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diff --git a/linux-x64/clang/include/llvm/CodeGen/DIE.h b/linux-x64/clang/include/llvm/CodeGen/DIE.h
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+//===- lib/CodeGen/DIE.h - DWARF Info Entries -------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Data structures for DWARF info entries.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DIE_H
+#define LLVM_LIB_CODEGEN_ASMPRINTER_DIE_H
+
+#include "llvm/ADT/FoldingSet.h"
+#include "llvm/ADT/PointerIntPair.h"
+#include "llvm/ADT/PointerUnion.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/iterator.h"
+#include "llvm/ADT/iterator_range.h"
+#include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/CodeGen/DwarfStringPoolEntry.h"
+#include "llvm/Support/AlignOf.h"
+#include "llvm/Support/Allocator.h"
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <iterator>
+#include <new>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+namespace llvm {
+
+class AsmPrinter;
+class DIE;
+class DIEUnit;
+class MCExpr;
+class MCSection;
+class MCSymbol;
+class raw_ostream;
+
+//===--------------------------------------------------------------------===//
+/// Dwarf abbreviation data, describes one attribute of a Dwarf abbreviation.
+class DIEAbbrevData {
+  /// Dwarf attribute code.
+  dwarf::Attribute Attribute;
+
+  /// Dwarf form code.
+  dwarf::Form Form;
+
+  /// Dwarf attribute value for DW_FORM_implicit_const
+  int64_t Value = 0;
+
+public:
+  DIEAbbrevData(dwarf::Attribute A, dwarf::Form F)
+      : Attribute(A), Form(F) {}
+  DIEAbbrevData(dwarf::Attribute A, int64_t V)
+      : Attribute(A), Form(dwarf::DW_FORM_implicit_const), Value(V) {}
+
+  /// Accessors.
+  /// @{
+  dwarf::Attribute getAttribute() const { return Attribute; }
+  dwarf::Form getForm() const { return Form; }
+  int64_t getValue() const { return Value; }
+  /// @}
+
+  /// Used to gather unique data for the abbreviation folding set.
+  void Profile(FoldingSetNodeID &ID) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// Dwarf abbreviation, describes the organization of a debug information
+/// object.
+class DIEAbbrev : public FoldingSetNode {
+  /// Unique number for node.
+  unsigned Number;
+
+  /// Dwarf tag code.
+  dwarf::Tag Tag;
+
+  /// Whether or not this node has children.
+  ///
+  /// This cheats a bit in all of the uses since the values in the standard
+  /// are 0 and 1 for no children and children respectively.
+  bool Children;
+
+  /// Raw data bytes for abbreviation.
+  SmallVector<DIEAbbrevData, 12> Data;
+
+public:
+  DIEAbbrev(dwarf::Tag T, bool C) : Tag(T), Children(C) {}
+
+  /// Accessors.
+  /// @{
+  dwarf::Tag getTag() const { return Tag; }
+  unsigned getNumber() const { return Number; }
+  bool hasChildren() const { return Children; }
+  const SmallVectorImpl<DIEAbbrevData> &getData() const { return Data; }
+  void setChildrenFlag(bool hasChild) { Children = hasChild; }
+  void setNumber(unsigned N) { Number = N; }
+  /// @}
+
+  /// Adds another set of attribute information to the abbreviation.
+  void AddAttribute(dwarf::Attribute Attribute, dwarf::Form Form) {
+    Data.push_back(DIEAbbrevData(Attribute, Form));
+  }
+
+  /// Adds attribute with DW_FORM_implicit_const value
+  void AddImplicitConstAttribute(dwarf::Attribute Attribute, int64_t Value) {
+    Data.push_back(DIEAbbrevData(Attribute, Value));
+  }
+
+  /// Used to gather unique data for the abbreviation folding set.
+  void Profile(FoldingSetNodeID &ID) const;
+
+  /// Print the abbreviation using the specified asm printer.
+  void Emit(const AsmPrinter *AP) const;
+
+  void print(raw_ostream &O) const;
+  void dump() const;
+};
+
+//===--------------------------------------------------------------------===//
+/// Helps unique DIEAbbrev objects and assigns abbreviation numbers.
+///
+/// This class will unique the DIE abbreviations for a llvm::DIE object and
+/// assign a unique abbreviation number to each unique DIEAbbrev object it
+/// finds. The resulting collection of DIEAbbrev objects can then be emitted
+/// into the .debug_abbrev section.
+class DIEAbbrevSet {
+  /// The bump allocator to use when creating DIEAbbrev objects in the uniqued
+  /// storage container.
+  BumpPtrAllocator &Alloc;
+  /// \brief FoldingSet that uniques the abbreviations.
+  FoldingSet<DIEAbbrev> AbbreviationsSet;
+  /// A list of all the unique abbreviations in use.
+  std::vector<DIEAbbrev *> Abbreviations;
+
+public:
+  DIEAbbrevSet(BumpPtrAllocator &A) : Alloc(A) {}
+  ~DIEAbbrevSet();
+
+  /// Generate the abbreviation declaration for a DIE and return a pointer to
+  /// the generated abbreviation.
+  ///
+  /// \param Die the debug info entry to generate the abbreviation for.
+  /// \returns A reference to the uniqued abbreviation declaration that is
+  /// owned by this class.
+  DIEAbbrev &uniqueAbbreviation(DIE &Die);
+
+  /// Print all abbreviations using the specified asm printer.
+  void Emit(const AsmPrinter *AP, MCSection *Section) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// An integer value DIE.
+///
+class DIEInteger {
+  uint64_t Integer;
+
+public:
+  explicit DIEInteger(uint64_t I) : Integer(I) {}
+
+  /// Choose the best form for integer.
+  static dwarf::Form BestForm(bool IsSigned, uint64_t Int) {
+    if (IsSigned) {
+      const int64_t SignedInt = Int;
+      if ((char)Int == SignedInt)
+        return dwarf::DW_FORM_data1;
+      if ((short)Int == SignedInt)
+        return dwarf::DW_FORM_data2;
+      if ((int)Int == SignedInt)
+        return dwarf::DW_FORM_data4;
+    } else {
+      if ((unsigned char)Int == Int)
+        return dwarf::DW_FORM_data1;
+      if ((unsigned short)Int == Int)
+        return dwarf::DW_FORM_data2;
+      if ((unsigned int)Int == Int)
+        return dwarf::DW_FORM_data4;
+    }
+    return dwarf::DW_FORM_data8;
+  }
+
+  uint64_t getValue() const { return Integer; }
+  void setValue(uint64_t Val) { Integer = Val; }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// An expression DIE.
+class DIEExpr {
+  const MCExpr *Expr;
+
+public:
+  explicit DIEExpr(const MCExpr *E) : Expr(E) {}
+
+  /// Get MCExpr.
+  const MCExpr *getValue() const { return Expr; }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// A label DIE.
+class DIELabel {
+  const MCSymbol *Label;
+
+public:
+  explicit DIELabel(const MCSymbol *L) : Label(L) {}
+
+  /// Get MCSymbol.
+  const MCSymbol *getValue() const { return Label; }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// A simple label difference DIE.
+///
+class DIEDelta {
+  const MCSymbol *LabelHi;
+  const MCSymbol *LabelLo;
+
+public:
+  DIEDelta(const MCSymbol *Hi, const MCSymbol *Lo) : LabelHi(Hi), LabelLo(Lo) {}
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// A container for string pool string values.
+///
+/// This class is used with the DW_FORM_strp and DW_FORM_GNU_str_index forms.
+class DIEString {
+  DwarfStringPoolEntryRef S;
+
+public:
+  DIEString(DwarfStringPoolEntryRef S) : S(S) {}
+
+  /// Grab the string out of the object.
+  StringRef getString() const { return S.getString(); }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// A container for inline string values.
+///
+/// This class is used with the DW_FORM_string form.
+class DIEInlineString {
+  StringRef S;
+
+public:
+  template <typename Allocator>
+  explicit DIEInlineString(StringRef Str, Allocator &A) : S(Str.copy(A)) {}
+
+  ~DIEInlineString() = default;
+
+  /// Grab the string out of the object.
+  StringRef getString() const { return S; }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// A pointer to another debug information entry.  An instance of this class can
+/// also be used as a proxy for a debug information entry not yet defined
+/// (ie. types.)
+class DIEEntry {
+  DIE *Entry;
+
+public:
+  DIEEntry() = delete;
+  explicit DIEEntry(DIE &E) : Entry(&E) {}
+
+  DIE &getEntry() const { return *Entry; }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// Represents a pointer to a location list in the debug_loc
+/// section.
+class DIELocList {
+  /// Index into the .debug_loc vector.
+  size_t Index;
+
+public:
+  DIELocList(size_t I) : Index(I) {}
+
+  /// Grab the current index out.
+  size_t getValue() const { return Index; }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// A debug information entry value. Some of these roughly correlate
+/// to DWARF attribute classes.
+class DIEBlock;
+class DIELoc;
+class DIEValue {
+public:
+  enum Type {
+    isNone,
+#define HANDLE_DIEVALUE(T) is##T,
+#include "llvm/CodeGen/DIEValue.def"
+  };
+
+private:
+  /// Type of data stored in the value.
+  Type Ty = isNone;
+  dwarf::Attribute Attribute = (dwarf::Attribute)0;
+  dwarf::Form Form = (dwarf::Form)0;
+
+  /// Storage for the value.
+  ///
+  /// All values that aren't standard layout (or are larger than 8 bytes)
+  /// should be stored by reference instead of by value.
+  using ValTy = AlignedCharArrayUnion<DIEInteger, DIEString, DIEExpr, DIELabel,
+                                      DIEDelta *, DIEEntry, DIEBlock *,
+                                      DIELoc *, DIELocList>;
+
+  static_assert(sizeof(ValTy) <= sizeof(uint64_t) ||
+                    sizeof(ValTy) <= sizeof(void *),
+                "Expected all large types to be stored via pointer");
+
+  /// Underlying stored value.
+  ValTy Val;
+
+  template <class T> void construct(T V) {
+    static_assert(std::is_standard_layout<T>::value ||
+                      std::is_pointer<T>::value,
+                  "Expected standard layout or pointer");
+    new (reinterpret_cast<void *>(Val.buffer)) T(V);
+  }
+
+  template <class T> T *get() { return reinterpret_cast<T *>(Val.buffer); }
+  template <class T> const T *get() const {
+    return reinterpret_cast<const T *>(Val.buffer);
+  }
+  template <class T> void destruct() { get<T>()->~T(); }
+
+  /// Destroy the underlying value.
+  ///
+  /// This should get optimized down to a no-op.  We could skip it if we could
+  /// add a static assert on \a std::is_trivially_copyable(), but we currently
+  /// support versions of GCC that don't understand that.
+  void destroyVal() {
+    switch (Ty) {
+    case isNone:
+      return;
+#define HANDLE_DIEVALUE_SMALL(T)                                               \
+  case is##T:                                                                  \
+    destruct<DIE##T>();                                                        \
+    return;
+#define HANDLE_DIEVALUE_LARGE(T)                                               \
+  case is##T:                                                                  \
+    destruct<const DIE##T *>();                                                \
+    return;
+#include "llvm/CodeGen/DIEValue.def"
+    }
+  }
+
+  /// Copy the underlying value.
+  ///
+  /// This should get optimized down to a simple copy.  We need to actually
+  /// construct the value, rather than calling memcpy, to satisfy strict
+  /// aliasing rules.
+  void copyVal(const DIEValue &X) {
+    switch (Ty) {
+    case isNone:
+      return;
+#define HANDLE_DIEVALUE_SMALL(T)                                               \
+  case is##T:                                                                  \
+    construct<DIE##T>(*X.get<DIE##T>());                                       \
+    return;
+#define HANDLE_DIEVALUE_LARGE(T)                                               \
+  case is##T:                                                                  \
+    construct<const DIE##T *>(*X.get<const DIE##T *>());                       \
+    return;
+#include "llvm/CodeGen/DIEValue.def"
+    }
+  }
+
+public:
+  DIEValue() = default;
+
+  DIEValue(const DIEValue &X) : Ty(X.Ty), Attribute(X.Attribute), Form(X.Form) {
+    copyVal(X);
+  }
+
+  DIEValue &operator=(const DIEValue &X) {
+    destroyVal();
+    Ty = X.Ty;
+    Attribute = X.Attribute;
+    Form = X.Form;
+    copyVal(X);
+    return *this;
+  }
+
+  ~DIEValue() { destroyVal(); }
+
+#define HANDLE_DIEVALUE_SMALL(T)                                               \
+  DIEValue(dwarf::Attribute Attribute, dwarf::Form Form, const DIE##T &V)      \
+      : Ty(is##T), Attribute(Attribute), Form(Form) {                          \
+    construct<DIE##T>(V);                                                      \
+  }
+#define HANDLE_DIEVALUE_LARGE(T)                                               \
+  DIEValue(dwarf::Attribute Attribute, dwarf::Form Form, const DIE##T *V)      \
+      : Ty(is##T), Attribute(Attribute), Form(Form) {                          \
+    assert(V && "Expected valid value");                                       \
+    construct<const DIE##T *>(V);                                              \
+  }
+#include "llvm/CodeGen/DIEValue.def"
+
+  /// Accessors.
+  /// @{
+  Type getType() const { return Ty; }
+  dwarf::Attribute getAttribute() const { return Attribute; }
+  dwarf::Form getForm() const { return Form; }
+  explicit operator bool() const { return Ty; }
+  /// @}
+
+#define HANDLE_DIEVALUE_SMALL(T)                                               \
+  const DIE##T &getDIE##T() const {                                            \
+    assert(getType() == is##T && "Expected " #T);                              \
+    return *get<DIE##T>();                                                     \
+  }
+#define HANDLE_DIEVALUE_LARGE(T)                                               \
+  const DIE##T &getDIE##T() const {                                            \
+    assert(getType() == is##T && "Expected " #T);                              \
+    return **get<const DIE##T *>();                                            \
+  }
+#include "llvm/CodeGen/DIEValue.def"
+
+  /// Emit value via the Dwarf writer.
+  void EmitValue(const AsmPrinter *AP) const;
+
+  /// Return the size of a value in bytes.
+  unsigned SizeOf(const AsmPrinter *AP) const;
+
+  void print(raw_ostream &O) const;
+  void dump() const;
+};
+
+struct IntrusiveBackListNode {
+  PointerIntPair<IntrusiveBackListNode *, 1> Next;
+
+  IntrusiveBackListNode() : Next(this, true) {}
+
+  IntrusiveBackListNode *getNext() const {
+    return Next.getInt() ? nullptr : Next.getPointer();
+  }
+};
+
+struct IntrusiveBackListBase {
+  using Node = IntrusiveBackListNode;
+
+  Node *Last = nullptr;
+
+  bool empty() const { return !Last; }
+
+  void push_back(Node &N) {
+    assert(N.Next.getPointer() == &N && "Expected unlinked node");
+    assert(N.Next.getInt() == true && "Expected unlinked node");
+
+    if (Last) {
+      N.Next = Last->Next;
+      Last->Next.setPointerAndInt(&N, false);
+    }
+    Last = &N;
+  }
+};
+
+template <class T> class IntrusiveBackList : IntrusiveBackListBase {
+public:
+  using IntrusiveBackListBase::empty;
+
+  void push_back(T &N) { IntrusiveBackListBase::push_back(N); }
+  T &back() { return *static_cast<T *>(Last); }
+  const T &back() const { return *static_cast<T *>(Last); }
+
+  class const_iterator;
+  class iterator
+      : public iterator_facade_base<iterator, std::forward_iterator_tag, T> {
+    friend class const_iterator;
+
+    Node *N = nullptr;
+
+  public:
+    iterator() = default;
+    explicit iterator(T *N) : N(N) {}
+
+    iterator &operator++() {
+      N = N->getNext();
+      return *this;
+    }
+
+    explicit operator bool() const { return N; }
+    T &operator*() const { return *static_cast<T *>(N); }
+
+    bool operator==(const iterator &X) const { return N == X.N; }
+    bool operator!=(const iterator &X) const { return N != X.N; }
+  };
+
+  class const_iterator
+      : public iterator_facade_base<const_iterator, std::forward_iterator_tag,
+                                    const T> {
+    const Node *N = nullptr;
+
+  public:
+    const_iterator() = default;
+    // Placate MSVC by explicitly scoping 'iterator'.
+    const_iterator(typename IntrusiveBackList<T>::iterator X) : N(X.N) {}
+    explicit const_iterator(const T *N) : N(N) {}
+
+    const_iterator &operator++() {
+      N = N->getNext();
+      return *this;
+    }
+
+    explicit operator bool() const { return N; }
+    const T &operator*() const { return *static_cast<const T *>(N); }
+
+    bool operator==(const const_iterator &X) const { return N == X.N; }
+    bool operator!=(const const_iterator &X) const { return N != X.N; }
+  };
+
+  iterator begin() {
+    return Last ? iterator(static_cast<T *>(Last->Next.getPointer())) : end();
+  }
+  const_iterator begin() const {
+    return const_cast<IntrusiveBackList *>(this)->begin();
+  }
+  iterator end() { return iterator(); }
+  const_iterator end() const { return const_iterator(); }
+
+  static iterator toIterator(T &N) { return iterator(&N); }
+  static const_iterator toIterator(const T &N) { return const_iterator(&N); }
+};
+
+/// A list of DIE values.
+///
+/// This is a singly-linked list, but instead of reversing the order of
+/// insertion, we keep a pointer to the back of the list so we can push in
+/// order.
+///
+/// There are two main reasons to choose a linked list over a customized
+/// vector-like data structure.
+///
+///  1. For teardown efficiency, we want DIEs to be BumpPtrAllocated.  Using a
+///     linked list here makes this way easier to accomplish.
+///  2. Carrying an extra pointer per \a DIEValue isn't expensive.  45% of DIEs
+///     have 2 or fewer values, and 90% have 5 or fewer.  A vector would be
+///     over-allocated by 50% on average anyway, the same cost as the
+///     linked-list node.
+class DIEValueList {
+  struct Node : IntrusiveBackListNode {
+    DIEValue V;
+
+    explicit Node(DIEValue V) : V(V) {}
+  };
+
+  using ListTy = IntrusiveBackList<Node>;
+
+  ListTy List;
+
+public:
+  class const_value_iterator;
+  class value_iterator
+      : public iterator_adaptor_base<value_iterator, ListTy::iterator,
+                                     std::forward_iterator_tag, DIEValue> {
+    friend class const_value_iterator;
+
+    using iterator_adaptor =
+        iterator_adaptor_base<value_iterator, ListTy::iterator,
+                              std::forward_iterator_tag, DIEValue>;
+
+  public:
+    value_iterator() = default;
+    explicit value_iterator(ListTy::iterator X) : iterator_adaptor(X) {}
+
+    explicit operator bool() const { return bool(wrapped()); }
+    DIEValue &operator*() const { return wrapped()->V; }
+  };
+
+  class const_value_iterator : public iterator_adaptor_base<
+                                   const_value_iterator, ListTy::const_iterator,
+                                   std::forward_iterator_tag, const DIEValue> {
+    using iterator_adaptor =
+        iterator_adaptor_base<const_value_iterator, ListTy::const_iterator,
+                              std::forward_iterator_tag, const DIEValue>;
+
+  public:
+    const_value_iterator() = default;
+    const_value_iterator(DIEValueList::value_iterator X)
+        : iterator_adaptor(X.wrapped()) {}
+    explicit const_value_iterator(ListTy::const_iterator X)
+        : iterator_adaptor(X) {}
+
+    explicit operator bool() const { return bool(wrapped()); }
+    const DIEValue &operator*() const { return wrapped()->V; }
+  };
+
+  using value_range = iterator_range<value_iterator>;
+  using const_value_range = iterator_range<const_value_iterator>;
+
+  value_iterator addValue(BumpPtrAllocator &Alloc, const DIEValue &V) {
+    List.push_back(*new (Alloc) Node(V));
+    return value_iterator(ListTy::toIterator(List.back()));
+  }
+  template <class T>
+  value_iterator addValue(BumpPtrAllocator &Alloc, dwarf::Attribute Attribute,
+                    dwarf::Form Form, T &&Value) {
+    return addValue(Alloc, DIEValue(Attribute, Form, std::forward<T>(Value)));
+  }
+
+  value_range values() {
+    return make_range(value_iterator(List.begin()), value_iterator(List.end()));
+  }
+  const_value_range values() const {
+    return make_range(const_value_iterator(List.begin()),
+                      const_value_iterator(List.end()));
+  }
+};
+
+//===--------------------------------------------------------------------===//
+/// A structured debug information entry.  Has an abbreviation which
+/// describes its organization.
+class DIE : IntrusiveBackListNode, public DIEValueList {
+  friend class IntrusiveBackList<DIE>;
+  friend class DIEUnit;
+
+  /// Dwarf unit relative offset.
+  unsigned Offset = 0;
+  /// Size of instance + children.
+  unsigned Size = 0;
+  unsigned AbbrevNumber = ~0u;
+  /// Dwarf tag code.
+  dwarf::Tag Tag = (dwarf::Tag)0;
+  /// Set to true to force a DIE to emit an abbreviation that says it has
+  /// children even when it doesn't. This is used for unit testing purposes.
+  bool ForceChildren = false;
+  /// Children DIEs.
+  IntrusiveBackList<DIE> Children;
+
+  /// The owner is either the parent DIE for children of other DIEs, or a
+  /// DIEUnit which contains this DIE as its unit DIE.
+  PointerUnion<DIE *, DIEUnit *> Owner;
+
+  explicit DIE(dwarf::Tag Tag) : Tag(Tag) {}
+
+public:
+  DIE() = delete;
+  DIE(const DIE &RHS) = delete;
+  DIE(DIE &&RHS) = delete;
+  DIE &operator=(const DIE &RHS) = delete;
+  DIE &operator=(const DIE &&RHS) = delete;
+
+  static DIE *get(BumpPtrAllocator &Alloc, dwarf::Tag Tag) {
+    return new (Alloc) DIE(Tag);
+  }
+
+  // Accessors.
+  unsigned getAbbrevNumber() const { return AbbrevNumber; }
+  dwarf::Tag getTag() const { return Tag; }
+  /// Get the compile/type unit relative offset of this DIE.
+  unsigned getOffset() const { return Offset; }
+  unsigned getSize() const { return Size; }
+  bool hasChildren() const { return ForceChildren || !Children.empty(); }
+  void setForceChildren(bool B) { ForceChildren = B; }
+
+  using child_iterator = IntrusiveBackList<DIE>::iterator;
+  using const_child_iterator = IntrusiveBackList<DIE>::const_iterator;
+  using child_range = iterator_range<child_iterator>;
+  using const_child_range = iterator_range<const_child_iterator>;
+
+  child_range children() {
+    return make_range(Children.begin(), Children.end());
+  }
+  const_child_range children() const {
+    return make_range(Children.begin(), Children.end());
+  }
+
+  DIE *getParent() const;
+
+  /// Generate the abbreviation for this DIE.
+  ///
+  /// Calculate the abbreviation for this, which should be uniqued and
+  /// eventually used to call \a setAbbrevNumber().
+  DIEAbbrev generateAbbrev() const;
+
+  /// Set the abbreviation number for this DIE.
+  void setAbbrevNumber(unsigned I) { AbbrevNumber = I; }
+
+  /// Get the absolute offset within the .debug_info or .debug_types section
+  /// for this DIE.
+  unsigned getDebugSectionOffset() const;
+
+  /// Compute the offset of this DIE and all its children.
+  ///
+  /// This function gets called just before we are going to generate the debug
+  /// information and gives each DIE a chance to figure out its CU relative DIE
+  /// offset, unique its abbreviation and fill in the abbreviation code, and
+  /// return the unit offset that points to where the next DIE will be emitted
+  /// within the debug unit section. After this function has been called for all
+  /// DIE objects, the DWARF can be generated since all DIEs will be able to
+  /// properly refer to other DIE objects since all DIEs have calculated their
+  /// offsets.
+  ///
+  /// \param AP AsmPrinter to use when calculating sizes.
+  /// \param AbbrevSet the abbreviation used to unique DIE abbreviations.
+  /// \param CUOffset the compile/type unit relative offset in bytes.
+  /// \returns the offset for the DIE that follows this DIE within the
+  /// current compile/type unit.
+  unsigned computeOffsetsAndAbbrevs(const AsmPrinter *AP,
+                                    DIEAbbrevSet &AbbrevSet, unsigned CUOffset);
+
+  /// Climb up the parent chain to get the compile unit or type unit DIE that
+  /// this DIE belongs to.
+  ///
+  /// \returns the compile or type unit DIE that owns this DIE, or NULL if
+  /// this DIE hasn't been added to a unit DIE.
+  const DIE *getUnitDie() const;
+
+  /// Climb up the parent chain to get the compile unit or type unit that this
+  /// DIE belongs to.
+  ///
+  /// \returns the DIEUnit that represents the compile or type unit that owns
+  /// this DIE, or NULL if this DIE hasn't been added to a unit DIE.
+  const DIEUnit *getUnit() const;
+
+  void setOffset(unsigned O) { Offset = O; }
+  void setSize(unsigned S) { Size = S; }
+
+  /// Add a child to the DIE.
+  DIE &addChild(DIE *Child) {
+    assert(!Child->getParent() && "Child should be orphaned");
+    Child->Owner = this;
+    Children.push_back(*Child);
+    return Children.back();
+  }
+
+  /// Find a value in the DIE with the attribute given.
+  ///
+  /// Returns a default-constructed DIEValue (where \a DIEValue::getType()
+  /// gives \a DIEValue::isNone) if no such attribute exists.
+  DIEValue findAttribute(dwarf::Attribute Attribute) const;
+
+  void print(raw_ostream &O, unsigned IndentCount = 0) const;
+  void dump() const;
+};
+
+//===--------------------------------------------------------------------===//
+/// Represents a compile or type unit.
+class DIEUnit {
+  /// The compile unit or type unit DIE. This variable must be an instance of
+  /// DIE so that we can calculate the DIEUnit from any DIE by traversing the
+  /// parent backchain and getting the Unit DIE, and then casting itself to a
+  /// DIEUnit. This allows us to be able to find the DIEUnit for any DIE without
+  /// having to store a pointer to the DIEUnit in each DIE instance.
+  DIE Die;
+  /// The section this unit will be emitted in. This may or may not be set to
+  /// a valid section depending on the client that is emitting DWARF.
+  MCSection *Section;
+  uint64_t Offset; /// .debug_info or .debug_types absolute section offset.
+  uint32_t Length; /// The length in bytes of all of the DIEs in this unit.
+  const uint16_t Version; /// The Dwarf version number for this unit.
+  const uint8_t AddrSize; /// The size in bytes of an address for this unit.
+protected:
+  ~DIEUnit() = default;
+
+public:
+  DIEUnit(uint16_t Version, uint8_t AddrSize, dwarf::Tag UnitTag);
+  DIEUnit(const DIEUnit &RHS) = delete;
+  DIEUnit(DIEUnit &&RHS) = delete;
+  void operator=(const DIEUnit &RHS) = delete;
+  void operator=(const DIEUnit &&RHS) = delete;
+  /// Set the section that this DIEUnit will be emitted into.
+  ///
+  /// This function is used by some clients to set the section. Not all clients
+  /// that emit DWARF use this section variable.
+  void setSection(MCSection *Section) {
+    assert(!this->Section);
+    this->Section = Section;
+  }
+
+  virtual const MCSymbol *getCrossSectionRelativeBaseAddress() const {
+    return nullptr;
+  }
+
+  /// Return the section that this DIEUnit will be emitted into.
+  ///
+  /// \returns Section pointer which can be NULL.
+  MCSection *getSection() const { return Section; }
+  void setDebugSectionOffset(unsigned O) { Offset = O; }
+  unsigned getDebugSectionOffset() const { return Offset; }
+  void setLength(uint64_t L) { Length = L; }
+  uint64_t getLength() const { return Length; }
+  uint16_t getDwarfVersion() const { return Version; }
+  uint16_t getAddressSize() const { return AddrSize; }
+  DIE &getUnitDie() { return Die; }
+  const DIE &getUnitDie() const { return Die; }
+};
+
+struct BasicDIEUnit final : DIEUnit {
+  BasicDIEUnit(uint16_t Version, uint8_t AddrSize, dwarf::Tag UnitTag)
+      : DIEUnit(Version, AddrSize, UnitTag) {}
+};
+
+//===--------------------------------------------------------------------===//
+/// DIELoc - Represents an expression location.
+//
+class DIELoc : public DIEValueList {
+  mutable unsigned Size = 0; // Size in bytes excluding size header.
+
+public:
+  DIELoc() = default;
+
+  /// ComputeSize - Calculate the size of the location expression.
+  ///
+  unsigned ComputeSize(const AsmPrinter *AP) const;
+
+  /// BestForm - Choose the best form for data.
+  ///
+  dwarf::Form BestForm(unsigned DwarfVersion) const {
+    if (DwarfVersion > 3)
+      return dwarf::DW_FORM_exprloc;
+    // Pre-DWARF4 location expressions were blocks and not exprloc.
+    if ((unsigned char)Size == Size)
+      return dwarf::DW_FORM_block1;
+    if ((unsigned short)Size == Size)
+      return dwarf::DW_FORM_block2;
+    if ((unsigned int)Size == Size)
+      return dwarf::DW_FORM_block4;
+    return dwarf::DW_FORM_block;
+  }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+//===--------------------------------------------------------------------===//
+/// DIEBlock - Represents a block of values.
+//
+class DIEBlock : public DIEValueList {
+  mutable unsigned Size = 0; // Size in bytes excluding size header.
+
+public:
+  DIEBlock() = default;
+
+  /// ComputeSize - Calculate the size of the location expression.
+  ///
+  unsigned ComputeSize(const AsmPrinter *AP) const;
+
+  /// BestForm - Choose the best form for data.
+  ///
+  dwarf::Form BestForm() const {
+    if ((unsigned char)Size == Size)
+      return dwarf::DW_FORM_block1;
+    if ((unsigned short)Size == Size)
+      return dwarf::DW_FORM_block2;
+    if ((unsigned int)Size == Size)
+      return dwarf::DW_FORM_block4;
+    return dwarf::DW_FORM_block;
+  }
+
+  void EmitValue(const AsmPrinter *AP, dwarf::Form Form) const;
+  unsigned SizeOf(const AsmPrinter *AP, dwarf::Form Form) const;
+
+  void print(raw_ostream &O) const;
+};
+
+} // end namespace llvm
+
+#endif // LLVM_LIB_CODEGEN_ASMPRINTER_DIE_H