tools/yaml2obj/yaml2coff.cpp

   1 //===- yaml2coff - Convert YAML to a COFF object file ---------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 ///
  10 /// \file
  11 /// \brief The COFF component of yaml2obj.
  12 ///
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "yaml2obj.h"
  16 #include "llvm/ADT/SmallString.h"
  17 #include "llvm/ADT/STLExtras.h"
  18 #include "llvm/ADT/StringExtras.h"
  19 #include "llvm/ADT/StringMap.h"
  20 #include "llvm/ADT/StringSwitch.h"
  21 #include "llvm/Object/COFFYAML.h"
  22 #include "llvm/Object/COFF.h"
  23 #include "llvm/Support/Endian.h"
  24 #include "llvm/Support/MemoryBuffer.h"
  25 #include "llvm/Support/SourceMgr.h"
  26 #include "llvm/Support/raw_ostream.h"
  27 #include <vector>
  28
  29 using namespace llvm;
  30
  31 /// This parses a yaml stream that represents a COFF object file.
  32 /// See docs/yaml2obj for the yaml scheema.
  33 struct COFFParser {
  34   COFFParser(COFFYAML::Object &Obj)
  35       : Obj(Obj), SectionTableStart(0), SectionTableSize(0) {
  36     // A COFF string table always starts with a 4 byte size field. Offsets into
  37     // 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.hasValue(); }
  47   bool is64Bit() const {
  48     return Obj.Header.Machine == COFF::IMAGE_FILE_MACHINE_AMD64;
  49   }
  50
  51   uint32_t getFileAlignment() const {
  52     return Obj.OptionalHeader->Header.FileAlignment;
  53   }
  54
  55   unsigned getHeaderSize() const {
  56     return useBigObj() ? COFF::Header32Size : COFF::Header16Size;
  57   }
  58
  59   unsigned getSymbolSize() const {
  60     return useBigObj() ? COFF::Symbol32Size : COFF::Symbol16Size;
  61   }
  62
  63   bool parseSections() {
  64     for (std::vector<COFFYAML::Section>::iterator i = Obj.Sections.begin(),
  65            e = Obj.Sections.end(); i != e; ++i) {
  66       COFFYAML::Section &Sec = *i;
  67
  68       // If the name is less than 8 bytes, store it in place, otherwise
  69       // store it in the string table.
  70       StringRef Name = Sec.Name;
  71
  72       if (Name.size() <= COFF::NameSize) {
  73         std::copy(Name.begin(), Name.end(), Sec.Header.Name);
  74       } else {
  75         // Add string to the string table and format the index for output.
  76         unsigned Index = getStringIndex(Name);
  77         std::string str = utostr(Index);
  78         if (str.size() > 7) {
  79           errs() << "String table got too large";
  80           return false;
  81         }
  82         Sec.Header.Name[0] = '/';
  83         std::copy(str.begin(), str.end(), Sec.Header.Name + 1);
  84       }
  85
  86       Sec.Header.Characteristics |= (Log2_32(Sec.Alignment) + 1) << 20;
  87     }
  88     return true;
  89   }
  90
  91   bool parseSymbols() {
  92     for (std::vector<COFFYAML::Symbol>::iterator i = Obj.Symbols.begin(),
  93            e = Obj.Symbols.end(); i != e; ++i) {
  94       COFFYAML::Symbol &Sym = *i;
  95
  96       // If the name is less than 8 bytes, store it in place, otherwise
  97       // store it in the string table.
  98       StringRef Name = Sym.Name;
  99       if (Name.size() <= COFF::NameSize) {
 100         std::copy(Name.begin(), Name.end(), Sym.Header.Name);
 101       } else {
 102         // Add string to the string table and format the index for output.
 103         unsigned Index = getStringIndex(Name);
 104         *reinterpret_cast<support::aligned_ulittle32_t*>(
 105             Sym.Header.Name + 4) = Index;
 106       }
 107
 108       Sym.Header.Type = Sym.SimpleType;
 109       Sym.Header.Type |= Sym.ComplexType << COFF::SCT_COMPLEX_TYPE_SHIFT;
 110     }
 111     return true;
 112   }
 113
 114   bool parse() {
 115     if (!parseSections())
 116       return false;
 117     if (!parseSymbols())
 118       return false;
 119     return true;
 120   }
 121
 122   unsigned getStringIndex(StringRef Str) {
 123     StringMap<unsigned>::iterator i = StringTableMap.find(Str);
 124     if (i == StringTableMap.end()) {
 125       unsigned Index = StringTable.size();
 126       StringTable.append(Str.begin(), Str.end());
 127       StringTable.push_back(0);
 128       StringTableMap[Str] = Index;
 129       return Index;
 130     }
 131     return i->second;
 132   }
 133
 134   COFFYAML::Object &Obj;
 135
 136   StringMap<unsigned> StringTableMap;
 137   std::string StringTable;
 138   uint32_t SectionTableStart;
 139   uint32_t SectionTableSize;
 140 };
 141
 142 // Take a CP and assign addresses and sizes to everything. Returns false if the
 143 // layout is not valid to do.
 144 static bool layoutOptionalHeader(COFFParser &CP) {
 145   if (!CP.isPE())
 146     return true;
 147   unsigned PEHeaderSize = CP.is64Bit() ? sizeof(object::pe32plus_header)
 148                                        : sizeof(object::pe32_header);
 149   CP.Obj.Header.SizeOfOptionalHeader =
 150       PEHeaderSize +
 151       sizeof(object::data_directory) * (COFF::NUM_DATA_DIRECTORIES + 1);
 152   return true;
 153 }
 154
 155 namespace {
 156 enum { DOSStubSize = 128 };
 157 }
 158
 159 // Take a CP and assign addresses and sizes to everything. Returns false if the
 160 // layout is not valid to do.
 161 static bool layoutCOFF(COFFParser &CP) {
 162   // The section table starts immediately after the header, including the
 163   // optional header.
 164   CP.SectionTableStart =
 165       CP.getHeaderSize() + CP.Obj.Header.SizeOfOptionalHeader;
 166   if (CP.isPE())
 167     CP.SectionTableStart += DOSStubSize + sizeof(COFF::PEMagic);
 168   CP.SectionTableSize = COFF::SectionSize * CP.Obj.Sections.size();
 169
 170   uint32_t CurrentSectionDataOffset =
 171       CP.SectionTableStart + CP.SectionTableSize;
 172
 173   // Assign each section data address consecutively.
 174   for (COFFYAML::Section &S : CP.Obj.Sections) {
 175     if (S.SectionData.binary_size() > 0) {
 176       CurrentSectionDataOffset = RoundUpToAlignment(
 177           CurrentSectionDataOffset, CP.isPE() ? CP.getFileAlignment() : 4);
 178       S.Header.SizeOfRawData = S.SectionData.binary_size();
 179       if (CP.isPE())
 180         S.Header.SizeOfRawData =
 181             RoundUpToAlignment(S.Header.SizeOfRawData, CP.getFileAlignment());
 182       S.Header.PointerToRawData = CurrentSectionDataOffset;
 183       CurrentSectionDataOffset += S.Header.SizeOfRawData;
 184       if (!S.Relocations.empty()) {
 185         S.Header.PointerToRelocations = CurrentSectionDataOffset;
 186         S.Header.NumberOfRelocations = S.Relocations.size();
 187         CurrentSectionDataOffset +=
 188             S.Header.NumberOfRelocations * COFF::RelocationSize;
 189       }
 190     } else {
 191       S.Header.SizeOfRawData = 0;
 192       S.Header.PointerToRawData = 0;
 193     }
 194   }
 195
 196   uint32_t SymbolTableStart = CurrentSectionDataOffset;
 197
 198   // Calculate number of symbols.
 199   uint32_t NumberOfSymbols = 0;
 200   for (std::vector<COFFYAML::Symbol>::iterator i = CP.Obj.Symbols.begin(),
 201                                                e = CP.Obj.Symbols.end();
 202                                                i != e; ++i) {
 203     uint32_t NumberOfAuxSymbols = 0;
 204     if (i->FunctionDefinition)
 205       NumberOfAuxSymbols += 1;
 206     if (i->bfAndefSymbol)
 207       NumberOfAuxSymbols += 1;
 208     if (i->WeakExternal)
 209       NumberOfAuxSymbols += 1;
 210     if (!i->File.empty())
 211       NumberOfAuxSymbols +=
 212           (i->File.size() + CP.getSymbolSize() - 1) / CP.getSymbolSize();
 213     if (i->SectionDefinition)
 214       NumberOfAuxSymbols += 1;
 215     if (i->CLRToken)
 216       NumberOfAuxSymbols += 1;
 217     i->Header.NumberOfAuxSymbols = NumberOfAuxSymbols;
 218     NumberOfSymbols += 1 + NumberOfAuxSymbols;
 219   }
 220
 221   // Store all the allocated start addresses in the header.
 222   CP.Obj.Header.NumberOfSections = CP.Obj.Sections.size();
 223   CP.Obj.Header.NumberOfSymbols = NumberOfSymbols;
 224   if (NumberOfSymbols > 0 || CP.StringTable.size() > 4)
 225     CP.Obj.Header.PointerToSymbolTable = SymbolTableStart;
 226   else
 227     CP.Obj.Header.PointerToSymbolTable = 0;
 228
 229   *reinterpret_cast<support::ulittle32_t *>(&CP.StringTable[0])
 230     = CP.StringTable.size();
 231
 232   return true;
 233 }
 234
 235 template <typename value_type>
 236 struct binary_le_impl {
 237   value_type Value;
 238   binary_le_impl(value_type V) : Value(V) {}
 239 };
 240
 241 template <typename value_type>
 242 raw_ostream &operator <<( raw_ostream &OS
 243                         , const binary_le_impl<value_type> &BLE) {
 244   char Buffer[sizeof(BLE.Value)];
 245   support::endian::write<value_type, support::little, support::unaligned>(
 246     Buffer, BLE.Value);
 247   OS.write(Buffer, sizeof(BLE.Value));
 248   return OS;
 249 }
 250
 251 template <typename value_type>
 252 binary_le_impl<value_type> binary_le(value_type V) {
 253   return binary_le_impl<value_type>(V);
 254 }
 255
 256 template <size_t NumBytes>
 257 struct zeros_impl {
 258   zeros_impl() {}
 259 };
 260
 261 template <size_t NumBytes>
 262 raw_ostream &operator<<(raw_ostream &OS, const zeros_impl<NumBytes> &) {
 263   char Buffer[NumBytes];
 264   memset(Buffer, 0, sizeof(Buffer));
 265   OS.write(Buffer, sizeof(Buffer));
 266   return OS;
 267 }
 268
 269 template <typename T>
 270 zeros_impl<sizeof(T)> zeros(const T &) {
 271   return zeros_impl<sizeof(T)>();
 272 }
 273
 274 struct num_zeros_impl {
 275   size_t N;
 276   num_zeros_impl(size_t N) : N(N) {}
 277 };
 278
 279 raw_ostream &operator<<(raw_ostream &OS, const num_zeros_impl &NZI) {
 280   for (size_t I = 0; I != NZI.N; ++I)
 281     OS.write(0);
 282   return OS;
 283 }
 284
 285 num_zeros_impl num_zeros(size_t N) {
 286   num_zeros_impl NZI(N);
 287   return NZI;
 288 }
 289
 290 template <typename T>
 291 static uint32_t initializeOptionalHeader(COFFParser &CP, uint16_t Magic, T Header) {
 292   memset(Header, 0, sizeof(*Header));
 293   Header->Magic = Magic;
 294   Header->SectionAlignment = CP.Obj.OptionalHeader->Header.SectionAlignment;
 295   Header->FileAlignment = CP.Obj.OptionalHeader->Header.FileAlignment;
 296   uint32_t SizeOfCode = 0, SizeOfInitializedData = 0,
 297            SizeOfUninitializedData = 0;
 298   uint32_t SizeOfHeaders = RoundUpToAlignment(
 299       CP.SectionTableStart + CP.SectionTableSize, Header->FileAlignment);
 300   uint32_t SizeOfImage =
 301       RoundUpToAlignment(SizeOfHeaders, Header->SectionAlignment);
 302   uint32_t BaseOfData = 0;
 303   for (const COFFYAML::Section &S : CP.Obj.Sections) {
 304     if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_CODE)
 305       SizeOfCode += S.Header.SizeOfRawData;
 306     if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
 307       SizeOfInitializedData += S.Header.SizeOfRawData;
 308     if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
 309       SizeOfUninitializedData += S.Header.SizeOfRawData;
 310     if (S.Name.equals(".text"))
 311       Header->BaseOfCode = S.Header.VirtualAddress; // RVA
 312     else if (S.Name.equals(".data"))
 313       BaseOfData = S.Header.VirtualAddress; // RVA
 314     if (S.Header.VirtualAddress)
 315       SizeOfImage +=
 316           RoundUpToAlignment(S.Header.VirtualSize, Header->SectionAlignment);
 317   }
 318   Header->SizeOfCode = SizeOfCode;
 319   Header->SizeOfInitializedData = SizeOfInitializedData;
 320   Header->SizeOfUninitializedData = SizeOfUninitializedData;
 321   Header->AddressOfEntryPoint =
 322       CP.Obj.OptionalHeader->Header.AddressOfEntryPoint; // RVA
 323   Header->ImageBase = CP.Obj.OptionalHeader->Header.ImageBase;
 324   Header->MajorOperatingSystemVersion =
 325       CP.Obj.OptionalHeader->Header.MajorOperatingSystemVersion;
 326   Header->MinorOperatingSystemVersion =
 327       CP.Obj.OptionalHeader->Header.MinorOperatingSystemVersion;
 328   Header->MajorImageVersion =
 329       CP.Obj.OptionalHeader->Header.MajorImageVersion;
 330   Header->MinorImageVersion =
 331       CP.Obj.OptionalHeader->Header.MinorImageVersion;
 332   Header->MajorSubsystemVersion =
 333       CP.Obj.OptionalHeader->Header.MajorSubsystemVersion;
 334   Header->MinorSubsystemVersion =
 335       CP.Obj.OptionalHeader->Header.MinorSubsystemVersion;
 336   Header->SizeOfImage = SizeOfImage;
 337   Header->SizeOfHeaders = SizeOfHeaders;
 338   Header->Subsystem = CP.Obj.OptionalHeader->Header.Subsystem;
 339   Header->DLLCharacteristics = CP.Obj.OptionalHeader->Header.DLLCharacteristics;
 340   Header->SizeOfStackReserve = CP.Obj.OptionalHeader->Header.SizeOfStackReserve;
 341   Header->SizeOfStackCommit = CP.Obj.OptionalHeader->Header.SizeOfStackCommit;
 342   Header->SizeOfHeapReserve = CP.Obj.OptionalHeader->Header.SizeOfHeapReserve;
 343   Header->SizeOfHeapCommit = CP.Obj.OptionalHeader->Header.SizeOfHeapCommit;
 344   Header->NumberOfRvaAndSize = COFF::NUM_DATA_DIRECTORIES + 1;
 345   return BaseOfData;
 346 }
 347
 348 static bool writeCOFF(COFFParser &CP, raw_ostream &OS) {
 349   if (CP.isPE()) {
 350     // PE files start with a DOS stub.
 351     object::dos_header DH;
 352     memset(&DH, 0, sizeof(DH));
 353
 354     // DOS EXEs start with "MZ" magic.
 355     DH.Magic[0] = 'M';
 356     DH.Magic[1] = 'Z';
 357     // Initializing the AddressOfRelocationTable is strictly optional but
 358     // mollifies certain tools which expect it to have a value greater than
 359     // 0x40.
 360     DH.AddressOfRelocationTable = sizeof(DH);
 361     // This is the address of the PE signature.
 362     DH.AddressOfNewExeHeader = DOSStubSize;
 363
 364     // Write out our DOS stub.
 365     OS.write(reinterpret_cast<char *>(&DH), sizeof(DH));
 366     // Write padding until we reach the position of where our PE signature
 367     // should live.
 368     OS << num_zeros(DOSStubSize - sizeof(DH));
 369     // Write out the PE signature.
 370     OS.write(COFF::PEMagic, sizeof(COFF::PEMagic));
 371   }
 372   if (CP.useBigObj()) {
 373     OS << binary_le(static_cast<uint16_t>(COFF::IMAGE_FILE_MACHINE_UNKNOWN))
 374        << binary_le(static_cast<uint16_t>(0xffff))
 375        << binary_le(static_cast<uint16_t>(COFF::BigObjHeader::MinBigObjectVersion))
 376        << binary_le(CP.Obj.Header.Machine)
 377        << binary_le(CP.Obj.Header.TimeDateStamp);
 378     OS.write(COFF::BigObjMagic, sizeof(COFF::BigObjMagic));
 379     OS << zeros(uint32_t(0))
 380        << zeros(uint32_t(0))
 381        << zeros(uint32_t(0))
 382        << zeros(uint32_t(0))
 383        << binary_le(CP.Obj.Header.NumberOfSections)
 384        << binary_le(CP.Obj.Header.PointerToSymbolTable)
 385        << binary_le(CP.Obj.Header.NumberOfSymbols);
 386   } else {
 387     OS << binary_le(CP.Obj.Header.Machine)
 388        << binary_le(static_cast<int16_t>(CP.Obj.Header.NumberOfSections))
 389        << binary_le(CP.Obj.Header.TimeDateStamp)
 390        << binary_le(CP.Obj.Header.PointerToSymbolTable)
 391        << binary_le(CP.Obj.Header.NumberOfSymbols)
 392        << binary_le(CP.Obj.Header.SizeOfOptionalHeader)
 393        << binary_le(CP.Obj.Header.Characteristics);
 394   }
 395   if (CP.isPE()) {
 396     if (CP.is64Bit()) {
 397       object::pe32plus_header PEH;
 398       initializeOptionalHeader(CP, COFF::PE32Header::PE32_PLUS, &PEH);
 399       OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));
 400     } else {
 401       object::pe32_header PEH;
 402       uint32_t BaseOfData = initializeOptionalHeader(CP, COFF::PE32Header::PE32, &PEH);
 403       PEH.BaseOfData = BaseOfData;
 404       OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));
 405     }
 406     for (const Optional<COFF::DataDirectory> &DD :
 407          CP.Obj.OptionalHeader->DataDirectories) {
 408       if (!DD.hasValue()) {
 409         OS << zeros(uint32_t(0));
 410         OS << zeros(uint32_t(0));
 411       } else {
 412         OS << binary_le(DD->RelativeVirtualAddress);
 413         OS << binary_le(DD->Size);
 414       }
 415     }
 416     OS << zeros(uint32_t(0));
 417     OS << zeros(uint32_t(0));
 418   }
 419
 420   assert(OS.tell() == CP.SectionTableStart);
 421   // Output section table.
 422   for (std::vector<COFFYAML::Section>::iterator i = CP.Obj.Sections.begin(),
 423                                                 e = CP.Obj.Sections.end();
 424                                                 i != e; ++i) {
 425     OS.write(i->Header.Name, COFF::NameSize);
 426     OS << binary_le(i->Header.VirtualSize)
 427        << binary_le(i->Header.VirtualAddress)
 428        << binary_le(i->Header.SizeOfRawData)
 429        << binary_le(i->Header.PointerToRawData)
 430        << binary_le(i->Header.PointerToRelocations)
 431        << binary_le(i->Header.PointerToLineNumbers)
 432        << binary_le(i->Header.NumberOfRelocations)
 433        << binary_le(i->Header.NumberOfLineNumbers)
 434        << binary_le(i->Header.Characteristics);
 435   }
 436   assert(OS.tell() == CP.SectionTableStart + CP.SectionTableSize);
 437
 438   unsigned CurSymbol = 0;
 439   StringMap<unsigned> SymbolTableIndexMap;
 440   for (std::vector<COFFYAML::Symbol>::iterator I = CP.Obj.Symbols.begin(),
 441                                                E = CP.Obj.Symbols.end();
 442        I != E; ++I) {
 443     SymbolTableIndexMap[I->Name] = CurSymbol;
 444     CurSymbol += 1 + I->Header.NumberOfAuxSymbols;
 445   }
 446
 447   // Output section data.
 448   for (const COFFYAML::Section &S : CP.Obj.Sections) {
 449     if (!S.Header.SizeOfRawData)
 450       continue;
 451     assert(S.Header.PointerToRawData >= OS.tell());
 452     OS << num_zeros(S.Header.PointerToRawData - OS.tell());
 453     S.SectionData.writeAsBinary(OS);
 454     assert(S.Header.SizeOfRawData >= S.SectionData.binary_size());
 455     OS << num_zeros(S.Header.SizeOfRawData - S.SectionData.binary_size());
 456     for (const COFFYAML::Relocation &R : S.Relocations) {
 457       uint32_t SymbolTableIndex = SymbolTableIndexMap[R.SymbolName];
 458       OS << binary_le(R.VirtualAddress)
 459          << binary_le(SymbolTableIndex)
 460          << binary_le(R.Type);
 461     }
 462   }
 463
 464   // Output symbol table.
 465
 466   for (std::vector<COFFYAML::Symbol>::const_iterator i = CP.Obj.Symbols.begin(),
 467                                                      e = CP.Obj.Symbols.end();
 468                                                      i != e; ++i) {
 469     OS.write(i->Header.Name, COFF::NameSize);
 470     OS << binary_le(i->Header.Value);
 471     if (CP.useBigObj())
 472        OS << binary_le(i->Header.SectionNumber);
 473     else
 474        OS << binary_le(static_cast<int16_t>(i->Header.SectionNumber));
 475     OS << binary_le(i->Header.Type)
 476        << binary_le(i->Header.StorageClass)
 477        << binary_le(i->Header.NumberOfAuxSymbols);
 478
 479     if (i->FunctionDefinition)
 480       OS << binary_le(i->FunctionDefinition->TagIndex)
 481          << binary_le(i->FunctionDefinition->TotalSize)
 482          << binary_le(i->FunctionDefinition->PointerToLinenumber)
 483          << binary_le(i->FunctionDefinition->PointerToNextFunction)
 484          << zeros(i->FunctionDefinition->unused)
 485          << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
 486     if (i->bfAndefSymbol)
 487       OS << zeros(i->bfAndefSymbol->unused1)
 488          << binary_le(i->bfAndefSymbol->Linenumber)
 489          << zeros(i->bfAndefSymbol->unused2)
 490          << binary_le(i->bfAndefSymbol->PointerToNextFunction)
 491          << zeros(i->bfAndefSymbol->unused3)
 492          << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
 493     if (i->WeakExternal)
 494       OS << binary_le(i->WeakExternal->TagIndex)
 495          << binary_le(i->WeakExternal->Characteristics)
 496          << zeros(i->WeakExternal->unused)
 497          << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
 498     if (!i->File.empty()) {
 499       unsigned SymbolSize = CP.getSymbolSize();
 500       uint32_t NumberOfAuxRecords =
 501           (i->File.size() + SymbolSize - 1) / SymbolSize;
 502       uint32_t NumberOfAuxBytes = NumberOfAuxRecords * SymbolSize;
 503       uint32_t NumZeros = NumberOfAuxBytes - i->File.size();
 504       OS.write(i->File.data(), i->File.size());
 505       OS << num_zeros(NumZeros);
 506     }
 507     if (i->SectionDefinition)
 508       OS << binary_le(i->SectionDefinition->Length)
 509          << binary_le(i->SectionDefinition->NumberOfRelocations)
 510          << binary_le(i->SectionDefinition->NumberOfLinenumbers)
 511          << binary_le(i->SectionDefinition->CheckSum)
 512          << binary_le(static_cast<int16_t>(i->SectionDefinition->Number))
 513          << binary_le(i->SectionDefinition->Selection)
 514          << zeros(i->SectionDefinition->unused)
 515          << binary_le(static_cast<int16_t>(i->SectionDefinition->Number >> 16))
 516          << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
 517     if (i->CLRToken)
 518       OS << binary_le(i->CLRToken->AuxType)
 519          << zeros(i->CLRToken->unused1)
 520          << binary_le(i->CLRToken->SymbolTableIndex)
 521          << zeros(i->CLRToken->unused2)
 522          << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
 523   }
 524
 525   // Output string table.
 526   if (CP.Obj.Header.PointerToSymbolTable)
 527     OS.write(&CP.StringTable[0], CP.StringTable.size());
 528   return true;
 529 }
 530
 531 int yaml2coff(yaml::Input &YIn, raw_ostream &Out) {
 532   COFFYAML::Object Doc;
 533   YIn >> Doc;
 534   if (YIn.error()) {
 535     errs() << "yaml2obj: Failed to parse YAML file!\n";
 536     return 1;
 537   }
 538
 539   COFFParser CP(Doc);
 540   if (!CP.parse()) {
 541     errs() << "yaml2obj: Failed to parse YAML file!\n";
 542     return 1;
 543   }
 544
 545   if (!layoutOptionalHeader(CP)) {
 546     errs() << "yaml2obj: Failed to layout optional header for COFF file!\n";
 547     return 1;
 548   }
 549   if (!layoutCOFF(CP)) {
 550     errs() << "yaml2obj: Failed to layout COFF file!\n";
 551     return 1;
 552   }
 553   if (!writeCOFF(CP, Out)) {
 554     errs() << "yaml2obj: Failed to write COFF file!\n";
 555     return 1;
 556   }
 557   return 0;
 558 }