[libcxxabi] r309340 - [demangler] Use an AST to represent demangled names

Kostya Serebryany via cfe-commits cfe-commits at lists.llvm.org
Fri Jul 28 10:06:44 PDT 2017


Erik,
A bunch of old bugs reported in this code by OSS-Fuzz got auto-closed
today, thanks!

Also a few new bugs got opened tonight, most likely caused by this patch.
You are auto-CC-ed.
I would start from
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2767

Crash Type: Null-dereference READ
Crash Address: 0x000000000008
Crash State:
  __cxxabiv1::parse_nested_name
  __cxxabiv1::parse_name
  __cxxabiv1::parse_local_name


Also, you have the access to all inputs generated by the demangler
fuzzer in a few months of fuzzing.
You can use that corpus for local testing, and I would also encourage
you to add the corpus to the public LLVM bots.

--kcc



On Thu, Jul 27, 2017 at 5:43 PM, Erik Pilkington via cfe-commits <
cfe-commits at lists.llvm.org> wrote:

> Author: epilk
> Date: Thu Jul 27 17:43:49 2017
> New Revision: 309340
>
> URL: http://llvm.org/viewvc/llvm-project?rev=309340&view=rev
> Log:
> [demangler] Use an AST to represent demangled names
>
> The demangler now demangles by producing an AST, then traverses that
> AST to produce a demangled name. This is done for performance reasons,
> now the demangler doesn't manuiplate std::strings, which hurt
> performance and caused string operations to be inlined into the
> parser, leading to large code size and stack usage.
>
> Differential revision: https://reviews.llvm.org/D35159
>
> Modified:
>     libcxxabi/trunk/src/cxa_demangle.cpp
>     libcxxabi/trunk/test/test_demangle.pass.cpp
>
> Modified: libcxxabi/trunk/src/cxa_demangle.cpp
> URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/
> cxa_demangle.cpp?rev=309340&r1=309339&r2=309340&view=diff
> ============================================================
> ==================
> --- libcxxabi/trunk/src/cxa_demangle.cpp (original)
> +++ libcxxabi/trunk/src/cxa_demangle.cpp Thu Jul 27 17:43:49 2017
> @@ -13,7 +13,6 @@
>
>  #include <vector>
>  #include <algorithm>
> -#include <string>
>  #include <numeric>
>  #include <cstdlib>
>  #include <cstring>
> @@ -41,6 +40,1370 @@ enum
>      success
>  };
>
> +class StringView {
> +  const char *First;
> +  const char *Last;
> +
> +public:
> +  template <size_t N>
> +  StringView(const char (&Str)[N]) : First(Str), Last(Str + N - 1) {}
> +  StringView(const char *First, const char *Last) : First(First),
> Last(Last) {}
> +  StringView() : First(nullptr), Last(nullptr) {}
> +
> +  StringView substr(size_t From, size_t To) {
> +    if (To >= size())
> +      To = size() - 1;
> +    if (From >= size())
> +      From = size() - 1;
> +    return StringView(First + From, First + To);
> +  }
> +
> +  StringView dropFront(size_t N) const {
> +    if (N >= size())
> +      N = size() - 1;
> +    return StringView(First + N, Last);
> +  }
> +
> +  bool startsWith(StringView Str) const {
> +    if (Str.size() > size())
> +      return false;
> +    return std::equal(Str.begin(), Str.end(), begin());
> +  }
> +
> +  const char &operator[](size_t Idx) const { return *(begin() + Idx); }
> +
> +  const char *begin() const { return First; }
> +  const char *end() const { return Last; }
> +  size_t size() const { return static_cast<size_t>(Last - First); }
> +};
> +
> +bool operator==(const StringView &LHS, const StringView &RHS) {
> +  return LHS.size() == RHS.size() &&
> +         std::equal(LHS.begin(), LHS.end(), RHS.begin());
> +}
> +
> +// Stream that AST nodes write their string representation into after the
> AST
> +// has been parsed.
> +class OutputStream {
> +  char *Buffer;
> +  size_t CurrentPosition;
> +  size_t BufferCapacity;
> +
> +  // Ensure there is at least n more positions in buffer.
> +  void grow(size_t N) {
> +    if (N + CurrentPosition >= BufferCapacity) {
> +      BufferCapacity *= 2;
> +      if (BufferCapacity < N + CurrentPosition)
> +        BufferCapacity = N + CurrentPosition;
> +      Buffer = static_cast<char *>(std::realloc(Buffer, BufferCapacity));
> +    }
> +  }
> +
> +public:
> +  OutputStream(char *StartBuf, size_t Size)
> +      : Buffer(StartBuf), CurrentPosition(0), BufferCapacity(Size) {}
> +
> +  OutputStream &operator+=(StringView R) {
> +    size_t Size = R.size();
> +    if (Size == 0)
> +      return *this;
> +    grow(Size);
> +    memmove(Buffer + CurrentPosition, R.begin(), Size);
> +    CurrentPosition += Size;
> +    return *this;
> +  }
> +
> +  OutputStream &operator+=(char C) {
> +    grow(1);
> +    Buffer[CurrentPosition++] = C;
> +    return *this;
> +  }
> +
> +  // Offset of position in buffer, used for building stream_string_view.
> +  typedef unsigned StreamPosition;
> +
> +  // StringView into a stream, used for caching the ast nodes.
> +  class StreamStringView {
> +    StreamPosition First, Last;
> +
> +    friend class OutputStream;
> +
> +  public:
> +    StreamStringView() : First(0), Last(0) {}
> +
> +    StreamStringView(StreamPosition First, StreamPosition Last)
> +        : First(First), Last(Last) {}
> +
> +    bool empty() const { return First == Last; }
> +  };
> +
> +  OutputStream &operator+=(StreamStringView &s) {
> +    size_t Sz = static_cast<size_t>(s.Last - s.First);
> +    if (Sz == 0)
> +      return *this;
> +    grow(Sz);
> +    memmove(Buffer + CurrentPosition, Buffer + s.First, Sz);
> +    CurrentPosition += Sz;
> +    return *this;
> +  }
> +
> +  StreamPosition getCurrentPosition() const {
> +    return static_cast<StreamPosition>(CurrentPosition);
> +  }
> +
> +  StreamStringView makeStringViewFromPastPosition(StreamPosition Pos) {
> +    return StreamStringView(Pos, getCurrentPosition());
> +  }
> +
> +  char back() const {
> +    return CurrentPosition ? Buffer[CurrentPosition - 1] : '\0';
> +  }
> +
> +  bool empty() const { return CurrentPosition == 0; }
> +
> +  char *getBuffer() { return Buffer; }
> +  char *getBufferEnd() { return Buffer + CurrentPosition - 1; }
> +  size_t getBufferCapacity() { return BufferCapacity; }
> +};
> +
> +// Base class of all AST nodes. The AST is built by the parser, then is
> +// traversed by the printLeft/Right functions to produce a demangled
> string.
> +class Node {
> +public:
> +  enum Kind : unsigned char {
> +    KDotSuffix,
> +    KVendorExtQualType,
> +    KQualType,
> +    KConversionOperatorType,
> +    KPostfixQualifiedType,
> +    KNameType,
> +    KObjCProtoName,
> +    KPointerType,
> +    KLValueReferenceType,
> +    KRValueReferenceType,
> +    KPointerToMemberType,
> +    KArrayType,
> +    KFunctionType,
> +    KTopLevelFunctionDecl,
> +    KFunctionQualType,
> +    KFunctionRefQualType,
> +    KLiteralOperator,
> +    KSpecialName,
> +    KCtorVtableSpecialName,
> +    KQualifiedName,
> +    KEmptyName,
> +    KVectorType,
> +    KTemplateParams,
> +    KNameWithTemplateArgs,
> +    KGlobalQualifiedName,
> +    KStdQualifiedName,
> +    KExpandedSpecialSubstitution,
> +    KSpecialSubstitution,
> +    KCtorDtorName,
> +    KDtorName,
> +    KUnnamedTypeName,
> +    KLambdaTypeName,
> +    KExpr,
> +  };
> +
> +  const Kind K;
> +
> +private:
> +  // If this Node has any RHS part, potentally many Nodes further down.
> +  const unsigned HasRHSComponent : 1;
> +  const unsigned HasFunction : 1;
> +  const unsigned HasArray : 1;
> +
> +public:
> +  Node(Kind K, bool HasRHS = false, bool HasFunction = false,
> +       bool HasArray = false)
> +      : K(K), HasRHSComponent(HasRHS), HasFunction(HasFunction),
> +        HasArray(HasArray) {}
> +
> +  bool hasRHSComponent() const { return HasRHSComponent; }
> +  bool hasArray() const { return HasArray; }
> +  bool hasFunction() const { return HasFunction; }
> +
> +  void print(OutputStream &s) const {
> +    printLeft(s);
> +    if (hasRHSComponent())
> +      printRight(s);
> +  }
> +
> +  // Print the "left" side of this Node into OutputStream.
> +  virtual void printLeft(OutputStream &) const = 0;
> +
> +  // Print the "right". This distinction is necessary to represent C++
> types
> +  // that appear on the RHS of their subtype, such as arrays or functions.
> +  // Since most types don't have such a component, provide a default
> +  // implemenation.
> +  virtual void printRight(OutputStream &) const {}
> +
> +  virtual StringView getBaseName() const { return StringView(); }
> +
> +  // Silence compiler warnings, this dtor will never be called.
> +  virtual ~Node() = default;
> +};
> +
> +class NodeArray {
> +  Node **Elements;
> +  size_t NumElements;
> +
> +public:
> +  NodeArray() : NumElements(0) {}
> +  NodeArray(Node **Elements, size_t NumElements)
> +      : Elements(Elements), NumElements(NumElements) {}
> +
> +  bool empty() const { return NumElements == 0; }
> +  size_t size() const { return NumElements; }
> +
> +  void printWithSeperator(OutputStream &S, StringView Seperator) const {
> +    for (size_t Idx = 0; Idx != NumElements; ++Idx) {
> +      if (Idx)
> +        S += Seperator;
> +      Elements[Idx]->print(S);
> +    }
> +  }
> +};
> +
> +class DotSuffix final : public Node {
> +  const Node *Prefix;
> +  const StringView Suffix;
> +
> +public:
> +  DotSuffix(Node *Prefix, StringView Suffix)
> +      : Node(KDotSuffix), Prefix(Prefix), Suffix(Suffix) {}
> +
> +  void printLeft(OutputStream &s) const override {
> +    Prefix->print(s);
> +    s += " (";
> +    s += Suffix;
> +    s += ")";
> +  }
> +};
> +
> +class VendorExtQualType final : public Node {
> +  const Node *Ext;
> +  const Node *Ty;
> +
> +public:
> +  VendorExtQualType(Node *Ext, Node *Ty)
> +      : Node(KVendorExtQualType), Ext(Ext), Ty(Ty) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    Ext->print(S);
> +    S += " ";
> +    Ty->printLeft(S);
> +  }
> +
> +  void printRight(OutputStream &S) const override { Ty->printRight(S); }
> +};
> +
> +enum Qualifiers {
> +  QualNone = 0,
> +  QualConst = 0x1,
> +  QualVolatile = 0x2,
> +  QualRestrict = 0x4,
> +};
> +
> +void addQualifiers(Qualifiers &Q1, Qualifiers Q2) {
> +  Q1 = static_cast<Qualifiers>(Q1 | Q2);
> +}
> +
> +class QualType : public Node {
> +protected:
> +  const Qualifiers Quals;
> +  const Node *Child;
> +
> +  void printQuals(OutputStream &S) const {
> +    if (Quals & QualConst)
> +      S += " const";
> +    if (Quals & QualVolatile)
> +      S += " volatile";
> +    if (Quals & QualRestrict)
> +      S += " restrict";
> +  }
> +
> +public:
> +  QualType(Node *Child, Qualifiers Quals)
> +      : Node(KQualType, Child->hasRHSComponent(), Child->hasFunction(),
> +             Child->hasArray()),
> +        Quals(Quals), Child(Child) {}
> +
> +  QualType(Node::Kind ChildKind, Node *Child, Qualifiers Quals)
> +      : Node(ChildKind, Child->hasRHSComponent(), Child->hasFunction(),
> +             Child->hasArray()),
> +        Quals(Quals), Child(Child) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    Child->printLeft(S);
> +    printQuals(S);
> +  }
> +
> +  void printRight(OutputStream &S) const override { Child->printRight(S);
> }
> +};
> +
> +class ConversionOperatorType final : public Node {
> +  const Node *Ty;
> +
> +public:
> +  ConversionOperatorType(Node *Ty) : Node(KConversionOperatorType),
> Ty(Ty) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "operator ";
> +    Ty->print(S);
> +  }
> +};
> +
> +class PostfixQualifiedType final : public Node {
> +  const Node *Ty;
> +  const StringView Postfix;
> +
> +public:
> +  PostfixQualifiedType(Node *Ty, StringView Postfix)
> +      : Node(KPostfixQualifiedType), Ty(Ty), Postfix(Postfix) {}
> +
> +  void printLeft(OutputStream &s) const override {
> +    Ty->printLeft(s);
> +    s += Postfix;
> +  }
> +
> +  void printRight(OutputStream &S) const override { Ty->printRight(S); }
> +};
> +
> +class NameType final : public Node {
> +  const StringView Name;
> +
> +public:
> +  NameType(StringView Name) : Node(KNameType), Name(Name) {}
> +
> +  StringView getName() const { return Name; }
> +  StringView getBaseName() const override { return Name; }
> +
> +  void printLeft(OutputStream &s) const override { s += Name; }
> +};
> +
> +class ObjCProtoName : public Node {
> +  Node *Ty;
> +  Node *Protocol;
> +
> +  friend class PointerType;
> +
> +public:
> +  ObjCProtoName(Node *Ty, Node *Protocol)
> +      : Node(KObjCProtoName), Ty(Ty), Protocol(Protocol) {}
> +
> +  bool isObjCObject() const {
> +    return Ty->K == KNameType &&
> +           static_cast<NameType *>(Ty)->getName() == "objc_object";
> +  }
> +
> +  void printLeft(OutputStream &S) const override {
> +    Ty->printLeft(S);
> +    S += "<";
> +    Protocol->printLeft(S);
> +    S += ">";
> +  }
> +};
> +
> +class PointerType final : public Node {
> +  const Node *Pointee;
> +
> +public:
> +  PointerType(Node *Pointee)
> +      : Node(KPointerType, Pointee->hasRHSComponent()), Pointee(Pointee)
> {}
> +
> +  void printLeft(OutputStream &s) const override {
> +    // We rewrite objc_object<SomeProtocol>* into id<SomeProtocol>.
> +    if (Pointee->K != KObjCProtoName ||
> +        !static_cast<const ObjCProtoName *>(Pointee)->isObjCObject()) {
> +      Pointee->printLeft(s);
> +      if (Pointee->hasArray())
> +        s += " ";
> +      if (Pointee->hasArray() || Pointee->hasFunction())
> +        s += "(";
> +      s += "*";
> +    } else {
> +      const auto *objcProto = static_cast<const ObjCProtoName *>(Pointee);
> +      s += "id<";
> +      objcProto->Protocol->print(s);
> +      s += ">";
> +    }
> +  }
> +
> +  void printRight(OutputStream &s) const override {
> +    if (Pointee->K != KObjCProtoName ||
> +        !static_cast<const ObjCProtoName *>(Pointee)->isObjCObject()) {
> +      if (Pointee->hasArray() || Pointee->hasFunction())
> +        s += ")";
> +      Pointee->printRight(s);
> +    }
> +  }
> +};
> +
> +class LValueReferenceType final : public Node {
> +  const Node *Pointee;
> +
> +public:
> +  LValueReferenceType(Node *Pointee)
> +      : Node(KLValueReferenceType, Pointee->hasRHSComponent()),
> +        Pointee(Pointee) {}
> +
> +  void printLeft(OutputStream &s) const override {
> +    Pointee->printLeft(s);
> +    if (Pointee->hasArray())
> +      s += " ";
> +    if (Pointee->hasArray() || Pointee->hasFunction())
> +      s += "(&";
> +    else
> +      s += "&";
> +  }
> +  void printRight(OutputStream &s) const override {
> +    if (Pointee->hasArray() || Pointee->hasFunction())
> +      s += ")";
> +    Pointee->printRight(s);
> +  }
> +};
> +
> +class RValueReferenceType final : public Node {
> +  const Node *Pointee;
> +
> +public:
> +  RValueReferenceType(Node *Pointee)
> +      : Node(KRValueReferenceType, Pointee->hasRHSComponent()),
> +        Pointee(Pointee) {}
> +
> +  void printLeft(OutputStream &s) const override {
> +    Pointee->printLeft(s);
> +    if (Pointee->hasArray())
> +      s += " ";
> +    if (Pointee->hasArray() || Pointee->hasFunction())
> +      s += "(&&";
> +    else
> +      s += "&&";
> +  }
> +
> +  void printRight(OutputStream &s) const override {
> +    if (Pointee->hasArray() || Pointee->hasFunction())
> +      s += ")";
> +    Pointee->printRight(s);
> +  }
> +};
> +
> +class PointerToMemberType final : public Node {
> +  const Node *ClassType;
> +  const Node *MemberType;
> +
> +public:
> +  PointerToMemberType(Node *ClassType, Node *MemberType)
> +      : Node(KPointerToMemberType, MemberType->hasRHSComponent()),
> +        ClassType(ClassType), MemberType(MemberType) {}
> +
> +  void printLeft(OutputStream &s) const override {
> +    MemberType->printLeft(s);
> +    if (MemberType->hasArray() || MemberType->hasFunction())
> +      s += "(";
> +    else
> +      s += " ";
> +    ClassType->print(s);
> +    s += "::*";
> +  }
> +
> +  void printRight(OutputStream &s) const override {
> +    if (MemberType->hasArray() || MemberType->hasFunction())
> +      s += ")";
> +    MemberType->printRight(s);
> +  }
> +};
> +
> +class NodeOrString {
> +  const void *First;
> +  const void *Second;
> +
> +public:
> +  /* implicit */ NodeOrString(StringView Str) {
> +    const char *FirstChar = Str.begin();
> +    const char *SecondChar = Str.end();
> +    if (SecondChar == nullptr) {
> +      assert(FirstChar == SecondChar);
> +      ++FirstChar, ++SecondChar;
> +    }
> +    First = static_cast<const void *>(FirstChar);
> +    Second = static_cast<const void *>(SecondChar);
> +  }
> +
> +  /* implicit */ NodeOrString(Node *N)
> +      : First(static_cast<const void *>(N)), Second(nullptr) {}
> +  NodeOrString() : First(nullptr), Second(nullptr) {}
> +
> +  bool isString() const { return Second && First; }
> +  bool isNode() const { return First && !Second; }
> +  bool isEmpty() const { return !First && !Second; }
> +
> +  StringView asString() const {
> +    assert(isString());
> +    return StringView(static_cast<const char *>(First),
> +                      static_cast<const char *>(Second));
> +  }
> +
> +  const Node *asNode() const {
> +    assert(isNode());
> +    return static_cast<const Node *>(First);
> +  }
> +};
> +
> +class ArrayType final : public Node {
> +  Node *Base;
> +  NodeOrString Dimension;
> +
> +public:
> +  ArrayType(Node *Base, NodeOrString Dimension)
> +      : Node(KArrayType, true, false, true), Base(Base),
> Dimension(Dimension) {}
> +
> +  // Incomplete array type.
> +  ArrayType(Node *Base) : Node(KArrayType, true, false, true), Base(Base)
> {}
> +
> +  void printLeft(OutputStream &S) const override { Base->printLeft(S); }
> +
> +  void printRight(OutputStream &S) const override {
> +    if (S.back() != ']')
> +      S += " ";
> +    S += "[";
> +    if (Dimension.isString())
> +      S += Dimension.asString();
> +    else if (Dimension.isNode())
> +      Dimension.asNode()->print(S);
> +    S += "]";
> +    Base->printRight(S);
> +  }
> +};
> +
> +class FunctionType final : public Node {
> +  Node *Ret;
> +  NodeArray Params;
> +
> +public:
> +  FunctionType(Node *Ret, NodeArray Params)
> +      : Node(KFunctionType, true, true), Ret(Ret), Params(Params) {}
> +
> +  // Handle C++'s ... quirky decl grammer by using the left & right
> +  // distinction. Consider:
> +  //   int (*f(float))(char) {}
> +  // f is a function that takes a float and returns a pointer to a
> function
> +  // that takes a char and returns an int. If we're trying to print f,
> start
> +  // by printing out the return types's left, then print our parameters,
> then
> +  // finally print right of the return type.
> +  void printLeft(OutputStream &S) const override {
> +    Ret->printLeft(S);
> +    S += " ";
> +  }
> +
> +  void printRight(OutputStream &S) const override {
> +    S += "(";
> +    Params.printWithSeperator(S, ", ");
> +    S += ")";
> +    Ret->printRight(S);
> +  }
> +};
> +
> +class TopLevelFunctionDecl final : public Node {
> +  const Node *Ret;
> +  const Node *Name;
> +  NodeArray Params;
> +
> +public:
> +  TopLevelFunctionDecl(Node *Ret, Node *Name, NodeArray Params)
> +      : Node(KTopLevelFunctionDecl, true, true), Ret(Ret), Name(Name),
> +        Params(Params) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (Ret) {
> +      Ret->printLeft(S);
> +      if (!Ret->hasRHSComponent())
> +        S += " ";
> +    }
> +    Name->print(S);
> +  }
> +
> +  void printRight(OutputStream &S) const override {
> +    S += "(";
> +    Params.printWithSeperator(S, ", ");
> +    S += ")";
> +    if (Ret)
> +      Ret->printRight(S);
> +  }
> +};
> +
> +enum FunctionRefQual : unsigned char {
> +  FrefQualNone,
> +  FrefQualLValue,
> +  FrefQualRValue,
> +};
> +
> +class FunctionRefQualType : public Node {
> +  Node *Fn;
> +  FunctionRefQual Quals;
> +
> +  friend class FunctionQualType;
> +
> +public:
> +  FunctionRefQualType(Node *Fn, FunctionRefQual Quals)
> +      : Node(KFunctionRefQualType, true, true), Fn(Fn), Quals(Quals) {}
> +
> +  void printQuals(OutputStream &S) const {
> +    if (Quals == FrefQualLValue)
> +      S += " &";
> +    else
> +      S += " &&";
> +  }
> +
> +  void printLeft(OutputStream &S) const override { Fn->printLeft(S); }
> +
> +  void printRight(OutputStream &S) const override {
> +    Fn->printRight(S);
> +    printQuals(S);
> +  }
> +};
> +
> +class FunctionQualType final : public QualType {
> +public:
> +  FunctionQualType(Node *Child, Qualifiers Quals)
> +      : QualType(KFunctionQualType, Child, Quals) {}
> +
> +  void printLeft(OutputStream &S) const override { Child->printLeft(S); }
> +
> +  void printRight(OutputStream &S) const override {
> +    if (Child->K == KFunctionRefQualType) {
> +      auto *RefQuals = static_cast<const FunctionRefQualType *>(Child);
> +      RefQuals->Fn->printRight(S);
> +      printQuals(S);
> +      RefQuals->printQuals(S);
> +    } else {
> +      Child->printRight(S);
> +      printQuals(S);
> +    }
> +  }
> +};
> +
> +class LiteralOperator : public Node {
> +  const Node *OpName;
> +
> +public:
> +  LiteralOperator(Node *OpName) : Node(KLiteralOperator), OpName(OpName)
> {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "operator\"\" ";
> +    OpName->print(S);
> +  }
> +};
> +
> +class SpecialName final : public Node {
> +  const StringView Special;
> +  const Node *Child;
> +
> +public:
> +  SpecialName(StringView Special, Node *Child)
> +      : Node(KSpecialName), Special(Special), Child(Child) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += Special;
> +    Child->print(S);
> +  }
> +};
> +
> +class CtorVtableSpecialName final : public Node {
> +  const Node *FirstType;
> +  const Node *SecondType;
> +
> +public:
> +  CtorVtableSpecialName(Node *FirstType, Node *SecondType)
> +      : Node(KCtorVtableSpecialName), FirstType(FirstType),
> +        SecondType(SecondType) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "construction vtable for ";
> +    FirstType->print(S);
> +    S += "-in-";
> +    SecondType->print(S);
> +  }
> +};
> +
> +class QualifiedName final : public Node {
> +  // qualifier::name
> +  const Node *Qualifier;
> +  const Node *Name;
> +
> +  mutable OutputStream::StreamStringView Cache;
> +
> +public:
> +  QualifiedName(Node *Qualifier, Node *Name)
> +      : Node(KQualifiedName), Qualifier(Qualifier), Name(Name) {}
> +
> +  StringView getBaseName() const override { return Name->getBaseName(); }
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (!Cache.empty()) {
> +      S += Cache;
> +      return;
> +    }
> +
> +    OutputStream::StreamPosition Start = S.getCurrentPosition();
> +    if (Qualifier->K != KEmptyName) {
> +      Qualifier->print(S);
> +      S += "::";
> +    }
> +    Name->print(S);
> +    Cache = S.makeStringViewFromPastPosition(Start);
> +  }
> +};
> +
> +class EmptyName : public Node {
> +public:
> +  EmptyName() : Node(KEmptyName) {}
> +  void printLeft(OutputStream &) const override {}
> +};
> +
> +class VectorType final : public Node {
> +  const Node *BaseType;
> +  const NodeOrString Dimension;
> +  const bool IsPixel;
> +
> +public:
> +  VectorType(NodeOrString Dimension)
> +      : Node(KVectorType), BaseType(nullptr), Dimension(Dimension),
> +        IsPixel(true) {}
> +  VectorType(Node *BaseType, NodeOrString Dimension)
> +      : Node(KVectorType), BaseType(BaseType), Dimension(Dimension),
> +        IsPixel(false) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (IsPixel) {
> +      S += "pixel vector[";
> +      S += Dimension.asString();
> +      S += "]";
> +    } else {
> +      BaseType->print(S);
> +      S += " vector[";
> +      if (Dimension.isNode())
> +        Dimension.asNode()->print(S);
> +      else if (Dimension.isString())
> +        S += Dimension.asString();
> +      S += "]";
> +    }
> +  }
> +};
> +
> +class TemplateParams final : public Node {
> +  NodeArray Params;
> +
> +  mutable OutputStream::StreamStringView Cache;
> +
> +public:
> +  TemplateParams(NodeArray Params) : Node(KTemplateParams),
> Params(Params) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (!Cache.empty()) {
> +      S += Cache;
> +      return;
> +    }
> +
> +    OutputStream::StreamPosition Start = S.getCurrentPosition();
> +
> +    S += "<";
> +    Params.printWithSeperator(S, ", ");
> +    if (S.back() == '>')
> +      S += " ";
> +    S += ">";
> +
> +    Cache = S.makeStringViewFromPastPosition(Start);
> +  }
> +};
> +
> +class NameWithTemplateArgs final : public Node {
> +  // name<template_args>
> +  Node *Name;
> +  Node *TemplateArgs;
> +
> +public:
> +  NameWithTemplateArgs(Node *Name, Node *TemplateArgs)
> +      : Node(KNameWithTemplateArgs), Name(Name),
> TemplateArgs(TemplateArgs) {}
> +
> +  StringView getBaseName() const override { return Name->getBaseName(); }
> +
> +  void printLeft(OutputStream &S) const override {
> +    Name->print(S);
> +    TemplateArgs->print(S);
> +  }
> +};
> +
> +class GlobalQualifiedName final : public Node {
> +  Node *Child;
> +
> +public:
> +  GlobalQualifiedName(Node *Child) : Node(KGlobalQualifiedName),
> Child(Child) {}
> +
> +  StringView getBaseName() const override { return Child->getBaseName(); }
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "::";
> +    Child->print(S);
> +  }
> +};
> +
> +class StdQualifiedName final : public Node {
> +  Node *Child;
> +
> +public:
> +  StdQualifiedName(Node *Child) : Node(KStdQualifiedName), Child(Child) {}
> +
> +  StringView getBaseName() const override { return Child->getBaseName(); }
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "std::";
> +    Child->print(S);
> +  }
> +};
> +
> +enum class SpecialSubKind {
> +  allocator,
> +  basic_string,
> +  string,
> +  istream,
> +  ostream,
> +  iostream,
> +};
> +
> +class ExpandedSpecialSubstitution final : public Node {
> +  SpecialSubKind SSK;
> +
> +public:
> +  ExpandedSpecialSubstitution(SpecialSubKind SSK)
> +      : Node(KExpandedSpecialSubstitution), SSK(SSK) {}
> +
> +  StringView getBaseName() const override {
> +    switch (SSK) {
> +    case SpecialSubKind::allocator:
> +      return StringView("allocator");
> +    case SpecialSubKind::basic_string:
> +      return StringView("basic_string");
> +    case SpecialSubKind::string:
> +      return StringView("basic_string");
> +    case SpecialSubKind::istream:
> +      return StringView("basic_istream");
> +    case SpecialSubKind::ostream:
> +      return StringView("basic_ostream");
> +    case SpecialSubKind::iostream:
> +      return StringView("basic_iostream");
> +    }
> +  }
> +
> +  void printLeft(OutputStream &S) const override {
> +    switch (SSK) {
> +    case SpecialSubKind::allocator:
> +      S += "std::basic_string<char, std::char_traits<char>, "
> +           "std::allocator<char> >";
> +      break;
> +    case SpecialSubKind::basic_string:
> +    case SpecialSubKind::string:
> +      S += "std::basic_string<char, std::char_traits<char>, "
> +           "std::allocator<char> >";
> +      break;
> +    case SpecialSubKind::istream:
> +      S += "std::basic_istream<char, std::char_traits<char> >";
> +      break;
> +    case SpecialSubKind::ostream:
> +      S += "std::basic_ostream<char, std::char_traits<char> >";
> +      break;
> +    case SpecialSubKind::iostream:
> +      S += "std::basic_iostream<char, std::char_traits<char> >";
> +      break;
> +    }
> +  }
> +};
> +
> +class SpecialSubstitution final : public Node {
> +public:
> +  SpecialSubKind SSK;
> +
> +  SpecialSubstitution(SpecialSubKind SSK)
> +      : Node(KSpecialSubstitution), SSK(SSK) {}
> +
> +  StringView getBaseName() const override {
> +    switch (SSK) {
> +    case SpecialSubKind::allocator:
> +      return StringView("allocator");
> +    case SpecialSubKind::basic_string:
> +      return StringView("basic_string");
> +    case SpecialSubKind::string:
> +      return StringView("string");
> +    case SpecialSubKind::istream:
> +      return StringView("istream");
> +    case SpecialSubKind::ostream:
> +      return StringView("ostream");
> +    case SpecialSubKind::iostream:
> +      return StringView("iostream");
> +    }
> +  }
> +
> +  void printLeft(OutputStream &S) const override {
> +    switch (SSK) {
> +    case SpecialSubKind::allocator:
> +      S += "std::allocator";
> +      break;
> +    case SpecialSubKind::basic_string:
> +      S += "std::basic_string";
> +      break;
> +    case SpecialSubKind::string:
> +      S += "std::string";
> +      break;
> +    case SpecialSubKind::istream:
> +      S += "std::istream";
> +      break;
> +    case SpecialSubKind::ostream:
> +      S += "std::ostream";
> +      break;
> +    case SpecialSubKind::iostream:
> +      S += "std::iostream";
> +      break;
> +    }
> +  }
> +};
> +
> +class CtorDtorName final : public Node {
> +  const Node *Basename;
> +  const bool IsDtor;
> +
> +public:
> +  CtorDtorName(Node *Basename, bool IsDtor)
> +      : Node(KCtorDtorName), Basename(Basename), IsDtor(IsDtor) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (IsDtor)
> +      S += "~";
> +    S += Basename->getBaseName();
> +  }
> +};
> +
> +class DtorName : public Node {
> +  const Node *Base;
> +
> +public:
> +  DtorName(Node *Base) : Node(KDtorName), Base(Base) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "~";
> +    Base->printLeft(S);
> +  }
> +};
> +
> +class UnnamedTypeName : public Node {
> +  const StringView Count;
> +
> +public:
> +  UnnamedTypeName(StringView Count) : Node(KUnnamedTypeName),
> Count(Count) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "'unnamed";
> +    S += Count;
> +    S += "\'";
> +  }
> +};
> +
> +class LambdaTypeName : public Node {
> +  NodeArray Params;
> +  StringView Count;
> +
> +public:
> +  LambdaTypeName(NodeArray Params, StringView Count)
> +      : Node(KLambdaTypeName), Params(Params), Count(Count) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "\'lambda";
> +    S += Count;
> +    S += "\'(";
> +    Params.printWithSeperator(S, ", ");
> +    S += ")";
> +  }
> +};
> +
> +// -- Expression Nodes --
> +
> +struct Expr : public Node {
> +  Expr() : Node(KExpr) {}
> +};
> +
> +class BinaryExpr : public Expr {
> +  const Node *LHS;
> +  const StringView InfixOperator;
> +  const Node *RHS;
> +
> +public:
> +  BinaryExpr(Node *LHS, StringView InfixOperator, Node *RHS)
> +      : LHS(LHS), InfixOperator(InfixOperator), RHS(RHS) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    // might be a template argument expression, then we need to
> disambiguate
> +    // with parens.
> +    if (InfixOperator == ">")
> +      S += "(";
> +
> +    S += "(";
> +    LHS->print(S);
> +    S += ") ";
> +    S += InfixOperator;
> +    S += " (";
> +    RHS->print(S);
> +    S += ")";
> +
> +    if (InfixOperator == ">")
> +      S += ")";
> +  }
> +};
> +
> +class ArraySubscriptExpr : public Expr {
> +  const Node *Op1;
> +  const Node *Op2;
> +
> +public:
> +  ArraySubscriptExpr(Node *Op1, Node *Op2) : Op1(Op1), Op2(Op2) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "(";
> +    Op1->print(S);
> +    S += ")[";
> +    Op2->print(S);
> +    S += "]";
> +  }
> +};
> +
> +class PostfixExpr : public Expr {
> +  const Node *Child;
> +  const StringView Operand;
> +
> +public:
> +  PostfixExpr(Node *Child, StringView Operand)
> +      : Child(Child), Operand(Operand) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "(";
> +    Child->print(S);
> +    S += ")";
> +    S += Operand;
> +  }
> +};
> +
> +class ConditionalExpr : public Expr {
> +  const Node *Cond;
> +  const Node *Then;
> +  const Node *Else;
> +
> +public:
> +  ConditionalExpr(Node *Cond, Node *Then, Node *Else)
> +      : Cond(Cond), Then(Then), Else(Else) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "(";
> +    Cond->print(S);
> +    S += ") ? (";
> +    Then->print(S);
> +    S += ") : (";
> +    Else->print(S);
> +    S += ")";
> +  }
> +};
> +
> +class MemberExpr : public Expr {
> +  const Node *LHS;
> +  const StringView Kind;
> +  const Node *RHS;
> +
> +public:
> +  MemberExpr(Node *LHS, StringView Kind, Node *RHS)
> +      : LHS(LHS), Kind(Kind), RHS(RHS) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    LHS->print(S);
> +    S += Kind;
> +    RHS->print(S);
> +  }
> +};
> +
> +class EnclosingExpr : public Expr {
> +  const StringView Prefix;
> +  const Node *Infix;
> +  const StringView Postfix;
> +
> +public:
> +  EnclosingExpr(StringView Prefix, Node *Infix, StringView Postfix)
> +      : Prefix(Prefix), Infix(Infix), Postfix(Postfix) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += Prefix;
> +    Infix->print(S);
> +    S += Postfix;
> +  }
> +};
> +
> +class CastExpr : public Expr {
> +  // cast_kind<to>(from)
> +  const StringView CastKind;
> +  const Node *To;
> +  const Node *From;
> +
> +public:
> +  CastExpr(StringView CastKind, Node *To, Node *From)
> +      : CastKind(CastKind), To(To), From(From) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += CastKind;
> +    S += "<";
> +    To->printLeft(S);
> +    S += ">(";
> +    From->printLeft(S);
> +    S += ")";
> +  }
> +};
> +
> +class SizeofParamPackExpr : public Expr {
> +  NodeArray Args;
> +
> +public:
> +  SizeofParamPackExpr(NodeArray Args) : Args(Args) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "sizeof...(";
> +    Args.printWithSeperator(S, ", ");
> +    S += ")";
> +  }
> +};
> +
> +class CallExpr : public Expr {
> +  const Node *Callee;
> +  NodeArray Args;
> +
> +public:
> +  CallExpr(Node *Callee, NodeArray Args) : Callee(Callee), Args(Args) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    Callee->print(S);
> +    S += "(";
> +    Args.printWithSeperator(S, ", ");
> +    S += ")";
> +  }
> +};
> +
> +class NewExpr : public Expr {
> +  // new (expr_list) type(init_list)
> +  NodeArray ExprList;
> +  Node *Type;
> +  NodeArray InitList;
> +  bool IsGlobal; // ::operator new ?
> +  bool IsArray;  // new[] ?
> +public:
> +  NewExpr(NodeArray ExprList, Node *Type, NodeArray InitList, bool
> IsGlobal,
> +          bool IsArray)
> +      : ExprList(ExprList), Type(Type), InitList(InitList),
> IsGlobal(IsGlobal),
> +        IsArray(IsArray) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (IsGlobal)
> +      S += "::operator ";
> +    S += "new";
> +    if (IsArray)
> +      S += "[]";
> +    if (!ExprList.empty()) {
> +      S += "(";
> +      ExprList.printWithSeperator(S, ", ");
> +      S += ")";
> +    }
> +    Type->print(S);
> +    if (!InitList.empty()) {
> +      S += "(";
> +      InitList.printWithSeperator(S, ", ");
> +      S += ")";
> +    }
> +  }
> +};
> +
> +class DeleteExpr : public Expr {
> +  Node *Op;
> +  bool IsGlobal;
> +  bool IsArray;
> +
> +public:
> +  DeleteExpr(Node *Op, bool IsGlobal, bool IsArray)
> +      : Op(Op), IsGlobal(IsGlobal), IsArray(IsArray) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (IsGlobal)
> +      S += "::";
> +    S += "delete";
> +    if (IsArray)
> +      S += "[] ";
> +    Op->print(S);
> +  }
> +};
> +
> +class PrefixExpr : public Expr {
> +  StringView Prefix;
> +  Node *Child;
> +
> +public:
> +  PrefixExpr(StringView Prefix, Node *Child) : Prefix(Prefix),
> Child(Child) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += Prefix;
> +    S += "(";
> +    Child->print(S);
> +    S += ")";
> +  }
> +};
> +
> +class FunctionParam : public Expr {
> +  StringView Number;
> +
> +public:
> +  FunctionParam(StringView Number) : Number(Number) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "fp";
> +    S += Number;
> +  }
> +};
> +
> +class ExprList : public Expr {
> +  NodeArray SubExprs;
> +
> +public:
> +  ExprList(NodeArray SubExprs) : SubExprs(SubExprs) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "(";
> +    SubExprs.printWithSeperator(S, ", ");
> +    S += ")";
> +  }
> +};
> +
> +class ConversionExpr : public Expr {
> +  NodeArray Expressions;
> +  NodeArray Types;
> +
> +public:
> +  ConversionExpr(NodeArray Expressions, NodeArray Types)
> +      : Expressions(Expressions), Types(Types) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "(";
> +    Expressions.printWithSeperator(S, ", ");
> +    S += ")(";
> +    Types.printWithSeperator(S, ", ");
> +    S += ")";
> +  }
> +};
> +
> +class ThrowExpr : public Expr {
> +  const Node *Op;
> +
> +public:
> +  ThrowExpr(Node *Op) : Op(Op) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "throw ";
> +    Op->print(S);
> +  }
> +};
> +
> +class BoolExpr : public Expr {
> +  bool Value;
> +
> +public:
> +  BoolExpr(bool Value) : Value(Value) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += Value ? StringView("true") : StringView("false");
> +  }
> +};
> +
> +class IntegerCastExpr : public Expr {
> +  // ty(integer)
> +  Node *Ty;
> +  StringView Integer;
> +
> +public:
> +  IntegerCastExpr(Node *Ty, StringView Integer) : Ty(Ty),
> Integer(Integer) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    S += "(";
> +    Ty->print(S);
> +    S += ")";
> +    S += Integer;
> +  }
> +};
> +
> +class IntegerExpr : public Expr {
> +  StringView Type;
> +  StringView Value;
> +
> +public:
> +  IntegerExpr(StringView Type, StringView Value) : Type(Type),
> Value(Value) {}
> +
> +  void printLeft(OutputStream &S) const override {
> +    if (Type.size() > 3) {
> +      S += "(";
> +      S += Type;
> +      S += ")";
> +    }
> +
> +    if (Value[0] == 'n') {
> +      S += "-";
> +      S += Value.dropFront(1);
> +    } else
> +      S += Value;
> +
> +    if (Type.size() <= 3)
> +      S += Type;
> +  }
> +};
> +
> +template <class Float> struct FloatData;
> +
> +template <class Float> class FloatExpr : public Expr {
> +  const StringView Contents;
> +
> +public:
> +  FloatExpr(StringView Contents) : Contents(Contents) {}
> +
> +  void printLeft(OutputStream &s) const override {
> +    const char *first = Contents.begin();
> +    const char *last = Contents.end() + 1;
> +
> +    const size_t N = FloatData<Float>::mangled_size;
> +    if (static_cast<std::size_t>(last - first) > N) {
> +      last = first + N;
> +      union {
> +        Float value;
> +        char buf[sizeof(Float)];
> +      };
> +      const char *t = first;
> +      char *e = buf;
> +      for (; t != last; ++t, ++e) {
> +        unsigned d1 = isdigit(*t) ? static_cast<unsigned>(*t - '0')
> +                                  : static_cast<unsigned>(*t - 'a' + 10);
> +        ++t;
> +        unsigned d0 = isdigit(*t) ? static_cast<unsigned>(*t - '0')
> +                                  : static_cast<unsigned>(*t - 'a' + 10);
> +        *e = static_cast<char>((d1 << 4) + d0);
> +      }
> +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> +      std::reverse(buf, e);
> +#endif
> +      char num[FloatData<Float>::max_demangled_size] = {0};
> +      int n = snprintf(num, sizeof(num), FloatData<Float>::spec, value);
> +      s += StringView(num, num + n);
> +    }
> +  }
> +};
> +
>  template <std::size_t N>
>  class arena
>  {
> @@ -148,168 +1511,118 @@ operator!=(const short_alloc<T, N>& x, c
>      return !(x == y);
>  }
>
> -template <class T>
> -class malloc_alloc
> -{
> -public:
> -    typedef T value_type;
> -    typedef T& reference;
> -    typedef const T& const_reference;
> -    typedef T* pointer;
> -    typedef const T* const_pointer;
> -    typedef std::size_t size_type;
> -    typedef std::ptrdiff_t difference_type;
> -
> -    malloc_alloc() = default;
> -    template <class U> malloc_alloc(const malloc_alloc<U>&) noexcept {}
> -
> -    T* allocate(std::size_t n)
> -    {
> -        return static_cast<T*>(std::malloc(n*sizeof(T)));
> -    }
> -    void deallocate(T* p, std::size_t) noexcept
> -    {
> -        std::free(p);
> -    }
> -
> -    template <class U> struct rebind { using other = malloc_alloc<U>; };
> -    template <class U, class... Args>
> -    void construct(U* p, Args&&... args)
> -    {
> -        ::new ((void*)p) U(std::forward<Args>(args)...);
> -    }
> -    void destroy(T* p)
> -    {
> -        p->~T();
> -    }
> -};
> -
> -template <class T, class U>
> -inline
> -bool
> -operator==(const malloc_alloc<T>&, const malloc_alloc<U>&) noexcept
> -{
> -    return true;
> -}
> -
> -template <class T, class U>
> -inline
> -bool
> -operator!=(const malloc_alloc<T>& x, const malloc_alloc<U>& y) noexcept
> -{
> -    return !(x == y);
> -}
> -
>  const size_t bs = 4 * 1024;
>  template <class T> using Alloc = short_alloc<T, bs>;
>  template <class T> using Vector = std::vector<T, Alloc<T>>;
>
> -template <class StrT>
> -struct string_pair
> -{
> -    StrT first;
> -    StrT second;
> +class BumpPointerAllocator {
> +  struct BlockMeta {
> +    BlockMeta* Next;
> +    size_t Current;
> +  };
> +
> +  static constexpr size_t AllocSize = 4096;
> +  static constexpr size_t UsableAllocSize = AllocSize - sizeof(BlockMeta);
> +
> +  alignas(16) char InitialBuffer[AllocSize];
> +  BlockMeta* BlockList = nullptr;
> +
> +  void grow() {
> +    char* NewMeta = new char[AllocSize];
> +    BlockList = new (NewMeta) BlockMeta{BlockList, 0};
> +  }
> +
> +  void* allocateMassive(size_t NBytes) {
> +    NBytes += sizeof(BlockMeta);
> +    BlockMeta* NewMeta = reinterpret_cast<BlockMeta*>(new char[NBytes]);
> +    BlockList->Next = new (NewMeta) BlockMeta{BlockList->Next, 0};
> +    return static_cast<void*>(NewMeta + 1);
> +  }
>
> -    string_pair() = default;
> -    string_pair(StrT f) : first(std::move(f)) {}
> -    string_pair(StrT f, StrT s)
> -        : first(std::move(f)), second(std::move(s)) {}
> -    template <size_t N>
> -        string_pair(const char (&s)[N]) : first(s, N-1) {}
> +public:
> +  BumpPointerAllocator()
> +      : BlockList(new (InitialBuffer) BlockMeta{nullptr, 0}) {}
>
> -    size_t size() const {return first.size() + second.size();}
> -    bool empty() const { return first.empty() && second.empty(); }
> -    StrT full() const {return first + second;}
> -    StrT move_full() {return std::move(first) + std::move(second);}
> +  void* allocate(size_t N) {
> +    N = (N + 15u) & ~15u;
> +    if (N + BlockList->Current >= UsableAllocSize) {
> +      if (N > UsableAllocSize)
> +        return allocateMassive(N);
> +      grow();
> +    }
> +    BlockList->Current += N;
> +    return static_cast<void*>(reinterpret_cast<char*>(BlockList + 1) +
> +                              BlockList->Current - N);
> +  }
> +
> +  ~BumpPointerAllocator() {
> +    while (BlockList) {
> +      BlockMeta* Tmp = BlockList;
> +      BlockList = BlockList->Next;
> +      if (reinterpret_cast<char*>(Tmp) != InitialBuffer)
> +        delete[] reinterpret_cast<char*>(Tmp);
> +    }
> +  }
>  };
>
>  struct Db
>  {
> -    typedef std::basic_string<char, std::char_traits<char>,
> -                              malloc_alloc<char>> String;
> -    typedef Vector<string_pair<String>> sub_type;
> +    typedef Vector<Node*> sub_type;
>      typedef Vector<sub_type> template_param_type;
>      sub_type names;
>      template_param_type subs;
>      Vector<template_param_type> template_param;
> -    unsigned cv = 0;
> -    unsigned ref = 0;
> +    Qualifiers cv = QualNone;
> +    FunctionRefQual ref = FrefQualNone;
>      unsigned encoding_depth = 0;
>      bool parsed_ctor_dtor_cv = false;
>      bool tag_templates = true;
>      bool fix_forward_references = false;
>      bool try_to_parse_template_args = true;
>
> +    BumpPointerAllocator ASTAllocator;
> +
>      template <size_t N>
>      Db(arena<N>& ar) :
>          names(ar),
>          subs(0, names, ar),
>          template_param(0, subs, ar)
>      {}
> -};
> -
>
> -const char* parse_type(const char* first, const char* last, Db& db);
> -const char* parse_encoding(const char* first, const char* last, Db& db);
> -const char* parse_name(const char* first, const char* last, Db& db,
> -                       bool* ends_with_template_args = 0);
> -const char* parse_expression(const char* first, const char* last, Db& db);
> -const char* parse_template_args(const char* first, const char* last, Db&
> db);
> -const char* parse_operator_name(const char* first, const char* last, Db&
> db);
> -const char* parse_unqualified_name(const char* first, const char* last,
> Db& db);
> -const char* parse_decltype(const char* first, const char* last, Db& db);
> +    template <class T, class... Args> T* make(Args&& ...args)
> +    {
> +        return new (ASTAllocator.allocate(sizeof(T)))
> +            T(std::forward<Args>(args)...);
> +    }
>
> -template <class C>
> -void
> -print_stack(const C& db)
> -{
> -    fprintf(stderr, "---------\n");
> -    fprintf(stderr, "names:\n");
> -    for (auto& s : db.names)
> -        fprintf(stderr, "{%s#%s}\n", s.first.c_str(), s.second.c_str());
> -    int i = -1;
> -    fprintf(stderr, "subs:\n");
> -    for (auto& v : db.subs)
> +    template <class It> NodeArray makeNodeArray(It begin, It end)
>      {
> -        if (i >= 0)
> -            fprintf(stderr, "S%i_ = {", i);
> -        else
> -            fprintf(stderr, "S_  = {");
> -        for (auto& s : v)
> -            fprintf(stderr, "{%s#%s}", s.first.c_str(), s.second.c_str());
> -        fprintf(stderr, "}\n");
> -        ++i;
> -    }
> -    fprintf(stderr, "template_param:\n");
> -    for (auto& t : db.template_param)
> -    {
> -        fprintf(stderr, "--\n");
> -        i = -1;
> -        for (auto& v : t)
> -        {
> -            if (i >= 0)
> -                fprintf(stderr, "T%i_ = {", i);
> -            else
> -                fprintf(stderr, "T_  = {");
> -            for (auto& s : v)
> -                fprintf(stderr, "{%s#%s}", s.first.c_str(),
> s.second.c_str());
> -            fprintf(stderr, "}\n");
> -            ++i;
> -        }
> +        size_t sz = static_cast<size_t>(end - begin);
> +        void* mem = ASTAllocator.allocate(sizeof(Node*) * sz);
> +        Node** data = new (mem) Node*[sz];
> +        std::copy(begin, end, data);
> +        return NodeArray(data, sz);
>      }
> -    fprintf(stderr, "---------\n\n");
> -}
>
> -template <class C>
> -void
> -print_state(const char* msg, const char* first, const char* last, const
> C& db)
> -{
> -    fprintf(stderr, "%s: ", msg);
> -    for (; first != last; ++first)
> -        fprintf(stderr, "%c", *first);
> -    fprintf(stderr, "\n");
> -    print_stack(db);
> -}
> +    NodeArray popTrailingNodeArray(size_t FromPosition)
> +    {
> +        assert(FromPosition <= names.size());
> +        NodeArray res = makeNodeArray(
> +            names.begin() + (long)FromPosition, names.end());
> +        names.erase(names.begin() + (long)FromPosition, names.end());
> +        return res;
> +    }
> +};
> +
> +const char* parse_type(const char* first, const char* last, Db& db);
> +const char* parse_encoding(const char* first, const char* last, Db& db);
> +const char* parse_name(const char* first, const char* last, Db& db,
> +                       bool* ends_with_template_args = 0);
> +const char* parse_expression(const char* first, const char* last, Db& db);
> +const char* parse_template_args(const char* first, const char* last, Db&
> db);
> +const char* parse_operator_name(const char* first, const char* last, Db&
> db);
> +const char* parse_unqualified_name(const char* first, const char* last,
> Db& db);
> +const char* parse_decltype(const char* first, const char* last, Db& db);
>
>  // <number> ::= [n] <non-negative decimal integer>
>
> @@ -339,30 +1652,30 @@ parse_number(const char* first, const ch
>  }
>
>  template <class Float>
> -struct float_data;
> +struct FloatData;
>
>  template <>
> -struct float_data<float>
> +struct FloatData<float>
>  {
>      static const size_t mangled_size = 8;
>      static const size_t max_demangled_size = 24;
>      static constexpr const char* spec = "%af";
>  };
>
> -constexpr const char* float_data<float>::spec;
> +constexpr const char* FloatData<float>::spec;
>
>  template <>
> -struct float_data<double>
> +struct FloatData<double>
>  {
>      static const size_t mangled_size = 16;
>      static const size_t max_demangled_size = 32;
>      static constexpr const char* spec = "%a";
>  };
>
> -constexpr const char* float_data<double>::spec;
> +constexpr const char* FloatData<double>::spec;
>
>  template <>
> -struct float_data<long double>
> +struct FloatData<long double>
>  {
>  #if defined(__mips__) && defined(__mips_n64) || defined(__aarch64__) || \
>      defined(__wasm__)
> @@ -376,46 +1689,27 @@ struct float_data<long double>
>      static constexpr const char* spec = "%LaL";
>  };
>
> -constexpr const char* float_data<long double>::spec;
> +constexpr const char* FloatData<long double>::spec;
>
>  template <class Float>
>  const char*
>  parse_floating_number(const char* first, const char* last, Db& db)
>  {
> -    const size_t N = float_data<Float>::mangled_size;
> -    if (static_cast<std::size_t>(last - first) > N)
> +    const size_t N = FloatData<Float>::mangled_size;
> +    if (static_cast<std::size_t>(last - first) <= N)
> +        return first;
> +    last = first + N;
> +    const char* t = first;
> +    for (; t != last; ++t)
>      {
> -        last = first + N;
> -        union
> -        {
> -            Float value;
> -            char buf[sizeof(Float)];
> -        };
> -        const char* t = first;
> -        char* e = buf;
> -        for (; t != last; ++t, ++e)
> -        {
> -            if (!isxdigit(*t))
> -                return first;
> -            unsigned d1 = isdigit(*t) ? static_cast<unsigned>(*t - '0') :
> -                                        static_cast<unsigned>(*t - 'a' +
> 10);
> -            ++t;
> -            unsigned d0 = isdigit(*t) ? static_cast<unsigned>(*t - '0') :
> -                                        static_cast<unsigned>(*t - 'a' +
> 10);
> -            *e = static_cast<char>((d1 << 4) + d0);
> -        }
> -        if (*t == 'E')
> -        {
> -#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> -            std::reverse(buf, e);
> -#endif
> -            char num[float_data<Float>::max_demangled_size] = {0};
> -            int n = snprintf(num, sizeof(num), float_data<Float>::spec,
> value);
> -            if (static_cast<std::size_t>(n) >= sizeof(num))
> -                return first;
> -            db.names.push_back(Db::String(num,
> static_cast<std::size_t>(n)));
> -            first = t+1;
> -        }
> +        if (!isxdigit(*t))
> +            return first;
> +    }
> +    if (*t == 'E')
> +    {
> +        db.names.push_back(
> +            db.make<FloatExpr<Float>>(StringView(first, t)));
> +        first = t + 1;
>      }
>      return first;
>  }
> @@ -440,11 +1734,11 @@ parse_source_name(const char* first, con
>              }
>              if (static_cast<size_t>(last - t) >= n)
>              {
> -                Db::String r(t, n);
> +                StringView r(t, t + n);
>                  if (r.substr(0, 10) == "_GLOBAL__N")
> -                    db.names.push_back("(anonymous namespace)");
> +                    db.names.push_back(db.make<NameType>("(anonymous
> namespace)"));
>                  else
> -                    db.names.push_back(std::move(r));
> +                    db.names.push_back(db.make<NameType>(r));
>                  first = t + n;
>              }
>          }
> @@ -473,27 +1767,32 @@ parse_substitution(const char* first, co
>              switch (first[1])
>              {
>              case 'a':
> -                db.names.push_back("std::allocator");
> +                db.names.push_back(
> +                    db.make<SpecialSubstitution>(
> +                        SpecialSubKind::allocator));
>                  first += 2;
>                  break;
>              case 'b':
> -                db.names.push_back("std::basic_string");
> +                db.names.push_back(
> +                    db.make<SpecialSubstitution>(
> SpecialSubKind::basic_string));
>                  first += 2;
>                  break;
>              case 's':
> -                db.names.push_back("std::string");
> +                db.names.push_back(
> +                    db.make<SpecialSubstitution>(
> +                        SpecialSubKind::string));
>                  first += 2;
>                  break;
>              case 'i':
> -                db.names.push_back("std::istream");
> +                db.names.push_back(db.make<SpecialSubstitution>(
> SpecialSubKind::istream));
>                  first += 2;
>                  break;
>              case 'o':
> -                db.names.push_back("std::ostream");
> +                db.names.push_back(db.make<SpecialSubstitution>(
> SpecialSubKind::ostream));
>                  first += 2;
>                  break;
>              case 'd':
> -                db.names.push_back("std::iostream");
> +                db.names.push_back(db.make<SpecialSubstitution>(
> SpecialSubKind::iostream));
>                  first += 2;
>                  break;
>              case '_':
> @@ -578,87 +1877,87 @@ parse_builtin_type(const char* first, co
>          switch (*first)
>          {
>          case 'v':
> -            db.names.push_back("void");
> +            db.names.push_back(db.make<NameType>("void"));
>              ++first;
>              break;
>          case 'w':
> -            db.names.push_back("wchar_t");
> +            db.names.push_back(db.make<NameType>("wchar_t"));
>              ++first;
>              break;
>          case 'b':
> -            db.names.push_back("bool");
> +            db.names.push_back(db.make<NameType>("bool"));
>              ++first;
>              break;
>          case 'c':
> -            db.names.push_back("char");
> +            db.names.push_back(db.make<NameType>("char"));
>              ++first;
>              break;
>          case 'a':
> -            db.names.push_back("signed char");
> +            db.names.push_back(db.make<NameType>("signed char"));
>              ++first;
>              break;
>          case 'h':
> -            db.names.push_back("unsigned char");
> +            db.names.push_back(db.make<NameType>("unsigned char"));
>              ++first;
>              break;
>          case 's':
> -            db.names.push_back("short");
> +            db.names.push_back(db.make<NameType>("short"));
>              ++first;
>              break;
>          case 't':
> -            db.names.push_back("unsigned short");
> +            db.names.push_back(db.make<NameType>("unsigned short"));
>              ++first;
>              break;
>          case 'i':
> -            db.names.push_back("int");
> +            db.names.push_back(db.make<NameType>("int"));
>              ++first;
>              break;
>          case 'j':
> -            db.names.push_back("unsigned int");
> +            db.names.push_back(db.make<NameType>("unsigned int"));
>              ++first;
>              break;
>          case 'l':
> -            db.names.push_back("long");
> +            db.names.push_back(db.make<NameType>("long"));
>              ++first;
>              break;
>          case 'm':
> -            db.names.push_back("unsigned long");
> +            db.names.push_back(db.make<NameType>("unsigned long"));
>              ++first;
>              break;
>          case 'x':
> -            db.names.push_back("long long");
> +            db.names.push_back(db.make<NameType>("long long"));
>              ++first;
>              break;
>          case 'y':
> -            db.names.push_back("unsigned long long");
> +            db.names.push_back(db.make<NameType>("unsigned long long"));
>              ++first;
>              break;
>          case 'n':
> -            db.names.push_back("__int128");
> +            db.names.push_back(db.make<NameType>("__int128"));
>              ++first;
>              break;
>          case 'o':
> -            db.names.push_back("unsigned __int128");
> +            db.names.push_back(db.make<NameType>("unsigned __int128"));
>              ++first;
>              break;
>          case 'f':
> -            db.names.push_back("float");
> +            db.names.push_back(db.make<NameType>("float"));
>              ++first;
>              break;
>          case 'd':
> -            db.names.push_back("double");
> +            db.names.push_back(db.make<NameType>("double"));
>              ++first;
>              break;
>          case 'e':
> -            db.names.push_back("long double");
> +            db.names.push_back(db.make<NameType>("long double"));
>              ++first;
>              break;
>          case 'g':
> -            db.names.push_back("__float128");
> +            db.names.push_back(db.make<NameType>("__float128"));
>              ++first;
>              break;
>          case 'z':
> -            db.names.push_back("...");
> +            db.names.push_back(db.make<NameType>("..."));
>              ++first;
>              break;
>          case 'u':
> @@ -674,39 +1973,39 @@ parse_builtin_type(const char* first, co
>                  switch (first[1])
>                  {
>                  case 'd':
> -                    db.names.push_back("decimal64");
> +                    db.names.push_back(db.make<NameType>("decimal64"));
>                      first += 2;
>                      break;
>                  case 'e':
> -                    db.names.push_back("decimal128");
> +                    db.names.push_back(db.make<NameType>("decimal128"));
>                      first += 2;
>                      break;
>                  case 'f':
> -                    db.names.push_back("decimal32");
> +                    db.names.push_back(db.make<NameType>("decimal32"));
>                      first += 2;
>                      break;
>                  case 'h':
> -                    db.names.push_back("decimal16");
> +                    db.names.push_back(db.make<NameType>("decimal16"));
>                      first += 2;
>                      break;
>                  case 'i':
> -                    db.names.push_back("char32_t");
> +                    db.names.push_back(db.make<NameType>("char32_t"));
>                      first += 2;
>                      break;
>                  case 's':
> -                    db.names.push_back("char16_t");
> +                    db.names.push_back(db.make<NameType>("char16_t"));
>                      first += 2;
>                      break;
>                  case 'a':
> -                    db.names.push_back("auto");
> +                    db.names.push_back(db.make<NameType>("auto"));
>                      first += 2;
>                      break;
>                  case 'c':
> -                    db.names.push_back("decltype(auto)");
> +                    db.names.push_back(db.make<
> NameType>("decltype(auto)"));
>                      first += 2;
>                      break;
>                  case 'n':
> -                    db.names.push_back("std::nullptr_t");
> +                    db.names.push_back(db.make<
> NameType>("std::nullptr_t"));
>                      first += 2;
>                      break;
>                  }
> @@ -717,27 +2016,27 @@ parse_builtin_type(const char* first, co
>      return first;
>  }
>
> -// <CV-qualifiers> ::= [r] [V] [K]
> +// <CV-Qualifiers> ::= [r] [V] [K]
>
>  const char*
> -parse_cv_qualifiers(const char* first, const char* last, unsigned& cv)
> +parse_cv_qualifiers(const char* first, const char* last, Qualifiers& cv)
>  {
> -    cv = 0;
> +    cv = QualNone;
>      if (first != last)
>      {
>          if (*first == 'r')
>          {
> -            cv |= 4;
> +            addQualifiers(cv, QualRestrict);
>              ++first;
>          }
>          if (*first == 'V')
>          {
> -            cv |= 2;
> +            addQualifiers(cv, QualVolatile);
>              ++first;
>          }
>          if (*first == 'K')
>          {
> -            cv |= 1;
> +            addQualifiers(cv, QualConst);
>              ++first;
>          }
>      }
> @@ -766,7 +2065,7 @@ parse_template_param(const char* first,
>                  }
>                  else
>                  {
> -                    db.names.push_back("T_");
> +                    db.names.push_back(db.make<NameType>("T_"));
>                      first += 2;
>                      db.fix_forward_references = true;
>                  }
> @@ -791,7 +2090,8 @@ parse_template_param(const char* first,
>                  }
>                  else
>                  {
> -                    db.names.push_back(Db::String(first, t+1));
> +                    db.names.push_back(
> +                        db.make<NameType>(StringView(first, t + 1)));
>                      first = t+1;
>                      db.fix_forward_references = true;
>                  }
> @@ -816,11 +2116,12 @@ parse_const_cast_expr(const char* first,
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto expr = db.names.back().move_full();
> +                auto from_expr = db.names.back();
>                  db.names.pop_back();
>                  if (db.names.empty())
>                      return first;
> -                db.names.back() = "const_cast<" +
> db.names.back().move_full() + ">(" + expr + ")";
> +                db.names.back() = db.make<CastExpr>(
> +                    "const_cast", db.names.back(), from_expr);
>                  first = t1;
>              }
>          }
> @@ -843,11 +2144,12 @@ parse_dynamic_cast_expr(const char* firs
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto expr = db.names.back().move_full();
> +                auto from_expr = db.names.back();
>                  db.names.pop_back();
>                  if (db.names.empty())
>                      return first;
> -                db.names.back() = "dynamic_cast<" +
> db.names.back().move_full() + ">(" + expr + ")";
> +                db.names.back() = db.make<CastExpr>(
> +                    "dynamic_cast", db.names.back(), from_expr);
>                  first = t1;
>              }
>          }
> @@ -870,11 +2172,12 @@ parse_reinterpret_cast_expr(const char*
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto expr = db.names.back().move_full();
> +                auto from_expr = db.names.back();
>                  db.names.pop_back();
>                  if (db.names.empty())
>                      return first;
> -                db.names.back() = "reinterpret_cast<" +
> db.names.back().move_full() + ">(" + expr + ")";
> +                db.names.back() = db.make<CastExpr>(
> +                    "reinterpret_cast", db.names.back(), from_expr);
>                  first = t1;
>              }
>          }
> @@ -897,9 +2200,10 @@ parse_static_cast_expr(const char* first
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto expr = db.names.back().move_full();
> +                auto from_expr = db.names.back();
>                  db.names.pop_back();
> -                db.names.back() = "static_cast<" +
> db.names.back().move_full() + ">(" + expr + ")";
> +                db.names.back() = db.make<CastExpr>(
> +                    "static_cast", db.names.back(), from_expr);
>                  first = t1;
>              }
>          }
> @@ -933,7 +2237,8 @@ parse_sizeof_type_expr(const char* first
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back() = "sizeof (" + db.names.back().move_full() +
> ")";
> +            db.names.back() = db.make<EnclosingExpr>(
> +                "sizeof (", db.names.back(), ")");
>              first = t;
>          }
>      }
> @@ -952,7 +2257,8 @@ parse_sizeof_expr_expr(const char* first
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back() = "sizeof (" + db.names.back().move_full() +
> ")";
> +            db.names.back() = db.make<EnclosingExpr>(
> +                "sizeof (", db.names.back(), ")");
>              first = t;
>          }
>      }
> @@ -969,30 +2275,21 @@ parse_sizeof_param_pack_expr(const char*
>          size_t k0 = db.names.size();
>          const char* t = parse_template_param(first+2, last, db);
>          size_t k1 = db.names.size();
> -        if (t != first+2)
> +        if (t != first+2 && k0 <= k1)
>          {
> -            Db::String tmp("sizeof...(");
> -            size_t k = k0;
> -            if (k != k1)
> -            {
> -                tmp += db.names[k].move_full();
> -                for (++k; k != k1; ++k)
> -                    tmp += ", " + db.names[k].move_full();
> -            }
> -            tmp += ")";
> -            for (; k1 != k0; --k1)
> -                db.names.pop_back();
> -            db.names.push_back(std::move(tmp));
> +            Node* sizeof_expr = db.make<SizeofParamPackExpr>(
> +                db.popTrailingNodeArray(k0));
> +            db.names.push_back(sizeof_expr);
>              first = t;
>          }
>      }
>      return first;
>  }
>
> -// <function-param> ::= fp <top-level CV-qualifiers> _
>                  # L == 0, first parameter
> -//                  ::= fp <top-level CV-qualifiers> <parameter-2
> non-negative number> _   # L == 0, second and later parameters
> -//                  ::= fL <L-1 non-negative number> p <top-level
> CV-qualifiers> _         # L > 0, first parameter
> -//                  ::= fL <L-1 non-negative number> p <top-level
> CV-qualifiers> <parameter-2 non-negative number> _   # L > 0, second and
> later parameters
> +// <function-param> ::= fp <top-level CV-Qualifiers> _
>                  # L == 0, first parameter
> +//                  ::= fp <top-level CV-Qualifiers> <parameter-2
> non-negative number> _   # L == 0, second and later parameters
> +//                  ::= fL <L-1 non-negative number> p <top-level
> CV-Qualifiers> _         # L > 0, first parameter
> +//                  ::= fL <L-1 non-negative number> p <top-level
> CV-Qualifiers> <parameter-2 non-negative number> _   # L > 0, second and
> later parameters
>
>  const char*
>  parse_function_param(const char* first, const char* last, Db& db)
> @@ -1001,18 +2298,19 @@ parse_function_param(const char* first,
>      {
>          if (first[1] == 'p')
>          {
> -            unsigned cv;
> +            Qualifiers cv;
>              const char* t = parse_cv_qualifiers(first+2, last, cv);
>              const char* t1 = parse_number(t, last);
>              if (t1 != last && *t1 == '_')
>              {
> -                db.names.push_back("fp" + Db::String(t, t1));
> +                db.names.push_back(
> +                    db.make<FunctionParam>(StringView(t, t1)));
>                  first = t1+1;
>              }
>          }
>          else if (first[1] == 'L')
>          {
> -            unsigned cv;
> +            Qualifiers cv;
>              const char* t0 = parse_number(first+2, last);
>              if (t0 != last && *t0 == 'p')
>              {
> @@ -1021,7 +2319,8 @@ parse_function_param(const char* first,
>                  const char* t1 = parse_number(t, last);
>                  if (t1 != last && *t1 == '_')
>                  {
> -                    db.names.push_back("fp" + Db::String(t, t1));
> +                    db.names.push_back(
> +                        db.make<FunctionParam>(StringView(t, t1)));
>                      first = t1+1;
>                  }
>              }
> @@ -1042,7 +2341,8 @@ parse_sizeof_function_param_pack_expr(co
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back() = "sizeof...(" + db.names.back().move_full()
> + ")";
> +            db.names.back() = db.make<EnclosingExpr>(
> +                "sizeof...(", db.names.back(), ")");
>              first = t;
>          }
>      }
> @@ -1066,7 +2366,8 @@ parse_typeid_expr(const char* first, con
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back() = "typeid(" + db.names.back().move_full() +
> ")";
> +            db.names.back() = db.make<EnclosingExpr>(
> +                "typeid(", db.names.back(), ")");
>              first = t;
>          }
>      }
> @@ -1085,7 +2386,7 @@ parse_throw_expr(const char* first, cons
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back() = "throw " + db.names.back().move_full();
> +            db.names.back() = db.make<ThrowExpr>(db.names.back());
>              first = t;
>          }
>      }
> @@ -1107,9 +2408,10 @@ parse_dot_star_expr(const char* first, c
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto expr = db.names.back().move_full();
> +                auto rhs_expr = db.names.back();
>                  db.names.pop_back();
> -                db.names.back().first += ".*" + expr;
> +                db.names.back() = db.make<MemberExpr>(
> +                    db.names.back(), ".*", rhs_expr);
>                  first = t1;
>              }
>          }
> @@ -1132,9 +2434,10 @@ parse_simple_id(const char* first, const
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto args = db.names.back().move_full();
> +                auto args = db.names.back();
>                  db.names.pop_back();
> -                db.names.back().first += std::move(args);
> +                db.names.back() =
> +                    db.make<NameWithTemplateArgs>(db.names.back(), args);
>              }
>              first = t1;
>          }
> @@ -1196,7 +2499,8 @@ parse_unresolved_type(const char* first,
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first.insert(0, "std::");
> +                        db.names.back() =
> +                            db.make<StdQualifiedName>(db.names.back());
>                          db.subs.push_back(Db::sub_type(1,
> db.names.back(), db.names.get_allocator()));
>                          first = t;
>                      }
> @@ -1223,7 +2527,7 @@ parse_destructor_name(const char* first,
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back().first.insert(0, "~");
> +            db.names.back() = db.make<DtorName>(db.names.back());
>              first = t;
>          }
>      }
> @@ -1255,9 +2559,11 @@ parse_base_unresolved_name(const char* f
>                      {
>                          if (db.names.size() < 2)
>                              return first;
> -                        auto args = db.names.back().move_full();
> +                        auto args = db.names.back();
>                          db.names.pop_back();
> -                        db.names.back().first += std::move(args);
> +                        db.names.back() =
> +                            db.make<NameWithTemplateArgs>(
> +                                db.names.back(), args);
>                      }
>                  }
>              }
> @@ -1281,9 +2587,11 @@ parse_base_unresolved_name(const char* f
>                      {
>                          if (db.names.size() < 2)
>                              return first;
> -                        auto args = db.names.back().move_full();
> +                        auto args = db.names.back();
>                          db.names.pop_back();
> -                        db.names.back().first += std::move(args);
> +                        db.names.back() =
> +                            db.make<NameWithTemplateArgs>(
> +                                db.names.back(), args);
>                      }
>                  }
>              }
> @@ -1331,7 +2639,8 @@ parse_unresolved_name(const char* first,
>              {
>                  if (db.names.empty())
>                      return first;
> -                db.names.back().first.insert(0, "::");
> +                db.names.back() =
> +                    db.make<GlobalQualifiedName>(db.names.back());
>              }
>              first = t2;
>          }
> @@ -1349,9 +2658,10 @@ parse_unresolved_name(const char* first,
>                  {
>                      if (db.names.size() < 2)
>                          return first;
> -                    auto args = db.names.back().move_full();
> +                    auto args = db.names.back();
>                      db.names.pop_back();
> -                    db.names.back().first += std::move(args);
> +                    db.names.back() = db.make<NameWithTemplateArgs>(
> +                        db.names.back(), args);
>                      t = t1;
>                      if (t == last)
>                      {
> @@ -1364,9 +2674,10 @@ parse_unresolved_name(const char* first,
>                      t1 = parse_unresolved_qualifier_level(t, last, db);
>                      if (t1 == t || t1 == last || db.names.size() < 2)
>                          return first;
> -                    auto s = db.names.back().move_full();
> +                    auto s = db.names.back();
>                      db.names.pop_back();
> -                    db.names.back().first += "::" + std::move(s);
> +                    db.names.back() =
> +                        db.make<QualifiedName>(db.names.back(), s);
>                      t = t1;
>                  }
>                  ++t;
> @@ -1379,9 +2690,10 @@ parse_unresolved_name(const char* first,
>                  }
>                  if (db.names.size() < 2)
>                      return first;
> -                auto s = db.names.back().move_full();
> +                auto s = db.names.back();
>                  db.names.pop_back();
> -                db.names.back().first += "::" + std::move(s);
> +                db.names.back() =
> +                    db.make<QualifiedName>(db.names.back(), s);
>                  first = t1;
>              }
>              else
> @@ -1396,9 +2708,11 @@ parse_unresolved_name(const char* first,
>                      {
>                          if (db.names.size() < 2)
>                              return first;
> -                        auto args = db.names.back().move_full();
> +                        auto args = db.names.back();
>                          db.names.pop_back();
> -                        db.names.back().first += std::move(args);
> +                        db.names.back() =
> +                            db.make<NameWithTemplateArgs>(
> +                                db.names.back(), args);
>                          t = t1;
>                      }
>                      t1 = parse_base_unresolved_name(t, last, db);
> @@ -1410,9 +2724,10 @@ parse_unresolved_name(const char* first,
>                      }
>                      if (db.names.size() < 2)
>                          return first;
> -                    auto s = db.names.back().move_full();
> +                    auto s = db.names.back();
>                      db.names.pop_back();
> -                    db.names.back().first += "::" + std::move(s);
> +                    db.names.back() =
> +                        db.make<QualifiedName>(db.names.back(), s);
>                      first = t1;
>                  }
>                  else
> @@ -1425,16 +2740,19 @@ parse_unresolved_name(const char* first,
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first.insert(0, "::");
> +                        db.names.back() =
> +                            db.make<GlobalQualifiedName>(
> +                                db.names.back());
>                      }
>                      while (*t != 'E')
>                      {
>                          t1 = parse_unresolved_qualifier_level(t, last,
> db);
>                          if (t1 == t || t1 == last || db.names.size() < 2)
>                              return first;
> -                        auto s = db.names.back().move_full();
> +                        auto s = db.names.back();
>                          db.names.pop_back();
> -                        db.names.back().first += "::" + std::move(s);
> +                        db.names.back() = db.make<QualifiedName>(
> +                            db.names.back(), s);
>                          t = t1;
>                      }
>                      ++t;
> @@ -1447,9 +2765,10 @@ parse_unresolved_name(const char* first,
>                      }
>                      if (db.names.size() < 2)
>                          return first;
> -                    auto s = db.names.back().move_full();
> +                    auto s = db.names.back();
>                      db.names.pop_back();
> -                    db.names.back().first += "::" + std::move(s);
> +                    db.names.back() =
> +                        db.make<QualifiedName>(db.names.back(), s);
>                      first = t1;
>                  }
>              }
> @@ -1473,11 +2792,11 @@ parse_dot_expr(const char* first, const
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto name = db.names.back().move_full();
> +                auto name = db.names.back();
>                  db.names.pop_back();
>                  if (db.names.empty())
>                      return first;
> -                db.names.back().first += "." + name;
> +                db.names.back() = db.make<MemberExpr>(db.names.back(),
> ".", name);
>                  first = t1;
>              }
>          }
> @@ -1493,44 +2812,25 @@ parse_call_expr(const char* first, const
>      if (last - first >= 4 && first[0] == 'c' && first[1] == 'l')
>      {
>          const char* t = parse_expression(first+2, last, db);
> -        if (t != first+2)
> +        if (t == last || t == first + 2 || db.names.empty())
> +            return first;
> +        Node* callee = db.names.back();
> +        db.names.pop_back();
> +        size_t args_begin = db.names.size();
> +        while (*t != 'E')
>          {
> -            if (t == last)
> -                return first;
> -            if (db.names.empty())
> -                return first;
> -            db.names.back().first += db.names.back().second;
> -            db.names.back().second = Db::String();
> -            db.names.back().first.append("(");
> -            bool first_expr = true;
> -            while (*t != 'E')
> -            {
> -                const char* t1 = parse_expression(t, last, db);
> -                if (t1 == t || t1 == last)
> -                    return first;
> -                if (db.names.empty())
> -                    return first;
> -                auto tmp = db.names.back().move_full();
> -                db.names.pop_back();
> -                if (!tmp.empty())
> -                {
> -                    if (db.names.empty())
> -                        return first;
> -                    if (!first_expr)
> -                    {
> -                        db.names.back().first.append(", ");
> -                        first_expr = false;
> -                    }
> -                    db.names.back().first.append(tmp);
> -                }
> -                t = t1;
> -            }
> -            ++t;
> -            if (db.names.empty())
> +            const char* t1 = parse_expression(t, last, db);
> +            if (t1 == last || t1 == t)
>                  return first;
> -            db.names.back().first.append(")");
> -            first = t;
> +            t = t1;
>          }
> +        if (db.names.size() < args_begin)
> +            return first;
> +        ++t;
> +        CallExpr* the_call = db.make<CallExpr>(
> +            callee, db.popTrailingNodeArray(args_begin));
> +        db.names.push_back(the_call);
> +        first = t;
>      }
>      return first;
>  }
> @@ -1559,31 +2859,18 @@ parse_new_expr(const char* first, const
>              t += 2;
>              if (t == last)
>                  return first;
> -            bool has_expr_list = false;
> -            bool first_expr = true;
> +            size_t first_expr_in_list = db.names.size();
> +            NodeArray ExprList, init_list;
>              while (*t != '_')
>              {
>                  const char* t1 = parse_expression(t, last, db);
>                  if (t1 == t || t1 == last)
>                      return first;
> -                has_expr_list = true;
> -                if (!first_expr)
> -                {
> -                    if (db.names.empty())
> -                        return first;
> -                    auto tmp = db.names.back().move_full();
> -                    db.names.pop_back();
> -                    if (!tmp.empty())
> -                    {
> -                        if (db.names.empty())
> -                            return first;
> -                        db.names.back().first.append(", ");
> -                        db.names.back().first.append(tmp);
> -                        first_expr = false;
> -                    }
> -                }
>                  t = t1;
>              }
> +            if (first_expr_in_list < db.names.size())
> +                return first;
> +            ExprList = db.popTrailingNodeArray(first_expr_in_list);
>              ++t;
>              const char* t1 = parse_type(t, last, db);
>              if (t1 == t || t1 == last)
> @@ -1594,65 +2881,25 @@ parse_new_expr(const char* first, const
>              {
>                  t += 2;
>                  has_init = true;
> -                first_expr = true;
> +                size_t init_list_begin = db.names.size();
>                  while (*t != 'E')
>                  {
>                      t1 = parse_expression(t, last, db);
>                      if (t1 == t || t1 == last)
>                          return first;
> -                    if (!first_expr)
> -                    {
> -                        if (db.names.empty())
> -                            return first;
> -                        auto tmp = db.names.back().move_full();
> -                        db.names.pop_back();
> -                        if (!tmp.empty())
> -                        {
> -                            if (db.names.empty())
> -                                return first;
> -                            db.names.back().first.append(", ");
> -                            db.names.back().first.append(tmp);
> -                            first_expr = false;
> -                        }
> -                    }
>                      t = t1;
>                  }
> -            }
> -            if (*t != 'E')
> -                return first;
> -            Db::String init_list;
> -            if (has_init)
> -            {
> -                if (db.names.empty())
> +                if (init_list_begin < db.names.size())
>                      return first;
> -                init_list = db.names.back().move_full();
> -                db.names.pop_back();
> +                init_list = db.popTrailingNodeArray(init_list_begin);
>              }
> -            if (db.names.empty())
> +            if (*t != 'E')
>                  return first;
> -            auto type = db.names.back().move_full();
> +            auto type = db.names.back();
>              db.names.pop_back();
> -            Db::String expr_list;
> -            if (has_expr_list)
> -            {
> -                if (db.names.empty())
> -                    return first;
> -                expr_list = db.names.back().move_full();
> -                db.names.pop_back();
> -            }
> -            Db::String r;
> -            if (parsed_gs)
> -                r = "::";
> -            if (is_array)
> -                r += "[] ";
> -            else
> -                r += " ";
> -            if (has_expr_list)
> -                r += "(" + expr_list + ") ";
> -            r += type;
> -            if (has_init)
> -                r += " (" + init_list + ")";
> -            db.names.push_back(std::move(r));
> +            db.names.push_back(
> +                db.make<NewExpr>(ExprList, type, init_list,
> +                                  parsed_gs, is_array));
>              first = t+1;
>          }
>      }
> @@ -1669,10 +2916,12 @@ parse_conversion_expr(const char* first,
>      {
>          bool try_to_parse_template_args = db.try_to_parse_template_args;
>          db.try_to_parse_template_args = false;
> +        size_t type_begin = db.names.size();
>          const char* t = parse_type(first+2, last, db);
>          db.try_to_parse_template_args = try_to_parse_template_args;
>          if (t != first+2 && t != last)
>          {
> +            size_t ExprList_begin = db.names.size();
>              if (*t != '_')
>              {
>                  const char* t1 = parse_expression(t, last, db);
> @@ -1685,41 +2934,30 @@ parse_conversion_expr(const char* first,
>                  ++t;
>                  if (t == last)
>                      return first;
> -                if (*t == 'E')
> -                    db.names.emplace_back();
> -                else
> +                if (*t != 'E')
>                  {
> -                    bool first_expr = true;
>                      while (*t != 'E')
>                      {
>                          const char* t1 = parse_expression(t, last, db);
>                          if (t1 == t || t1 == last)
>                              return first;
> -                        if (!first_expr)
> -                        {
> -                            if (db.names.empty())
> -                                return first;
> -                            auto tmp = db.names.back().move_full();
> -                            db.names.pop_back();
> -                            if (!tmp.empty())
> -                            {
> -                                if (db.names.empty())
> -                                    return first;
> -                                db.names.back().first.append(", ");
> -                                db.names.back().first.append(tmp);
> -                                first_expr = false;
> -                            }
> -                        }
>                          t = t1;
>                      }
>                  }
>                  ++t;
>              }
> -            if (db.names.size() < 2)
> +            if (db.names.size() < ExprList_begin)
>                  return first;
> -            auto tmp = db.names.back().move_full();
> -            db.names.pop_back();
> -            db.names.back() = "(" + db.names.back().move_full() + ")(" +
> tmp + ")";
> +            NodeArray expressions = db.makeNodeArray(
> +                db.names.begin() + (long)ExprList_begin, db.names.end());
> +            NodeArray types = db.makeNodeArray(
> +                db.names.begin() + (long)type_begin,
> +                db.names.begin() + (long)ExprList_begin);
> +            auto* conv_expr = db.make<ConversionExpr>(
> +                types, expressions);
> +            db.names.erase(
> +                db.names.begin() + (long)type_begin, db.names.end());
> +            db.names.push_back(conv_expr);
>              first = t;
>          }
>      }
> @@ -1741,10 +2979,10 @@ parse_arrow_expr(const char* first, cons
>              {
>                  if (db.names.size() < 2)
>                      return first;
> -                auto tmp = db.names.back().move_full();
> +                auto tmp = db.names.back();
>                  db.names.pop_back();
> -                db.names.back().first += "->";
> -                db.names.back().first += tmp;
> +                db.names.back() = db.make<MemberExpr>(
> +                    db.names.back(), "->", tmp);
>                  first = t1;
>              }
>          }
> @@ -1772,11 +3010,13 @@ parse_function_type(const char* first, c
>                      return first;
>              }
>              const char* t1 = parse_type(t, last, db);
> -            if (t1 != t)
> +            if (t1 != t && !db.names.empty())
>              {
> +                Node* ret_type = db.names.back();
> +                db.names.pop_back();
> +                size_t params_begin = db.names.size();
>                  t = t1;
> -                Db::String sig("(");
> -                int ref_qual = 0;
> +                FunctionRefQual RefQuals = FrefQualNone;
>                  while (true)
>                  {
>                      if (t == last)
> @@ -1797,45 +3037,30 @@ parse_function_type(const char* first, c
>                      }
>                      if (*t == 'R' && t+1 != last && t[1] == 'E')
>                      {
> -                        ref_qual = 1;
> +                        RefQuals = FrefQualLValue;
>                          ++t;
>                          continue;
>                      }
>                      if (*t == 'O' && t+1 != last && t[1] == 'E')
>                      {
> -                        ref_qual = 2;
> +                        RefQuals = FrefQualRValue;
>                          ++t;
>                          continue;
>                      }
>                      size_t k0 = db.names.size();
>                      t1 = parse_type(t, last, db);
>                      size_t k1 = db.names.size();
> -                    if (t1 == t || t1 == last)
> +                    if (t1 == t || t1 == last || k1 < k0)
>                          return first;
> -                    for (size_t k = k0; k < k1; ++k)
> -                    {
> -                        if (sig.size() > 1)
> -                            sig += ", ";
> -                        sig += db.names[k].move_full();
> -                    }
> -                    for (size_t k = k0; k < k1; ++k)
> -                        db.names.pop_back();
>                      t = t1;
>                  }
> -                sig += ")";
> -                switch (ref_qual)
> -                {
> -                case 1:
> -                    sig += " &";
> -                    break;
> -                case 2:
> -                    sig += " &&";
> -                    break;
> -                }
>                  if (db.names.empty())
>                      return first;
> -                db.names.back().first += " ";
> -                db.names.back().second.insert(0, sig);
> +                Node* fty = db.make<FunctionType>(
> +                    ret_type, db.popTrailingNodeArray(params_begin));
> +                if (RefQuals)
> +                    fty = db.make<FunctionRefQualType>(fty, RefQuals);
> +                db.names.push_back(fty);
>                  first = t;
>              }
>          }
> @@ -1860,17 +3085,9 @@ parse_pointer_to_member_type(const char*
>                      return first;
>                  auto func = std::move(db.names.back());
>                  db.names.pop_back();
> -                auto class_type = std::move(db.names.back());
> -                if (!func.second.empty() && func.second.front() == '(')
> -                {
> -                    db.names.back().first = std::move(func.first) + "(" +
> class_type.move_full() + "::*";
> -                    db.names.back().second = ")" + std::move(func.second);
> -                }
> -                else
> -                {
> -                    db.names.back().first = std::move(func.first) + " " +
> class_type.move_full() + "::*";
> -                    db.names.back().second = std::move(func.second);
> -                }
> +                auto ClassType = std::move(db.names.back());
> +                db.names.back() =
> +                    db.make<PointerToMemberType>(ClassType, func);
>                  first = t2;
>              }
>          }
> @@ -1893,9 +3110,7 @@ parse_array_type(const char* first, cons
>              {
>                  if (db.names.empty())
>                      return first;
> -                if (db.names.back().second.substr(0, 2) == " [")
> -                    db.names.back().second.erase(0, 1);
> -                db.names.back().second.insert(0, " []");
> +                db.names.back() = db.make<ArrayType>(db.names.back());
>                  first = t;
>              }
>          }
> @@ -1909,9 +3124,9 @@ parse_array_type(const char* first, cons
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    if (db.names.back().second.substr(0, 2) == " [")
> -                        db.names.back().second.erase(0, 1);
> -                    db.names.back().second.insert(0, " [" +
> Db::String(first+1, t) + "]");
> +                    db.names.back() =
> +                        db.make<ArrayType>(db.names.back(),
> +                                            StringView(first + 1, t));
>                      first = t2;
>                  }
>              }
> @@ -1926,13 +3141,11 @@ parse_array_type(const char* first, cons
>                  {
>                      if (db.names.size() < 2)
>                          return first;
> -                    auto type = std::move(db.names.back());
> +                    auto base_type = std::move(db.names.back());
>                      db.names.pop_back();
> -                    auto expr = std::move(db.names.back());
> -                    db.names.back().first = std::move(type.first);
> -                    if (type.second.substr(0, 2) == " [")
> -                        type.second.erase(0, 1);
> -                    db.names.back().second = " [" + expr.move_full() +
> "]" + std::move(type.second);
> +                    auto dimension_expr = std::move(db.names.back());
> +                    db.names.back() =
> +                        db.make<ArrayType>(base_type, dimension_expr);
>                      first = t2;
>                  }
>              }
> @@ -1959,7 +3172,8 @@ parse_decltype(const char* first, const
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back() = "decltype(" +
> db.names.back().move_full() + ")";
> +                    db.names.back() = db.make<EnclosingExpr>(
> +                        "decltype(", db.names.back(), ")");
>                      first = t+1;
>                  }
>              }
> @@ -1997,21 +3211,24 @@ parse_vector_type(const char* first, con
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first += " vector[" +
> Db::String(num, sz) + "]";
> +                        db.names.back() =
> +                            db.make<VectorType>(db.names.back(),
> +                                                 StringView(num, num +
> sz));
>                          first = t1;
>                      }
>                  }
>                  else
>                  {
>                      ++t;
> -                    db.names.push_back("pixel vector[" + Db::String(num,
> sz) + "]");
> +                    db.names.push_back(
> +                        db.make<VectorType>(StringView(num, num + sz)));
>                      first = t;
>                  }
>              }
>          }
>          else
>          {
> -            Db::String num;
> +            Node* num = nullptr;
>              const char* t1 = first+2;
>              if (*t1 != '_')
>              {
> @@ -2020,7 +3237,7 @@ parse_vector_type(const char* first, con
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    num = db.names.back().move_full();
> +                    num = db.names.back();
>                      db.names.pop_back();
>                      t1 = t;
>                  }
> @@ -2032,9 +3249,15 @@ parse_vector_type(const char* first, con
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first += " vector[" + num + "]";
> +                    if (num)
> +                        db.names.back() =
> +                            db.make<VectorType>(db.names.back(), num);
> +                    else
> +                        db.names.back() =
> +                            db.make<VectorType>(db.names.back(),
> StringView());
>                      first = t;
> -                }
> +                } else if (num)
> +                    db.names.push_back(num);
>              }
>          }
>      }
> @@ -2050,7 +3273,7 @@ parse_vector_type(const char* first, con
>  //        ::= <template-template-param> <template-args>
>  //        ::= <decltype>
>  //        ::= <substitution>
> -//        ::= <CV-qualifiers> <type>
> +//        ::= <CV-Qualifiers> <type>
>  //        ::= P <type>        # pointer-to
>  //        ::= R <type>        # reference-to
>  //        ::= O <type>        # rvalue reference-to (C++0x)
> @@ -2075,7 +3298,7 @@ parse_type(const char* first, const char
>              case 'V':
>              case 'K':
>                {
> -                unsigned cv = 0;
> +                Qualifiers cv = QualNone;
>                  const char* t = parse_cv_qualifiers(first, last, cv);
>                  if (t != first)
>                  {
> @@ -2090,35 +3313,13 @@ parse_type(const char* first, const char
>                          db.subs.emplace_back(db.names.get_allocator());
>                          for (size_t k = k0; k < k1; ++k)
>                          {
> -                            if (is_function)
> -                            {
> -                                size_t p = db.names[k].second.size();
> -                                if (db.names[k].second[p - 2] == '&' &&
> -                                    db.names[k].second[p - 1] == '&')
> -                                    p -= 2;
> -                                else if (db.names[k].second.back() == '&')
> -                                    p -= 1;
> -                                if (cv & 1)
> -                                {
> -                                    db.names[k].second.insert(p, "
> const");
> -                                    p += 6;
> -                                }
> -                                if (cv & 2)
> -                                {
> -                                    db.names[k].second.insert(p, "
> volatile");
> -                                    p += 9;
> -                                }
> -                                if (cv & 4)
> -                                    db.names[k].second.insert(p, "
> restrict");
> -                            }
> -                            else
> -                            {
> -                                if (cv & 1)
> -                                    db.names[k].first.append(" const");
> -                                if (cv & 2)
> -                                    db.names[k].first.append(" volatile");
> -                                if (cv & 4)
> -                                    db.names[k].first.append(" restrict");
> +                            if (cv) {
> +                                if (is_function)
> +                                    db.names[k] =
> db.make<FunctionQualType>(
> +                                        db.names[k], cv);
> +                                else
> +                                    db.names[k] =
> +                                        db.make<QualType>(db.names[k],
> cv);
>                              }
>                              db.subs.back().push_back(db.names[k]);
>                          }
> @@ -2154,7 +3355,8 @@ parse_type(const char* first, const char
>                          {
>                              if (db.names.empty())
>                                  return first;
> -                            db.names.back().first.append(" complex");
> +                            db.names.back() =
> db.make<PostfixQualifiedType>(
> +                                db.names.back(), " complex");
>                              first = t;
>                              db.subs.push_back(Db::sub_type(1,
> db.names.back(), db.names.get_allocator()));
>                          }
> @@ -2175,7 +3377,8 @@ parse_type(const char* first, const char
>                          {
>                              if (db.names.empty())
>                                  return first;
> -                            db.names.back().first.append(" imaginary");
> +                            db.names.back() =
> db.make<PostfixQualifiedType>(
> +                                db.names.back(), " imaginary");
>                              first = t;
>                              db.subs.push_back(Db::sub_type(1,
> db.names.back(), db.names.get_allocator()));
>                          }
> @@ -2200,18 +3403,8 @@ parse_type(const char* first, const char
>                              db.subs.emplace_back(db.names.
> get_allocator());
>                              for (size_t k = k0; k < k1; ++k)
>                              {
> -                                if (db.names[k].second.substr(0, 2) == "
> [")
> -                                {
> -                                    db.names[k].first += " (";
> -                                    db.names[k].second.insert(0, ")");
> -                                }
> -                                else if (!db.names[k].second.empty() &&
> -                                          db.names[k].second.front() ==
> '(')
> -                                {
> -                                    db.names[k].first += "(";
> -                                    db.names[k].second.insert(0, ")");
> -                                }
> -                                db.names[k].first.append("&&");
> +                                db.names[k] =
> +                                    db.make<RValueReferenceType>(
> db.names[k]);
>                                  db.subs.back().push_back(db.names[k]);
>                              }
>                              first = t;
> @@ -2228,25 +3421,7 @@ parse_type(const char* first, const char
>                              db.subs.emplace_back(db.names.
> get_allocator());
>                              for (size_t k = k0; k < k1; ++k)
>                              {
> -                                if (db.names[k].second.substr(0, 2) == "
> [")
> -                                {
> -                                    db.names[k].first += " (";
> -                                    db.names[k].second.insert(0, ")");
> -                                }
> -                                else if (!db.names[k].second.empty() &&
> -                                          db.names[k].second.front() ==
> '(')
> -                                {
> -                                    db.names[k].first += "(";
> -                                    db.names[k].second.insert(0, ")");
> -                                }
> -                                if (first[1] != 'U' ||
> db.names[k].first.substr(0, 12) != "objc_object<")
> -                                {
> -                                    db.names[k].first.append("*");
> -                                }
> -                                else
> -                                {
> -                                    db.names[k].first.replace(0, 11,
> "id");
> -                                }
> +                                db.names[k] =
> db.make<PointerType>(db.names[k]);
>                                  db.subs.back().push_back(db.names[k]);
>                              }
>                              first = t;
> @@ -2263,18 +3438,8 @@ parse_type(const char* first, const char
>                              db.subs.emplace_back(db.names.
> get_allocator());
>                              for (size_t k = k0; k < k1; ++k)
>                              {
> -                                if (db.names[k].second.substr(0, 2) == "
> [")
> -                                {
> -                                    db.names[k].first += " (";
> -                                    db.names[k].second.insert(0, ")");
> -                                }
> -                                else if (!db.names[k].second.empty() &&
> -                                          db.names[k].second.front() ==
> '(')
> -                                {
> -                                    db.names[k].first += "(";
> -                                    db.names[k].second.insert(0, ")");
> -                                }
> -                                db.names[k].first.append("&");
> +                                db.names[k] =
> +                                    db.make<LValueReferenceType>(
> db.names[k]);
>                                  db.subs.back().push_back(db.names[k]);
>                              }
>                              first = t;
> @@ -2296,10 +3461,14 @@ parse_type(const char* first, const char
>                                  const char* t1 = parse_template_args(t,
> last, db);
>                                  if (t1 != t)
>                                  {
> -                                    auto args =
> db.names.back().move_full();
> +                                    auto args = db.names.back();
>                                      db.names.pop_back();
> -                                    db.names.back().first +=
> std::move(args);
> -                                    db.subs.push_back(Db::sub_type(1,
> db.names.back(), db.names.get_allocator()));
> +                                    db.names.back() = db.make<
> +                                        NameWithTemplateArgs>(
> +                                        db.names.back(), args);
> +                                    db.subs.push_back(Db::sub_type(
> +                                        1, db.names.back(),
> +                                        db.names.get_allocator()));
>                                      t = t1;
>                                  }
>                              }
> @@ -2318,24 +3487,25 @@ parse_type(const char* first, const char
>                                  {
>                                      if (db.names.size() < 2)
>                                          return first;
> -                                    auto type =
> db.names.back().move_full();
> +                                    auto type = db.names.back();
>                                      db.names.pop_back();
> -                                    if (db.names.back().first.substr(0,
> 9) != "objcproto")
> +                                    if (db.names.back()->K !=
> Node::KNameType ||
> +                                        !static_cast<NameType*>(db.
> names.back())->getName().startsWith("objcproto"))
>                                      {
> -                                        db.names.back() = type + " " +
> db.names.back().move_full();
> +                                        db.names.back() =
> db.make<VendorExtQualType>(type, db.names.back());
>                                      }
>                                      else
>                                      {
> -                                        auto proto =
> db.names.back().move_full();
> +                                        auto* proto =
> static_cast<NameType*>(db.names.back());
>                                          db.names.pop_back();
> -                                        t =
> parse_source_name(proto.data() + 9, proto.data() + proto.size(), db);
> -                                        if (t != proto.data() + 9)
> +                                        t = parse_source_name(proto->getName().begin()
> + 9, proto->getName().end(), db);
> +                                        if (t != proto->getName().begin()
> + 9)
>                                          {
> -                                            db.names.back() = type + "<"
> + db.names.back().move_full() + ">";
> +                                            db.names.back() =
> db.make<ObjCProtoName>(type, db.names.back());
>                                          }
>                                          else
>                                          {
> -                                            db.names.push_back(type + " "
> + proto);
> +                                            db.names.push_back(db.make<VendorExtQualType>(type,
> proto));
>                                          }
>                                      }
>                                      db.subs.push_back(Db::sub_type(1,
> db.names.back(), db.names.get_allocator()));
> @@ -2371,9 +3541,11 @@ parse_type(const char* first, const char
>                                      {
>                                          if (db.names.size() < 2)
>                                              return first;
> -                                        auto template_args =
> db.names.back().move_full();
> +                                        auto template_args =
> db.names.back();
>                                          db.names.pop_back();
> -                                        db.names.back().first +=
> template_args;
> +                                        db.names.back() = db.make<
> +                                          NameWithTemplateArgs>(
> +                                              db.names.back(),
> template_args);
>                                          // Need to create substitution
> for <template-template-param> <template-args>
>                                          db.subs.push_back(Db::sub_type(1,
> db.names.back(), db.names.get_allocator()));
>                                          first = t;
> @@ -2520,20 +3692,20 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'a':
> -                db.names.push_back("operator&&");
> +                db.names.push_back(db.make<NameType>("operator&&"));
>                  first += 2;
>                  break;
>              case 'd':
>              case 'n':
> -                db.names.push_back("operator&");
> +                db.names.push_back(db.make<NameType>("operator&"));
>                  first += 2;
>                  break;
>              case 'N':
> -                db.names.push_back("operator&=");
> +                db.names.push_back(db.make<NameType>("operator&="));
>                  first += 2;
>                  break;
>              case 'S':
> -                db.names.push_back("operator=");
> +                db.names.push_back(db.make<NameType>("operator="));
>                  first += 2;
>                  break;
>              }
> @@ -2542,15 +3714,15 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'l':
> -                db.names.push_back("operator()");
> +                db.names.push_back(db.make<NameType>("operator()"));
>                  first += 2;
>                  break;
>              case 'm':
> -                db.names.push_back("operator,");
> +                db.names.push_back(db.make<NameType>("operator,"));
>                  first += 2;
>                  break;
>              case 'o':
> -                db.names.push_back("operator~");
> +                db.names.push_back(db.make<NameType>("operator~"));
>                  first += 2;
>                  break;
>              case 'v':
> @@ -2563,7 +3735,8 @@ parse_operator_name(const char* first, c
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first.insert(0, "operator ");
> +                        db.names.back() =
> +                            db.make<ConversionOperatorType>(db.
> names.back());
>                          db.parsed_ctor_dtor_cv = true;
>                          first = t;
>                      }
> @@ -2575,23 +3748,23 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'a':
> -                db.names.push_back("operator delete[]");
> +                db.names.push_back(db.make<NameType>("operator
> delete[]"));
>                  first += 2;
>                  break;
>              case 'e':
> -                db.names.push_back("operator*");
> +                db.names.push_back(db.make<NameType>("operator*"));
>                  first += 2;
>                  break;
>              case 'l':
> -                db.names.push_back("operator delete");
> +                db.names.push_back(db.make<NameType>("operator delete"));
>                  first += 2;
>                  break;
>              case 'v':
> -                db.names.push_back("operator/");
> +                db.names.push_back(db.make<NameType>("operator/"));
>                  first += 2;
>                  break;
>              case 'V':
> -                db.names.push_back("operator/=");
> +                db.names.push_back(db.make<NameType>("operator/="));
>                  first += 2;
>                  break;
>              }
> @@ -2600,15 +3773,15 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'o':
> -                db.names.push_back("operator^");
> +                db.names.push_back(db.make<NameType>("operator^"));
>                  first += 2;
>                  break;
>              case 'O':
> -                db.names.push_back("operator^=");
> +                db.names.push_back(db.make<NameType>("operator^="));
>                  first += 2;
>                  break;
>              case 'q':
> -                db.names.push_back("operator==");
> +                db.names.push_back(db.make<NameType>("operator=="));
>                  first += 2;
>                  break;
>              }
> @@ -2617,11 +3790,11 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'e':
> -                db.names.push_back("operator>=");
> +                db.names.push_back(db.make<NameType>("operator>="));
>                  first += 2;
>                  break;
>              case 't':
> -                db.names.push_back("operator>");
> +                db.names.push_back(db.make<NameType>("operator>"));
>                  first += 2;
>                  break;
>              }
> @@ -2629,7 +3802,7 @@ parse_operator_name(const char* first, c
>          case 'i':
>              if (first[1] == 'x')
>              {
> -                db.names.push_back("operator[]");
> +                db.names.push_back(db.make<NameType>("operator[]"));
>                  first += 2;
>              }
>              break;
> @@ -2637,7 +3810,7 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'e':
> -                db.names.push_back("operator<=");
> +                db.names.push_back(db.make<NameType>("operator<="));
>                  first += 2;
>                  break;
>              case 'i':
> @@ -2647,21 +3820,22 @@ parse_operator_name(const char* first, c
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first.insert(0, "operator\"\" ");
> +                        db.names.back() =
> +                            db.make<LiteralOperator>(db.names.back());
>                          first = t;
>                      }
>                  }
>                  break;
>              case 's':
> -                db.names.push_back("operator<<");
> +                db.names.push_back(db.make<NameType>("operator<<"));
>                  first += 2;
>                  break;
>              case 'S':
> -                db.names.push_back("operator<<=");
> +                db.names.push_back(db.make<NameType>("operator<<="));
>                  first += 2;
>                  break;
>              case 't':
> -                db.names.push_back("operator<");
> +                db.names.push_back(db.make<NameType>("operator<"));
>                  first += 2;
>                  break;
>              }
> @@ -2670,23 +3844,23 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'i':
> -                db.names.push_back("operator-");
> +                db.names.push_back(db.make<NameType>("operator-"));
>                  first += 2;
>                  break;
>              case 'I':
> -                db.names.push_back("operator-=");
> +                db.names.push_back(db.make<NameType>("operator-="));
>                  first += 2;
>                  break;
>              case 'l':
> -                db.names.push_back("operator*");
> +                db.names.push_back(db.make<NameType>("operator*"));
>                  first += 2;
>                  break;
>              case 'L':
> -                db.names.push_back("operator*=");
> +                db.names.push_back(db.make<NameType>("operator*="));
>                  first += 2;
>                  break;
>              case 'm':
> -                db.names.push_back("operator--");
> +                db.names.push_back(db.make<NameType>("operator--"));
>                  first += 2;
>                  break;
>              }
> @@ -2695,23 +3869,23 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'a':
> -                db.names.push_back("operator new[]");
> +                db.names.push_back(db.make<NameType>("operator new[]"));
>                  first += 2;
>                  break;
>              case 'e':
> -                db.names.push_back("operator!=");
> +                db.names.push_back(db.make<NameType>("operator!="));
>                  first += 2;
>                  break;
>              case 'g':
> -                db.names.push_back("operator-");
> +                db.names.push_back(db.make<NameType>("operator-"));
>                  first += 2;
>                  break;
>              case 't':
> -                db.names.push_back("operator!");
> +                db.names.push_back(db.make<NameType>("operator!"));
>                  first += 2;
>                  break;
>              case 'w':
> -                db.names.push_back("operator new");
> +                db.names.push_back(db.make<NameType>("operator new"));
>                  first += 2;
>                  break;
>              }
> @@ -2720,15 +3894,15 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'o':
> -                db.names.push_back("operator||");
> +                db.names.push_back(db.make<NameType>("operator||"));
>                  first += 2;
>                  break;
>              case 'r':
> -                db.names.push_back("operator|");
> +                db.names.push_back(db.make<NameType>("operator|"));
>                  first += 2;
>                  break;
>              case 'R':
> -                db.names.push_back("operator|=");
> +                db.names.push_back(db.make<NameType>("operator|="));
>                  first += 2;
>                  break;
>              }
> @@ -2737,27 +3911,27 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'm':
> -                db.names.push_back("operator->*");
> +                db.names.push_back(db.make<NameType>("operator->*"));
>                  first += 2;
>                  break;
>              case 'l':
> -                db.names.push_back("operator+");
> +                db.names.push_back(db.make<NameType>("operator+"));
>                  first += 2;
>                  break;
>              case 'L':
> -                db.names.push_back("operator+=");
> +                db.names.push_back(db.make<NameType>("operator+="));
>                  first += 2;
>                  break;
>              case 'p':
> -                db.names.push_back("operator++");
> +                db.names.push_back(db.make<NameType>("operator++"));
>                  first += 2;
>                  break;
>              case 's':
> -                db.names.push_back("operator+");
> +                db.names.push_back(db.make<NameType>("operator+"));
>                  first += 2;
>                  break;
>              case 't':
> -                db.names.push_back("operator->");
> +                db.names.push_back(db.make<NameType>("operator->"));
>                  first += 2;
>                  break;
>              }
> @@ -2765,7 +3939,7 @@ parse_operator_name(const char* first, c
>          case 'q':
>              if (first[1] == 'u')
>              {
> -                db.names.push_back("operator?");
> +                db.names.push_back(db.make<NameType>("operator?"));
>                  first += 2;
>              }
>              break;
> @@ -2773,19 +3947,19 @@ parse_operator_name(const char* first, c
>              switch (first[1])
>              {
>              case 'm':
> -                db.names.push_back("operator%");
> +                db.names.push_back(db.make<NameType>("operator%"));
>                  first += 2;
>                  break;
>              case 'M':
> -                db.names.push_back("operator%=");
> +                db.names.push_back(db.make<NameType>("operator%="));
>                  first += 2;
>                  break;
>              case 's':
> -                db.names.push_back("operator>>");
> +                db.names.push_back(db.make<NameType>("operator>>"));
>                  first += 2;
>                  break;
>              case 'S':
> -                db.names.push_back("operator>>=");
> +                db.names.push_back(db.make<NameType>("operator>>="));
>                  first += 2;
>                  break;
>              }
> @@ -2798,7 +3972,8 @@ parse_operator_name(const char* first, c
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "operator ");
> +                    db.names.back() =
> +                        db.make<ConversionOperatorType>(db.names.back());
>                      first = t;
>                  }
>              }
> @@ -2809,23 +3984,13 @@ parse_operator_name(const char* first, c
>  }
>
>  const char*
> -parse_integer_literal(const char* first, const char* last, const
> Db::String& lit, Db& db)
> +parse_integer_literal(const char* first, const char* last, StringView
> lit, Db& db)
>  {
>      const char* t = parse_number(first, last);
>      if (t != first && t != last && *t == 'E')
>      {
> -        if (lit.size() > 3)
> -            db.names.push_back("(" + lit + ")");
> -        else
> -            db.names.emplace_back();
> -        if (*first == 'n')
> -        {
> -            db.names.back().first += '-';
> -            ++first;
> -        }
> -        db.names.back().first.append(first, t);
> -        if (lit.size() <= 3)
> -            db.names.back().first += lit;
> +        db.names.push_back(
> +            db.make<IntegerExpr>(lit, StringView(first, t)));
>          first = t+1;
>      }
>      return first;
> @@ -2858,11 +4023,11 @@ parse_expr_primary(const char* first, co
>                  switch (first[2])
>                  {
>                  case '0':
> -                    db.names.push_back("false");
> +                    db.names.push_back(db.make<BoolExpr>(0));
>                      first += 4;
>                      break;
>                  case '1':
> -                    db.names.push_back("true");
> +                    db.names.push_back(db.make<BoolExpr>(1));
>                      first += 4;
>                      break;
>                  }
> @@ -3007,7 +4172,8 @@ parse_expr_primary(const char* first, co
>                          {
>                              if (db.names.empty())
>                                  return first;
> -                            db.names.back() = "(" +
> db.names.back().move_full() + ")" + Db::String(t, n);
> +                            db.names.back() = db.make<IntegerCastExpr>(
> +                                db.names.back(), StringView(t, n));
>                              first = n+1;
>                              break;
>                          }
> @@ -3024,69 +4190,22 @@ parse_expr_primary(const char* first, co
>      return first;
>  }
>
> -template <class String>
> -String
> -base_name(String& s)
> +Node* maybe_change_special_sub_name(Node* inp, Db& db)
>  {
> -    if (s.empty())
> -        return s;
> -    if (s == "std::string")
> -    {
> -        s = "std::basic_string<char, std::char_traits<char>,
> std::allocator<char> >";
> -        return "basic_string";
> -    }
> -    if (s == "std::istream")
> -    {
> -        s = "std::basic_istream<char, std::char_traits<char> >";
> -        return "basic_istream";
> -    }
> -    if (s == "std::ostream")
> -    {
> -        s = "std::basic_ostream<char, std::char_traits<char> >";
> -        return "basic_ostream";
> -    }
> -    if (s == "std::iostream")
> -    {
> -        s = "std::basic_iostream<char, std::char_traits<char> >";
> -        return "basic_iostream";
> -    }
> -    const char* const pf = s.data();
> -    const char* pe = pf + s.size();
> -    if (pe[-1] == '>')
> -    {
> -        unsigned c = 1;
> -        while (true)
> -        {
> -            if (--pe == pf)
> -                return String();
> -            if (pe[-1] == '<')
> -            {
> -                if (--c == 0)
> -                {
> -                    --pe;
> -                    break;
> -                }
> -            }
> -            else if (pe[-1] == '>')
> -                ++c;
> -        }
> +    if (inp->K != Node::KSpecialSubstitution)
> +        return inp;
> +    auto Kind = static_cast<SpecialSubstitution*>(inp)->SSK;
> +    switch (Kind)
> +    {
> +    case SpecialSubKind::string:
> +    case SpecialSubKind::istream:
> +    case SpecialSubKind::ostream:
> +    case SpecialSubKind::iostream:
> +        return db.make<ExpandedSpecialSubstitution>(Kind);
> +    default:
> +        break;
>      }
> -    if (pe - pf <= 1)
> -      return String();
> -    const char* p0 = pe - 1;
> -    for (; p0 != pf; --p0)
> -    {
> -        if (*p0 == ':')
> -        {
> -            ++p0;
> -            break;
> -        }
> -        if (!isalpha(*p0) && !isdigit(*p0) && *p0 != '_')
> -        {
> -            return String();
> -        }
> -    }
> -    return String(p0, pe);
> +    return inp;
>  }
>
>  // <ctor-dtor-name> ::= C1    # complete object constructor
> @@ -3114,7 +4233,10 @@ parse_ctor_dtor_name(const char* first,
>              case '5':
>                  if (db.names.empty())
>                      return first;
> -                db.names.push_back(base_name(db.names.back().first));
> +                db.names.back() =
> +                    maybe_change_special_sub_name(db.names.back(), db);
> +                db.names.push_back(
> +                    db.make<CtorDtorName>(db.names.back(), false));
>                  first += 2;
>                  db.parsed_ctor_dtor_cv = true;
>                  break;
> @@ -3129,7 +4251,8 @@ parse_ctor_dtor_name(const char* first,
>              case '5':
>                  if (db.names.empty())
>                      return first;
> -                db.names.push_back("~" + base_name(db.names.back().
> first));
> +                db.names.push_back(
> +                    db.make<CtorDtorName>(db.names.back(), true));
>                  first += 2;
>                  db.parsed_ctor_dtor_cv = true;
>                  break;
> @@ -3157,106 +4280,63 @@ parse_unnamed_type_name(const char* firs
>          {
>          case 't':
>            {
> -            db.names.push_back(Db::String("'unnamed"));
>              const char* t0 = first+2;
>              if (t0 == last)
> -            {
> -                db.names.pop_back();
>                  return first;
> -            }
> +            StringView count;
>              if (std::isdigit(*t0))
>              {
>                  const char* t1 = t0 + 1;
>                  while (t1 != last && std::isdigit(*t1))
>                      ++t1;
> -                db.names.back().first.append(t0, t1);
> +                count = StringView(t0, t1);
>                  t0 = t1;
>              }
> -            db.names.back().first.push_back('\'');
>              if (t0 == last || *t0 != '_')
> -            {
> -                db.names.pop_back();
>                  return first;
> -            }
> +            db.names.push_back(db.make<UnnamedTypeName>(count));
>              first = t0 + 1;
>            }
>              break;
>          case 'l':
>            {
> -            size_t lambda_pos = db.names.size();
> -            db.names.push_back(Db::String("'lambda'("));
> +            size_t begin_pos = db.names.size();
>              const char* t0 = first+2;
> +            NodeArray lambda_params;
>              if (first[2] == 'v')
>              {
> -                db.names.back().first += ')';
>                  ++t0;
>              }
>              else
>              {
> -                bool is_first_it = true;
>                  while (true)
>                  {
> -                    long k0 = static_cast<long>(db.names.size());
>                      const char* t1 = parse_type(t0, last, db);
> -                    long k1 = static_cast<long>(db.names.size());
>                      if (t1 == t0)
>                          break;
> -                    if (k0 >= k1)
> -                        return first;
> -                    // If the call to parse_type above found a pack
> expansion
> -                    // substitution, then multiple names could have been
> -                    // inserted into the name table. Walk through the
> names,
> -                    // appending each onto the lambda's parameter list.
> -                    std::for_each(db.names.begin() + k0, db.names.begin()
> + k1,
> -                                  [&](Db::sub_type::value_type &pair) {
> -                                      if (pair.empty())
> -                                          return;
> -                                      auto &lambda =
> db.names[lambda_pos].first;
> -                                      if (!is_first_it)
> -                                          lambda.append(", ");
> -                                      is_first_it = false;
> -                                      lambda.append(pair.move_full());
> -                                  });
> -                    db.names.erase(db.names.begin() + k0,
> db.names.end());
>                      t0 = t1;
>                  }
> -                if (is_first_it)
> -                {
> -                    if (!db.names.empty())
> -                        db.names.pop_back();
> +                if (db.names.size() < begin_pos)
>                      return first;
> -                }
> -                if (db.names.empty() || db.names.size() - 1 != lambda_pos)
> -                  return first;
> -                db.names.back().first.append(")");
> +                lambda_params = db.popTrailingNodeArray(begin_pos);
>              }
>              if (t0 == last || *t0 != 'E')
> -            {
> -              if (!db.names.empty())
> -                db.names.pop_back();
> -              return first;
> -            }
> +                return first;
>              ++t0;
>              if (t0 == last)
> -            {
> -                if(!db.names.empty())
> -                  db.names.pop_back();
>                  return first;
> -            }
> +            StringView count;
>              if (std::isdigit(*t0))
>              {
>                  const char* t1 = t0 + 1;
>                  while (t1 != last && std::isdigit(*t1))
>                      ++t1;
> -                db.names.back().first.insert(
> db.names.back().first.begin()+7, t0, t1);
> +                count = StringView(t0, t1);
>                  t0 = t1;
>              }
>              if (t0 == last || *t0 != '_')
> -            {
> -                if(!db.names.empty())
> -                  db.names.pop_back();
>                  return first;
> -            }
> +            db.names.push_back(db.make<LambdaTypeName>(lambda_params,
> count));
>              first = t0 + 1;
>            }
>              break;
> @@ -3337,7 +4417,8 @@ parse_unscoped_name(const char* first, c
>              {
>                  if (db.names.empty())
>                      return first;
> -                db.names.back().first.insert(0, "std::");
> +                db.names.back() =
> +                    db.make<StdQualifiedName>(db.names.back());
>              }
>              first = t1;
>          }
> @@ -3357,7 +4438,8 @@ parse_alignof_type(const char* first, co
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back().first = "alignof (" +
> db.names.back().move_full() + ")";
> +            db.names.back() =
> +                db.make<EnclosingExpr>("alignof (", db.names.back(),
> ")");
>              first = t;
>          }
>      }
> @@ -3376,7 +4458,8 @@ parse_alignof_expr(const char* first, co
>          {
>              if (db.names.empty())
>                  return first;
> -            db.names.back().first = "alignof (" +
> db.names.back().move_full() + ")";
> +            db.names.back() =
> +                db.make<EnclosingExpr>("alignof (", db.names.back(),
> ")");
>              first = t;
>          }
>      }
> @@ -3391,28 +4474,29 @@ parse_noexcept_expression(const char* fi
>      {
>          if (db.names.empty())
>              return first;
> -        db.names.back().first =  "noexcept (" +
> db.names.back().move_full() + ")";
> +        db.names.back() =
> +            db.make<EnclosingExpr>("noexcept (", db.names.back(), ")");
>          first = t1;
>      }
>      return first;
>  }
>
>  const char*
> -parse_prefix_expression(const char* first, const char* last, const
> Db::String& op, Db& db)
> +parse_prefix_expression(const char* first, const char* last, StringView
> op, Db& db)
>  {
>      const char* t1 = parse_expression(first, last, db);
>      if (t1 != first)
>      {
>          if (db.names.empty())
>              return first;
> -        db.names.back().first =  op + "(" + db.names.back().move_full() +
> ")";
> +        db.names.back() = db.make<PrefixExpr>(op, db.names.back());
>          first = t1;
>      }
>      return first;
>  }
>
>  const char*
> -parse_binary_expression(const char* first, const char* last, const
> Db::String& op, Db& db)
> +parse_binary_expression(const char* first, const char* last, StringView
> op, Db& db)
>  {
>      const char* t1 = parse_expression(first, last, db);
>      if (t1 != first)
> @@ -3422,20 +4506,12 @@ parse_binary_expression(const char* firs
>          {
>              if (db.names.size() < 2)
>                  return first;
> -            auto op2 = db.names.back().move_full();
> +            auto op2 = db.names.back();
>              db.names.pop_back();
> -            auto op1 = db.names.back().move_full();
> -            auto& nm = db.names.back().first;
> -            nm.clear();
> -            if (op == ">")
> -                nm += '(';
> -            nm += "(" + op1 + ") " + op + " (" + op2 + ")";
> -            if (op == ">")
> -                nm += ')';
> +            auto op1 = db.names.back();
> +            db.names.back() = db.make<BinaryExpr>(op1, op, op2);
>              first = t2;
>          }
> -        else if(!db.names.empty())
> -            db.names.pop_back();
>      }
>      return first;
>  }
> @@ -3573,8 +4649,8 @@ parse_expression(const char* first, cons
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first = (parsed_gs ?
> Db::String("::") : Db::String()) +
> -                                          "delete[] " +
> db.names.back().move_full();
> +                        db.names.back() = db.make<DeleteExpr>(
> +                            db.names.back(), parsed_gs,
> /*is_array=*/true);
>                          first = t1;
>                      }
>                  }
> @@ -3594,8 +4670,8 @@ parse_expression(const char* first, cons
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first = (parsed_gs ?
> Db::String("::") : Db::String()) +
> -                                          "delete " +
> db.names.back().move_full();
> +                        db.names.back() = db.make<DeleteExpr>(
> +                            db.names.back(), parsed_gs,
> /*is_array=*/false);
>                          first = t1;
>                      }
>                  }
> @@ -3666,10 +4742,11 @@ parse_expression(const char* first, cons
>                      {
>                          if (db.names.size() < 2)
>                              return first;
> -                        auto op2 = db.names.back().move_full();
> +                        auto op2 = db.names.back();
>                          db.names.pop_back();
> -                        auto op1 = db.names.back().move_full();
> -                        db.names.back() = "(" + op1 + ")[" + op2 + "]";
> +                        auto op1 = db.names.back();
> +                        db.names.back() =
> +                            db.make<ArraySubscriptExpr>(op1, op2);
>                          first = t2;
>                      }
>                      else if (!db.names.empty())
> @@ -3739,7 +4816,8 @@ parse_expression(const char* first, cons
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back() = "(" +
> db.names.back().move_full() + ")--";
> +                        db.names.back() =
> +                            db.make<PostfixExpr>(db.names.back(), "--");
>                          first = t1;
>                      }
>                  }
> @@ -3829,7 +4907,8 @@ parse_expression(const char* first, cons
>                      {
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back() = "(" +
> db.names.back().move_full() + ")++";
> +                        db.names.back() =
> +                            db.make<PostfixExpr>(db.names.back(), "++");
>                          first = t1;
>                      }
>                  }
> @@ -3858,12 +4937,13 @@ parse_expression(const char* first, cons
>                          {
>                              if (db.names.size() < 3)
>                                  return first;
> -                            auto op3 = db.names.back().move_full();
> +                            auto op3 = db.names.back();
>                              db.names.pop_back();
> -                            auto op2 = db.names.back().move_full();
> +                            auto op2 = db.names.back();
>                              db.names.pop_back();
> -                            auto op1 = db.names.back().move_full();
> -                            db.names.back() = "(" + op1 + ") ? (" + op2 +
> ") : (" + op3 + ")";
> +                            auto op1 = db.names.back();
> +                            db.names.back() =
> +                                db.make<ConditionalExpr>(op1, op2, op3);
>                              first = t3;
>                          }
>                          else
> @@ -3948,7 +5028,7 @@ parse_expression(const char* first, cons
>                  first = parse_typeid_expr(first, last, db);
>                  break;
>              case 'r':
> -                db.names.push_back("throw");
> +                db.names.push_back(db.make<NameType>("throw"));
>                  first += 2;
>                  break;
>              case 'w':
> @@ -4037,7 +5117,7 @@ parse_template_args(const char* first, c
>          if (db.tag_templates)
>              db.template_param.back().clear();
>          const char* t = first+1;
> -        Db::String args("<");
> +        size_t begin_idx = db.names.size();
>          while (*t != 'E')
>          {
>              if (db.tag_templates)
> @@ -4047,7 +5127,7 @@ parse_template_args(const char* first, c
>              size_t k1 = db.names.size();
>              if (db.tag_templates)
>                  db.template_param.pop_back();
> -            if (t1 == t || t1 == last)
> +            if (t1 == t || t1 == last || k0 > k1)
>                  return first;
>              if (db.tag_templates)
>              {
> @@ -4055,30 +5135,18 @@ parse_template_args(const char* first, c
>                  for (size_t k = k0; k < k1; ++k)
>                      db.template_param.back().back(
> ).push_back(db.names[k]);
>              }
> -            for (size_t k = k0; k < k1; ++k)
> -            {
> -                if (args.size() > 1)
> -                    args += ", ";
> -                args += db.names[k].move_full();
> -            }
> -            for (; k1 > k0; --k1)
> -                if (!db.names.empty())
> -                    db.names.pop_back();
>              t = t1;
>          }
>          first = t + 1;
> -        if (args.back() != '>')
> -            args += ">";
> -        else
> -            args += " >";
> -        db.names.push_back(std::move(args));
> -
> +        TemplateParams* tp = db.make<TemplateParams>(
> +            db.popTrailingNodeArray(begin_idx));
> +        db.names.push_back(tp);
>      }
>      return first;
>  }
>
> -// <nested-name> ::= N [<CV-qualifiers>] [<ref-qualifier>] <prefix>
> <unqualified-name> E
> -//               ::= N [<CV-qualifiers>] [<ref-qualifier>]
> <template-prefix> <template-args> E
> +// <nested-name> ::= N [<CV-Qualifiers>] [<ref-qualifier>] <prefix>
> <unqualified-name> E
> +//               ::= N [<CV-Qualifiers>] [<ref-qualifier>]
> <template-prefix> <template-args> E
>  //
>  // <prefix> ::= <prefix> <unqualified-name>
>  //          ::= <template-prefix> <template-args>
> @@ -4099,32 +5167,29 @@ parse_nested_name(const char* first, con
>  {
>      if (first != last && *first == 'N')
>      {
> -        unsigned cv;
> +        Qualifiers cv;
>          const char* t0 = parse_cv_qualifiers(first+1, last, cv);
>          if (t0 == last)
>              return first;
> -        db.ref = 0;
> +        db.ref = FrefQualNone;
>          if (*t0 == 'R')
>          {
> -            db.ref = 1;
> +            db.ref = FrefQualLValue;
>              ++t0;
>          }
>          else if (*t0 == 'O')
>          {
> -            db.ref = 2;
> +            db.ref = FrefQualRValue;
>              ++t0;
>          }
> -        db.names.emplace_back();
> +        db.names.push_back(db.make<EmptyName>());
>          if (last - t0 >= 2 && t0[0] == 'S' && t0[1] == 't')
>          {
>              t0 += 2;
> -            db.names.back().first = "std";
> +            db.names.back() = db.make<NameType>("std");
>          }
>          if (t0 == last)
> -        {
> -            db.names.pop_back();
>              return first;
> -        }
>          bool pop_subs = false;
>          bool component_ends_with_template_args = false;
>          while (*t0 != 'E')
> @@ -4139,17 +5204,18 @@ parse_nested_name(const char* first, con
>                  t1 = parse_substitution(t0, last, db);
>                  if (t1 != t0 && t1 != last)
>                  {
> -                    auto name = db.names.back().move_full();
> +                    auto name = db.names.back();
>                      db.names.pop_back();
> -                    if (db.names.empty())
> -                        return first;
> -                    if (!db.names.back().first.empty())
> +                    if (db.names.back()->K != Node::KEmptyName)
>                      {
> -                        db.names.back().first += "::" + name;
> -                        db.subs.push_back(Db::sub_type(1,
> db.names.back(), db.names.get_allocator()));
> +                        db.names.back() = db.make<QualifiedName>(
> +                            db.names.back(), name);
> +                        db.subs.push_back(
> +                            Db::sub_type(1, db.names.back(),
> +                                         db.names.get_allocator()));
>                      }
>                      else
> -                        db.names.back().first = name;
> +                        db.names.back() = name;
>                      pop_subs = true;
>                      t0 = t1;
>                  }
> @@ -4160,14 +5226,13 @@ parse_nested_name(const char* first, con
>                  t1 = parse_template_param(t0, last, db);
>                  if (t1 != t0 && t1 != last)
>                  {
> -                    auto name = db.names.back().move_full();
> +                    auto name = db.names.back();
>                      db.names.pop_back();
> -                    if (db.names.empty())
> -                        return first;
> -                    if (!db.names.back().first.empty())
> -                        db.names.back().first += "::" + name;
> +                    if (db.names.back()->K != Node::KEmptyName)
> +                        db.names.back() =
> +                            db.make<QualifiedName>(db.names.back(),
> name);
>                      else
> -                        db.names.back().first = name;
> +                        db.names.back() = name;
>                      db.subs.push_back(Db::sub_type(1, db.names.back(),
> db.names.get_allocator()));
>                      pop_subs = true;
>                      t0 = t1;
> @@ -4181,14 +5246,13 @@ parse_nested_name(const char* first, con
>                  t1 = parse_decltype(t0, last, db);
>                  if (t1 != t0 && t1 != last)
>                  {
> -                    auto name = db.names.back().move_full();
> +                    auto name = db.names.back();
>                      db.names.pop_back();
> -                    if (db.names.empty())
> -                        return first;
> -                    if (!db.names.back().first.empty())
> -                        db.names.back().first += "::" + name;
> +                    if (db.names.back()->K != Node::KEmptyName)
> +                        db.names.back() =
> +                            db.make<QualifiedName>(db.names.back(),
> name);
>                      else
> -                        db.names.back().first = name;
> +                        db.names.back() = name;
>                      db.subs.push_back(Db::sub_type(1, db.names.back(),
> db.names.get_allocator()));
>                      pop_subs = true;
>                      t0 = t1;
> @@ -4200,12 +5264,12 @@ parse_nested_name(const char* first, con
>                  t1 = parse_template_args(t0, last, db);
>                  if (t1 != t0 && t1 != last)
>                  {
> -                    auto name = db.names.back().move_full();
> +                    auto name = db.names.back();
>                      db.names.pop_back();
> -                    if (db.names.empty())
> -                        return first;
> -                    db.names.back().first += name;
> -                    db.subs.push_back(Db::sub_type(1, db.names.back(),
> db.names.get_allocator()));
> +                    db.names.back() = db.make<NameWithTemplateArgs>(
> +                        db.names.back(), name);
> +                    db.subs.push_back(Db::sub_type(
> +                        1, db.names.back(), db.names.get_allocator()));
>                      t0 = t1;
>                      component_ends_with_template_args = true;
>                  }
> @@ -4221,14 +5285,13 @@ parse_nested_name(const char* first, con
>                  t1 = parse_unqualified_name(t0, last, db);
>                  if (t1 != t0 && t1 != last)
>                  {
> -                    auto name = db.names.back().move_full();
> +                    auto name = db.names.back();
>                      db.names.pop_back();
> -                    if (db.names.empty())
> -                        return first;
> -                    if (!db.names.back().first.empty())
> -                        db.names.back().first += "::" + name;
> +                    if (db.names.back()->K != Node::KEmptyName)
> +                        db.names.back() =
> +                            db.make<QualifiedName>(db.names.back(),
> name);
>                      else
> -                        db.names.back().first = name;
> +                        db.names.back() = name;
>                      db.subs.push_back(Db::sub_type(1, db.names.back(),
> db.names.get_allocator()));
>                      pop_subs = true;
>                      t0 = t1;
> @@ -4304,7 +5367,8 @@ parse_local_name(const char* first, cons
>                  first = parse_discriminator(t+1, last);
>                  if (db.names.empty())
>                      return first;
> -                db.names.back().first.append("::string literal");
> +                db.names.back() = db.make<QualifiedName>(
> +                    db.names.back(), db.make<NameType>("string literal"));
>                  break;
>              case 'd':
>                  if (++t != last)
> @@ -4319,12 +5383,12 @@ parse_local_name(const char* first, cons
>                          {
>                              if (db.names.size() < 2)
>                                  return first;
> -                            auto name = db.names.back().move_full();
> +                            auto name = db.names.back();
>                              db.names.pop_back();
>                              if (db.names.empty())
>                                  return first;
> -                            db.names.back().first.append("::");
> -                            db.names.back().first.append(name);
> +                            db.names.back() =
> +                                db.make<QualifiedName>(db.names.back(),
> name);
>                              first = t1;
>                          }
>                          else if (!db.names.empty())
> @@ -4342,12 +5406,12 @@ parse_local_name(const char* first, cons
>                          first = parse_discriminator(t1, last);
>                          if (db.names.size() < 2)
>                              return first;
> -                        auto name = db.names.back().move_full();
> +                        auto name = db.names.back();
>                          db.names.pop_back();
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first.append("::");
> -                        db.names.back().first.append(name);
> +                        db.names.back() =
> +                            db.make<QualifiedName>(db.names.back(),
> name);
>                      }
>                      else if (!db.names.empty())
>                          db.names.pop_back();
> @@ -4411,11 +5475,13 @@ parse_name(const char* first, const char
>                      {
>                          if (db.names.size() < 2)
>                              return first;
> -                        auto tmp = db.names.back().move_full();
> +                        auto tmp = db.names.back();
>                          db.names.pop_back();
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first += tmp;
> +                        db.names.back() =
> +                            db.make<NameWithTemplateArgs>(
> +                                db.names.back(), tmp);
>                          first = t1;
>                          if (ends_with_template_args)
>                              *ends_with_template_args = true;
> @@ -4435,11 +5501,13 @@ parse_name(const char* first, const char
>                      {
>                          if (db.names.size() < 2)
>                              return first;
> -                        auto tmp = db.names.back().move_full();
> +                        auto tmp = db.names.back();
>                          db.names.pop_back();
>                          if (db.names.empty())
>                              return first;
> -                        db.names.back().first += tmp;
> +                        db.names.back() =
> +                            db.make<NameWithTemplateArgs>(
> +                                db.names.back(), tmp);
>                          first = t1;
>                          if (ends_with_template_args)
>                              *ends_with_template_args = true;
> @@ -4527,7 +5595,8 @@ parse_special_name(const char* first, co
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "vtable for ");
> +                    db.names.back() =
> +                        db.make<SpecialName>("vtable for ",
> db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4538,7 +5607,8 @@ parse_special_name(const char* first, co
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "VTT for ");
> +                    db.names.back() =
> +                        db.make<SpecialName>("VTT for ", db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4549,7 +5619,8 @@ parse_special_name(const char* first, co
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "typeinfo for ");
> +                    db.names.back() =
> +                        db.make<SpecialName>("typeinfo for ",
> db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4560,7 +5631,8 @@ parse_special_name(const char* first, co
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "typeinfo name for
> ");
> +                    db.names.back() =
> +                        db.make<SpecialName>("typeinfo name for ",
> db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4578,7 +5650,9 @@ parse_special_name(const char* first, co
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "covariant return
> thunk to ");
> +                    db.names.back() =
> +                        db.make<SpecialName>("covariant return thunk to
> ",
> +                                              db.names.back());
>                      first = t;
>                  }
>                }
> @@ -4596,13 +5670,12 @@ parse_special_name(const char* first, co
>                          {
>                              if (db.names.size() < 2)
>                                  return first;
> -                            auto left = db.names.back().move_full();
> +                            auto left = db.names.back();
>                              db.names.pop_back();
>                              if (db.names.empty())
>                                  return first;
> -                            db.names.back().first = "construction vtable
> for " +
> -                                                    std::move(left) +
> "-in-" +
> -
> db.names.back().move_full();
> +                            db.names.back() =
> db.make<CtorVtableSpecialName>(
> +                                left, db.names.back());
>                              first = t1;
>                          }
>                      }
> @@ -4614,8 +5687,10 @@ parse_special_name(const char* first, co
>                  if (t != first + 2)
>                  {
>                      if (db.names.empty())
> -                    return first;
> -                    db.names.back().first.insert(0, "thread-local
> wrapper routine for ");
> +                        return first;
> +                    db.names.back() =
> +                        db.make<SpecialName>("thread-local wrapper
> routine for ",
> +                                              db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4625,8 +5700,9 @@ parse_special_name(const char* first, co
>                  if (t != first + 2)
>                  {
>                      if (db.names.empty())
> -                    return first;
> -                    db.names.back().first.insert(0, "thread-local
> initialization routine for ");
> +                        return first;
> +                    db.names.back() = db.make<SpecialName>(
> +                        "thread-local initialization routine for ",
> db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4643,12 +5719,16 @@ parse_special_name(const char* first, co
>                          return first;
>                      if (first[1] == 'v')
>                      {
> -                        db.names.back().first.insert(0, "virtual thunk
> to ");
> +                        db.names.back() =
> +                            db.make<SpecialName>("virtual thunk to ",
> +                                                  db.names.back());
>                          first = t;
>                      }
>                      else
>                      {
> -                        db.names.back().first.insert(0, "non-virtual
> thunk to ");
> +                        db.names.back() =
> +                            db.make<SpecialName>("non-virtual thunk to ",
> +                                                  db.names.back());
>                          first = t;
>                      }
>                  }
> @@ -4666,7 +5746,8 @@ parse_special_name(const char* first, co
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "guard variable for
> ");
> +                    db.names.back() =
> +                        db.make<SpecialName>("guard variable for ",
> db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4677,7 +5758,9 @@ parse_special_name(const char* first, co
>                  {
>                      if (db.names.empty())
>                          return first;
> -                    db.names.back().first.insert(0, "reference temporary
> for ");
> +                    db.names.back() =
> +                        db.make<SpecialName>("reference temporary for ",
> +                                              db.names.back());
>                      first = t;
>                  }
>                  break;
> @@ -4735,8 +5818,10 @@ parse_encoding(const char* first, const
>              bool ends_with_template_args = false;
>              const char* t = parse_name(first, last, db,
>                                         &ends_with_template_args);
> -            unsigned cv = db.cv;
> -            unsigned ref = db.ref;
> +            if (db.names.empty())
> +                return first;
> +            Qualifiers cv = db.cv;
> +            FunctionRefQual ref = db.ref;
>              if (t != first)
>              {
>                  if (t != last && *t != 'E' && *t != '.')
> @@ -4744,87 +5829,59 @@ parse_encoding(const char* first, const
>                      save_value<bool> sb2(db.tag_templates);
>                      db.tag_templates = false;
>                      const char* t2;
> -                    Db::String ret2;
>                      if (db.names.empty())
>                          return first;
> -                    const Db::String& nm = db.names.back().first;
> -                    if (nm.empty())
> +                    if (!db.names.back())
>                          return first;
> +                    Node* return_type = nullptr;
>                      if (!db.parsed_ctor_dtor_cv &&
> ends_with_template_args)
>                      {
>                          t2 = parse_type(t, last, db);
>                          if (t2 == t)
>                              return first;
> -                        if (db.names.size() < 2)
> +                        if (db.names.size() < 1)
>                              return first;
> -                        auto ret1 = std::move(db.names.back().first);
> -                        ret2 = std::move(db.names.back().second);
> -                        if (ret2.empty())
> -                            ret1 += ' ';
> +                        return_type = db.names.back();
>                          db.names.pop_back();
> -                        if (db.names.empty())
> -                            return first;
> -
> -                        db.names.back().first.insert(0, ret1);
>                          t = t2;
>                      }
> -                    db.names.back().first += '(';
> +
> +                    Node* result = nullptr;
> +
>                      if (t != last && *t == 'v')
>                      {
>                          ++t;
> +                        Node* name = db.names.back();
> +                        db.names.pop_back();
> +                        result = db.make<TopLevelFunctionDecl>(
> +                            return_type, name, NodeArray());
>                      }
>                      else
>                      {
> -                        bool first_arg = true;
> +                        size_t params_begin = db.names.size();
>                          while (true)
>                          {
> -                            size_t k0 = db.names.size();
>                              t2 = parse_type(t, last, db);
> -                            size_t k1 = db.names.size();
>                              if (t2 == t)
>                                  break;
> -                            if (k1 > k0)
> -                            {
> -                                Db::String tmp;
> -                                for (size_t k = k0; k < k1; ++k)
> -                                {
> -                                    if (!tmp.empty())
> -                                        tmp += ", ";
> -                                    tmp += db.names[k].move_full();
> -                                }
> -                                for (size_t k = k0; k < k1; ++k) {
> -                                    if (db.names.empty())
> -                                        return first;
> -                                    db.names.pop_back();
> -                                }
> -                                if (!tmp.empty())
> -                                {
> -                                    if (db.names.empty())
> -                                        return first;
> -                                    if (!first_arg)
> -                                        db.names.back().first += ", ";
> -                                    else
> -                                        first_arg = false;
> -                                    db.names.back().first += tmp;
> -                                }
> -                            }
>                              t = t2;
>                          }
> +                        if (db.names.size() < params_begin)
> +                            return first;
> +                        NodeArray params =
> +                            db.popTrailingNodeArray(params_begin);
> +                        if (db.names.empty())
> +                            return first;
> +                        Node* name = db.names.back();
> +                        db.names.pop_back();
> +                        result = db.make<TopLevelFunctionDecl>(
> +                            return_type, name, params);
>                      }
> -                    if (db.names.empty())
> -                        return first;
> -                    db.names.back().first += ')';
> -                    if (cv & 1)
> -                        db.names.back().first.append(" const");
> -                    if (cv & 2)
> -                        db.names.back().first.append(" volatile");
> -                    if (cv & 4)
> -                        db.names.back().first.append(" restrict");
> -                    if (ref == 1)
> -                        db.names.back().first.append(" &");
> -                    else if (ref == 2)
> -                        db.names.back().first.append(" &&");
> -                    db.names.back().first += ret2;
> +                    if (ref != FrefQualNone)
> +                        result = db.make<FunctionRefQualType>(result,
> ref);
> +                    if (cv != QualNone)
> +                        result = db.make<FunctionQualType>(result, cv);
> +                    db.names.push_back(result);
>                      first = t;
>                  }
>                  else
> @@ -4846,6 +5903,7 @@ parse_block_invoke(const char* first, co
>  {
>      if (last - first >= 13)
>      {
> +        // FIXME: strcmp?
>          const char test[] = "_block_invoke";
>          const char* t = first;
>          for (int i = 0; i < 13; ++i, ++t)
> @@ -4868,7 +5926,9 @@ parse_block_invoke(const char* first, co
>          }
>          if (db.names.empty())
>              return first;
> -        db.names.back().first.insert(0, "invocation function for block
> in ");
> +        db.names.back() =
> +            db.make<SpecialName>("invocation function for block in ",
> +                                  db.names.back());
>          first = t;
>      }
>      return first;
> @@ -4884,7 +5944,8 @@ parse_dot_suffix(const char* first, cons
>      {
>          if (db.names.empty())
>              return first;
> -        db.names.back().first += " (" + Db::String(first, last) + ")";
> +        db.names.back() =
> +            db.make<DotSuffix>(db.names.back(), StringView(first, last));
>          first = last;
>      }
>      return first;
> @@ -4963,6 +6024,7 @@ __cxa_demangle(const char *mangled_name,
>      size_t len = std::strlen(mangled_name);
>      demangle(mangled_name, mangled_name + len, db,
>               internal_status);
> +
>      if (internal_status == success && db.fix_forward_references &&
>             !db.template_param.empty() && !db.template_param.front().
> empty())
>      {
> @@ -4974,30 +6036,25 @@ __cxa_demangle(const char *mangled_name,
>          if (db.fix_forward_references)
>              internal_status = invalid_mangled_name;
>      }
> +
>      if (internal_status == success)
>      {
> -        size_t sz = db.names.back().size() + 1;
> -        if (sz > internal_size)
> +        if (!buf)
>          {
> -            char* newbuf = static_cast<char*>(std::realloc(buf, sz));
> -            if (newbuf == nullptr)
> -            {
> -                internal_status = memory_alloc_failure;
> -                buf = nullptr;
> -            }
> -            else
> -            {
> -                buf = newbuf;
> -                if (n != nullptr)
> -                    *n = sz;
> -            }
> +            internal_size = 1024;
> +            buf = static_cast<char*>(std::malloc(internal_size));
>          }
> -        if (buf != nullptr)
> +
> +        if (buf)
>          {
> -            db.names.back().first += db.names.back().second;
> -            std::memcpy(buf, db.names.back().first.data(), sz-1);
> -            buf[sz-1] = char(0);
> +            OutputStream s(buf, internal_size);
> +            db.names.back()->print(s);
> +            s += '\0';
> +            if (n) *n = s.getCurrentPosition();
> +            buf = s.getBuffer();
>          }
> +        else
> +            internal_status = memory_alloc_failure;
>      }
>      else
>          buf = nullptr;
>
> Modified: libcxxabi/trunk/test/test_demangle.pass.cpp
> URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/test/
> test_demangle.pass.cpp?rev=309340&r1=309339&r2=309340&view=diff
> ============================================================
> ==================
> --- libcxxabi/trunk/test/test_demangle.pass.cpp (original)
> +++ libcxxabi/trunk/test/test_demangle.pass.cpp Thu Jul 27 17:43:49 2017
> @@ -29600,8 +29600,7 @@ const char* cases[][2] =
>      {"i", "int"},
>
>      {"PKFvRiE", "void (*)(int&) const"},
> -    // FIXME(compnerd) pretty print this as void (*)(unsigned long &)
> volatile &&
> -    {"PVFvRmOE", "void (*)(unsigned long&)  volatile&&"},
> +    {"PVFvRmOE", "void (*)(unsigned long&) volatile &&"},
>      {"PFvRmOE", "void (*)(unsigned long&) &&"},
>      {"_ZTW1x", "thread-local wrapper routine for x"},
>      {"_ZTHN3fooE", "thread-local initialization routine for foo"},
>
>
> _______________________________________________
> cfe-commits mailing list
> cfe-commits at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>
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