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/STLExtras.h"
17#include "llvm/ADT/SmallString.h"
18#include "llvm/ADT/StringExtras.h"
19#include "llvm/ADT/StringMap.h"
20#include "llvm/ADT/StringSwitch.h"
21#include "llvm/Object/COFF.h"
22#include "llvm/Object/COFFYAML.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
29using namespace llvm;
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)
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.
144static 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
155namespace {
156enum { 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.
161static 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
235template <typename value_type>
236struct binary_le_impl {
237  value_type Value;
238  binary_le_impl(value_type V) : Value(V) {}
239};
240
241template <typename value_type>
242raw_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
251template <typename value_type>
252binary_le_impl<value_type> binary_le(value_type V) {
253  return binary_le_impl<value_type>(V);
254}
255
256template <size_t NumBytes> struct zeros_impl {};
257
258template <size_t NumBytes>
259raw_ostream &operator<<(raw_ostream &OS, const zeros_impl<NumBytes> &) {
260  char Buffer[NumBytes];
261  memset(Buffer, 0, sizeof(Buffer));
262  OS.write(Buffer, sizeof(Buffer));
263  return OS;
264}
265
266template <typename T>
267zeros_impl<sizeof(T)> zeros(const T &) {
268  return zeros_impl<sizeof(T)>();
269}
270
271struct num_zeros_impl {
272  size_t N;
273  num_zeros_impl(size_t N) : N(N) {}
274};
275
276raw_ostream &operator<<(raw_ostream &OS, const num_zeros_impl &NZI) {
277  for (size_t I = 0; I != NZI.N; ++I)
278    OS.write(0);
279  return OS;
280}
281
282static num_zeros_impl num_zeros(size_t N) {
283  num_zeros_impl NZI(N);
284  return NZI;
285}
286
287template <typename T>
288static uint32_t initializeOptionalHeader(COFFParser &CP, uint16_t Magic, T Header) {
289  memset(Header, 0, sizeof(*Header));
290  Header->Magic = Magic;
291  Header->SectionAlignment = CP.Obj.OptionalHeader->Header.SectionAlignment;
292  Header->FileAlignment = CP.Obj.OptionalHeader->Header.FileAlignment;
293  uint32_t SizeOfCode = 0, SizeOfInitializedData = 0,
294           SizeOfUninitializedData = 0;
295  uint32_t SizeOfHeaders = RoundUpToAlignment(
296      CP.SectionTableStart + CP.SectionTableSize, Header->FileAlignment);
297  uint32_t SizeOfImage =
298      RoundUpToAlignment(SizeOfHeaders, Header->SectionAlignment);
299  uint32_t BaseOfData = 0;
300  for (const COFFYAML::Section &S : CP.Obj.Sections) {
301    if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_CODE)
302      SizeOfCode += S.Header.SizeOfRawData;
303    if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
304      SizeOfInitializedData += S.Header.SizeOfRawData;
305    if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
306      SizeOfUninitializedData += S.Header.SizeOfRawData;
307    if (S.Name.equals(".text"))
308      Header->BaseOfCode = S.Header.VirtualAddress; // RVA
309    else if (S.Name.equals(".data"))
310      BaseOfData = S.Header.VirtualAddress; // RVA
311    if (S.Header.VirtualAddress)
312      SizeOfImage +=
313          RoundUpToAlignment(S.Header.VirtualSize, Header->SectionAlignment);
314  }
315  Header->SizeOfCode = SizeOfCode;
316  Header->SizeOfInitializedData = SizeOfInitializedData;
317  Header->SizeOfUninitializedData = SizeOfUninitializedData;
318  Header->AddressOfEntryPoint =
319      CP.Obj.OptionalHeader->Header.AddressOfEntryPoint; // RVA
320  Header->ImageBase = CP.Obj.OptionalHeader->Header.ImageBase;
321  Header->MajorOperatingSystemVersion =
322      CP.Obj.OptionalHeader->Header.MajorOperatingSystemVersion;
323  Header->MinorOperatingSystemVersion =
324      CP.Obj.OptionalHeader->Header.MinorOperatingSystemVersion;
325  Header->MajorImageVersion =
326      CP.Obj.OptionalHeader->Header.MajorImageVersion;
327  Header->MinorImageVersion =
328      CP.Obj.OptionalHeader->Header.MinorImageVersion;
329  Header->MajorSubsystemVersion =
330      CP.Obj.OptionalHeader->Header.MajorSubsystemVersion;
331  Header->MinorSubsystemVersion =
332      CP.Obj.OptionalHeader->Header.MinorSubsystemVersion;
333  Header->SizeOfImage = SizeOfImage;
334  Header->SizeOfHeaders = SizeOfHeaders;
335  Header->Subsystem = CP.Obj.OptionalHeader->Header.Subsystem;
336  Header->DLLCharacteristics = CP.Obj.OptionalHeader->Header.DLLCharacteristics;
337  Header->SizeOfStackReserve = CP.Obj.OptionalHeader->Header.SizeOfStackReserve;
338  Header->SizeOfStackCommit = CP.Obj.OptionalHeader->Header.SizeOfStackCommit;
339  Header->SizeOfHeapReserve = CP.Obj.OptionalHeader->Header.SizeOfHeapReserve;
340  Header->SizeOfHeapCommit = CP.Obj.OptionalHeader->Header.SizeOfHeapCommit;
341  Header->NumberOfRvaAndSize = COFF::NUM_DATA_DIRECTORIES + 1;
342  return BaseOfData;
343}
344
345static bool writeCOFF(COFFParser &CP, raw_ostream &OS) {
346  if (CP.isPE()) {
347    // PE files start with a DOS stub.
348    object::dos_header DH;
349    memset(&DH, 0, sizeof(DH));
350
351    // DOS EXEs start with "MZ" magic.
352    DH.Magic[0] = 'M';
353    DH.Magic[1] = 'Z';
354    // Initializing the AddressOfRelocationTable is strictly optional but
355    // mollifies certain tools which expect it to have a value greater than
356    // 0x40.
357    DH.AddressOfRelocationTable = sizeof(DH);
358    // This is the address of the PE signature.
359    DH.AddressOfNewExeHeader = DOSStubSize;
360
361    // Write out our DOS stub.
362    OS.write(reinterpret_cast<char *>(&DH), sizeof(DH));
363    // Write padding until we reach the position of where our PE signature
364    // should live.
365    OS << num_zeros(DOSStubSize - sizeof(DH));
366    // Write out the PE signature.
367    OS.write(COFF::PEMagic, sizeof(COFF::PEMagic));
368  }
369  if (CP.useBigObj()) {
370    OS << binary_le(static_cast<uint16_t>(COFF::IMAGE_FILE_MACHINE_UNKNOWN))
371       << binary_le(static_cast<uint16_t>(0xffff))
372       << binary_le(static_cast<uint16_t>(COFF::BigObjHeader::MinBigObjectVersion))
373       << binary_le(CP.Obj.Header.Machine)
374       << binary_le(CP.Obj.Header.TimeDateStamp);
375    OS.write(COFF::BigObjMagic, sizeof(COFF::BigObjMagic));
376    OS << zeros(uint32_t(0))
377       << zeros(uint32_t(0))
378       << zeros(uint32_t(0))
379       << zeros(uint32_t(0))
380       << binary_le(CP.Obj.Header.NumberOfSections)
381       << binary_le(CP.Obj.Header.PointerToSymbolTable)
382       << binary_le(CP.Obj.Header.NumberOfSymbols);
383  } else {
384    OS << binary_le(CP.Obj.Header.Machine)
385       << binary_le(static_cast<int16_t>(CP.Obj.Header.NumberOfSections))
386       << binary_le(CP.Obj.Header.TimeDateStamp)
387       << binary_le(CP.Obj.Header.PointerToSymbolTable)
388       << binary_le(CP.Obj.Header.NumberOfSymbols)
389       << binary_le(CP.Obj.Header.SizeOfOptionalHeader)
390       << binary_le(CP.Obj.Header.Characteristics);
391  }
392  if (CP.isPE()) {
393    if (CP.is64Bit()) {
394      object::pe32plus_header PEH;
395      initializeOptionalHeader(CP, COFF::PE32Header::PE32_PLUS, &PEH);
396      OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));
397    } else {
398      object::pe32_header PEH;
399      uint32_t BaseOfData = initializeOptionalHeader(CP, COFF::PE32Header::PE32, &PEH);
400      PEH.BaseOfData = BaseOfData;
401      OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));
402    }
403    for (const Optional<COFF::DataDirectory> &DD :
404         CP.Obj.OptionalHeader->DataDirectories) {
405      if (!DD.hasValue()) {
406        OS << zeros(uint32_t(0));
407        OS << zeros(uint32_t(0));
408      } else {
409        OS << binary_le(DD->RelativeVirtualAddress);
410        OS << binary_le(DD->Size);
411      }
412    }
413    OS << zeros(uint32_t(0));
414    OS << zeros(uint32_t(0));
415  }
416
417  assert(OS.tell() == CP.SectionTableStart);
418  // Output section table.
419  for (std::vector<COFFYAML::Section>::iterator i = CP.Obj.Sections.begin(),
420                                                e = CP.Obj.Sections.end();
421                                                i != e; ++i) {
422    OS.write(i->Header.Name, COFF::NameSize);
423    OS << binary_le(i->Header.VirtualSize)
424       << binary_le(i->Header.VirtualAddress)
425       << binary_le(i->Header.SizeOfRawData)
426       << binary_le(i->Header.PointerToRawData)
427       << binary_le(i->Header.PointerToRelocations)
428       << binary_le(i->Header.PointerToLineNumbers)
429       << binary_le(i->Header.NumberOfRelocations)
430       << binary_le(i->Header.NumberOfLineNumbers)
431       << binary_le(i->Header.Characteristics);
432  }
433  assert(OS.tell() == CP.SectionTableStart + CP.SectionTableSize);
434
435  unsigned CurSymbol = 0;
436  StringMap<unsigned> SymbolTableIndexMap;
437  for (std::vector<COFFYAML::Symbol>::iterator I = CP.Obj.Symbols.begin(),
438                                               E = CP.Obj.Symbols.end();
439       I != E; ++I) {
440    SymbolTableIndexMap[I->Name] = CurSymbol;
441    CurSymbol += 1 + I->Header.NumberOfAuxSymbols;
442  }
443
444  // Output section data.
445  for (const COFFYAML::Section &S : CP.Obj.Sections) {
446    if (!S.Header.SizeOfRawData)
447      continue;
448    assert(S.Header.PointerToRawData >= OS.tell());
449    OS << num_zeros(S.Header.PointerToRawData - OS.tell());
450    S.SectionData.writeAsBinary(OS);
451    assert(S.Header.SizeOfRawData >= S.SectionData.binary_size());
452    OS << num_zeros(S.Header.SizeOfRawData - S.SectionData.binary_size());
453    for (const COFFYAML::Relocation &R : S.Relocations) {
454      uint32_t SymbolTableIndex = SymbolTableIndexMap[R.SymbolName];
455      OS << binary_le(R.VirtualAddress)
456         << binary_le(SymbolTableIndex)
457         << binary_le(R.Type);
458    }
459  }
460
461  // Output symbol table.
462
463  for (std::vector<COFFYAML::Symbol>::const_iterator i = CP.Obj.Symbols.begin(),
464                                                     e = CP.Obj.Symbols.end();
465                                                     i != e; ++i) {
466    OS.write(i->Header.Name, COFF::NameSize);
467    OS << binary_le(i->Header.Value);
468    if (CP.useBigObj())
469       OS << binary_le(i->Header.SectionNumber);
470    else
471       OS << binary_le(static_cast<int16_t>(i->Header.SectionNumber));
472    OS << binary_le(i->Header.Type)
473       << binary_le(i->Header.StorageClass)
474       << binary_le(i->Header.NumberOfAuxSymbols);
475
476    if (i->FunctionDefinition)
477      OS << binary_le(i->FunctionDefinition->TagIndex)
478         << binary_le(i->FunctionDefinition->TotalSize)
479         << binary_le(i->FunctionDefinition->PointerToLinenumber)
480         << binary_le(i->FunctionDefinition->PointerToNextFunction)
481         << zeros(i->FunctionDefinition->unused)
482         << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
483    if (i->bfAndefSymbol)
484      OS << zeros(i->bfAndefSymbol->unused1)
485         << binary_le(i->bfAndefSymbol->Linenumber)
486         << zeros(i->bfAndefSymbol->unused2)
487         << binary_le(i->bfAndefSymbol->PointerToNextFunction)
488         << zeros(i->bfAndefSymbol->unused3)
489         << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
490    if (i->WeakExternal)
491      OS << binary_le(i->WeakExternal->TagIndex)
492         << binary_le(i->WeakExternal->Characteristics)
493         << zeros(i->WeakExternal->unused)
494         << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
495    if (!i->File.empty()) {
496      unsigned SymbolSize = CP.getSymbolSize();
497      uint32_t NumberOfAuxRecords =
498          (i->File.size() + SymbolSize - 1) / SymbolSize;
499      uint32_t NumberOfAuxBytes = NumberOfAuxRecords * SymbolSize;
500      uint32_t NumZeros = NumberOfAuxBytes - i->File.size();
501      OS.write(i->File.data(), i->File.size());
502      OS << num_zeros(NumZeros);
503    }
504    if (i->SectionDefinition)
505      OS << binary_le(i->SectionDefinition->Length)
506         << binary_le(i->SectionDefinition->NumberOfRelocations)
507         << binary_le(i->SectionDefinition->NumberOfLinenumbers)
508         << binary_le(i->SectionDefinition->CheckSum)
509         << binary_le(static_cast<int16_t>(i->SectionDefinition->Number))
510         << binary_le(i->SectionDefinition->Selection)
511         << zeros(i->SectionDefinition->unused)
512         << binary_le(static_cast<int16_t>(i->SectionDefinition->Number >> 16))
513         << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
514    if (i->CLRToken)
515      OS << binary_le(i->CLRToken->AuxType)
516         << zeros(i->CLRToken->unused1)
517         << binary_le(i->CLRToken->SymbolTableIndex)
518         << zeros(i->CLRToken->unused2)
519         << num_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
520  }
521
522  // Output string table.
523  if (CP.Obj.Header.PointerToSymbolTable)
524    OS.write(&CP.StringTable[0], CP.StringTable.size());
525  return true;
526}
527
528int yaml2coff(yaml::Input &YIn, raw_ostream &Out) {
529  COFFYAML::Object Doc;
530  YIn >> Doc;
531  if (YIn.error()) {
532    errs() << "yaml2obj: Failed to parse YAML file!\n";
533    return 1;
534  }
535
536  COFFParser CP(Doc);
537  if (!CP.parse()) {
538    errs() << "yaml2obj: Failed to parse YAML file!\n";
539    return 1;
540  }
541
542  if (!layoutOptionalHeader(CP)) {
543    errs() << "yaml2obj: Failed to layout optional header for COFF file!\n";
544    return 1;
545  }
546  if (!layoutCOFF(CP)) {
547    errs() << "yaml2obj: Failed to layout COFF file!\n";
548    return 1;
549  }
550  if (!writeCOFF(CP, Out)) {
551    errs() << "yaml2obj: Failed to write COFF file!\n";
552    return 1;
553  }
554  return 0;
555}
556