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diff --git a/llvm/tools/llvm-objcopy/MachO/Object.h b/llvm/tools/llvm-objcopy/MachO/Object.h
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+++ b/llvm/tools/llvm-objcopy/MachO/Object.h
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+//===- Object.h - Mach-O object file model ----------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_OBJCOPY_MACHO_OBJECT_H
+#define LLVM_OBJCOPY_MACHO_OBJECT_H
+
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/BinaryFormat/MachO.h"
+#include "llvm/MC/StringTableBuilder.h"
+#include "llvm/ObjectYAML/DWARFYAML.h"
+#include "llvm/Support/YAMLTraits.h"
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace llvm {
+namespace objcopy {
+namespace macho {
+
+struct MachHeader {
+  uint32_t Magic;
+  uint32_t CPUType;
+  uint32_t CPUSubType;
+  uint32_t FileType;
+  uint32_t NCmds;
+  uint32_t SizeOfCmds;
+  uint32_t Flags;
+  uint32_t Reserved = 0;
+};
+
+struct RelocationInfo;
+struct Section {
+  std::string Sectname;
+  std::string Segname;
+  uint64_t Addr;
+  uint64_t Size;
+  uint32_t Offset;
+  uint32_t Align;
+  uint32_t RelOff;
+  uint32_t NReloc;
+  uint32_t Flags;
+  uint32_t Reserved1;
+  uint32_t Reserved2;
+  uint32_t Reserved3;
+
+  StringRef Content;
+  std::vector<RelocationInfo> Relocations;
+
+  MachO::SectionType getType() const {
+    return static_cast<MachO::SectionType>(Flags & MachO::SECTION_TYPE);
+  }
+
+  bool isVirtualSection() const {
+    return (getType() == MachO::S_ZEROFILL ||
+            getType() == MachO::S_GB_ZEROFILL ||
+            getType() == MachO::S_THREAD_LOCAL_ZEROFILL);
+  }
+};
+
+struct LoadCommand {
+  // The type MachO::macho_load_command is defined in llvm/BinaryFormat/MachO.h
+  // and it is a union of all the structs corresponding to various load
+  // commands.
+  MachO::macho_load_command MachOLoadCommand;
+
+  // The raw content of the payload of the load command (located right after the
+  // corresponding struct). In some cases it is either empty or can be
+  // copied-over without digging into its structure.
+  ArrayRef<uint8_t> Payload;
+
+  // Some load commands can contain (inside the payload) an array of sections,
+  // though the contents of the sections are stored separately. The struct
+  // Section describes only sections' metadata and where to find the
+  // corresponding content inside the binary.
+  std::vector<Section> Sections;
+};
+
+// A symbol information. Fields which starts with "n_" are same as them in the
+// nlist.
+struct SymbolEntry {
+  std::string Name;
+  uint32_t Index;
+  uint8_t n_type;
+  uint8_t n_sect;
+  uint16_t n_desc;
+  uint64_t n_value;
+
+  bool isExternalSymbol() const {
+    return n_type & ((MachO::N_EXT | MachO::N_PEXT));
+  }
+
+  bool isLocalSymbol() const { return !isExternalSymbol(); }
+
+  bool isUndefinedSymbol() const {
+    return (n_type & MachO::N_TYPE) == MachO::N_UNDF;
+  }
+};
+
+/// The location of the symbol table inside the binary is described by LC_SYMTAB
+/// load command.
+struct SymbolTable {
+  std::vector<std::unique_ptr<SymbolEntry>> Symbols;
+
+  const SymbolEntry *getSymbolByIndex(uint32_t Index) const;
+};
+
+struct IndirectSymbolTable {
+  std::vector<uint32_t> Symbols;
+};
+
+/// The location of the string table inside the binary is described by LC_SYMTAB
+/// load command.
+struct StringTable {
+  std::vector<std::string> Strings;
+};
+
+struct RelocationInfo {
+  const SymbolEntry *Symbol;
+  // True if Info is a scattered_relocation_info.
+  bool Scattered;
+  MachO::any_relocation_info Info;
+};
+
+/// The location of the rebase info inside the binary is described by
+/// LC_DYLD_INFO load command. Dyld rebases an image whenever dyld loads it at
+/// an address different from its preferred address.  The rebase information is
+/// a stream of byte sized opcodes whose symbolic names start with
+/// REBASE_OPCODE_. Conceptually the rebase information is a table of tuples:
+///   <seg-index, seg-offset, type>
+/// The opcodes are a compressed way to encode the table by only
+/// encoding when a column changes.  In addition simple patterns
+/// like "every n'th offset for m times" can be encoded in a few
+/// bytes.
+struct RebaseInfo {
+  // At the moment we do not parse this info (and it is simply copied over),
+  // but the proper support will be added later.
+  ArrayRef<uint8_t> Opcodes;
+};
+
+/// The location of the bind info inside the binary is described by
+/// LC_DYLD_INFO load command. Dyld binds an image during the loading process,
+/// if the image requires any pointers to be initialized to symbols in other
+/// images. The bind information is a stream of byte sized opcodes whose
+/// symbolic names start with BIND_OPCODE_. Conceptually the bind information is
+/// a table of tuples: <seg-index, seg-offset, type, symbol-library-ordinal,
+/// symbol-name, addend> The opcodes are a compressed way to encode the table by
+/// only encoding when a column changes.  In addition simple patterns like for
+/// runs of pointers initialized to the same value can be encoded in a few
+/// bytes.
+struct BindInfo {
+  // At the moment we do not parse this info (and it is simply copied over),
+  // but the proper support will be added later.
+  ArrayRef<uint8_t> Opcodes;
+};
+
+/// The location of the weak bind info inside the binary is described by
+/// LC_DYLD_INFO load command. Some C++ programs require dyld to unique symbols
+/// so that all images in the process use the same copy of some code/data. This
+/// step is done after binding. The content of the weak_bind info is an opcode
+/// stream like the bind_info.  But it is sorted alphabetically by symbol name.
+/// This enable dyld to walk all images with weak binding information in order
+/// and look for collisions.  If there are no collisions, dyld does no updating.
+/// That means that some fixups are also encoded in the bind_info.  For
+/// instance, all calls to "operator new" are first bound to libstdc++.dylib
+/// using the information in bind_info.  Then if some image overrides operator
+/// new that is detected when the weak_bind information is processed and the
+/// call to operator new is then rebound.
+struct WeakBindInfo {
+  // At the moment we do not parse this info (and it is simply copied over),
+  // but the proper support will be added later.
+  ArrayRef<uint8_t> Opcodes;
+};
+
+/// The location of the lazy bind info inside the binary is described by
+/// LC_DYLD_INFO load command. Some uses of external symbols do not need to be
+/// bound immediately. Instead they can be lazily bound on first use.  The
+/// lazy_bind contains a stream of BIND opcodes to bind all lazy symbols. Normal
+/// use is that dyld ignores the lazy_bind section when loading an image.
+/// Instead the static linker arranged for the lazy pointer to initially point
+/// to a helper function which pushes the offset into the lazy_bind area for the
+/// symbol needing to be bound, then jumps to dyld which simply adds the offset
+/// to lazy_bind_off to get the information on what to bind.
+struct LazyBindInfo {
+  ArrayRef<uint8_t> Opcodes;
+};
+
+/// The location of the export info inside the binary is described by
+/// LC_DYLD_INFO load command. The symbols exported by a dylib are encoded in a
+/// trie.  This is a compact representation that factors out common prefixes. It
+/// also reduces LINKEDIT pages in RAM because it encodes all information (name,
+/// address, flags) in one small, contiguous range. The export area is a stream
+/// of nodes.  The first node sequentially is the start node for the trie. Nodes
+/// for a symbol start with a uleb128 that is the length of the exported symbol
+/// information for the string so far. If there is no exported symbol, the node
+/// starts with a zero byte. If there is exported info, it follows the length.
+/// First is a uleb128 containing flags. Normally, it is followed by
+/// a uleb128 encoded offset which is location of the content named
+/// by the symbol from the mach_header for the image.  If the flags
+/// is EXPORT_SYMBOL_FLAGS_REEXPORT, then following the flags is
+/// a uleb128 encoded library ordinal, then a zero terminated
+/// UTF8 string.  If the string is zero length, then the symbol
+/// is re-export from the specified dylib with the same name.
+/// If the flags is EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER, then following
+/// the flags is two uleb128s: the stub offset and the resolver offset.
+/// The stub is used by non-lazy pointers.  The resolver is used
+/// by lazy pointers and must be called to get the actual address to use.
+/// After the optional exported symbol information is a byte of
+/// how many edges (0-255) that this node has leaving it,
+/// followed by each edge.
+/// Each edge is a zero terminated UTF8 of the addition chars
+/// in the symbol, followed by a uleb128 offset for the node that
+/// edge points to.
+struct ExportInfo {
+  ArrayRef<uint8_t> Trie;
+};
+
+struct LinkData {
+  ArrayRef<uint8_t> Data;
+};
+
+struct Object {
+  MachHeader Header;
+  std::vector<LoadCommand> LoadCommands;
+
+  SymbolTable SymTable;
+  StringTable StrTable;
+
+  RebaseInfo Rebases;
+  BindInfo Binds;
+  WeakBindInfo WeakBinds;
+  LazyBindInfo LazyBinds;
+  ExportInfo Exports;
+  IndirectSymbolTable IndirectSymTable;
+  LinkData DataInCode;
+  LinkData FunctionStarts;
+
+  /// The index of LC_SYMTAB load command if present.
+  Optional<size_t> SymTabCommandIndex;
+  /// The index of LC_DYLD_INFO or LC_DYLD_INFO_ONLY load command if present.
+  Optional<size_t> DyLdInfoCommandIndex;
+  /// The index LC_DYSYMTAB load comamnd if present.
+  Optional<size_t> DySymTabCommandIndex;
+  /// The index LC_DATA_IN_CODE load comamnd if present.
+  Optional<size_t> DataInCodeCommandIndex;
+  /// The index LC_FUNCTION_STARTS load comamnd if present.
+  Optional<size_t> FunctionStartsCommandIndex;
+};
+
+} // end namespace macho
+} // end namespace objcopy
+} // end namespace llvm
+
+#endif // LLVM_OBJCOPY_MACHO_OBJECT_H