xref: /freebsd/contrib/llvm-project/llvm/lib/ObjectYAML/COFFEmitter.cpp (revision 9dba64be9536c28e4800e06512b7f29b43ade345)
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-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// The COFF component of yaml2obj.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/ADT/STLExtras.h"
15 #include "llvm/ADT/StringExtras.h"
16 #include "llvm/ADT/StringMap.h"
17 #include "llvm/ADT/StringSwitch.h"
18 #include "llvm/DebugInfo/CodeView/DebugStringTableSubsection.h"
19 #include "llvm/DebugInfo/CodeView/StringsAndChecksums.h"
20 #include "llvm/Object/COFF.h"
21 #include "llvm/ObjectYAML/ObjectYAML.h"
22 #include "llvm/ObjectYAML/yaml2obj.h"
23 #include "llvm/Support/Endian.h"
24 #include "llvm/Support/MemoryBuffer.h"
25 #include "llvm/Support/SourceMgr.h"
26 #include "llvm/Support/WithColor.h"
27 #include "llvm/Support/raw_ostream.h"
28 #include <vector>
29 
30 using namespace llvm;
31 
32 namespace {
33 
34 /// This parses a yaml stream that represents a COFF object file.
35 /// See docs/yaml2obj for the yaml scheema.
36 struct COFFParser {
37   COFFParser(COFFYAML::Object &Obj, yaml::ErrorHandler EH)
38       : Obj(Obj), SectionTableStart(0), SectionTableSize(0), ErrHandler(EH) {
39     // A COFF string table always starts with a 4 byte size field. Offsets into
40     // it include this size, so allocate it now.
41     StringTable.append(4, char(0));
42   }
43 
44   bool useBigObj() const {
45     return static_cast<int32_t>(Obj.Sections.size()) >
46            COFF::MaxNumberOfSections16;
47   }
48 
49   bool isPE() const { return Obj.OptionalHeader.hasValue(); }
50   bool is64Bit() const {
51     return Obj.Header.Machine == COFF::IMAGE_FILE_MACHINE_AMD64 ||
52            Obj.Header.Machine == COFF::IMAGE_FILE_MACHINE_ARM64;
53   }
54 
55   uint32_t getFileAlignment() const {
56     return Obj.OptionalHeader->Header.FileAlignment;
57   }
58 
59   unsigned getHeaderSize() const {
60     return useBigObj() ? COFF::Header32Size : COFF::Header16Size;
61   }
62 
63   unsigned getSymbolSize() const {
64     return useBigObj() ? COFF::Symbol32Size : COFF::Symbol16Size;
65   }
66 
67   bool parseSections() {
68     for (std::vector<COFFYAML::Section>::iterator i = Obj.Sections.begin(),
69                                                   e = Obj.Sections.end();
70          i != e; ++i) {
71       COFFYAML::Section &Sec = *i;
72 
73       // If the name is less than 8 bytes, store it in place, otherwise
74       // store it in the string table.
75       StringRef Name = Sec.Name;
76 
77       if (Name.size() <= COFF::NameSize) {
78         std::copy(Name.begin(), Name.end(), Sec.Header.Name);
79       } else {
80         // Add string to the string table and format the index for output.
81         unsigned Index = getStringIndex(Name);
82         std::string str = utostr(Index);
83         if (str.size() > 7) {
84           ErrHandler("string table got too large");
85           return false;
86         }
87         Sec.Header.Name[0] = '/';
88         std::copy(str.begin(), str.end(), Sec.Header.Name + 1);
89       }
90 
91       if (Sec.Alignment) {
92         if (Sec.Alignment > 8192) {
93           ErrHandler("section alignment is too large");
94           return false;
95         }
96         if (!isPowerOf2_32(Sec.Alignment)) {
97           ErrHandler("section alignment is not a power of 2");
98           return false;
99         }
100         Sec.Header.Characteristics |= (Log2_32(Sec.Alignment) + 1) << 20;
101       }
102     }
103     return true;
104   }
105 
106   bool parseSymbols() {
107     for (std::vector<COFFYAML::Symbol>::iterator i = Obj.Symbols.begin(),
108                                                  e = Obj.Symbols.end();
109          i != e; ++i) {
110       COFFYAML::Symbol &Sym = *i;
111 
112       // If the name is less than 8 bytes, store it in place, otherwise
113       // store it in the string table.
114       StringRef Name = Sym.Name;
115       if (Name.size() <= COFF::NameSize) {
116         std::copy(Name.begin(), Name.end(), Sym.Header.Name);
117       } else {
118         // Add string to the string table and format the index for output.
119         unsigned Index = getStringIndex(Name);
120         *reinterpret_cast<support::aligned_ulittle32_t *>(Sym.Header.Name + 4) =
121             Index;
122       }
123 
124       Sym.Header.Type = Sym.SimpleType;
125       Sym.Header.Type |= Sym.ComplexType << COFF::SCT_COMPLEX_TYPE_SHIFT;
126     }
127     return true;
128   }
129 
130   bool parse() {
131     if (!parseSections())
132       return false;
133     if (!parseSymbols())
134       return false;
135     return true;
136   }
137 
138   unsigned getStringIndex(StringRef Str) {
139     StringMap<unsigned>::iterator i = StringTableMap.find(Str);
140     if (i == StringTableMap.end()) {
141       unsigned Index = StringTable.size();
142       StringTable.append(Str.begin(), Str.end());
143       StringTable.push_back(0);
144       StringTableMap[Str] = Index;
145       return Index;
146     }
147     return i->second;
148   }
149 
150   COFFYAML::Object &Obj;
151 
152   codeview::StringsAndChecksums StringsAndChecksums;
153   BumpPtrAllocator Allocator;
154   StringMap<unsigned> StringTableMap;
155   std::string StringTable;
156   uint32_t SectionTableStart;
157   uint32_t SectionTableSize;
158 
159   yaml::ErrorHandler ErrHandler;
160 };
161 
162 enum { DOSStubSize = 128 };
163 
164 } // end anonymous namespace
165 
166 // Take a CP and assign addresses and sizes to everything. Returns false if the
167 // layout is not valid to do.
168 static bool layoutOptionalHeader(COFFParser &CP) {
169   if (!CP.isPE())
170     return true;
171   unsigned PEHeaderSize = CP.is64Bit() ? sizeof(object::pe32plus_header)
172                                        : sizeof(object::pe32_header);
173   CP.Obj.Header.SizeOfOptionalHeader =
174       PEHeaderSize +
175       sizeof(object::data_directory) * (COFF::NUM_DATA_DIRECTORIES + 1);
176   return true;
177 }
178 
179 static yaml::BinaryRef
180 toDebugS(ArrayRef<CodeViewYAML::YAMLDebugSubsection> Subsections,
181          const codeview::StringsAndChecksums &SC, BumpPtrAllocator &Allocator) {
182   using namespace codeview;
183   ExitOnError Err("Error occurred writing .debug$S section");
184   auto CVSS =
185       Err(CodeViewYAML::toCodeViewSubsectionList(Allocator, Subsections, SC));
186 
187   std::vector<DebugSubsectionRecordBuilder> Builders;
188   uint32_t Size = sizeof(uint32_t);
189   for (auto &SS : CVSS) {
190     DebugSubsectionRecordBuilder B(SS, CodeViewContainer::ObjectFile);
191     Size += B.calculateSerializedLength();
192     Builders.push_back(std::move(B));
193   }
194   uint8_t *Buffer = Allocator.Allocate<uint8_t>(Size);
195   MutableArrayRef<uint8_t> Output(Buffer, Size);
196   BinaryStreamWriter Writer(Output, support::little);
197 
198   Err(Writer.writeInteger<uint32_t>(COFF::DEBUG_SECTION_MAGIC));
199   for (const auto &B : Builders) {
200     Err(B.commit(Writer));
201   }
202   return {Output};
203 }
204 
205 // Take a CP and assign addresses and sizes to everything. Returns false if the
206 // layout is not valid to do.
207 static bool layoutCOFF(COFFParser &CP) {
208   // The section table starts immediately after the header, including the
209   // optional header.
210   CP.SectionTableStart =
211       CP.getHeaderSize() + CP.Obj.Header.SizeOfOptionalHeader;
212   if (CP.isPE())
213     CP.SectionTableStart += DOSStubSize + sizeof(COFF::PEMagic);
214   CP.SectionTableSize = COFF::SectionSize * CP.Obj.Sections.size();
215 
216   uint32_t CurrentSectionDataOffset =
217       CP.SectionTableStart + CP.SectionTableSize;
218 
219   for (COFFYAML::Section &S : CP.Obj.Sections) {
220     // We support specifying exactly one of SectionData or Subsections.  So if
221     // there is already some SectionData, then we don't need to do any of this.
222     if (S.Name == ".debug$S" && S.SectionData.binary_size() == 0) {
223       CodeViewYAML::initializeStringsAndChecksums(S.DebugS,
224                                                   CP.StringsAndChecksums);
225       if (CP.StringsAndChecksums.hasChecksums() &&
226           CP.StringsAndChecksums.hasStrings())
227         break;
228     }
229   }
230 
231   // Assign each section data address consecutively.
232   for (COFFYAML::Section &S : CP.Obj.Sections) {
233     if (S.Name == ".debug$S") {
234       if (S.SectionData.binary_size() == 0) {
235         assert(CP.StringsAndChecksums.hasStrings() &&
236                "Object file does not have debug string table!");
237 
238         S.SectionData =
239             toDebugS(S.DebugS, CP.StringsAndChecksums, CP.Allocator);
240       }
241     } else if (S.Name == ".debug$T") {
242       if (S.SectionData.binary_size() == 0)
243         S.SectionData = CodeViewYAML::toDebugT(S.DebugT, CP.Allocator, S.Name);
244     } else if (S.Name == ".debug$P") {
245       if (S.SectionData.binary_size() == 0)
246         S.SectionData = CodeViewYAML::toDebugT(S.DebugP, CP.Allocator, S.Name);
247     } else if (S.Name == ".debug$H") {
248       if (S.DebugH.hasValue() && S.SectionData.binary_size() == 0)
249         S.SectionData = CodeViewYAML::toDebugH(*S.DebugH, CP.Allocator);
250     }
251 
252     if (S.SectionData.binary_size() > 0) {
253       CurrentSectionDataOffset = alignTo(CurrentSectionDataOffset,
254                                          CP.isPE() ? CP.getFileAlignment() : 4);
255       S.Header.SizeOfRawData = S.SectionData.binary_size();
256       if (CP.isPE())
257         S.Header.SizeOfRawData =
258             alignTo(S.Header.SizeOfRawData, CP.getFileAlignment());
259       S.Header.PointerToRawData = CurrentSectionDataOffset;
260       CurrentSectionDataOffset += S.Header.SizeOfRawData;
261       if (!S.Relocations.empty()) {
262         S.Header.PointerToRelocations = CurrentSectionDataOffset;
263         S.Header.NumberOfRelocations = S.Relocations.size();
264         CurrentSectionDataOffset +=
265             S.Header.NumberOfRelocations * COFF::RelocationSize;
266       }
267     } else {
268       // Leave SizeOfRawData unaltered. For .bss sections in object files, it
269       // carries the section size.
270       S.Header.PointerToRawData = 0;
271     }
272   }
273 
274   uint32_t SymbolTableStart = CurrentSectionDataOffset;
275 
276   // Calculate number of symbols.
277   uint32_t NumberOfSymbols = 0;
278   for (std::vector<COFFYAML::Symbol>::iterator i = CP.Obj.Symbols.begin(),
279                                                e = CP.Obj.Symbols.end();
280        i != e; ++i) {
281     uint32_t NumberOfAuxSymbols = 0;
282     if (i->FunctionDefinition)
283       NumberOfAuxSymbols += 1;
284     if (i->bfAndefSymbol)
285       NumberOfAuxSymbols += 1;
286     if (i->WeakExternal)
287       NumberOfAuxSymbols += 1;
288     if (!i->File.empty())
289       NumberOfAuxSymbols +=
290           (i->File.size() + CP.getSymbolSize() - 1) / CP.getSymbolSize();
291     if (i->SectionDefinition)
292       NumberOfAuxSymbols += 1;
293     if (i->CLRToken)
294       NumberOfAuxSymbols += 1;
295     i->Header.NumberOfAuxSymbols = NumberOfAuxSymbols;
296     NumberOfSymbols += 1 + NumberOfAuxSymbols;
297   }
298 
299   // Store all the allocated start addresses in the header.
300   CP.Obj.Header.NumberOfSections = CP.Obj.Sections.size();
301   CP.Obj.Header.NumberOfSymbols = NumberOfSymbols;
302   if (NumberOfSymbols > 0 || CP.StringTable.size() > 4)
303     CP.Obj.Header.PointerToSymbolTable = SymbolTableStart;
304   else
305     CP.Obj.Header.PointerToSymbolTable = 0;
306 
307   *reinterpret_cast<support::ulittle32_t *>(&CP.StringTable[0]) =
308       CP.StringTable.size();
309 
310   return true;
311 }
312 
313 template <typename value_type> struct binary_le_impl {
314   value_type Value;
315   binary_le_impl(value_type V) : Value(V) {}
316 };
317 
318 template <typename value_type>
319 raw_ostream &operator<<(raw_ostream &OS,
320                         const binary_le_impl<value_type> &BLE) {
321   char Buffer[sizeof(BLE.Value)];
322   support::endian::write<value_type, support::little, support::unaligned>(
323       Buffer, BLE.Value);
324   OS.write(Buffer, sizeof(BLE.Value));
325   return OS;
326 }
327 
328 template <typename value_type>
329 binary_le_impl<value_type> binary_le(value_type V) {
330   return binary_le_impl<value_type>(V);
331 }
332 
333 template <size_t NumBytes> struct zeros_impl {};
334 
335 template <size_t NumBytes>
336 raw_ostream &operator<<(raw_ostream &OS, const zeros_impl<NumBytes> &) {
337   char Buffer[NumBytes];
338   memset(Buffer, 0, sizeof(Buffer));
339   OS.write(Buffer, sizeof(Buffer));
340   return OS;
341 }
342 
343 template <typename T> zeros_impl<sizeof(T)> zeros(const T &) {
344   return zeros_impl<sizeof(T)>();
345 }
346 
347 template <typename T>
348 static uint32_t initializeOptionalHeader(COFFParser &CP, uint16_t Magic,
349                                          T Header) {
350   memset(Header, 0, sizeof(*Header));
351   Header->Magic = Magic;
352   Header->SectionAlignment = CP.Obj.OptionalHeader->Header.SectionAlignment;
353   Header->FileAlignment = CP.Obj.OptionalHeader->Header.FileAlignment;
354   uint32_t SizeOfCode = 0, SizeOfInitializedData = 0,
355            SizeOfUninitializedData = 0;
356   uint32_t SizeOfHeaders = alignTo(CP.SectionTableStart + CP.SectionTableSize,
357                                    Header->FileAlignment);
358   uint32_t SizeOfImage = alignTo(SizeOfHeaders, Header->SectionAlignment);
359   uint32_t BaseOfData = 0;
360   for (const COFFYAML::Section &S : CP.Obj.Sections) {
361     if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_CODE)
362       SizeOfCode += S.Header.SizeOfRawData;
363     if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
364       SizeOfInitializedData += S.Header.SizeOfRawData;
365     if (S.Header.Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
366       SizeOfUninitializedData += S.Header.SizeOfRawData;
367     if (S.Name.equals(".text"))
368       Header->BaseOfCode = S.Header.VirtualAddress; // RVA
369     else if (S.Name.equals(".data"))
370       BaseOfData = S.Header.VirtualAddress; // RVA
371     if (S.Header.VirtualAddress)
372       SizeOfImage += alignTo(S.Header.VirtualSize, Header->SectionAlignment);
373   }
374   Header->SizeOfCode = SizeOfCode;
375   Header->SizeOfInitializedData = SizeOfInitializedData;
376   Header->SizeOfUninitializedData = SizeOfUninitializedData;
377   Header->AddressOfEntryPoint =
378       CP.Obj.OptionalHeader->Header.AddressOfEntryPoint; // RVA
379   Header->ImageBase = CP.Obj.OptionalHeader->Header.ImageBase;
380   Header->MajorOperatingSystemVersion =
381       CP.Obj.OptionalHeader->Header.MajorOperatingSystemVersion;
382   Header->MinorOperatingSystemVersion =
383       CP.Obj.OptionalHeader->Header.MinorOperatingSystemVersion;
384   Header->MajorImageVersion = CP.Obj.OptionalHeader->Header.MajorImageVersion;
385   Header->MinorImageVersion = CP.Obj.OptionalHeader->Header.MinorImageVersion;
386   Header->MajorSubsystemVersion =
387       CP.Obj.OptionalHeader->Header.MajorSubsystemVersion;
388   Header->MinorSubsystemVersion =
389       CP.Obj.OptionalHeader->Header.MinorSubsystemVersion;
390   Header->SizeOfImage = SizeOfImage;
391   Header->SizeOfHeaders = SizeOfHeaders;
392   Header->Subsystem = CP.Obj.OptionalHeader->Header.Subsystem;
393   Header->DLLCharacteristics = CP.Obj.OptionalHeader->Header.DLLCharacteristics;
394   Header->SizeOfStackReserve = CP.Obj.OptionalHeader->Header.SizeOfStackReserve;
395   Header->SizeOfStackCommit = CP.Obj.OptionalHeader->Header.SizeOfStackCommit;
396   Header->SizeOfHeapReserve = CP.Obj.OptionalHeader->Header.SizeOfHeapReserve;
397   Header->SizeOfHeapCommit = CP.Obj.OptionalHeader->Header.SizeOfHeapCommit;
398   Header->NumberOfRvaAndSize = COFF::NUM_DATA_DIRECTORIES + 1;
399   return BaseOfData;
400 }
401 
402 static bool writeCOFF(COFFParser &CP, raw_ostream &OS) {
403   if (CP.isPE()) {
404     // PE files start with a DOS stub.
405     object::dos_header DH;
406     memset(&DH, 0, sizeof(DH));
407 
408     // DOS EXEs start with "MZ" magic.
409     DH.Magic[0] = 'M';
410     DH.Magic[1] = 'Z';
411     // Initializing the AddressOfRelocationTable is strictly optional but
412     // mollifies certain tools which expect it to have a value greater than
413     // 0x40.
414     DH.AddressOfRelocationTable = sizeof(DH);
415     // This is the address of the PE signature.
416     DH.AddressOfNewExeHeader = DOSStubSize;
417 
418     // Write out our DOS stub.
419     OS.write(reinterpret_cast<char *>(&DH), sizeof(DH));
420     // Write padding until we reach the position of where our PE signature
421     // should live.
422     OS.write_zeros(DOSStubSize - sizeof(DH));
423     // Write out the PE signature.
424     OS.write(COFF::PEMagic, sizeof(COFF::PEMagic));
425   }
426   if (CP.useBigObj()) {
427     OS << binary_le(static_cast<uint16_t>(COFF::IMAGE_FILE_MACHINE_UNKNOWN))
428        << binary_le(static_cast<uint16_t>(0xffff))
429        << binary_le(
430               static_cast<uint16_t>(COFF::BigObjHeader::MinBigObjectVersion))
431        << binary_le(CP.Obj.Header.Machine)
432        << binary_le(CP.Obj.Header.TimeDateStamp);
433     OS.write(COFF::BigObjMagic, sizeof(COFF::BigObjMagic));
434     OS << zeros(uint32_t(0)) << zeros(uint32_t(0)) << zeros(uint32_t(0))
435        << zeros(uint32_t(0)) << binary_le(CP.Obj.Header.NumberOfSections)
436        << binary_le(CP.Obj.Header.PointerToSymbolTable)
437        << binary_le(CP.Obj.Header.NumberOfSymbols);
438   } else {
439     OS << binary_le(CP.Obj.Header.Machine)
440        << binary_le(static_cast<int16_t>(CP.Obj.Header.NumberOfSections))
441        << binary_le(CP.Obj.Header.TimeDateStamp)
442        << binary_le(CP.Obj.Header.PointerToSymbolTable)
443        << binary_le(CP.Obj.Header.NumberOfSymbols)
444        << binary_le(CP.Obj.Header.SizeOfOptionalHeader)
445        << binary_le(CP.Obj.Header.Characteristics);
446   }
447   if (CP.isPE()) {
448     if (CP.is64Bit()) {
449       object::pe32plus_header PEH;
450       initializeOptionalHeader(CP, COFF::PE32Header::PE32_PLUS, &PEH);
451       OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));
452     } else {
453       object::pe32_header PEH;
454       uint32_t BaseOfData =
455           initializeOptionalHeader(CP, COFF::PE32Header::PE32, &PEH);
456       PEH.BaseOfData = BaseOfData;
457       OS.write(reinterpret_cast<char *>(&PEH), sizeof(PEH));
458     }
459     for (const Optional<COFF::DataDirectory> &DD :
460          CP.Obj.OptionalHeader->DataDirectories) {
461       if (!DD.hasValue()) {
462         OS << zeros(uint32_t(0));
463         OS << zeros(uint32_t(0));
464       } else {
465         OS << binary_le(DD->RelativeVirtualAddress);
466         OS << binary_le(DD->Size);
467       }
468     }
469     OS << zeros(uint32_t(0));
470     OS << zeros(uint32_t(0));
471   }
472 
473   assert(OS.tell() == CP.SectionTableStart);
474   // Output section table.
475   for (std::vector<COFFYAML::Section>::iterator i = CP.Obj.Sections.begin(),
476                                                 e = CP.Obj.Sections.end();
477        i != e; ++i) {
478     OS.write(i->Header.Name, COFF::NameSize);
479     OS << binary_le(i->Header.VirtualSize)
480        << binary_le(i->Header.VirtualAddress)
481        << binary_le(i->Header.SizeOfRawData)
482        << binary_le(i->Header.PointerToRawData)
483        << binary_le(i->Header.PointerToRelocations)
484        << binary_le(i->Header.PointerToLineNumbers)
485        << binary_le(i->Header.NumberOfRelocations)
486        << binary_le(i->Header.NumberOfLineNumbers)
487        << binary_le(i->Header.Characteristics);
488   }
489   assert(OS.tell() == CP.SectionTableStart + CP.SectionTableSize);
490 
491   unsigned CurSymbol = 0;
492   StringMap<unsigned> SymbolTableIndexMap;
493   for (std::vector<COFFYAML::Symbol>::iterator I = CP.Obj.Symbols.begin(),
494                                                E = CP.Obj.Symbols.end();
495        I != E; ++I) {
496     SymbolTableIndexMap[I->Name] = CurSymbol;
497     CurSymbol += 1 + I->Header.NumberOfAuxSymbols;
498   }
499 
500   // Output section data.
501   for (const COFFYAML::Section &S : CP.Obj.Sections) {
502     if (S.Header.SizeOfRawData == 0 || S.Header.PointerToRawData == 0)
503       continue;
504     assert(S.Header.PointerToRawData >= OS.tell());
505     OS.write_zeros(S.Header.PointerToRawData - OS.tell());
506     S.SectionData.writeAsBinary(OS);
507     assert(S.Header.SizeOfRawData >= S.SectionData.binary_size());
508     OS.write_zeros(S.Header.SizeOfRawData - S.SectionData.binary_size());
509     for (const COFFYAML::Relocation &R : S.Relocations) {
510       uint32_t SymbolTableIndex;
511       if (R.SymbolTableIndex) {
512         if (!R.SymbolName.empty())
513           WithColor::error()
514               << "Both SymbolName and SymbolTableIndex specified\n";
515         SymbolTableIndex = *R.SymbolTableIndex;
516       } else {
517         SymbolTableIndex = SymbolTableIndexMap[R.SymbolName];
518       }
519       OS << binary_le(R.VirtualAddress) << binary_le(SymbolTableIndex)
520          << binary_le(R.Type);
521     }
522   }
523 
524   // Output symbol table.
525 
526   for (std::vector<COFFYAML::Symbol>::const_iterator i = CP.Obj.Symbols.begin(),
527                                                      e = CP.Obj.Symbols.end();
528        i != e; ++i) {
529     OS.write(i->Header.Name, COFF::NameSize);
530     OS << binary_le(i->Header.Value);
531     if (CP.useBigObj())
532       OS << binary_le(i->Header.SectionNumber);
533     else
534       OS << binary_le(static_cast<int16_t>(i->Header.SectionNumber));
535     OS << binary_le(i->Header.Type) << binary_le(i->Header.StorageClass)
536        << binary_le(i->Header.NumberOfAuxSymbols);
537 
538     if (i->FunctionDefinition) {
539       OS << binary_le(i->FunctionDefinition->TagIndex)
540          << binary_le(i->FunctionDefinition->TotalSize)
541          << binary_le(i->FunctionDefinition->PointerToLinenumber)
542          << binary_le(i->FunctionDefinition->PointerToNextFunction)
543          << zeros(i->FunctionDefinition->unused);
544       OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
545     }
546     if (i->bfAndefSymbol) {
547       OS << zeros(i->bfAndefSymbol->unused1)
548          << binary_le(i->bfAndefSymbol->Linenumber)
549          << zeros(i->bfAndefSymbol->unused2)
550          << binary_le(i->bfAndefSymbol->PointerToNextFunction)
551          << zeros(i->bfAndefSymbol->unused3);
552       OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
553     }
554     if (i->WeakExternal) {
555       OS << binary_le(i->WeakExternal->TagIndex)
556          << binary_le(i->WeakExternal->Characteristics)
557          << zeros(i->WeakExternal->unused);
558       OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
559     }
560     if (!i->File.empty()) {
561       unsigned SymbolSize = CP.getSymbolSize();
562       uint32_t NumberOfAuxRecords =
563           (i->File.size() + SymbolSize - 1) / SymbolSize;
564       uint32_t NumberOfAuxBytes = NumberOfAuxRecords * SymbolSize;
565       uint32_t NumZeros = NumberOfAuxBytes - i->File.size();
566       OS.write(i->File.data(), i->File.size());
567       OS.write_zeros(NumZeros);
568     }
569     if (i->SectionDefinition) {
570       OS << binary_le(i->SectionDefinition->Length)
571          << binary_le(i->SectionDefinition->NumberOfRelocations)
572          << binary_le(i->SectionDefinition->NumberOfLinenumbers)
573          << binary_le(i->SectionDefinition->CheckSum)
574          << binary_le(static_cast<int16_t>(i->SectionDefinition->Number))
575          << binary_le(i->SectionDefinition->Selection)
576          << zeros(i->SectionDefinition->unused)
577          << binary_le(static_cast<int16_t>(i->SectionDefinition->Number >> 16));
578       OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
579     }
580     if (i->CLRToken) {
581       OS << binary_le(i->CLRToken->AuxType) << zeros(i->CLRToken->unused1)
582          << binary_le(i->CLRToken->SymbolTableIndex)
583          << zeros(i->CLRToken->unused2);
584       OS.write_zeros(CP.getSymbolSize() - COFF::Symbol16Size);
585     }
586   }
587 
588   // Output string table.
589   if (CP.Obj.Header.PointerToSymbolTable)
590     OS.write(&CP.StringTable[0], CP.StringTable.size());
591   return true;
592 }
593 
594 namespace llvm {
595 namespace yaml {
596 
597 bool yaml2coff(llvm::COFFYAML::Object &Doc, raw_ostream &Out,
598                ErrorHandler ErrHandler) {
599   COFFParser CP(Doc, ErrHandler);
600   if (!CP.parse()) {
601     ErrHandler("failed to parse YAML file");
602     return false;
603   }
604 
605   if (!layoutOptionalHeader(CP)) {
606     ErrHandler("failed to layout optional header for COFF file");
607     return false;
608   }
609 
610   if (!layoutCOFF(CP)) {
611     ErrHandler("failed to layout COFF file");
612     return false;
613   }
614   if (!writeCOFF(CP, Out)) {
615     ErrHandler("failed to write COFF file");
616     return false;
617   }
618   return true;
619 }
620 
621 } // namespace yaml
622 } // namespace llvm
623