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diff --git a/third_party/llvm-project/include/llvm/MC/MCSymbol.h b/third_party/llvm-project/include/llvm/MC/MCSymbol.h
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+++ b/third_party/llvm-project/include/llvm/MC/MCSymbol.h
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+//===- MCSymbol.h - Machine Code Symbols ------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declaration of the MCSymbol class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCSYMBOL_H
+#define LLVM_MC_MCSYMBOL_H
+
+#include "llvm/ADT/PointerIntPair.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/MC/MCFragment.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MathExtras.h"
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+
+namespace llvm {
+
+class MCAsmInfo;
+class MCContext;
+class MCExpr;
+class MCSection;
+class raw_ostream;
+
+/// MCSymbol - Instances of this class represent a symbol name in the MC file,
+/// and MCSymbols are created and uniqued by the MCContext class.  MCSymbols
+/// should only be constructed with valid names for the object file.
+///
+/// If the symbol is defined/emitted into the current translation unit, the
+/// Section member is set to indicate what section it lives in.  Otherwise, if
+/// it is a reference to an external entity, it has a null section.
+class MCSymbol {
+protected:
+  /// The kind of the symbol.  If it is any value other than unset then this
+  /// class is actually one of the appropriate subclasses of MCSymbol.
+  enum SymbolKind {
+    SymbolKindUnset,
+    SymbolKindCOFF,
+    SymbolKindELF,
+    SymbolKindMachO,
+    SymbolKindWasm,
+    SymbolKindXCOFF,
+  };
+
+  /// A symbol can contain an Offset, or Value, or be Common, but never more
+  /// than one of these.
+  enum Contents : uint8_t {
+    SymContentsUnset,
+    SymContentsOffset,
+    SymContentsVariable,
+    SymContentsCommon,
+    SymContentsTargetCommon, // Index stores the section index
+  };
+
+  // Special sentinal value for the absolute pseudo fragment.
+  static MCFragment *AbsolutePseudoFragment;
+
+  /// If a symbol has a Fragment, the section is implied, so we only need
+  /// one pointer.
+  /// The special AbsolutePseudoFragment value is for absolute symbols.
+  /// If this is a variable symbol, this caches the variable value's fragment.
+  /// FIXME: We might be able to simplify this by having the asm streamer create
+  /// dummy fragments.
+  /// If this is a section, then it gives the symbol is defined in. This is null
+  /// for undefined symbols.
+  ///
+  /// If this is a fragment, then it gives the fragment this symbol's value is
+  /// relative to, if any.
+  ///
+  /// For the 'HasName' integer, this is true if this symbol is named.
+  /// A named symbol will have a pointer to the name allocated in the bytes
+  /// immediately prior to the MCSymbol.
+  mutable PointerIntPair<MCFragment *, 1> FragmentAndHasName;
+
+  /// IsTemporary - True if this is an assembler temporary label, which
+  /// typically does not survive in the .o file's symbol table.  Usually
+  /// "Lfoo" or ".foo".
+  unsigned IsTemporary : 1;
+
+  /// True if this symbol can be redefined.
+  unsigned IsRedefinable : 1;
+
+  /// IsUsed - True if this symbol has been used.
+  mutable unsigned IsUsed : 1;
+
+  mutable unsigned IsRegistered : 1;
+
+  /// This symbol is visible outside this translation unit.
+  mutable unsigned IsExternal : 1;
+
+  /// This symbol is private extern.
+  mutable unsigned IsPrivateExtern : 1;
+
+  /// LLVM RTTI discriminator. This is actually a SymbolKind enumerator, but is
+  /// unsigned to avoid sign extension and achieve better bitpacking with MSVC.
+  unsigned Kind : 3;
+
+  /// True if we have created a relocation that uses this symbol.
+  mutable unsigned IsUsedInReloc : 1;
+
+  /// This is actually a Contents enumerator, but is unsigned to avoid sign
+  /// extension and achieve better bitpacking with MSVC.
+  unsigned SymbolContents : 3;
+
+  /// The alignment of the symbol, if it is 'common', or -1.
+  ///
+  /// The alignment is stored as log2(align) + 1.  This allows all values from
+  /// 0 to 2^31 to be stored which is every power of 2 representable by an
+  /// unsigned.
+  enum : unsigned { NumCommonAlignmentBits = 5 };
+  unsigned CommonAlignLog2 : NumCommonAlignmentBits;
+
+  /// The Flags field is used by object file implementations to store
+  /// additional per symbol information which is not easily classified.
+  enum : unsigned { NumFlagsBits = 16 };
+  mutable uint32_t Flags : NumFlagsBits;
+
+  /// Index field, for use by the object file implementation.
+  mutable uint32_t Index = 0;
+
+  union {
+    /// The offset to apply to the fragment address to form this symbol's value.
+    uint64_t Offset;
+
+    /// The size of the symbol, if it is 'common'.
+    uint64_t CommonSize;
+
+    /// If non-null, the value for a variable symbol.
+    const MCExpr *Value;
+  };
+
+  // MCContext creates and uniques these.
+  friend class MCExpr;
+  friend class MCContext;
+
+  /// The name for a symbol.
+  /// MCSymbol contains a uint64_t so is probably aligned to 8.  On a 32-bit
+  /// system, the name is a pointer so isn't going to satisfy the 8 byte
+  /// alignment of uint64_t.  Account for that here.
+  using NameEntryStorageTy = union {
+    const StringMapEntry<bool> *NameEntry;
+    uint64_t AlignmentPadding;
+  };
+
+  MCSymbol(SymbolKind Kind, const StringMapEntry<bool> *Name, bool isTemporary)
+      : IsTemporary(isTemporary), IsRedefinable(false), IsUsed(false),
+        IsRegistered(false), IsExternal(false), IsPrivateExtern(false),
+        Kind(Kind), IsUsedInReloc(false), SymbolContents(SymContentsUnset),
+        CommonAlignLog2(0), Flags(0) {
+    Offset = 0;
+    FragmentAndHasName.setInt(!!Name);
+    if (Name)
+      getNameEntryPtr() = Name;
+  }
+
+  // Provide custom new/delete as we will only allocate space for a name
+  // if we need one.
+  void *operator new(size_t s, const StringMapEntry<bool> *Name,
+                     MCContext &Ctx);
+
+private:
+  void operator delete(void *);
+  /// Placement delete - required by std, but never called.
+  void operator delete(void*, unsigned) {
+    llvm_unreachable("Constructor throws?");
+  }
+  /// Placement delete - required by std, but never called.
+  void operator delete(void*, unsigned, bool) {
+    llvm_unreachable("Constructor throws?");
+  }
+
+  MCSection *getSectionPtr() const {
+    if (MCFragment *F = getFragment()) {
+      assert(F != AbsolutePseudoFragment);
+      return F->getParent();
+    }
+    return nullptr;
+  }
+
+  /// Get a reference to the name field.  Requires that we have a name
+  const StringMapEntry<bool> *&getNameEntryPtr() {
+    assert(FragmentAndHasName.getInt() && "Name is required");
+    NameEntryStorageTy *Name = reinterpret_cast<NameEntryStorageTy *>(this);
+    return (*(Name - 1)).NameEntry;
+  }
+  const StringMapEntry<bool> *&getNameEntryPtr() const {
+    return const_cast<MCSymbol*>(this)->getNameEntryPtr();
+  }
+
+public:
+  MCSymbol(const MCSymbol &) = delete;
+  MCSymbol &operator=(const MCSymbol &) = delete;
+
+  /// getName - Get the symbol name.
+  StringRef getName() const {
+    if (!FragmentAndHasName.getInt())
+      return StringRef();
+
+    return getNameEntryPtr()->first();
+  }
+
+  bool isRegistered() const { return IsRegistered; }
+  void setIsRegistered(bool Value) const { IsRegistered = Value; }
+
+  void setUsedInReloc() const { IsUsedInReloc = true; }
+  bool isUsedInReloc() const { return IsUsedInReloc; }
+
+  /// \name Accessors
+  /// @{
+
+  /// isTemporary - Check if this is an assembler temporary symbol.
+  bool isTemporary() const { return IsTemporary; }
+
+  /// isUsed - Check if this is used.
+  bool isUsed() const { return IsUsed; }
+
+  /// Check if this symbol is redefinable.
+  bool isRedefinable() const { return IsRedefinable; }
+  /// Mark this symbol as redefinable.
+  void setRedefinable(bool Value) { IsRedefinable = Value; }
+  /// Prepare this symbol to be redefined.
+  void redefineIfPossible() {
+    if (IsRedefinable) {
+      if (SymbolContents == SymContentsVariable) {
+        Value = nullptr;
+        SymbolContents = SymContentsUnset;
+      }
+      setUndefined();
+      IsRedefinable = false;
+    }
+  }
+
+  /// @}
+  /// \name Associated Sections
+  /// @{
+
+  /// isDefined - Check if this symbol is defined (i.e., it has an address).
+  ///
+  /// Defined symbols are either absolute or in some section.
+  bool isDefined() const { return !isUndefined(); }
+
+  /// isInSection - Check if this symbol is defined in some section (i.e., it
+  /// is defined but not absolute).
+  bool isInSection() const {
+    return isDefined() && !isAbsolute();
+  }
+
+  /// isUndefined - Check if this symbol undefined (i.e., implicitly defined).
+  bool isUndefined(bool SetUsed = true) const {
+    return getFragment(SetUsed) == nullptr;
+  }
+
+  /// isAbsolute - Check if this is an absolute symbol.
+  bool isAbsolute() const {
+    return getFragment() == AbsolutePseudoFragment;
+  }
+
+  /// Get the section associated with a defined, non-absolute symbol.
+  MCSection &getSection() const {
+    assert(isInSection() && "Invalid accessor!");
+    return *getSectionPtr();
+  }
+
+  /// Mark the symbol as defined in the fragment \p F.
+  void setFragment(MCFragment *F) const {
+    assert(!isVariable() && "Cannot set fragment of variable");
+    FragmentAndHasName.setPointer(F);
+  }
+
+  /// Mark the symbol as undefined.
+  void setUndefined() { FragmentAndHasName.setPointer(nullptr); }
+
+  bool isELF() const { return Kind == SymbolKindELF; }
+
+  bool isCOFF() const { return Kind == SymbolKindCOFF; }
+
+  bool isMachO() const { return Kind == SymbolKindMachO; }
+
+  bool isWasm() const { return Kind == SymbolKindWasm; }
+
+  bool isXCOFF() const { return Kind == SymbolKindXCOFF; }
+
+  /// @}
+  /// \name Variable Symbols
+  /// @{
+
+  /// isVariable - Check if this is a variable symbol.
+  bool isVariable() const {
+    return SymbolContents == SymContentsVariable;
+  }
+
+  /// getVariableValue - Get the value for variable symbols.
+  const MCExpr *getVariableValue(bool SetUsed = true) const {
+    assert(isVariable() && "Invalid accessor!");
+    IsUsed |= SetUsed;
+    return Value;
+  }
+
+  void setVariableValue(const MCExpr *Value);
+
+  /// @}
+
+  /// Get the (implementation defined) index.
+  uint32_t getIndex() const {
+    return Index;
+  }
+
+  /// Set the (implementation defined) index.
+  void setIndex(uint32_t Value) const {
+    Index = Value;
+  }
+
+  bool isUnset() const { return SymbolContents == SymContentsUnset; }
+
+  uint64_t getOffset() const {
+    assert((SymbolContents == SymContentsUnset ||
+            SymbolContents == SymContentsOffset) &&
+           "Cannot get offset for a common/variable symbol");
+    return Offset;
+  }
+  void setOffset(uint64_t Value) {
+    assert((SymbolContents == SymContentsUnset ||
+            SymbolContents == SymContentsOffset) &&
+           "Cannot set offset for a common/variable symbol");
+    Offset = Value;
+    SymbolContents = SymContentsOffset;
+  }
+
+  /// Return the size of a 'common' symbol.
+  uint64_t getCommonSize() const {
+    assert(isCommon() && "Not a 'common' symbol!");
+    return CommonSize;
+  }
+
+  /// Mark this symbol as being 'common'.
+  ///
+  /// \param Size - The size of the symbol.
+  /// \param Align - The alignment of the symbol.
+  /// \param Target - Is the symbol a target-specific common-like symbol.
+  void setCommon(uint64_t Size, unsigned Align, bool Target = false) {
+    assert(getOffset() == 0);
+    CommonSize = Size;
+    SymbolContents = Target ? SymContentsTargetCommon : SymContentsCommon;
+
+    assert((!Align || isPowerOf2_32(Align)) &&
+           "Alignment must be a power of 2");
+    unsigned Log2Align = Log2_32(Align) + 1;
+    assert(Log2Align < (1U << NumCommonAlignmentBits) &&
+           "Out of range alignment");
+    CommonAlignLog2 = Log2Align;
+  }
+
+  ///  Return the alignment of a 'common' symbol.
+  unsigned getCommonAlignment() const {
+    assert(isCommon() && "Not a 'common' symbol!");
+    return CommonAlignLog2 ? (1U << (CommonAlignLog2 - 1)) : 0;
+  }
+
+  /// Declare this symbol as being 'common'.
+  ///
+  /// \param Size - The size of the symbol.
+  /// \param Align - The alignment of the symbol.
+  /// \param Target - Is the symbol a target-specific common-like symbol.
+  /// \return True if symbol was already declared as a different type
+  bool declareCommon(uint64_t Size, unsigned Align, bool Target = false) {
+    assert(isCommon() || getOffset() == 0);
+    if(isCommon()) {
+      if (CommonSize != Size || getCommonAlignment() != Align ||
+          isTargetCommon() != Target)
+        return true;
+    } else
+      setCommon(Size, Align, Target);
+    return false;
+  }
+
+  /// Is this a 'common' symbol.
+  bool isCommon() const {
+    return SymbolContents == SymContentsCommon ||
+           SymbolContents == SymContentsTargetCommon;
+  }
+
+  /// Is this a target-specific common-like symbol.
+  bool isTargetCommon() const {
+    return SymbolContents == SymContentsTargetCommon;
+  }
+
+  MCFragment *getFragment(bool SetUsed = true) const {
+    MCFragment *Fragment = FragmentAndHasName.getPointer();
+    if (Fragment || !isVariable())
+      return Fragment;
+    Fragment = getVariableValue(SetUsed)->findAssociatedFragment();
+    FragmentAndHasName.setPointer(Fragment);
+    return Fragment;
+  }
+
+  bool isExternal() const { return IsExternal; }
+  void setExternal(bool Value) const { IsExternal = Value; }
+
+  bool isPrivateExtern() const { return IsPrivateExtern; }
+  void setPrivateExtern(bool Value) { IsPrivateExtern = Value; }
+
+  /// print - Print the value to the stream \p OS.
+  void print(raw_ostream &OS, const MCAsmInfo *MAI) const;
+
+  /// dump - Print the value to stderr.
+  void dump() const;
+
+protected:
+  /// Get the (implementation defined) symbol flags.
+  uint32_t getFlags() const { return Flags; }
+
+  /// Set the (implementation defined) symbol flags.
+  void setFlags(uint32_t Value) const {
+    assert(Value < (1U << NumFlagsBits) && "Out of range flags");
+    Flags = Value;
+  }
+
+  /// Modify the flags via a mask
+  void modifyFlags(uint32_t Value, uint32_t Mask) const {
+    assert(Value < (1U << NumFlagsBits) && "Out of range flags");
+    Flags = (Flags & ~Mask) | Value;
+  }
+};
+
+inline raw_ostream &operator<<(raw_ostream &OS, const MCSymbol &Sym) {
+  Sym.print(OS, nullptr);
+  return OS;
+}
+
+} // end namespace llvm
+
+#endif // LLVM_MC_MCSYMBOL_H