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1//===- yaml2coff - Convert YAML to a COFF object file ---------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8///9/// \file10/// The COFF component of yaml2obj.11///12//===----------------------------------------------------------------------===//13 14#include "llvm/ADT/StringExtras.h"15#include "llvm/ADT/StringMap.h"16#include "llvm/DebugInfo/CodeView/StringsAndChecksums.h"17#include "llvm/ObjectYAML/ObjectYAML.h"18#include "llvm/ObjectYAML/yaml2obj.h"19#include "llvm/Support/BinaryStreamWriter.h"20#include "llvm/Support/Endian.h"21#include "llvm/Support/SourceMgr.h"22#include "llvm/Support/WithColor.h"23#include "llvm/Support/raw_ostream.h"24#include <optional>25#include <vector>26 27using namespace llvm;28 29namespace {30 31/// This parses a yaml stream that represents a COFF object file.32/// See docs/yaml2obj for the yaml scheema.33struct COFFParser {34  COFFParser(COFFYAML::Object &Obj, yaml::ErrorHandler EH)35      : Obj(Obj), SectionTableStart(0), SectionTableSize(0), ErrHandler(EH) {36    // A COFF string table always starts with a 4 byte size field. Offsets into37    // it include this size, so allocate it now.38    StringTable.append(4, char(0));39  }40 41  bool useBigObj() const {42    return static_cast<int32_t>(Obj.Sections.size()) >43           COFF::MaxNumberOfSections16;44  }45 46  bool isPE() const { return Obj.OptionalHeader.has_value(); }47  bool is64Bit() const { return COFF::is64Bit(Obj.Header.Machine); }48 49  uint32_t getFileAlignment() const {50    return Obj.OptionalHeader->Header.FileAlignment;51  }52 53  unsigned getHeaderSize() const {54    return useBigObj() ? COFF::Header32Size : COFF::Header16Size;55  }56 57  unsigned getSymbolSize() const {58    return useBigObj() ? COFF::Symbol32Size : COFF::Symbol16Size;59  }60 61  bool parseSections() {62    for (COFFYAML::Section &Sec : Obj.Sections) {63      // If the name is less than 8 bytes, store it in place, otherwise64      // store it in the string table.65      StringRef Name = Sec.Name;66 67      if (Name.size() <= COFF::NameSize) {68        llvm::copy(Name, Sec.Header.Name);69      } else {70        // Add string to the string table and format the index for output.71        unsigned Index = getStringIndex(Name);72        std::string str = utostr(Index);73        if (str.size() > 7) {74          ErrHandler("string table got too large");75          return false;76        }77        Sec.Header.Name[0] = '/';78        llvm::copy(str, Sec.Header.Name + 1);79      }80 81      if (Sec.Alignment) {82        if (Sec.Alignment > 8192) {83          ErrHandler("section alignment is too large");84          return false;85        }86        if (!isPowerOf2_32(Sec.Alignment)) {87          ErrHandler("section alignment is not a power of 2");88          return false;89        }90        Sec.Header.Characteristics |= (Log2_32(Sec.Alignment) + 1) << 20;91      }92    }93    return true;94  }95 96  bool parseSymbols() {97    for (COFFYAML::Symbol &Sym : Obj.Symbols) {98      // If the name is less than 8 bytes, store it in place, otherwise99      // store it in the string table.100      StringRef Name = Sym.Name;101      if (Name.size() <= COFF::NameSize) {102        llvm::copy(Name, Sym.Header.Name);103      } else {104        // Add string to the string table and format the index for output.105        unsigned Index = getStringIndex(Name);106        *reinterpret_cast<support::aligned_ulittle32_t *>(Sym.Header.Name + 4) =107            Index;108      }109 110      Sym.Header.Type = Sym.SimpleType;111      Sym.Header.Type |= Sym.ComplexType << COFF::SCT_COMPLEX_TYPE_SHIFT;112    }113    return true;114  }115 116  bool parse() {117    if (!parseSections())118      return false;119    if (!parseSymbols())120      return false;121    return true;122  }123 124  unsigned getStringIndex(StringRef Str) {125    auto [It, Inserted] = StringTableMap.try_emplace(Str, StringTable.size());126    if (Inserted) {127      StringTable.append(Str.begin(), Str.end());128      StringTable.push_back(0);129    }130    return It->second;131  }132 133  COFFYAML::Object &Obj;134 135  codeview::StringsAndChecksums StringsAndChecksums;136  BumpPtrAllocator Allocator;137  StringMap<unsigned> StringTableMap;138  std::string StringTable;139  uint32_t SectionTableStart;140  uint32_t SectionTableSize;141 142  yaml::ErrorHandler ErrHandler;143};144 145enum { DOSStubSize = 128 };146 147} // end anonymous namespace148 149// Take a CP and assign addresses and sizes to everything. Returns false if the150// layout is not valid to do.151static bool layoutOptionalHeader(COFFParser &CP) {152  if (!CP.isPE())153    return true;154  unsigned PEHeaderSize = CP.is64Bit() ? sizeof(object::pe32plus_header)155                                       : sizeof(object::pe32_header);156  CP.Obj.Header.SizeOfOptionalHeader =157      PEHeaderSize + sizeof(object::data_directory) *158                         CP.Obj.OptionalHeader->Header.NumberOfRvaAndSize;159  return true;160}161 162static yaml::BinaryRef163toDebugS(ArrayRef<CodeViewYAML::YAMLDebugSubsection> Subsections,164         const codeview::StringsAndChecksums &SC, BumpPtrAllocator &Allocator) {165  using namespace codeview;166  ExitOnError Err("Error occurred writing .debug$S section");167  auto CVSS =168      Err(CodeViewYAML::toCodeViewSubsectionList(Allocator, Subsections, SC));169 170  std::vector<DebugSubsectionRecordBuilder> Builders;171  uint32_t Size = sizeof(uint32_t);172  for (auto &SS : CVSS) {173    DebugSubsectionRecordBuilder B(SS);174    Size += B.calculateSerializedLength();175    Builders.push_back(std::move(B));176  }177  uint8_t *Buffer = Allocator.Allocate<uint8_t>(Size);178  MutableArrayRef<uint8_t> Output(Buffer, Size);179  BinaryStreamWriter Writer(Output, llvm::endianness::little);180 181  Err(Writer.writeInteger<uint32_t>(COFF::DEBUG_SECTION_MAGIC));182  for (const auto &B : Builders) {183    Err(B.commit(Writer, CodeViewContainer::ObjectFile));184  }185  return {Output};186}187 188// Take a CP and assign addresses and sizes to everything. Returns false if the189// layout is not valid to do.190static bool layoutCOFF(COFFParser &CP) {191  // The section table starts immediately after the header, including the192  // optional header.193  CP.SectionTableStart =194      CP.getHeaderSize() + CP.Obj.Header.SizeOfOptionalHeader;195  if (CP.isPE())196    CP.SectionTableStart += DOSStubSize + sizeof(COFF::PEMagic);197  CP.SectionTableSize = COFF::SectionSize * CP.Obj.Sections.size();198 199  uint32_t CurrentSectionDataOffset =200      CP.SectionTableStart + CP.SectionTableSize;201 202  for (COFFYAML::Section &S : CP.Obj.Sections) {203    // We support specifying exactly one of SectionData or Subsections.  So if204    // there is already some SectionData, then we don't need to do any of this.205    if (S.Name == ".debug$S" && S.SectionData.binary_size() == 0) {206      CodeViewYAML::initializeStringsAndChecksums(S.DebugS,207                                                  CP.StringsAndChecksums);208      if (CP.StringsAndChecksums.hasChecksums() &&209          CP.StringsAndChecksums.hasStrings())210        break;211    }212  }213 214  // Assign each section data address consecutively.215  for (COFFYAML::Section &S : CP.Obj.Sections) {216    if (S.Name == ".debug$S") {217      if (S.SectionData.binary_size() == 0) {218        assert(CP.StringsAndChecksums.hasStrings() &&219               "Object file does not have debug string table!");220 221        S.SectionData =222            toDebugS(S.DebugS, CP.StringsAndChecksums, CP.Allocator);223      }224    } else if (S.Name == ".debug$T") {225      if (S.SectionData.binary_size() == 0)226        S.SectionData = CodeViewYAML::toDebugT(S.DebugT, CP.Allocator, S.Name);227    } else if (S.Name == ".debug$P") {228      if (S.SectionData.binary_size() == 0)229        S.SectionData = CodeViewYAML::toDebugT(S.DebugP, CP.Allocator, S.Name);230    } else if (S.Name == ".debug$H") {231      if (S.DebugH && S.SectionData.binary_size() == 0)232        S.SectionData = CodeViewYAML::toDebugH(*S.DebugH, CP.Allocator);233    }234 235    size_t DataSize = S.SectionData.binary_size();236    for (auto E : S.StructuredData)237      DataSize += E.size();238    if (DataSize > 0) {239      CurrentSectionDataOffset = alignTo(CurrentSectionDataOffset,240                                         CP.isPE() ? CP.getFileAlignment() : 4);241      S.Header.SizeOfRawData = DataSize;242      if (CP.isPE())243        S.Header.SizeOfRawData =244            alignTo(S.Header.SizeOfRawData, CP.getFileAlignment());245      S.Header.PointerToRawData = CurrentSectionDataOffset;246      CurrentSectionDataOffset += S.Header.SizeOfRawData;247      if (!S.Relocations.empty()) {248        S.Header.PointerToRelocations = CurrentSectionDataOffset;249        if (S.Header.Characteristics & COFF::IMAGE_SCN_LNK_NRELOC_OVFL) {250          S.Header.NumberOfRelocations = 0xffff;251          CurrentSectionDataOffset += COFF::RelocationSize;252        } else253          S.Header.NumberOfRelocations = S.Relocations.size();254        CurrentSectionDataOffset += S.Relocations.size() * COFF::RelocationSize;255      }256    } else {257      // Leave SizeOfRawData unaltered. For .bss sections in object files, it258      // carries the section size.259      S.Header.PointerToRawData = 0;260    }261  }262 263  uint32_t SymbolTableStart = CurrentSectionDataOffset;264 265  // Calculate number of symbols.266  uint32_t NumberOfSymbols = 0;267  for (std::vector<COFFYAML::Symbol>::iterator i = CP.Obj.Symbols.begin(),268                                               e = CP.Obj.Symbols.end();269       i != e; ++i) {270    uint32_t NumberOfAuxSymbols = 0;271    if (i->FunctionDefinition)272      NumberOfAuxSymbols += 1;273    if (i->bfAndefSymbol)274      NumberOfAuxSymbols += 1;275    if (i->WeakExternal)276      NumberOfAuxSymbols += 1;277    if (!i->File.empty())278      NumberOfAuxSymbols +=279          (i->File.size() + CP.getSymbolSize() - 1) / CP.getSymbolSize();280    if (i->SectionDefinition)281      NumberOfAuxSymbols += 1;282    if (i->CLRToken)283      NumberOfAuxSymbols += 1;284    i->Header.NumberOfAuxSymbols = NumberOfAuxSymbols;285    NumberOfSymbols += 1 + NumberOfAuxSymbols;286  }287 288  // Store all the allocated start addresses in the header.289  CP.Obj.Header.NumberOfSections = CP.Obj.Sections.size();290  CP.Obj.Header.NumberOfSymbols = NumberOfSymbols;291  if (NumberOfSymbols > 0 || CP.StringTable.size() > 4)292    CP.Obj.Header.PointerToSymbolTable = SymbolTableStart;293  else294    CP.Obj.Header.PointerToSymbolTable = 0;295 296  *reinterpret_cast<support::ulittle32_t *>(&CP.StringTable[0]) =297      CP.StringTable.size();298 299  return true;300}301 302template <typename value_type> struct binary_le_impl {303  value_type Value;304  binary_le_impl(value_type V) : Value(V) {}305};306 307template <typename value_type>308raw_ostream &operator<<(raw_ostream &OS,309                        const binary_le_impl<value_type> &BLE) {310  char Buffer[sizeof(BLE.Value)];311  support::endian::write<value_type, llvm::endianness::little>(Buffer,312                                                               BLE.Value);313  OS.write(Buffer, sizeof(BLE.Value));314  return OS;315}316 317template <typename value_type>318binary_le_impl<value_type> binary_le(value_type V) {319  return binary_le_impl<value_type>(V);320}321 322template <size_t NumBytes> struct zeros_impl {};323 324template <size_t NumBytes>325raw_ostream &operator<<(raw_ostream &OS, const zeros_impl<NumBytes> &) {326  char Buffer[NumBytes];327  memset(Buffer, 0, sizeof(Buffer));328  OS.write(Buffer, sizeof(Buffer));329  return OS;330}331 332template <typename T> zeros_impl<sizeof(T)> zeros(const T &) {333  return zeros_impl<sizeof(T)>();334}335 336template <typename T>337static uint32_t initializeOptionalHeader(COFFParser &CP, uint16_t Magic,338                                         T Header) {339  memset(Header, 0, sizeof(*Header));340  Header->Magic = Magic;341  Header->SectionAlignment = CP.Obj.OptionalHeader->Header.SectionAlignment;342  Header->FileAlignment = CP.Obj.OptionalHeader->Header.FileAlignment;343  uint32_t SizeOfCode = 0, SizeOfInitializedData = 0,344           SizeOfUninitializedData = 0;345  uint32_t SizeOfHeaders = alignTo(CP.SectionTableStart + CP.SectionTableSize,346                                   Header->FileAlignment);347  uint32_t SizeOfImage = alignTo(SizeOfHeaders, Header->SectionAlignment);348  uint32_t BaseOfData = 0;349  for (const COFFYAML::Section &S : CP.Obj.Sections) {350    if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_CODE)351      SizeOfCode += S.Header.SizeOfRawData;352    if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)353      SizeOfInitializedData += S.Header.SizeOfRawData;354    if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)355      SizeOfUninitializedData += S.Header.SizeOfRawData;356    if (S.Name == ".text")357      Header->BaseOfCode = S.Header.VirtualAddress; // RVA358    else if (S.Name == ".data")359      BaseOfData = S.Header.VirtualAddress; // RVA360    if (S.Header.VirtualAddress)361      SizeOfImage += alignTo(S.Header.VirtualSize, Header->SectionAlignment);362  }363  Header->SizeOfCode = SizeOfCode;364  Header->SizeOfInitializedData = SizeOfInitializedData;365  Header->SizeOfUninitializedData = SizeOfUninitializedData;366  Header->AddressOfEntryPoint =367      CP.Obj.OptionalHeader->Header.AddressOfEntryPoint; // RVA368  Header->ImageBase = CP.Obj.OptionalHeader->Header.ImageBase;369  Header->MajorOperatingSystemVersion =370      CP.Obj.OptionalHeader->Header.MajorOperatingSystemVersion;371  Header->MinorOperatingSystemVersion =372      CP.Obj.OptionalHeader->Header.MinorOperatingSystemVersion;373  Header->MajorImageVersion = CP.Obj.OptionalHeader->Header.MajorImageVersion;374  Header->MinorImageVersion = CP.Obj.OptionalHeader->Header.MinorImageVersion;375  Header->MajorSubsystemVersion =376      CP.Obj.OptionalHeader->Header.MajorSubsystemVersion;377  Header->MinorSubsystemVersion =378      CP.Obj.OptionalHeader->Header.MinorSubsystemVersion;379  Header->SizeOfImage = SizeOfImage;380  Header->SizeOfHeaders = SizeOfHeaders;381  Header->Subsystem = CP.Obj.OptionalHeader->Header.Subsystem;382  Header->DLLCharacteristics = CP.Obj.OptionalHeader->Header.DLLCharacteristics;383  Header->SizeOfStackReserve = CP.Obj.OptionalHeader->Header.SizeOfStackReserve;384  Header->SizeOfStackCommit = CP.Obj.OptionalHeader->Header.SizeOfStackCommit;385  Header->SizeOfHeapReserve = CP.Obj.OptionalHeader->Header.SizeOfHeapReserve;386  Header->SizeOfHeapCommit = CP.Obj.OptionalHeader->Header.SizeOfHeapCommit;387  Header->NumberOfRvaAndSize = CP.Obj.OptionalHeader->Header.NumberOfRvaAndSize;388  return BaseOfData;389}390 391static bool writeCOFF(COFFParser &CP, raw_ostream &OS) {392  if (CP.isPE()) {393    // PE files start with a DOS stub.394    object::dos_header DH;395    memset(&DH, 0, sizeof(DH));396 397    // DOS EXEs start with "MZ" magic.398    DH.Magic[0] = 'M';399    DH.Magic[1] = 'Z';400    // Initializing the AddressOfRelocationTable is strictly optional but401    // mollifies certain tools which expect it to have a value greater than402    // 0x40.403    DH.AddressOfRelocationTable = sizeof(DH);404    // This is the address of the PE signature.405    DH.AddressOfNewExeHeader = DOSStubSize;406 407    // Write out our DOS stub.408    OS.write(reinterpret_cast<char *>(&DH), sizeof(DH));409    // Write padding until we reach the position of where our PE signature410    // should live.411    OS.write_zeros(DOSStubSize - sizeof(DH));412    // Write out the PE signature.413    OS.write(COFF::PEMagic, sizeof(COFF::PEMagic));414  }415  if (CP.useBigObj()) {416    OS << binary_le(static_cast<uint16_t>(COFF::IMAGE_FILE_MACHINE_UNKNOWN))417       << binary_le(static_cast<uint16_t>(0xffff))418       << binary_le(419              static_cast<uint16_t>(COFF::BigObjHeader::MinBigObjectVersion))420       << binary_le(CP.Obj.Header.Machine)421       << binary_le(CP.Obj.Header.TimeDateStamp);422    OS.write(COFF::BigObjMagic, sizeof(COFF::BigObjMagic));423    OS << zeros(uint32_t(0)) << zeros(uint32_t(0)) << zeros(uint32_t(0))424       << zeros(uint32_t(0)) << binary_le(CP.Obj.Header.NumberOfSections)425       << binary_le(CP.Obj.Header.PointerToSymbolTable)426       << binary_le(CP.Obj.Header.NumberOfSymbols);427  } else {428    OS << binary_le(CP.Obj.Header.Machine)429       << binary_le(static_cast<int16_t>(CP.Obj.Header.NumberOfSections))430       << binary_le(CP.Obj.Header.TimeDateStamp)431       << binary_le(CP.Obj.Header.PointerToSymbolTable)432       << binary_le(CP.Obj.Header.NumberOfSymbols)433       << binary_le(CP.Obj.Header.SizeOfOptionalHeader)434       << binary_le(CP.Obj.Header.Characteristics);435  }436  if (CP.isPE()) {437    if (CP.is64Bit()) {438      object::pe32plus_header PEH;439      initializeOptionalHeader(CP, COFF::PE32Header::PE32_PLUS, &PEH);440      OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));441    } else {442      object::pe32_header PEH;443      uint32_t BaseOfData =444          initializeOptionalHeader(CP, COFF::PE32Header::PE32, &PEH);445      PEH.BaseOfData = BaseOfData;446      OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));447    }448    for (uint32_t I = 0; I < CP.Obj.OptionalHeader->Header.NumberOfRvaAndSize;449         ++I) {450      const std::optional<COFF::DataDirectory> *DataDirectories =451          CP.Obj.OptionalHeader->DataDirectories;452      uint32_t NumDataDir = std::size(CP.Obj.OptionalHeader->DataDirectories);453      if (I >= NumDataDir || !DataDirectories[I]) {454        OS << zeros(uint32_t(0));455        OS << zeros(uint32_t(0));456      } else {457        OS << binary_le(DataDirectories[I]->RelativeVirtualAddress);458        OS << binary_le(DataDirectories[I]->Size);459      }460    }461  }462 463  assert(OS.tell() == CP.SectionTableStart);464  // Output section table.465  for (const COFFYAML::Section &S : CP.Obj.Sections) {466    OS.write(S.Header.Name, COFF::NameSize);467    OS << binary_le(S.Header.VirtualSize)468       << binary_le(S.Header.VirtualAddress)469       << binary_le(S.Header.SizeOfRawData)470       << binary_le(S.Header.PointerToRawData)471       << binary_le(S.Header.PointerToRelocations)472       << binary_le(S.Header.PointerToLineNumbers)473       << binary_le(S.Header.NumberOfRelocations)474       << binary_le(S.Header.NumberOfLineNumbers)475       << binary_le(S.Header.Characteristics);476  }477  assert(OS.tell() == CP.SectionTableStart + CP.SectionTableSize);478 479  unsigned CurSymbol = 0;480  StringMap<unsigned> SymbolTableIndexMap;481  for (const COFFYAML::Symbol &Sym : CP.Obj.Symbols) {482    SymbolTableIndexMap[Sym.Name] = CurSymbol;483    CurSymbol += 1 + Sym.Header.NumberOfAuxSymbols;484  }485 486  // Output section data.487  for (const COFFYAML::Section &S : CP.Obj.Sections) {488    if (S.Header.SizeOfRawData == 0 || S.Header.PointerToRawData == 0)489      continue;490    assert(S.Header.PointerToRawData >= OS.tell());491    OS.write_zeros(S.Header.PointerToRawData - OS.tell());492    for (auto E : S.StructuredData)493      E.writeAsBinary(OS);494    S.SectionData.writeAsBinary(OS);495    assert(S.Header.SizeOfRawData >= S.SectionData.binary_size());496    OS.write_zeros(S.Header.PointerToRawData + S.Header.SizeOfRawData -497                   OS.tell());498    if (S.Header.Characteristics & COFF::IMAGE_SCN_LNK_NRELOC_OVFL)499      OS << binary_le<uint32_t>(/*VirtualAddress=*/ S.Relocations.size() + 1)500         << binary_le<uint32_t>(/*SymbolTableIndex=*/ 0)501         << binary_le<uint16_t>(/*Type=*/ 0);502    for (const COFFYAML::Relocation &R : S.Relocations) {503      uint32_t SymbolTableIndex;504      if (R.SymbolTableIndex) {505        if (!R.SymbolName.empty())506          WithColor::error()507              << "Both SymbolName and SymbolTableIndex specified\n";508        SymbolTableIndex = *R.SymbolTableIndex;509      } else {510        SymbolTableIndex = SymbolTableIndexMap[R.SymbolName];511      }512      OS << binary_le(R.VirtualAddress) << binary_le(SymbolTableIndex)513         << binary_le(R.Type);514    }515  }516 517  // Output symbol table.518 519  for (std::vector<COFFYAML::Symbol>::const_iterator i = CP.Obj.Symbols.begin(),520                                                     e = CP.Obj.Symbols.end();521       i != e; ++i) {522    OS.write(i->Header.Name, COFF::NameSize);523    OS << binary_le(i->Header.Value);524    if (CP.useBigObj())525      OS << binary_le(i->Header.SectionNumber);526    else527      OS << binary_le(static_cast<int16_t>(i->Header.SectionNumber));528    OS << binary_le(i->Header.Type) << binary_le(i->Header.StorageClass)529       << binary_le(i->Header.NumberOfAuxSymbols);530 531    if (i->FunctionDefinition) {532      OS << binary_le(i->FunctionDefinition->TagIndex)533         << binary_le(i->FunctionDefinition->TotalSize)534         << binary_le(i->FunctionDefinition->PointerToLinenumber)535         << binary_le(i->FunctionDefinition->PointerToNextFunction)536         << zeros(i->FunctionDefinition->unused);537      OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);538    }539    if (i->bfAndefSymbol) {540      OS << zeros(i->bfAndefSymbol->unused1)541         << binary_le(i->bfAndefSymbol->Linenumber)542         << zeros(i->bfAndefSymbol->unused2)543         << binary_le(i->bfAndefSymbol->PointerToNextFunction)544         << zeros(i->bfAndefSymbol->unused3);545      OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);546    }547    if (i->WeakExternal) {548      OS << binary_le(i->WeakExternal->TagIndex)549         << binary_le(i->WeakExternal->Characteristics)550         << zeros(i->WeakExternal->unused);551      OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);552    }553    if (!i->File.empty()) {554      unsigned SymbolSize = CP.getSymbolSize();555      uint32_t NumberOfAuxRecords =556          (i->File.size() + SymbolSize - 1) / SymbolSize;557      uint32_t NumberOfAuxBytes = NumberOfAuxRecords * SymbolSize;558      uint32_t NumZeros = NumberOfAuxBytes - i->File.size();559      OS.write(i->File.data(), i->File.size());560      OS.write_zeros(NumZeros);561    }562    if (i->SectionDefinition) {563      OS << binary_le(i->SectionDefinition->Length)564         << binary_le(i->SectionDefinition->NumberOfRelocations)565         << binary_le(i->SectionDefinition->NumberOfLinenumbers)566         << binary_le(i->SectionDefinition->CheckSum)567         << binary_le(static_cast<int16_t>(i->SectionDefinition->Number))568         << binary_le(i->SectionDefinition->Selection)569         << zeros(i->SectionDefinition->unused)570         << binary_le(static_cast<int16_t>(i->SectionDefinition->Number >> 16));571      OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);572    }573    if (i->CLRToken) {574      OS << binary_le(i->CLRToken->AuxType) << zeros(i->CLRToken->unused1)575         << binary_le(i->CLRToken->SymbolTableIndex)576         << zeros(i->CLRToken->unused2);577      OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);578    }579  }580 581  // Output string table.582  if (CP.Obj.Header.PointerToSymbolTable)583    OS.write(&CP.StringTable[0], CP.StringTable.size());584  return true;585}586 587size_t COFFYAML::SectionDataEntry::size() const {588  size_t Size = Binary.binary_size();589  if (UInt32)590    Size += sizeof(*UInt32);591  if (LoadConfig32)592    Size += LoadConfig32->Size;593  if (LoadConfig64)594    Size += LoadConfig64->Size;595  return Size;596}597 598template <typename T> static void writeLoadConfig(T &S, raw_ostream &OS) {599  OS.write(reinterpret_cast<const char *>(&S),600           std::min(sizeof(S), static_cast<size_t>(S.Size)));601  if (sizeof(S) < S.Size)602    OS.write_zeros(S.Size - sizeof(S));603}604 605void COFFYAML::SectionDataEntry::writeAsBinary(raw_ostream &OS) const {606  if (UInt32)607    OS << binary_le(*UInt32);608  Binary.writeAsBinary(OS);609  if (LoadConfig32)610    writeLoadConfig(*LoadConfig32, OS);611  if (LoadConfig64)612    writeLoadConfig(*LoadConfig64, OS);613}614 615namespace llvm {616namespace yaml {617 618bool yaml2coff(llvm::COFFYAML::Object &Doc, raw_ostream &Out,619               ErrorHandler ErrHandler) {620  COFFParser CP(Doc, ErrHandler);621  if (!CP.parse()) {622    ErrHandler("failed to parse YAML file");623    return false;624  }625 626  if (!layoutOptionalHeader(CP)) {627    ErrHandler("failed to layout optional header for COFF file");628    return false;629  }630 631  if (!layoutCOFF(CP)) {632    ErrHandler("failed to layout COFF file");633    return false;634  }635  if (!writeCOFF(CP, Out)) {636    ErrHandler("failed to write COFF file");637    return false;638  }639  return true;640}641 642} // namespace yaml643} // namespace llvm644