TYPE(TYPE, CODE)                                          \
  template <typename Derived>                                                  \
  bool RecursiveASTVisitor<Derived>::Traverse##TYPE(TYPE *T) {                 \
    TRY_TO(WalkUpFrom##TYPE(T));                                               \
    { CODE; }                                                                  \
    return true;                                                               \
  }

DEF_TRAVERSE_TYPE(BuiltinType, {})

DEF_TRAVERSE_TYPE(ComplexType, { TRY_TO(TraverseType(T->getElementType())); })

DEF_TRAVERSE_TYPE(PointerType, { TRY_TO(TraverseType(T->getPointeeType())); })

DEF_TRAVERSE_TYPE(BlockPointerType,
                  { TRY_TO(TraverseType(T->getPointeeType())); })

DEF_TRAVERSE_TYPE(LValueReferenceType,
                  { TRY_TO(TraverseType(T->getPointeeType())); })

DEF_TRAVERSE_TYPE(RValueReferenceType,
                  { TRY_TO(TraverseType(T->getPointeeType())); })

DEF_TRAVERSE_TYPE(MemberPointerType, {
  TRY_TO(TraverseType(QualType(T->getClass(), 0)));
  TRY_TO(TraverseType(T->getPointeeType()));
})

DEF_TRAVERSE_TYPE(AdjustedType, { TRY_TO(TraverseType(T->getOriginalType())); })

DEF_TRAVERSE_TYPE(DecayedType, { TRY_TO(TraverseType(T->getOriginalType())); })

DEF_TRAVERSE_TYPE(ConstantArrayType,
                  { TRY_TO(TraverseType(T->getElementType())); })

DEF_TRAVERSE_TYPE(IncompleteArrayType,
                  { TRY_TO(TraverseType(T->getElementType())); })

DEF_TRAVERSE_TYPE(VariableArrayType, {
  TRY_TO(TraverseType(T->getElementType()));
  TRY_TO(TraverseStmt(T->getSizeExpr()));
})

DEF_TRAVERSE_TYPE(DependentSizedArrayType, {
  TRY_TO(TraverseType(T->getElementType()));
  if (T->getSizeExpr())
    TRY_TO(TraverseStmt(T->getSizeExpr()));
})

DEF_TRAVERSE_TYPE(DependentSizedExtVectorType, {
  if (T->getSizeExpr())
    TRY_TO(TraverseStmt(T->getSizeExpr()));
  TRY_TO(TraverseType(T->getElementType()));
})

DEF_TRAVERSE_TYPE(VectorType, { TRY_TO(TraverseType(T->getElementType())); })

DEF_TRAVERSE_TYPE(ExtVectorType, { TRY_TO(TraverseType(T->getElementType())); })

DEF_TRAVERSE_TYPE(FunctionNoProtoType,
                  { TRY_TO(TraverseType(T->getReturnType())); })

DEF_TRAVERSE_TYPE(FunctionProtoType, {
  TRY_TO(TraverseType(T->getReturnType()));

  for (const auto &A : T->param_types()) {
    TRY_TO(TraverseType(A));
  }

  for (const auto &E : T->exceptions()) {
    TRY_TO(TraverseType(E));
  }
})

DEF_TRAVERSE_TYPE(UnresolvedUsingType, {})
DEF_TRAVERSE_TYPE(TypedefType, {})

DEF_TRAVERSE_TYPE(TypeOfExprType,
                  { TRY_TO(TraverseStmt(T->getUnderlyingExpr())); })

DEF_TRAVERSE_TYPE(TypeOfType, { TRY_TO(TraverseType(T->getUnderlyingType())); })

DEF_TRAVERSE_TYPE(DecltypeType,
                  { TRY_TO(TraverseStmt(T->getUnderlyingExpr())); })

DEF_TRAVERSE_TYPE(UnaryTransformType, {
  TRY_TO(TraverseType(T->getBaseType()));
  TRY_TO(TraverseType(T->getUnderlyingType()));
})

DEF_TRAVERSE_TYPE(AutoType, { TRY_TO(TraverseType(T->getDeducedType())); })

DEF_TRAVERSE_TYPE(RecordType, {})
DEF_TRAVERSE_TYPE(EnumType, {})
DEF_TRAVERSE_TYPE(TemplateTypeParmType, {})
DEF_TRAVERSE_TYPE(SubstTemplateTypeParmType, {})
DEF_TRAVERSE_TYPE(SubstTemplateTypeParmPackType, {})

DEF_TRAVERSE_TYPE(TemplateSpecializationType, {
  TRY_TO(TraverseTemplateName(T->getTemplateName()));
  TRY_TO(TraverseTemplateArguments(T->getArgs(), T->getNumArgs()));
})

DEF_TRAVERSE_TYPE(InjectedClassNameType, {})

DEF_TRAVERSE_TYPE(AttributedType,
                  { TRY_TO(TraverseType(T->getModifiedType())); })

DEF_TRAVERSE_TYPE(ParenType, { TRY_TO(TraverseType(T->getInnerType())); })

DEF_TRAVERSE_TYPE(ElaboratedType, {
  if (T->getQualifier()) {
    TRY_TO(TraverseNestedNameSpecifier(T->getQualifier()));
  }
  TRY_TO(TraverseType(T->getNamedType()));
})

DEF_TRAVERSE_TYPE(DependentNameType,
                  { TRY_TO(TraverseNestedNameSpecifier(T->getQualifier())); })

DEF_TRAVERSE_TYPE(DependentTemplateSpecializationType, {
  TRY_TO(TraverseNestedNameSpecifier(T->getQualifier()));
  TRY_TO(TraverseTemplateArguments(T->getArgs(), T->getNumArgs()));
})

DEF_TRAVERSE_TYPE(PackExpansionType, { TRY_TO(TraverseType(T->getPattern())); })

DEF_TRAVERSE_TYPE(ObjCInterfaceType, {})

DEF_TRAVERSE_TYPE(ObjCObjectType, {
  // We have to watch out here because an ObjCInterfaceType's base
  // type is itself.
  if (T->getBaseType().getTypePtr() != T)
    TRY_TO(TraverseType(T->getBaseType()));
})

DEF_TRAVERSE_TYPE(ObjCObjectPointerType,
                  { TRY_TO(TraverseType(T->getPointeeType())); })

DEF_TRAVERSE_TYPE(AtomicType, { TRY_TO(TraverseType(T->getValueType())); })

#undef DEF_TRAVERSE_TYPE

// ----------------- TypeLoc traversal -----------------

// This macro makes available a variable TL, the passed-in TypeLoc.
// If requested, it calls WalkUpFrom* for the Type in the given TypeLoc,
// in addition to WalkUpFrom* for the TypeLoc itself, such that existing
// clients that override the WalkUpFrom*Type() and/or Visit*Type() methods
// continue to work.
#define DEF_TRAVERSE_TYPELOC(TYPE, CODE)                                       \
  template <typename Derived>                                                  \
  bool RecursiveASTVisitor<Derived>::Traverse##TYPE##Loc(TYPE##Loc TL) {       \
    if (getDerived().shouldWalkTypesOfTypeLocs())                              \
      TRY_TO(WalkUpFrom##TYPE(const_cast<TYPE *>(TL.getTypePtr())));           \
    TRY_TO(WalkUpFrom##TYPE##Loc(TL));                                         \
    { CODE; }                                                                  \
    return true;                                                               \
  }

template <typename Derived>
bool
RecursiveASTVisitor<Derived>::TraverseQualifiedTypeLoc(QualifiedTypeLoc TL) {
  // Move this over to the 'main' typeloc tree.  Note that this is a
  // move -- we pretend that we were really looking at the unqualified
  // typeloc all along -- rather than a recursion, so we don't follow
  // the normal CRTP plan of going through
  // getDerived().TraverseTypeLoc.  If we did, we'd be traversing
  // twice for the same type (once as a QualifiedTypeLoc version of
  // the type, once as an UnqualifiedTypeLoc version of the type),
  // which in effect means we'd call VisitTypeLoc twice with the
  // 'same' type.  This solves that problem, at the cost of never
  // seeing the qualified version of the type (unless the client
  // subclasses TraverseQualifiedTypeLoc themselves).  It's not a
  // perfect solution.  A perfect solution probably requires making
  // QualifiedTypeLoc a wrapper around TypeLoc -- like QualType is a
  // wrapper around Type* -- rather than being its own class in the
  // type hierarchy.
  return TraverseTypeLoc(TL.getUnqualifiedLoc());
}

DEF_TRAVERSE_TYPELOC(BuiltinType, {})

// FIXME: ComplexTypeLoc is unfinished
DEF_TRAVERSE_TYPELOC(ComplexType, {
  TRY_TO(TraverseType(TL.getTypePtr()->getElementType()));
})

DEF_TRAVERSE_TYPELOC(PointerType,
                     { TRY_TO(TraverseTypeLoc(TL.getPointeeLoc())); })

DEF_TRAVERSE_TYPELOC(BlockPointerType,
                     { TRY_TO(TraverseTypeLoc(TL.getPointeeLoc())); })

DEF_TRAVERSE_TYPELOC(LValueReferenceType,
                     { TRY_TO(TraverseTypeLoc(TL.getPointeeLoc())); })

DEF_TRAVERSE_TYPELOC(RValueReferenceType,
                     { TRY_TO(TraverseTypeLoc(TL.getPointeeLoc())); })

// FIXME: location of base class?
// We traverse this in the type case as well, but how is it not reached through
// the pointee type?
DEF_TRAVERSE_TYPELOC(MemberPointerType, {
  TRY_TO(TraverseType(QualType(TL.getTypePtr()->getClass(), 0)));
  TRY_TO(TraverseTypeLoc(TL.getPointeeLoc()));
})

DEF_TRAVERSE_TYPELOC(AdjustedType,
                     { TRY_TO(TraverseTypeLoc(TL.getOriginalLoc())); })

DEF_TRAVERSE_TYPELOC(DecayedType,
                     { TRY_TO(TraverseTypeLoc(TL.getOriginalLoc())); })

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseArrayTypeLocHelper(ArrayTypeLoc TL) {
  // This isn't available for ArrayType, but is for the ArrayTypeLoc.
  TRY_TO(TraverseStmt(TL.getSizeExpr()));
  return true;
}

DEF_TRAVERSE_TYPELOC(ConstantArrayType, {
  TRY_TO(TraverseTypeLoc(TL.getElementLoc()));
  return TraverseArrayTypeLocHelper(TL);
})

DEF_TRAVERSE_TYPELOC(IncompleteArrayType, {
  TRY_TO(TraverseTypeLoc(TL.getElementLoc()));
  return TraverseArrayTypeLocHelper(TL);
})

DEF_TRAVERSE_TYPELOC(VariableArrayType, {
  TRY_TO(TraverseTypeLoc(TL.getElementLoc()));
  return TraverseArrayTypeLocHelper(TL);
})

DEF_TRAVERSE_TYPELOC(DependentSizedArrayType, {
  TRY_TO(TraverseTypeLoc(TL.getElementLoc()));
  return TraverseArrayTypeLocHelper(TL);
})

// FIXME: order? why not size expr first?
// FIXME: base VectorTypeLoc is unfinished
DEF_TRAVERSE_TYPELOC(DependentSizedExtVectorType, {
  if (TL.getTypePtr()->getSizeExpr())
    TRY_TO(TraverseStmt(TL.getTypePtr()->getSizeExpr()));
  TRY_TO(TraverseType(TL.getTypePtr()->getElementType()));
})

// FIXME: VectorTypeLoc is unfinished
DEF_TRAVERSE_TYPELOC(VectorType, {
  TRY_TO(TraverseType(TL.getTypePtr()->getElementType()));
})

// FIXME: size and attributes
// FIXME: base VectorTypeLoc is unfinished
DEF_TRAVERSE_TYPELOC(ExtVectorType, {
  TRY_TO(TraverseType(TL.getTypePtr()->getElementType()));
})

DEF_TRAVERSE_TYPELOC(FunctionNoProtoType,
                     { TRY_TO(TraverseTypeLoc(TL.getReturnLoc())); })

// FIXME: location of exception specifications (attributes?)
DEF_TRAVERSE_TYPELOC(FunctionProtoType, {
  TRY_TO(TraverseTypeLoc(TL.getReturnLoc()));

  const FunctionProtoType *T = TL.getTypePtr();

  for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) {
    if (TL.getParam(I)) {
      TRY_TO(TraverseDecl(TL.getParam(I)));
    } else if (I < T->getNumParams()) {
      TRY_TO(TraverseType(T->getParamType(I)));
    }
  }

  for (const auto &E : T->exceptions()) {
    TRY_TO(TraverseType(E));
  }
})

DEF_TRAVERSE_TYPELOC(UnresolvedUsingType, {})
DEF_TRAVERSE_TYPELOC(TypedefType, {})

DEF_TRAVERSE_TYPELOC(TypeOfExprType,
                     { TRY_TO(TraverseStmt(TL.getUnderlyingExpr())); })

DEF_TRAVERSE_TYPELOC(TypeOfType, {
  TRY_TO(TraverseTypeLoc(TL.getUnderlyingTInfo()->getTypeLoc()));
})

// FIXME: location of underlying expr
DEF_TRAVERSE_TYPELOC(DecltypeType, {
  TRY_TO(TraverseStmt(TL.getTypePtr()->getUnderlyingExpr()));
})

DEF_TRAVERSE_TYPELOC(UnaryTransformType, {
  TRY_TO(TraverseTypeLoc(TL.getUnderlyingTInfo()->getTypeLoc()));
})

DEF_TRAVERSE_TYPELOC(AutoType, {
  TRY_TO(TraverseType(TL.getTypePtr()->getDeducedType()));
})

DEF_TRAVERSE_TYPELOC(RecordType, {})
DEF_TRAVERSE_TYPELOC(EnumType, {})
DEF_TRAVERSE_TYPELOC(TemplateTypeParmType, {})
DEF_TRAVERSE_TYPELOC(SubstTemplateTypeParmType, {})
DEF_TRAVERSE_TYPELOC(SubstTemplateTypeParmPackType, {})

// FIXME: use the loc for the template name?
DEF_TRAVERSE_TYPELOC(TemplateSpecializationType, {
  TRY_TO(TraverseTemplateName(TL.getTypePtr()->getTemplateName()));
  for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
    TRY_TO(TraverseTemplateArgumentLoc(TL.getArgLoc(I)));
  }
})

DEF_TRAVERSE_TYPELOC(InjectedClassNameType, {})

DEF_TRAVERSE_TYPELOC(ParenType, { TRY_TO(TraverseTypeLoc(TL.getInnerLoc())); })

DEF_TRAVERSE_TYPELOC(AttributedType,
                     { TRY_TO(TraverseTypeLoc(TL.getModifiedLoc())); })

DEF_TRAVERSE_TYPELOC(ElaboratedType, {
  if (TL.getQualifierLoc()) {
    TRY_TO(TraverseNestedNameSpecifierLoc(TL.getQualifierLoc()));
  }
  TRY_TO(TraverseTypeLoc(TL.getNamedTypeLoc()));
})

DEF_TRAVERSE_TYPELOC(DependentNameType, {
  TRY_TO(TraverseNestedNameSpecifierLoc(TL.getQualifierLoc()));
})

DEF_TRAVERSE_TYPELOC(DependentTemplateSpecializationType, {
  if (TL.getQualifierLoc()) {
    TRY_TO(TraverseNestedNameSpecifierLoc(TL.getQualifierLoc()));
  }

  for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
    TRY_TO(TraverseTemplateArgumentLoc(TL.getArgLoc(I)));
  }
})

DEF_TRAVERSE_TYPELOC(PackExpansionType,
                     { TRY_TO(TraverseTypeLoc(TL.getPatternLoc())); })

DEF_TRAVERSE_TYPELOC(ObjCInterfaceType, {})

DEF_TRAVERSE_TYPELOC(ObjCObjectType, {
  // We have to watch out here because an ObjCInterfaceType's base
  // type is itself.
  if (TL.getTypePtr()->getBaseType().getTypePtr() != TL.getTypePtr())
    TRY_TO(TraverseTypeLoc(TL.getBaseLoc()));
})

DEF_TRAVERSE_TYPELOC(ObjCObjectPointerType,
                     { TRY_TO(TraverseTypeLoc(TL.getPointeeLoc())); })

DEF_TRAVERSE_TYPELOC(AtomicType, { TRY_TO(TraverseTypeLoc(TL.getValueLoc())); })

#undef DEF_TRAVERSE_TYPELOC

// ----------------- Decl traversal -----------------
//
// For a Decl, we automate (in the DEF_TRAVERSE_DECL macro) traversing
// the children that come from the DeclContext associated with it.
// Therefore each Traverse* only needs to worry about children other
// than those.

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseDeclContextHelper(DeclContext *DC) {
  if (!DC)
    return true;

  for (auto *Child : DC->decls()) {
    // BlockDecls and CapturedDecls are traversed through BlockExprs and
    // CapturedStmts respectively.
    if (!isa<BlockDecl>(Child) && !isa<CapturedDecl>(Child))
      TRY_TO(TraverseDecl(Child));
  }

  return true;
}

// This macro makes available a variable D, the passed-in decl.
#define DEF_TRAVERSE_DECL(DECL, CODE)                                          \
  template <typename Derived>                                                  \
  bool RecursiveASTVisitor<Derived>::Traverse##DECL(DECL *D) {                 \
    TRY_TO(WalkUpFrom##DECL(D));                                               \
    { CODE; }                                                                  \
    TRY_TO(TraverseDeclContextHelper(dyn_cast<DeclContext>(D)));               \
    return true;                                                               \
  }

DEF_TRAVERSE_DECL(AccessSpecDecl, {})

DEF_TRAVERSE_DECL(BlockDecl, {
  if (TypeSourceInfo *TInfo = D->getSignatureAsWritten())
    TRY_TO(TraverseTypeLoc(TInfo->getTypeLoc()));
  TRY_TO(TraverseStmt(D->getBody()));
  // This return statement makes sure the traversal of nodes in
  // decls_begin()/decls_end() (done in the DEF_TRAVERSE_DECL macro)
  // is skipped - don't remove it.
  return true;
})

DEF_TRAVERSE_DECL(CapturedDecl, {
  TRY_TO(TraverseStmt(D->getBody()));
  // This return statement makes sure the traversal of nodes in
  // decls_begin()/decls_end() (done in the DEF_TRAVERSE_DECL macro)
  // is skipped - don't remove it.
  return true;
})

DEF_TRAVERSE_DECL(EmptyDecl, {})

DEF_TRAVERSE_DECL(FileScopeAsmDecl,
                  { TRY_TO(TraverseStmt(D->getAsmString())); })

DEF_TRAVERSE_DECL(ImportDecl, {})

DEF_TRAVERSE_DECL(FriendDecl, {
  // Friend is either decl or a type.
  if (D->getFriendType())
    TRY_TO(TraverseTypeLoc(D->getFriendType()->getTypeLoc()));
  else
    TRY_TO(TraverseDecl(D->getFriendDecl()));
})

DEF_TRAVERSE_DECL(FriendTemplateDecl, {
  if (D->getFriendType())
    TRY_TO(TraverseTypeLoc(D->getFriendType()->getTypeLoc()));
  else
    TRY_TO(TraverseDecl(D->getFriendDecl()));
  for (unsigned I = 0, E = D->getNumTemplateParameters(); I < E; ++I) {
    TemplateParameterList *TPL = D->getTemplateParameterList(I);
    for (TemplateParameterList::iterator ITPL = TPL->begin(), ETPL = TPL->end();
         ITPL != ETPL; ++ITPL) {
      TRY_TO(TraverseDecl(*ITPL));
    }
  }
})

DEF_TRAVERSE_DECL(ClassScopeFunctionSpecializationDecl, {
  TRY_TO(TraverseDecl(D->getSpecialization()));

  if (D->hasExplicitTemplateArgs()) {
    const TemplateArgumentListInfo &args = D->templateArgs();
    TRY_TO(TraverseTemplateArgumentLocsHelper(args.getArgumentArray(),
                                              args.size()));
  }
})

DEF_TRAVERSE_DECL(LinkageSpecDecl, {})

DEF_TRAVERSE_DECL(ObjCPropertyImplDecl, {// FIXME: implement this
                                        })

DEF_TRAVERSE_DECL(StaticAssertDecl, {
  TRY_TO(TraverseStmt(D->getAssertExpr()));
  TRY_TO(TraverseStmt(D->getMessage()));
})

DEF_TRAVERSE_DECL(
    TranslationUnitDecl,
    {// Code in an unnamed namespace shows up automatically in
     // decls_begin()/decls_end().  Thus we don't need to recurse on
     // D->getAnonymousNamespace().
    })

DEF_TRAVERSE_DECL(NamespaceAliasDecl, {
  // We shouldn't traverse an aliased namespace, since it will be
  // defined (and, therefore, traversed) somewhere else.
  //
  // This return statement makes sure the traversal of nodes in
  // decls_begin()/decls_end() (done in the DEF_TRAVERSE_DECL macro)
  // is skipped - don't remove it.
  return true;
})

DEF_TRAVERSE_DECL(LabelDecl, {// There is no code in a LabelDecl.
                             })

DEF_TRAVERSE_DECL(
    NamespaceDecl,
    {// Code in an unnamed namespace shows up automatically in
     // decls_begin()/decls_end().  Thus we don't need to recurse on
     // D->getAnonymousNamespace().
    })

DEF_TRAVERSE_DECL(ObjCCompatibleAliasDecl, {// FIXME: implement
                                           })

DEF_TRAVERSE_DECL(ObjCCategoryDecl, {// FIXME: implement
                                    })

DEF_TRAVERSE_DECL(ObjCCategoryImplDecl, {// FIXME: implement
                                        })

DEF_TRAVERSE_DECL(ObjCImplementationDecl, {// FIXME: implement
                                          })

DEF_TRAVERSE_DECL(ObjCInterfaceDecl, {// FIXME: implement
                                     })

DEF_TRAVERSE_DECL(ObjCProtocolDecl, {// FIXME: implement
                                    })

DEF_TRAVERSE_DECL(ObjCMethodDecl, {
  if (D->getReturnTypeSourceInfo()) {
    TRY_TO(TraverseTypeLoc(D->getReturnTypeSourceInfo()->getTypeLoc()));
  }
  for (ObjCMethodDecl::param_iterator I = D->param_begin(), E = D->param_end();
       I != E; ++I) {
    TRY_TO(TraverseDecl(*I));
  }
  if (D->isThisDeclarationADefinition()) {
    TRY_TO(TraverseStmt(D->getBody()));
  }
  return true;
})

DEF_TRAVERSE_DECL(ObjCPropertyDecl, {// FIXME: implement
                                    })

DEF_TRAVERSE_DECL(UsingDecl, {
  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(D->getNameInfo()));
})

DEF_TRAVERSE_DECL(UsingDirectiveDecl, {
  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
})

DEF_TRAVERSE_DECL(UsingShadowDecl, {})

DEF_TRAVERSE_DECL(OMPThreadPrivateDecl, {
  for (auto *I : D->varlists()) {
    TRY_TO(TraverseStmt(I));
  }
})

// A helper method for TemplateDecl's children.
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateParameterListHelper(
    TemplateParameterList *TPL) {
  if (TPL) {
    for (TemplateParameterList::iterator I = TPL->begin(), E = TPL->end();
         I != E; ++I) {
      TRY_TO(TraverseDecl(*I));
    }
  }
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateInstantiations(
    ClassTemplateDecl *D) {
  for (auto *SD : D->specializations()) {
    for (auto *RD : SD->redecls()) {
      // We don't want to visit injected-class-names in this traversal.
      if (cast<CXXRecordDecl>(RD)->isInjectedClassName())
        continue;

      switch (
          cast<ClassTemplateSpecializationDecl>(RD)->getSpecializationKind()) {
      // Visit the implicit instantiations with the requested pattern.
      case TSK_Undeclared:
      case TSK_ImplicitInstantiation:
        TRY_TO(TraverseDecl(RD));
        break;

      // We don't need to do anything on an explicit instantiation
      // or explicit specialization because there will be an explicit
      // node for it elsewhere.
      case TSK_ExplicitInstantiationDeclaration:
      case TSK_ExplicitInstantiationDefinition:
      case TSK_ExplicitSpecialization:
        break;
      }
    }
  }

  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateInstantiations(
    VarTemplateDecl *D) {
  for (auto *SD : D->specializations()) {
    for (auto *RD : SD->redecls()) {
      switch (
          cast<VarTemplateSpecializationDecl>(RD)->getSpecializationKind()) {
      case TSK_Undeclared:
      case TSK_ImplicitInstantiation:
        TRY_TO(TraverseDecl(RD));
        break;

      case TSK_ExplicitInstantiationDeclaration:
      case TSK_ExplicitInstantiationDefinition:
      case TSK_ExplicitSpecialization:
        break;
      }
    }
  }

  return true;
}

// A helper method for traversing the instantiations of a
// function while skipping its specializations.
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateInstantiations(
    FunctionTemplateDecl *D) {
  for (auto *FD : D->specializations()) {
    for (auto *RD : FD->redecls()) {
      switch (RD->getTemplateSpecializationKind()) {
      case TSK_Undeclared:
      case TSK_ImplicitInstantiation:
        // We don't know what kind of FunctionDecl this is.
        TRY_TO(TraverseDecl(RD));
        break;

      // FIXME: For now traverse explicit instantiations here. Change that
      // once they are represented as dedicated nodes in the AST.
      case TSK_ExplicitInstantiationDeclaration:
      case TSK_ExplicitInstantiationDefinition:
        TRY_TO(TraverseDecl(RD));
        break;

      case TSK_ExplicitSpecialization:
        break;
      }
    }
  }

  return true;
}

// This macro unifies the traversal of class, variable and function
// template declarations.
#define DEF_TRAVERSE_TMPL_DECL(TMPLDECLKIND)                                   \
  DEF_TRAVERSE_DECL(TMPLDECLKIND##TemplateDecl, {                              \
    TRY_TO(TraverseDecl(D->getTemplatedDecl()));                             \
    TRY_TO(TraverseTemplateParameterListHelper(D->getTemplateParameters())); \
                                                                             \
    /* By default, we do not traverse the instantiations of
       class templates since they do not appear in the user code. The
       following code optionally traverses them.

       We only traverse the class instantiations when we see the canonical
       declaration of the template, to ensure we only visit them once. */    \
    if (getDerived().shouldVisitTemplateInstantiations() &&                  \
        D == D->getCanonicalDecl())                                          \
      TRY_TO(TraverseTemplateInstantiations(D));                             \
                                                                             \
    /* Note that getInstantiatedFromMemberTemplate() is just a link
       from a template instantiation back to the template from which
       it was instantiated, and thus should not be traversed. */             \
  })

DEF_TRAVERSE_TMPL_DECL(Class)
DEF_TRAVERSE_TMPL_DECL(Var)
DEF_TRAVERSE_TMPL_DECL(Function)

DEF_TRAVERSE_DECL(TemplateTemplateParmDecl, {
  // D is the "T" in something like
  //   template <template <typename> class T> class container { };
  TRY_TO(TraverseDecl(D->getTemplatedDecl()));
  if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
    TRY_TO(TraverseTemplateArgumentLoc(D->getDefaultArgument()));
  }
  TRY_TO(TraverseTemplateParameterListHelper(D->getTemplateParameters()));
})

DEF_TRAVERSE_DECL(TemplateTypeParmDecl, {
  // D is the "T" in something like "template<typename T> class vector;"
  if (D->getTypeForDecl())
    TRY_TO(TraverseType(QualType(D->getTypeForDecl(), 0)));
  if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited())
    TRY_TO(TraverseTypeLoc(D->getDefaultArgumentInfo()->getTypeLoc()));
})

DEF_TRAVERSE_DECL(TypedefDecl, {
  TRY_TO(TraverseTypeLoc(D->getTypeSourceInfo()->getTypeLoc()));
  // We shouldn't traverse D->getTypeForDecl(); it's a result of
  // declaring the typedef, not something that was written in the
  // source.
})

DEF_TRAVERSE_DECL(TypeAliasDecl, {
  TRY_TO(TraverseTypeLoc(D->getTypeSourceInfo()->getTypeLoc()));
  // We shouldn't traverse D->getTypeForDecl(); it's a result of
  // declaring the type alias, not something that was written in the
  // source.
})

DEF_TRAVERSE_DECL(TypeAliasTemplateDecl, {
  TRY_TO(TraverseDecl(D->getTemplatedDecl()));
  TRY_TO(TraverseTemplateParameterListHelper(D->getTemplateParameters()));
})

DEF_TRAVERSE_DECL(UnresolvedUsingTypenameDecl, {
  // A dependent using declaration which was marked with 'typename'.
  //   template<class T> class A : public B<T> { using typename B<T>::foo; };
  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
  // We shouldn't traverse D->getTypeForDecl(); it's a result of
  // declaring the type, not something that was written in the
  // source.
})

DEF_TRAVERSE_DECL(EnumDecl, {
  if (D->getTypeForDecl())
    TRY_TO(TraverseType(QualType(D->getTypeForDecl(), 0)));

  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
  // The enumerators are already traversed by
  // decls_begin()/decls_end().
})

// Helper methods for RecordDecl and its children.
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseRecordHelper(RecordDecl *D) {
  // We shouldn't traverse D->getTypeForDecl(); it's a result of
  // declaring the type, not something that was written in the source.

  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseCXXRecordHelper(CXXRecordDecl *D) {
  if (!TraverseRecordHelper(D))
    return false;
  if (D->isCompleteDefinition()) {
    for (const auto &I : D->bases()) {
      TRY_TO(TraverseTypeLoc(I.getTypeSourceInfo()->getTypeLoc()));
    }
    // We don't traverse the friends or the conversions, as they are
    // already in decls_begin()/decls_end().
  }
  return true;
}

DEF_TRAVERSE_DECL(RecordDecl, { TRY_TO(TraverseRecordHelper(D)); })

DEF_TRAVERSE_DECL(CXXRecordDecl, { TRY_TO(TraverseCXXRecordHelper(D)); })

#define DEF_TRAVERSE_TMPL_SPEC_DECL(TMPLDECLKIND)                              \
  DEF_TRAVERSE_DECL(TMPLDECLKIND##TemplateSpecializationDecl, {                \
    /* For implicit instantiations ("set<int> x;"), we don't want to           \
       recurse at all, since the instatiated template isn't written in         \
       the source code anywhere.  (Note the instatiated *type* --              \
       set<int> -- is written, and will still get a callback of                \
       TemplateSpecializationType).  For explicit instantiations               \
       ("template set<int>;"), we do need a callback, since this               \
       is the only callback that's made for this instantiation.                \
       We use getTypeAsWritten() to distinguish. */                            \
    if (TypeSourceInfo *TSI = D->getTypeAsWritten())                           \
      TRY_TO(TraverseTypeLoc(TSI->getTypeLoc()));                              \
                                                                               \
    if (!getDerived().shouldVisitTemplateInstantiations() &&                   \
        D->getTemplateSpecializationKind() != TSK_ExplicitSpecialization)      \
      /* Returning from here skips traversing the                              \
         declaration context of the *TemplateSpecializationDecl                \
         (embedded in the DEF_TRAVERSE_DECL() macro)                           \
         which contains the instantiated members of the template. */           \
      return true;                                                             \
  })

DEF_TRAVERSE_TMPL_SPEC_DECL(Class)
DEF_TRAVERSE_TMPL_SPEC_DECL(Var)

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseTemplateArgumentLocsHelper(
    const TemplateArgumentLoc *TAL, unsigned Count) {
  for (unsigned I = 0; I < Count; ++I) {
    TRY_TO(TraverseTemplateArgumentLoc(TAL[I]));
  }
  return true;
}

#define DEF_TRAVERSE_TMPL_PART_SPEC_DECL(TMPLDECLKIND, DECLKIND)               \
  DEF_TRAVERSE_DECL(TMPLDECLKIND##TemplatePartialSpecializationDecl, {         \
    /* The partial specialization. */                                        \
    if (TemplateParameterList *TPL = D->getTemplateParameters()) {           \
      for (TemplateParameterList::iterator I = TPL->begin(), E = TPL->end(); \
           I != E; ++I) {                                                    \
        TRY_TO(TraverseDecl(*I));                                            \
      }                                                                      \
    }                                                                        \
    /* The args that remains unspecialized. */                               \
    TRY_TO(TraverseTemplateArgumentLocsHelper(                               \
                      D->getTemplateArgsAsWritten()->getTemplateArgs(),      \
                      D->getTemplateArgsAsWritten()->NumTemplateArgs));      \
                                                                             \
    /* Don't need the *TemplatePartialSpecializationHelper, even
       though that's our parent class -- we already visit all the
       template args here. */                                                \
    TRY_TO(Traverse##DECLKIND##Helper(D));                                   \
                                                                             \
    /* Instantiations will have been visited with the primary template. */   \
  })

DEF_TRAVERSE_TMPL_PART_SPEC_DECL(Class, CXXRecord)
DEF_TRAVERSE_TMPL_PART_SPEC_DECL(Var, Var)

DEF_TRAVERSE_DECL(EnumConstantDecl, { TRY_TO(TraverseStmt(D->getInitExpr())); })

DEF_TRAVERSE_DECL(UnresolvedUsingValueDecl, {
  // Like UnresolvedUsingTypenameDecl, but without the 'typename':
  //    template <class T> Class A : public Base<T> { using Base<T>::foo; };
  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(D->getNameInfo()));
})

DEF_TRAVERSE_DECL(IndirectFieldDecl, {})

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseDeclaratorHelper(DeclaratorDecl *D) {
  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
  if (D->getTypeSourceInfo())
    TRY_TO(TraverseTypeLoc(D->getTypeSourceInfo()->getTypeLoc()));
  else
    TRY_TO(TraverseType(D->getType()));
  return true;
}

DEF_TRAVERSE_DECL(MSPropertyDecl, { TRY_TO(TraverseDeclaratorHelper(D)); })

DEF_TRAVERSE_DECL(FieldDecl, {
  TRY_TO(TraverseDeclaratorHelper(D));
  if (D->isBitField())
    TRY_TO(TraverseStmt(D->getBitWidth()));
  else if (D->hasInClassInitializer())
    TRY_TO(TraverseStmt(D->getInClassInitializer()));
})

DEF_TRAVERSE_DECL(ObjCAtDefsFieldDecl, {
  TRY_TO(TraverseDeclaratorHelper(D));
  if (D->isBitField())
    TRY_TO(TraverseStmt(D->getBitWidth()));
  // FIXME: implement the rest.
})

DEF_TRAVERSE_DECL(ObjCIvarDecl, {
  TRY_TO(TraverseDeclaratorHelper(D));
  if (D->isBitField())
    TRY_TO(TraverseStmt(D->getBitWidth()));
  // FIXME: implement the rest.
})

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseFunctionHelper(FunctionDecl *D) {
  TRY_TO(TraverseNestedNameSpecifierLoc(D->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(D->getNameInfo()));

  // If we're an explicit template specialization, iterate over the
  // template args that were explicitly specified.  If we were doing
  // this in typing order, we'd do it between the return type and
  // the function args, but both are handled by the FunctionTypeLoc
  // above, so we have to choose one side.  I've decided to do before.
  if (const FunctionTemplateSpecializationInfo *FTSI =
          D->getTemplateSpecializationInfo()) {
    if (FTSI->getTemplateSpecializationKind() != TSK_Undeclared &&
        FTSI->getTemplateSpecializationKind() != TSK_ImplicitInstantiation) {
      // A specialization might not have explicit template arguments if it has
      // a templated return type and concrete arguments.
      if (const ASTTemplateArgumentListInfo *TALI =
              FTSI->TemplateArgumentsAsWritten) {
        TRY_TO(TraverseTemplateArgumentLocsHelper(TALI->getTemplateArgs(),
                                                  TALI->NumTemplateArgs));
      }
    }
  }

  // Visit the function type itself, which can be either
  // FunctionNoProtoType or FunctionProtoType, or a typedef.  This
  // also covers the return type and the function parameters,
  // including exception specifications.
  if (TypeSourceInfo *TSI = D->getTypeSourceInfo()) {
    TRY_TO(TraverseTypeLoc(TSI->getTypeLoc()));
  } else if (getDerived().shouldVisitImplicitCode()) {
    // Visit parameter variable declarations of the implicit function
    // if the traverser is visiting implicit code. Parameter variable
    // declarations do not have valid TypeSourceInfo, so to visit them
    // we need to traverse the declarations explicitly.
    for (FunctionDecl::param_const_iterator I = D->param_begin(),
                                            E = D->param_end();
         I != E; ++I)
      TRY_TO(TraverseDecl(*I));
  }

  if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(D)) {
    // Constructor initializers.
    for (auto *I : Ctor->inits()) {
      TRY_TO(TraverseConstructorInitializer(I));
    }
  }

  if (D->isThisDeclarationADefinition()) {
    TRY_TO(TraverseStmt(D->getBody())); // Function body.
  }
  return true;
}

DEF_TRAVERSE_DECL(FunctionDecl, {
  // We skip decls_begin/decls_end, which are already covered by
  // TraverseFunctionHelper().
  return TraverseFunctionHelper(D);
})

DEF_TRAVERSE_DECL(CXXMethodDecl, {
  // We skip decls_begin/decls_end, which are already covered by
  // TraverseFunctionHelper().
  return TraverseFunctionHelper(D);
})

DEF_TRAVERSE_DECL(CXXConstructorDecl, {
  // We skip decls_begin/decls_end, which are already covered by
  // TraverseFunctionHelper().
  return TraverseFunctionHelper(D);
})

// CXXConversionDecl is the declaration of a type conversion operator.
// It's not a cast expression.
DEF_TRAVERSE_DECL(CXXConversionDecl, {
  // We skip decls_begin/decls_end, which are already covered by
  // TraverseFunctionHelper().
  return TraverseFunctionHelper(D);
})

DEF_TRAVERSE_DECL(CXXDestructorDecl, {
  // We skip decls_begin/decls_end, which are already covered by
  // TraverseFunctionHelper().
  return TraverseFunctionHelper(D);
})

template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseVarHelper(VarDecl *D) {
  TRY_TO(TraverseDeclaratorHelper(D));
  // Default params are taken care of when we traverse the ParmVarDecl.
  if (!isa<ParmVarDecl>(D) &&
      (!D->isCXXForRangeDecl() || getDerived().shouldVisitImplicitCode()))
    TRY_TO(TraverseStmt(D->getInit()));
  return true;
}

DEF_TRAVERSE_DECL(VarDecl, { TRY_TO(TraverseVarHelper(D)); })

DEF_TRAVERSE_DECL(ImplicitParamDecl, { TRY_TO(TraverseVarHelper(D)); })

DEF_TRAVERSE_DECL(NonTypeTemplateParmDecl, {
  // A non-type template parameter, e.g. "S" in template<int S> class Foo ...
  TRY_TO(TraverseDeclaratorHelper(D));
  if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited())
    TRY_TO(TraverseStmt(D->getDefaultArgument()));
})

DEF_TRAVERSE_DECL(ParmVarDecl, {
  TRY_TO(TraverseVarHelper(D));

  if (D->hasDefaultArg() && D->hasUninstantiatedDefaultArg() &&
      !D->hasUnparsedDefaultArg())
    TRY_TO(TraverseStmt(D->getUninstantiatedDefaultArg()));

  if (D->hasDefaultArg() && !D->hasUninstantiatedDefaultArg() &&
      !D->hasUnparsedDefaultArg())
    TRY_TO(TraverseStmt(D->getDefaultArg()));
})

#undef DEF_TRAVERSE_DECL

// ----------------- Stmt traversal -----------------
//
// For stmts, we automate (in the DEF_TRAVERSE_STMT macro) iterating
// over the children defined in children() (every stmt defines these,
// though sometimes the range is empty).  Each individual Traverse*
// method only needs to worry about children other than those.  To see
// what children() does for a given class, see, e.g.,
//   http://clang.llvm.org/doxygen/Stmt_8cpp_source.html

// This macro makes available a variable S, the passed-in stmt.
#define DEF_TRAVERSE_STMT(STMT, CODE)                                          \
  template <typename Derived>                                                  \
  bool RecursiveASTVisitor<Derived>::Traverse##STMT(STMT *S) {                 \
    TRY_TO(WalkUpFrom##STMT(S));                                               \
    { CODE; }                                                                  \
    for (Stmt::child_range range = S->children(); range; ++range) {            \
      TRY_TO(TraverseStmt(*range));                                            \
    }                                                                          \
    return true;                                                               \
  }

DEF_TRAVERSE_STMT(GCCAsmStmt, {
  TRY_TO(TraverseStmt(S->getAsmString()));
  for (unsigned I = 0, E = S->getNumInputs(); I < E; ++I) {
    TRY_TO(TraverseStmt(S->getInputConstraintLiteral(I)));
  }
  for (unsigned I = 0, E = S->getNumOutputs(); I < E; ++I) {
    TRY_TO(TraverseStmt(S->getOutputConstraintLiteral(I)));
  }
  for (unsigned I = 0, E = S->getNumClobbers(); I < E; ++I) {
    TRY_TO(TraverseStmt(S->getClobberStringLiteral(I)));
  }
  // children() iterates over inputExpr and outputExpr.
})

DEF_TRAVERSE_STMT(
    MSAsmStmt,
    {// FIXME: MS Asm doesn't currently parse Constraints, Clobbers, etc.  Once
     // added this needs to be implemented.
    })

DEF_TRAVERSE_STMT(CXXCatchStmt, {
  TRY_TO(TraverseDecl(S->getExceptionDecl()));
  // children() iterates over the handler block.
})

DEF_TRAVERSE_STMT(DeclStmt, {
  for (auto *I : S->decls()) {
    TRY_TO(TraverseDecl(I));
  }
  // Suppress the default iteration over children() by
  // returning.  Here's why: A DeclStmt looks like 'type var [=
  // initializer]'.  The decls above already traverse over the
  // initializers, so we don't have to do it again (which
  // children() would do).
  return true;
})

// These non-expr stmts (most of them), do not need any action except
// iterating over the children.
DEF_TRAVERSE_STMT(BreakStmt, {})
DEF_TRAVERSE_STMT(CXXTryStmt, {})
DEF_TRAVERSE_STMT(CaseStmt, {})
DEF_TRAVERSE_STMT(CompoundStmt, {})
DEF_TRAVERSE_STMT(ContinueStmt, {})
DEF_TRAVERSE_STMT(DefaultStmt, {})
DEF_TRAVERSE_STMT(DoStmt, {})
DEF_TRAVERSE_STMT(ForStmt, {})
DEF_TRAVERSE_STMT(GotoStmt, {})
DEF_TRAVERSE_STMT(IfStmt, {})
DEF_TRAVERSE_STMT(IndirectGotoStmt, {})
DEF_TRAVERSE_STMT(LabelStmt, {})
DEF_TRAVERSE_STMT(AttributedStmt, {})
DEF_TRAVERSE_STMT(NullStmt, {})
DEF_TRAVERSE_STMT(ObjCAtCatchStmt, {})
DEF_TRAVERSE_STMT(ObjCAtFinallyStmt, {})
DEF_TRAVERSE_STMT(ObjCAtSynchronizedStmt, {})
DEF_TRAVERSE_STMT(ObjCAtThrowStmt, {})
DEF_TRAVERSE_STMT(ObjCAtTryStmt, {})
DEF_TRAVERSE_STMT(ObjCForCollectionStmt, {})
DEF_TRAVERSE_STMT(ObjCAutoreleasePoolStmt, {})
DEF_TRAVERSE_STMT(CXXForRangeStmt, {
  if (!getDerived().shouldVisitImplicitCode()) {
    TRY_TO(TraverseStmt(S->getLoopVarStmt()));
    TRY_TO(TraverseStmt(S->getRangeInit()));
    TRY_TO(TraverseStmt(S->getBody()));
    // Visit everything else only if shouldVisitImplicitCode().
    return true;
  }
})
DEF_TRAVERSE_STMT(MSDependentExistsStmt, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(S->getNameInfo()));
})
DEF_TRAVERSE_STMT(ReturnStmt, {})
DEF_TRAVERSE_STMT(SwitchStmt, {})
DEF_TRAVERSE_STMT(WhileStmt, {})

DEF_TRAVERSE_STMT(CXXDependentScopeMemberExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(S->getMemberNameInfo()));
  if (S->hasExplicitTemplateArgs()) {
    TRY_TO(TraverseTemplateArgumentLocsHelper(S->getTemplateArgs(),
                                              S->getNumTemplateArgs()));
  }
})

DEF_TRAVERSE_STMT(DeclRefExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(S->getNameInfo()));
  TRY_TO(TraverseTemplateArgumentLocsHelper(S->getTemplateArgs(),
                                            S->getNumTemplateArgs()));
})

DEF_TRAVERSE_STMT(DependentScopeDeclRefExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(S->getNameInfo()));
  if (S->hasExplicitTemplateArgs()) {
    TRY_TO(TraverseTemplateArgumentLocsHelper(
        S->getExplicitTemplateArgs().getTemplateArgs(),
        S->getNumTemplateArgs()));
  }
})

DEF_TRAVERSE_STMT(MemberExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  TRY_TO(TraverseDeclarationNameInfo(S->getMemberNameInfo()));
  TRY_TO(TraverseTemplateArgumentLocsHelper(S->getTemplateArgs(),
                                            S->getNumTemplateArgs()));
})

DEF_TRAVERSE_STMT(
    ImplicitCastExpr,
    {// We don't traverse the cast type, as it's not written in the
     // source code.
    })

DEF_TRAVERSE_STMT(CStyleCastExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeInfoAsWritten()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXFunctionalCastExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeInfoAsWritten()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXConstCastExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeInfoAsWritten()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXDynamicCastExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeInfoAsWritten()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXReinterpretCastExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeInfoAsWritten()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXStaticCastExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeInfoAsWritten()->getTypeLoc()));
})

// InitListExpr is a tricky one, because we want to do all our work on
// the syntactic form of the listexpr, but this method takes the
// semantic form by default.  We can't use the macro helper because it
// calls WalkUp*() on the semantic form, before our code can convert
// to the syntactic form.
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseInitListExpr(InitListExpr *S) {
  if (InitListExpr *Syn = S->getSyntacticForm())
    S = Syn;
  TRY_TO(WalkUpFromInitListExpr(S));
  // All we need are the default actions.  FIXME: use a helper function.
  for (Stmt::child_range range = S->children(); range; ++range) {
    TRY_TO(TraverseStmt(*range));
  }
  return true;
}

// GenericSelectionExpr is a special case because the types and expressions
// are interleaved.  We also need to watch out for null types (default
// generic associations).
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseGenericSelectionExpr(
    GenericSelectionExpr *S) {
  TRY_TO(WalkUpFromGenericSelectionExpr(S));
  TRY_TO(TraverseStmt(S->getControllingExpr()));
  for (unsigned i = 0; i != S->getNumAssocs(); ++i) {
    if (TypeSourceInfo *TS = S->getAssocTypeSourceInfo(i))
      TRY_TO(TraverseTypeLoc(TS->getTypeLoc()));
    TRY_TO(TraverseStmt(S->getAssocExpr(i)));
  }
  return true;
}

// PseudoObjectExpr is a special case because of the wierdness with
// syntactic expressions and opaque values.
template <typename Derived>
bool
RecursiveASTVisitor<Derived>::TraversePseudoObjectExpr(PseudoObjectExpr *S) {
  TRY_TO(WalkUpFromPseudoObjectExpr(S));
  TRY_TO(TraverseStmt(S->getSyntacticForm()));
  for (PseudoObjectExpr::semantics_iterator i = S->semantics_begin(),
                                            e = S->semantics_end();
       i != e; ++i) {
    Expr *sub = *i;
    if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(sub))
      sub = OVE->getSourceExpr();
    TRY_TO(TraverseStmt(sub));
  }
  return true;
}

DEF_TRAVERSE_STMT(CXXScalarValueInitExpr, {
  // This is called for code like 'return T()' where T is a built-in
  // (i.e. non-class) type.
  TRY_TO(TraverseTypeLoc(S->getTypeSourceInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXNewExpr, {
  // The child-iterator will pick up the other arguments.
  TRY_TO(TraverseTypeLoc(S->getAllocatedTypeSourceInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(OffsetOfExpr, {
  // The child-iterator will pick up the expression representing
  // the field.
  // FIMXE: for code like offsetof(Foo, a.b.c), should we get
  // making a MemberExpr callbacks for Foo.a, Foo.a.b, and Foo.a.b.c?
  TRY_TO(TraverseTypeLoc(S->getTypeSourceInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(UnaryExprOrTypeTraitExpr, {
  // The child-iterator will pick up the arg if it's an expression,
  // but not if it's a type.
  if (S->isArgumentType())
    TRY_TO(TraverseTypeLoc(S->getArgumentTypeInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXTypeidExpr, {
  // The child-iterator will pick up the arg if it's an expression,
  // but not if it's a type.
  if (S->isTypeOperand())
    TRY_TO(TraverseTypeLoc(S->getTypeOperandSourceInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(MSPropertyRefExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
})

DEF_TRAVERSE_STMT(CXXUuidofExpr, {
  // The child-iterator will pick up the arg if it's an expression,
  // but not if it's a type.
  if (S->isTypeOperand())
    TRY_TO(TraverseTypeLoc(S->getTypeOperandSourceInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(TypeTraitExpr, {
  for (unsigned I = 0, N = S->getNumArgs(); I != N; ++I)
    TRY_TO(TraverseTypeLoc(S->getArg(I)->getTypeLoc()));
})

DEF_TRAVERSE_STMT(ArrayTypeTraitExpr, {
  TRY_TO(TraverseTypeLoc(S->getQueriedTypeSourceInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(ExpressionTraitExpr,
                  { TRY_TO(TraverseStmt(S->getQueriedExpression())); })

DEF_TRAVERSE_STMT(VAArgExpr, {
  // The child-iterator will pick up the expression argument.
  TRY_TO(TraverseTypeLoc(S->getWrittenTypeInfo()->getTypeLoc()));
})

DEF_TRAVERSE_STMT(CXXTemporaryObjectExpr, {
  // This is called for code like 'return T()' where T is a class type.
  TRY_TO(TraverseTypeLoc(S->getTypeSourceInfo()->getTypeLoc()));
})

// Walk only the visible parts of lambda expressions.
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseLambdaExpr(LambdaExpr *S) {
  TRY_TO(WalkUpFromLambdaExpr(S));

  for (LambdaExpr::capture_iterator C = S->explicit_capture_begin(),
                                    CEnd = S->explicit_capture_end();
       C != CEnd; ++C) {
    TRY_TO(TraverseLambdaCapture(S, C));
  }

  if (S->hasExplicitParameters() || S->hasExplicitResultType()) {
    TypeLoc TL = S->getCallOperator()->getTypeSourceInfo()->getTypeLoc();
    if (S->hasExplicitParameters() && S->hasExplicitResultType()) {
      // Visit the whole type.
      TRY_TO(TraverseTypeLoc(TL));
    } else if (FunctionProtoTypeLoc Proto = TL.getAs<FunctionProtoTypeLoc>()) {
      if (S->hasExplicitParameters()) {
        // Visit parameters.
        for (unsigned I = 0, N = Proto.getNumParams(); I != N; ++I) {
          TRY_TO(TraverseDecl(Proto.getParam(I)));
        }
      } else {
        TRY_TO(TraverseTypeLoc(Proto.getReturnLoc()));
      }
    }
  }

  TRY_TO(TraverseLambdaBody(S));
  return true;
}

DEF_TRAVERSE_STMT(CXXUnresolvedConstructExpr, {
  // This is called for code like 'T()', where T is a template argument.
  TRY_TO(TraverseTypeLoc(S->getTypeSourceInfo()->getTypeLoc()));
})

// These expressions all might take explicit template arguments.
// We traverse those if so.  FIXME: implement these.
DEF_TRAVERSE_STMT(CXXConstructExpr, {})
DEF_TRAVERSE_STMT(CallExpr, {})
DEF_TRAVERSE_STMT(CXXMemberCallExpr, {})

// These exprs (most of them), do not need any action except iterating
// over the children.
DEF_TRAVERSE_STMT(AddrLabelExpr, {})
DEF_TRAVERSE_STMT(ArraySubscriptExpr, {})
DEF_TRAVERSE_STMT(BlockExpr, {
  TRY_TO(TraverseDecl(S->getBlockDecl()));
  return true; // no child statements to loop through.
})
DEF_TRAVERSE_STMT(ChooseExpr, {})
DEF_TRAVERSE_STMT(CompoundLiteralExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeSourceInfo()->getTypeLoc()));
})
DEF_TRAVERSE_STMT(CXXBindTemporaryExpr, {})
DEF_TRAVERSE_STMT(CXXBoolLiteralExpr, {})
DEF_TRAVERSE_STMT(CXXDefaultArgExpr, {})
DEF_TRAVERSE_STMT(CXXDefaultInitExpr, {})
DEF_TRAVERSE_STMT(CXXDeleteExpr, {})
DEF_TRAVERSE_STMT(ExprWithCleanups, {})
DEF_TRAVERSE_STMT(CXXNullPtrLiteralExpr, {})
DEF_TRAVERSE_STMT(CXXStdInitializerListExpr, {})
DEF_TRAVERSE_STMT(CXXPseudoDestructorExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  if (TypeSourceInfo *ScopeInfo = S->getScopeTypeInfo())
    TRY_TO(TraverseTypeLoc(ScopeInfo->getTypeLoc()));
  if (TypeSourceInfo *DestroyedTypeInfo = S->getDestroyedTypeInfo())
    TRY_TO(TraverseTypeLoc(DestroyedTypeInfo->getTypeLoc()));
})
DEF_TRAVERSE_STMT(CXXThisExpr, {})
DEF_TRAVERSE_STMT(CXXThrowExpr, {})
DEF_TRAVERSE_STMT(UserDefinedLiteral, {})
DEF_TRAVERSE_STMT(DesignatedInitExpr, {})
DEF_TRAVERSE_STMT(ExtVectorElementExpr, {})
DEF_TRAVERSE_STMT(GNUNullExpr, {})
DEF_TRAVERSE_STMT(ImplicitValueInitExpr, {})
DEF_TRAVERSE_STMT(ObjCBoolLiteralExpr, {})
DEF_TRAVERSE_STMT(ObjCEncodeExpr, {
  if (TypeSourceInfo *TInfo = S->getEncodedTypeSourceInfo())
    TRY_TO(TraverseTypeLoc(TInfo->getTypeLoc()));
})
DEF_TRAVERSE_STMT(ObjCIsaExpr, {})
DEF_TRAVERSE_STMT(ObjCIvarRefExpr, {})
DEF_TRAVERSE_STMT(ObjCMessageExpr, {
  if (TypeSourceInfo *TInfo = S->getClassReceiverTypeInfo())
    TRY_TO(TraverseTypeLoc(TInfo->getTypeLoc()));
})
DEF_TRAVERSE_STMT(ObjCPropertyRefExpr, {})
DEF_TRAVERSE_STMT(ObjCSubscriptRefExpr, {})
DEF_TRAVERSE_STMT(ObjCProtocolExpr, {})
DEF_TRAVERSE_STMT(ObjCSelectorExpr, {})
DEF_TRAVERSE_STMT(ObjCIndirectCopyRestoreExpr, {})
DEF_TRAVERSE_STMT(ObjCBridgedCastExpr, {
  TRY_TO(TraverseTypeLoc(S->getTypeInfoAsWritten()->getTypeLoc()));
})
DEF_TRAVERSE_STMT(ParenExpr, {})
DEF_TRAVERSE_STMT(ParenListExpr, {})
DEF_TRAVERSE_STMT(PredefinedExpr, {})
DEF_TRAVERSE_STMT(ShuffleVectorExpr, {})
DEF_TRAVERSE_STMT(ConvertVectorExpr, {})
DEF_TRAVERSE_STMT(StmtExpr, {})
DEF_TRAVERSE_STMT(UnresolvedLookupExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  if (S->hasExplicitTemplateArgs()) {
    TRY_TO(TraverseTemplateArgumentLocsHelper(S->getTemplateArgs(),
                                              S->getNumTemplateArgs()));
  }
})

DEF_TRAVERSE_STMT(UnresolvedMemberExpr, {
  TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
  if (S->hasExplicitTemplateArgs()) {
    TRY_TO(TraverseTemplateArgumentLocsHelper(S->getTemplateArgs(),
                                              S->getNumTemplateArgs()));
  }
})

DEF_TRAVERSE_STMT(SEHTryStmt, {})
DEF_TRAVERSE_STMT(SEHExceptStmt, {})
DEF_TRAVERSE_STMT(SEHFinallyStmt, {})
DEF_TRAVERSE_STMT(CapturedStmt, { TRY_TO(TraverseDecl(S->getCapturedDecl())); })

DEF_TRAVERSE_STMT(CXXOperatorCallExpr, {})
DEF_TRAVERSE_STMT(OpaqueValueExpr, {})
DEF_TRAVERSE_STMT(CUDAKernelCallExpr, {})

// These operators (all of them) do not need any action except
// iterating over the children.
DEF_TRAVERSE_STMT(BinaryConditionalOperator, {})
DEF_TRAVERSE_STMT(ConditionalOperator, {})
DEF_TRAVERSE_STMT(UnaryOperator, {})
DEF_TRAVERSE_STMT(BinaryOperator, {})
DEF_TRAVERSE_STMT(CompoundAssignOperator, {})
DEF_TRAVERSE_STMT(CXXNoexceptExpr, {})
DEF_TRAVERSE_STMT(PackExpansionExpr, {})
DEF_TRAVERSE_STMT(SizeOfPackExpr, {})
DEF_TRAVERSE_STMT(SubstNonTypeTemplateParmPackExpr, {})
DEF_TRAVERSE_STMT(SubstNonTypeTemplateParmExpr, {})
DEF_TRAVERSE_STMT(FunctionParmPackExpr, {})
DEF_TRAVERSE_STMT(MaterializeTemporaryExpr, {})
DEF_TRAVERSE_STMT(AtomicExpr, {})

// These literals (all of them) do not need any action.
DEF_TRAVERSE_STMT(IntegerLiteral, {})
DEF_TRAVERSE_STMT(CharacterLiteral, {})
DEF_TRAVERSE_STMT(FloatingLiteral, {})
DEF_TRAVERSE_STMT(ImaginaryLiteral, {})
DEF_TRAVERSE_STMT(StringLiteral, {})
DEF_TRAVERSE_STMT(ObjCStringLiteral, {})
DEF_TRAVERSE_STMT(ObjCBoxedExpr, {})
DEF_TRAVERSE_STMT(ObjCArrayLiteral, {})
DEF_TRAVERSE_STMT(ObjCDictionaryLiteral, {})

// Traverse OpenCL: AsType, Convert.
DEF_TRAVERSE_STMT(AsTypeExpr, {})

// OpenMP directives.
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseOMPExecutableDirective(
    OMPExecutableDirective *S) {
  ArrayRef<OMPClause *> Clauses = S->clauses();
  for (ArrayRef<OMPClause *>::iterator I = Clauses.begin(), E = Clauses.end();
       I != E; ++I)
    if (!TraverseOMPClause(*I))
      return false;
  return true;
}

DEF_TRAVERSE_STMT(OMPParallelDirective, {
  if (!TraverseOMPExecutableDirective(S))
    return false;
})

DEF_TRAVERSE_STMT(OMPSimdDirective, {
  if (!TraverseOMPExecutableDirective(S))
    return false;
})

// OpenMP clauses.
template <typename Derived>
bool RecursiveASTVisitor<Derived>::TraverseOMPClause(OMPClause *C) {
  if (!C)
    return true;
  switch (C->getClauseKind()) {
#define OPENMP_CLAUSE(Name, Class)                                             \
  case OMPC_##Name:                                                            \
    return getDerived().Visit##Class(static_cast<Class *>(C));
#include "clang/Basic/OpenMPKinds.def"
  default:
    break;
  }
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPIfClause(OMPIfClause *C) {
  TraverseStmt(C->getCondition());
  return true;
}

template <typename Derived>
bool
RecursiveASTVisitor<Derived>::VisitOMPNumThreadsClause(OMPNumThreadsClause *C) {
  TraverseStmt(C->getNumThreads());
  return true;
}

template<typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPSafelenClause(OMPSafelenClause *C) {
  TraverseStmt(C->getSafelen());
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPCollapseClause(OMPCollapseClause *C) {
  TraverseStmt(C->getNumForLoops());
  return true;
}

template<typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPDefaultClause(OMPDefaultClause *C) {
  return true;
}

template <typename Derived>
bool
RecursiveASTVisitor<Derived>::VisitOMPProcBindClause(OMPProcBindClause *C) {
  return true;
}

template <typename Derived>
template <typename T>
void RecursiveASTVisitor<Derived>::VisitOMPClauseList(T *Node) {
  for (auto *I : Node->varlists())
    TraverseStmt(I);
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPPrivateClause(OMPPrivateClause *C) {
  VisitOMPClauseList(C);
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPFirstprivateClause(
    OMPFirstprivateClause *C) {
  VisitOMPClauseList(C);
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPSharedClause(OMPSharedClause *C) {
  VisitOMPClauseList(C);
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPLinearClause(OMPLinearClause *C) {
  VisitOMPClauseList(C);
  TraverseStmt(C->getStep());
  return true;
}

template <typename Derived>
bool RecursiveASTVisitor<Derived>::VisitOMPCopyinClause(OMPCopyinClause *C) {
  VisitOMPClauseList(C);
  return true;
}

// FIXME: look at the following tricky-seeming exprs to see if we
// need to recurse on anything.  These are ones that have methods
// returning decls or qualtypes or nestednamespecifier -- though I'm
// not sure if they own them -- or just seemed very complicated, or
// had lots of sub-types to explore.
//
// VisitOverloadExpr and its children: recurse on template args? etc?

// FIXME: go through all the stmts and exprs again, and see which of them
// create new types, and recurse on the types (TypeLocs?) of those.
// Candidates:
//
//    http://clang.llvm.org/doxygen/classclang_1_1CXXTypeidExpr.html
//    http://clang.llvm.org/doxygen/classclang_1_1UnaryExprOrTypeTraitExpr.html
//    http://clang.llvm.org/doxygen/classclang_1_1TypesCompatibleExpr.html
//    Every class that has getQualifier.

#undef DEF_TRAVERSE_STMT

#undef TRY_TO

} // end namespace clang

#endif // LLVM_CLANG_AST_RECURSIVEASTVISITOR_H