LLVM  9.0.0svn
WinCOFFObjectWriter.cpp
Go to the documentation of this file.
1 //===- llvm/MC/WinCOFFObjectWriter.cpp ------------------------------------===//
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 // This file contains an implementation of a Win32 COFF object file writer.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/ADT/DenseMap.h"
14 #include "llvm/ADT/STLExtras.h"
15 #include "llvm/ADT/SmallString.h"
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/ADT/Twine.h"
19 #include "llvm/BinaryFormat/COFF.h"
20 #include "llvm/MC/MCAsmLayout.h"
21 #include "llvm/MC/MCAssembler.h"
22 #include "llvm/MC/MCContext.h"
23 #include "llvm/MC/MCExpr.h"
24 #include "llvm/MC/MCFixup.h"
25 #include "llvm/MC/MCFragment.h"
26 #include "llvm/MC/MCObjectWriter.h"
27 #include "llvm/MC/MCSection.h"
28 #include "llvm/MC/MCSectionCOFF.h"
29 #include "llvm/MC/MCSymbol.h"
30 #include "llvm/MC/MCSymbolCOFF.h"
31 #include "llvm/MC/MCValue.h"
34 #include "llvm/Support/Casting.h"
35 #include "llvm/Support/Endian.h"
37 #include "llvm/Support/JamCRC.h"
38 #include "llvm/Support/LEB128.h"
41 #include <algorithm>
42 #include <cassert>
43 #include <cstddef>
44 #include <cstdint>
45 #include <cstring>
46 #include <ctime>
47 #include <memory>
48 #include <string>
49 #include <vector>
50 
51 using namespace llvm;
53 
54 #define DEBUG_TYPE "WinCOFFObjectWriter"
55 
56 namespace {
57 
59 
61  ATWeakExternal,
62  ATFile,
63  ATSectionDefinition
64 };
65 
66 struct AuxSymbol {
68  COFF::Auxiliary Aux;
69 };
70 
71 class COFFSection;
72 
73 class COFFSymbol {
74 public:
75  COFF::symbol Data = {};
76 
77  using AuxiliarySymbols = SmallVector<AuxSymbol, 1>;
78 
79  name Name;
80  int Index;
81  AuxiliarySymbols Aux;
82  COFFSymbol *Other = nullptr;
83  COFFSection *Section = nullptr;
84  int Relocations = 0;
85  const MCSymbol *MC = nullptr;
86 
87  COFFSymbol(StringRef Name) : Name(Name) {}
88 
89  void set_name_offset(uint32_t Offset);
90 
91  int64_t getIndex() const { return Index; }
92  void setIndex(int Value) {
93  Index = Value;
94  if (MC)
95  MC->setIndex(static_cast<uint32_t>(Value));
96  }
97 };
98 
99 // This class contains staging data for a COFF relocation entry.
100 struct COFFRelocation {
102  COFFSymbol *Symb = nullptr;
103 
104  COFFRelocation() = default;
105 
106  static size_t size() { return COFF::RelocationSize; }
107 };
108 
109 using relocations = std::vector<COFFRelocation>;
110 
111 class COFFSection {
112 public:
113  COFF::section Header = {};
114 
115  std::string Name;
116  int Number;
117  MCSectionCOFF const *MCSection = nullptr;
118  COFFSymbol *Symbol = nullptr;
119  relocations Relocations;
120 
121  COFFSection(StringRef Name) : Name(Name) {}
122 };
123 
124 class WinCOFFObjectWriter : public MCObjectWriter {
125 public:
127 
128  using symbols = std::vector<std::unique_ptr<COFFSymbol>>;
129  using sections = std::vector<std::unique_ptr<COFFSection>>;
130 
131  using symbol_map = DenseMap<MCSymbol const *, COFFSymbol *>;
132  using section_map = DenseMap<MCSection const *, COFFSection *>;
133 
134  std::unique_ptr<MCWinCOFFObjectTargetWriter> TargetObjectWriter;
135 
136  // Root level file contents.
137  COFF::header Header = {};
138  sections Sections;
139  symbols Symbols;
141 
142  // Maps used during object file creation.
143  section_map SectionMap;
144  symbol_map SymbolMap;
145 
146  bool UseBigObj;
147 
148  bool EmitAddrsigSection = false;
149  MCSectionCOFF *AddrsigSection;
150  std::vector<const MCSymbol *> AddrsigSyms;
151 
152  WinCOFFObjectWriter(std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW,
153  raw_pwrite_stream &OS);
154 
155  void reset() override {
156  memset(&Header, 0, sizeof(Header));
157  Header.Machine = TargetObjectWriter->getMachine();
158  Sections.clear();
159  Symbols.clear();
160  Strings.clear();
161  SectionMap.clear();
162  SymbolMap.clear();
164  }
165 
166  COFFSymbol *createSymbol(StringRef Name);
167  COFFSymbol *GetOrCreateCOFFSymbol(const MCSymbol *Symbol);
168  COFFSection *createSection(StringRef Name);
169 
170  void defineSection(MCSectionCOFF const &Sec);
171 
172  COFFSymbol *getLinkedSymbol(const MCSymbol &Symbol);
173  void DefineSymbol(const MCSymbol &Symbol, MCAssembler &Assembler,
174  const MCAsmLayout &Layout);
175 
176  void SetSymbolName(COFFSymbol &S);
177  void SetSectionName(COFFSection &S);
178 
179  bool IsPhysicalSection(COFFSection *S);
180 
181  // Entity writing methods.
182 
183  void WriteFileHeader(const COFF::header &Header);
184  void WriteSymbol(const COFFSymbol &S);
185  void WriteAuxiliarySymbols(const COFFSymbol::AuxiliarySymbols &S);
186  void writeSectionHeaders();
187  void WriteRelocation(const COFF::relocation &R);
188  uint32_t writeSectionContents(MCAssembler &Asm, const MCAsmLayout &Layout,
189  const MCSection &MCSec);
190  void writeSection(MCAssembler &Asm, const MCAsmLayout &Layout,
191  const COFFSection &Sec, const MCSection &MCSec);
192 
193  // MCObjectWriter interface implementation.
194 
195  void executePostLayoutBinding(MCAssembler &Asm,
196  const MCAsmLayout &Layout) override;
197 
198  bool isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
199  const MCSymbol &SymA,
200  const MCFragment &FB, bool InSet,
201  bool IsPCRel) const override;
202 
203  void recordRelocation(MCAssembler &Asm, const MCAsmLayout &Layout,
204  const MCFragment *Fragment, const MCFixup &Fixup,
205  MCValue Target, uint64_t &FixedValue) override;
206 
207  void createFileSymbols(MCAssembler &Asm);
208  void assignSectionNumbers();
209  void assignFileOffsets(MCAssembler &Asm, const MCAsmLayout &Layout);
210 
211  void emitAddrsigSection() override { EmitAddrsigSection = true; }
212  void addAddrsigSymbol(const MCSymbol *Sym) override {
213  AddrsigSyms.push_back(Sym);
214  }
215 
216  uint64_t writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
217 };
218 
219 } // end anonymous namespace
220 
221 //------------------------------------------------------------------------------
222 // Symbol class implementation
223 
224 // In the case that the name does not fit within 8 bytes, the offset
225 // into the string table is stored in the last 4 bytes instead, leaving
226 // the first 4 bytes as 0.
227 void COFFSymbol::set_name_offset(uint32_t Offset) {
228  write32le(Data.Name + 0, 0);
229  write32le(Data.Name + 4, Offset);
230 }
231 
232 //------------------------------------------------------------------------------
233 // WinCOFFObjectWriter class implementation
234 
235 WinCOFFObjectWriter::WinCOFFObjectWriter(
236  std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS)
237  : W(OS, support::little), TargetObjectWriter(std::move(MOTW)) {
238  Header.Machine = TargetObjectWriter->getMachine();
239 }
240 
241 COFFSymbol *WinCOFFObjectWriter::createSymbol(StringRef Name) {
242  Symbols.push_back(make_unique<COFFSymbol>(Name));
243  return Symbols.back().get();
244 }
245 
246 COFFSymbol *WinCOFFObjectWriter::GetOrCreateCOFFSymbol(const MCSymbol *Symbol) {
247  COFFSymbol *&Ret = SymbolMap[Symbol];
248  if (!Ret)
249  Ret = createSymbol(Symbol->getName());
250  return Ret;
251 }
252 
253 COFFSection *WinCOFFObjectWriter::createSection(StringRef Name) {
254  Sections.emplace_back(make_unique<COFFSection>(Name));
255  return Sections.back().get();
256 }
257 
258 static uint32_t getAlignment(const MCSectionCOFF &Sec) {
259  switch (Sec.getAlignment()) {
260  case 1:
262  case 2:
264  case 4:
266  case 8:
268  case 16:
270  case 32:
272  case 64:
274  case 128:
276  case 256:
278  case 512:
280  case 1024:
282  case 2048:
284  case 4096:
286  case 8192:
288  }
289  llvm_unreachable("unsupported section alignment");
290 }
291 
292 /// This function takes a section data object from the assembler
293 /// and creates the associated COFF section staging object.
294 void WinCOFFObjectWriter::defineSection(const MCSectionCOFF &MCSec) {
295  COFFSection *Section = createSection(MCSec.getSectionName());
296  COFFSymbol *Symbol = createSymbol(MCSec.getSectionName());
297  Section->Symbol = Symbol;
298  Symbol->Section = Section;
299  Symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_STATIC;
300 
301  // Create a COMDAT symbol if needed.
303  if (const MCSymbol *S = MCSec.getCOMDATSymbol()) {
304  COFFSymbol *COMDATSymbol = GetOrCreateCOFFSymbol(S);
305  if (COMDATSymbol->Section)
306  report_fatal_error("two sections have the same comdat");
307  COMDATSymbol->Section = Section;
308  }
309  }
310 
311  // In this case the auxiliary symbol is a Section Definition.
312  Symbol->Aux.resize(1);
313  Symbol->Aux[0] = {};
314  Symbol->Aux[0].AuxType = ATSectionDefinition;
315  Symbol->Aux[0].Aux.SectionDefinition.Selection = MCSec.getSelection();
316 
317  // Set section alignment.
318  Section->Header.Characteristics = MCSec.getCharacteristics();
319  Section->Header.Characteristics |= getAlignment(MCSec);
320 
321  // Bind internal COFF section to MC section.
322  Section->MCSection = &MCSec;
323  SectionMap[&MCSec] = Section;
324 }
325 
326 static uint64_t getSymbolValue(const MCSymbol &Symbol,
327  const MCAsmLayout &Layout) {
328  if (Symbol.isCommon() && Symbol.isExternal())
329  return Symbol.getCommonSize();
330 
331  uint64_t Res;
332  if (!Layout.getSymbolOffset(Symbol, Res))
333  return 0;
334 
335  return Res;
336 }
337 
338 COFFSymbol *WinCOFFObjectWriter::getLinkedSymbol(const MCSymbol &Symbol) {
339  if (!Symbol.isVariable())
340  return nullptr;
341 
342  const MCSymbolRefExpr *SymRef =
344  if (!SymRef)
345  return nullptr;
346 
347  const MCSymbol &Aliasee = SymRef->getSymbol();
348  if (!Aliasee.isUndefined())
349  return nullptr;
350  return GetOrCreateCOFFSymbol(&Aliasee);
351 }
352 
353 /// This function takes a symbol data object from the assembler
354 /// and creates the associated COFF symbol staging object.
355 void WinCOFFObjectWriter::DefineSymbol(const MCSymbol &MCSym,
356  MCAssembler &Assembler,
357  const MCAsmLayout &Layout) {
358  COFFSymbol *Sym = GetOrCreateCOFFSymbol(&MCSym);
359  const MCSymbol *Base = Layout.getBaseSymbol(MCSym);
360  COFFSection *Sec = nullptr;
361  if (Base && Base->getFragment()) {
362  Sec = SectionMap[Base->getFragment()->getParent()];
363  if (Sym->Section && Sym->Section != Sec)
364  report_fatal_error("conflicting sections for symbol");
365  }
366 
367  COFFSymbol *Local = nullptr;
368  if (cast<MCSymbolCOFF>(MCSym).isWeakExternal()) {
369  Sym->Data.StorageClass = COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL;
370 
371  COFFSymbol *WeakDefault = getLinkedSymbol(MCSym);
372  if (!WeakDefault) {
373  std::string WeakName = (".weak." + MCSym.getName() + ".default").str();
374  WeakDefault = createSymbol(WeakName);
375  if (!Sec)
376  WeakDefault->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE;
377  else
378  WeakDefault->Section = Sec;
379  Local = WeakDefault;
380  }
381 
382  Sym->Other = WeakDefault;
383 
384  // Setup the Weak External auxiliary symbol.
385  Sym->Aux.resize(1);
386  memset(&Sym->Aux[0], 0, sizeof(Sym->Aux[0]));
387  Sym->Aux[0].AuxType = ATWeakExternal;
388  Sym->Aux[0].Aux.WeakExternal.TagIndex = 0;
389  Sym->Aux[0].Aux.WeakExternal.Characteristics =
391  } else {
392  if (!Base)
393  Sym->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE;
394  else
395  Sym->Section = Sec;
396  Local = Sym;
397  }
398 
399  if (Local) {
400  Local->Data.Value = getSymbolValue(MCSym, Layout);
401 
402  const MCSymbolCOFF &SymbolCOFF = cast<MCSymbolCOFF>(MCSym);
403  Local->Data.Type = SymbolCOFF.getType();
404  Local->Data.StorageClass = SymbolCOFF.getClass();
405 
406  // If no storage class was specified in the streamer, define it here.
407  if (Local->Data.StorageClass == COFF::IMAGE_SYM_CLASS_NULL) {
408  bool IsExternal = MCSym.isExternal() ||
409  (!MCSym.getFragment() && !MCSym.isVariable());
410 
411  Local->Data.StorageClass = IsExternal ? COFF::IMAGE_SYM_CLASS_EXTERNAL
413  }
414  }
415 
416  Sym->MC = &MCSym;
417 }
418 
419 // Maximum offsets for different string table entry encodings.
420 enum : unsigned { Max7DecimalOffset = 9999999U };
421 enum : uint64_t { MaxBase64Offset = 0xFFFFFFFFFULL }; // 64^6, including 0
422 
423 // Encode a string table entry offset in base 64, padded to 6 chars, and
424 // prefixed with a double slash: '//AAAAAA', '//AAAAAB', ...
425 // Buffer must be at least 8 bytes large. No terminating null appended.
426 static void encodeBase64StringEntry(char *Buffer, uint64_t Value) {
427  assert(Value > Max7DecimalOffset && Value <= MaxBase64Offset &&
428  "Illegal section name encoding for value");
429 
430  static const char Alphabet[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
431  "abcdefghijklmnopqrstuvwxyz"
432  "0123456789+/";
433 
434  Buffer[0] = '/';
435  Buffer[1] = '/';
436 
437  char *Ptr = Buffer + 7;
438  for (unsigned i = 0; i < 6; ++i) {
439  unsigned Rem = Value % 64;
440  Value /= 64;
441  *(Ptr--) = Alphabet[Rem];
442  }
443 }
444 
445 void WinCOFFObjectWriter::SetSectionName(COFFSection &S) {
446  if (S.Name.size() <= COFF::NameSize) {
447  std::memcpy(S.Header.Name, S.Name.c_str(), S.Name.size());
448  return;
449  }
450 
451  uint64_t StringTableEntry = Strings.getOffset(S.Name);
452  if (StringTableEntry <= Max7DecimalOffset) {
454  Twine('/').concat(Twine(StringTableEntry)).toVector(Buffer);
455  assert(Buffer.size() <= COFF::NameSize && Buffer.size() >= 2);
456  std::memcpy(S.Header.Name, Buffer.data(), Buffer.size());
457  return;
458  }
459  if (StringTableEntry <= MaxBase64Offset) {
460  // Starting with 10,000,000, offsets are encoded as base64.
461  encodeBase64StringEntry(S.Header.Name, StringTableEntry);
462  return;
463  }
464  report_fatal_error("COFF string table is greater than 64 GB.");
465 }
466 
467 void WinCOFFObjectWriter::SetSymbolName(COFFSymbol &S) {
468  if (S.Name.size() > COFF::NameSize)
469  S.set_name_offset(Strings.getOffset(S.Name));
470  else
471  std::memcpy(S.Data.Name, S.Name.c_str(), S.Name.size());
472 }
473 
474 bool WinCOFFObjectWriter::IsPhysicalSection(COFFSection *S) {
475  return (S->Header.Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA) ==
476  0;
477 }
478 
479 //------------------------------------------------------------------------------
480 // entity writing methods
481 
482 void WinCOFFObjectWriter::WriteFileHeader(const COFF::header &Header) {
483  if (UseBigObj) {
484  W.write<uint16_t>(COFF::IMAGE_FILE_MACHINE_UNKNOWN);
485  W.write<uint16_t>(0xFFFF);
487  W.write<uint16_t>(Header.Machine);
488  W.write<uint32_t>(Header.TimeDateStamp);
489  W.OS.write(COFF::BigObjMagic, sizeof(COFF::BigObjMagic));
490  W.write<uint32_t>(0);
491  W.write<uint32_t>(0);
492  W.write<uint32_t>(0);
493  W.write<uint32_t>(0);
494  W.write<uint32_t>(Header.NumberOfSections);
495  W.write<uint32_t>(Header.PointerToSymbolTable);
496  W.write<uint32_t>(Header.NumberOfSymbols);
497  } else {
498  W.write<uint16_t>(Header.Machine);
499  W.write<uint16_t>(static_cast<int16_t>(Header.NumberOfSections));
500  W.write<uint32_t>(Header.TimeDateStamp);
501  W.write<uint32_t>(Header.PointerToSymbolTable);
502  W.write<uint32_t>(Header.NumberOfSymbols);
503  W.write<uint16_t>(Header.SizeOfOptionalHeader);
504  W.write<uint16_t>(Header.Characteristics);
505  }
506 }
507 
508 void WinCOFFObjectWriter::WriteSymbol(const COFFSymbol &S) {
509  W.OS.write(S.Data.Name, COFF::NameSize);
510  W.write<uint32_t>(S.Data.Value);
511  if (UseBigObj)
512  W.write<uint32_t>(S.Data.SectionNumber);
513  else
514  W.write<uint16_t>(static_cast<int16_t>(S.Data.SectionNumber));
515  W.write<uint16_t>(S.Data.Type);
516  W.OS << char(S.Data.StorageClass);
517  W.OS << char(S.Data.NumberOfAuxSymbols);
518  WriteAuxiliarySymbols(S.Aux);
519 }
520 
521 void WinCOFFObjectWriter::WriteAuxiliarySymbols(
522  const COFFSymbol::AuxiliarySymbols &S) {
523  for (const AuxSymbol &i : S) {
524  switch (i.AuxType) {
525  case ATWeakExternal:
526  W.write<uint32_t>(i.Aux.WeakExternal.TagIndex);
527  W.write<uint32_t>(i.Aux.WeakExternal.Characteristics);
528  W.OS.write_zeros(sizeof(i.Aux.WeakExternal.unused));
529  if (UseBigObj)
530  W.OS.write_zeros(COFF::Symbol32Size - COFF::Symbol16Size);
531  break;
532  case ATFile:
533  W.OS.write(reinterpret_cast<const char *>(&i.Aux),
534  UseBigObj ? COFF::Symbol32Size : COFF::Symbol16Size);
535  break;
536  case ATSectionDefinition:
537  W.write<uint32_t>(i.Aux.SectionDefinition.Length);
538  W.write<uint16_t>(i.Aux.SectionDefinition.NumberOfRelocations);
539  W.write<uint16_t>(i.Aux.SectionDefinition.NumberOfLinenumbers);
540  W.write<uint32_t>(i.Aux.SectionDefinition.CheckSum);
541  W.write<uint16_t>(static_cast<int16_t>(i.Aux.SectionDefinition.Number));
542  W.OS << char(i.Aux.SectionDefinition.Selection);
543  W.OS.write_zeros(sizeof(i.Aux.SectionDefinition.unused));
544  W.write<uint16_t>(static_cast<int16_t>(i.Aux.SectionDefinition.Number >> 16));
545  if (UseBigObj)
546  W.OS.write_zeros(COFF::Symbol32Size - COFF::Symbol16Size);
547  break;
548  }
549  }
550 }
551 
552 // Write the section header.
553 void WinCOFFObjectWriter::writeSectionHeaders() {
554  // Section numbers must be monotonically increasing in the section
555  // header, but our Sections array is not sorted by section number,
556  // so make a copy of Sections and sort it.
557  std::vector<COFFSection *> Arr;
558  for (auto &Section : Sections)
559  Arr.push_back(Section.get());
560  llvm::sort(Arr, [](const COFFSection *A, const COFFSection *B) {
561  return A->Number < B->Number;
562  });
563 
564  for (auto &Section : Arr) {
565  if (Section->Number == -1)
566  continue;
567 
568  COFF::section &S = Section->Header;
569  if (Section->Relocations.size() >= 0xffff)
571  W.OS.write(S.Name, COFF::NameSize);
572  W.write<uint32_t>(S.VirtualSize);
573  W.write<uint32_t>(S.VirtualAddress);
574  W.write<uint32_t>(S.SizeOfRawData);
575  W.write<uint32_t>(S.PointerToRawData);
576  W.write<uint32_t>(S.PointerToRelocations);
577  W.write<uint32_t>(S.PointerToLineNumbers);
578  W.write<uint16_t>(S.NumberOfRelocations);
579  W.write<uint16_t>(S.NumberOfLineNumbers);
580  W.write<uint32_t>(S.Characteristics);
581  }
582 }
583 
584 void WinCOFFObjectWriter::WriteRelocation(const COFF::relocation &R) {
585  W.write<uint32_t>(R.VirtualAddress);
586  W.write<uint32_t>(R.SymbolTableIndex);
587  W.write<uint16_t>(R.Type);
588 }
589 
590 // Write MCSec's contents. What this function does is essentially
591 // "Asm.writeSectionData(&MCSec, Layout)", but it's a bit complicated
592 // because it needs to compute a CRC.
593 uint32_t WinCOFFObjectWriter::writeSectionContents(MCAssembler &Asm,
594  const MCAsmLayout &Layout,
595  const MCSection &MCSec) {
596  // Save the contents of the section to a temporary buffer, we need this
597  // to CRC the data before we dump it into the object file.
599  raw_svector_ostream VecOS(Buf);
600  Asm.writeSectionData(VecOS, &MCSec, Layout);
601 
602  // Write the section contents to the object file.
603  W.OS << Buf;
604 
605  // Calculate our CRC with an initial value of '0', this is not how
606  // JamCRC is specified but it aligns with the expected output.
607  JamCRC JC(/*Init=*/0);
608  JC.update(Buf);
609  return JC.getCRC();
610 }
611 
612 void WinCOFFObjectWriter::writeSection(MCAssembler &Asm,
613  const MCAsmLayout &Layout,
614  const COFFSection &Sec,
615  const MCSection &MCSec) {
616  if (Sec.Number == -1)
617  return;
618 
619  // Write the section contents.
620  if (Sec.Header.PointerToRawData != 0) {
621  assert(W.OS.tell() == Sec.Header.PointerToRawData &&
622  "Section::PointerToRawData is insane!");
623 
624  uint32_t CRC = writeSectionContents(Asm, Layout, MCSec);
625 
626  // Update the section definition auxiliary symbol to record the CRC.
627  COFFSection *Sec = SectionMap[&MCSec];
628  COFFSymbol::AuxiliarySymbols &AuxSyms = Sec->Symbol->Aux;
629  assert(AuxSyms.size() == 1 && AuxSyms[0].AuxType == ATSectionDefinition);
630  AuxSymbol &SecDef = AuxSyms[0];
631  SecDef.Aux.SectionDefinition.CheckSum = CRC;
632  }
633 
634  // Write relocations for this section.
635  if (Sec.Relocations.empty()) {
636  assert(Sec.Header.PointerToRelocations == 0 &&
637  "Section::PointerToRelocations is insane!");
638  return;
639  }
640 
641  assert(W.OS.tell() == Sec.Header.PointerToRelocations &&
642  "Section::PointerToRelocations is insane!");
643 
644  if (Sec.Relocations.size() >= 0xffff) {
645  // In case of overflow, write actual relocation count as first
646  // relocation. Including the synthetic reloc itself (+ 1).
648  R.VirtualAddress = Sec.Relocations.size() + 1;
649  R.SymbolTableIndex = 0;
650  R.Type = 0;
651  WriteRelocation(R);
652  }
653 
654  for (const auto &Relocation : Sec.Relocations)
655  WriteRelocation(Relocation.Data);
656 }
657 
658 ////////////////////////////////////////////////////////////////////////////////
659 // MCObjectWriter interface implementations
660 
661 void WinCOFFObjectWriter::executePostLayoutBinding(MCAssembler &Asm,
662  const MCAsmLayout &Layout) {
663  if (EmitAddrsigSection) {
664  AddrsigSection = Asm.getContext().getCOFFSection(
665  ".llvm_addrsig", COFF::IMAGE_SCN_LNK_REMOVE,
667  Asm.registerSection(*AddrsigSection);
668  }
669 
670  // "Define" each section & symbol. This creates section & symbol
671  // entries in the staging area.
672  for (const auto &Section : Asm)
673  defineSection(static_cast<const MCSectionCOFF &>(Section));
674 
675  for (const MCSymbol &Symbol : Asm.symbols())
676  if (!Symbol.isTemporary())
677  DefineSymbol(Symbol, Asm, Layout);
678 }
679 
680 bool WinCOFFObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(
681  const MCAssembler &Asm, const MCSymbol &SymA, const MCFragment &FB,
682  bool InSet, bool IsPCRel) const {
683  // Don't drop relocations between functions, even if they are in the same text
684  // section. Multiple Visual C++ linker features depend on having the
685  // relocations present. The /INCREMENTAL flag will cause these relocations to
686  // point to thunks, and the /GUARD:CF flag assumes that it can use relocations
687  // to approximate the set of all address taken functions. LLD's implementation
688  // of /GUARD:CF also relies on the existance of these relocations.
689  uint16_t Type = cast<MCSymbolCOFF>(SymA).getType();
691  return false;
693  InSet, IsPCRel);
694 }
695 
696 void WinCOFFObjectWriter::recordRelocation(MCAssembler &Asm,
697  const MCAsmLayout &Layout,
698  const MCFragment *Fragment,
699  const MCFixup &Fixup, MCValue Target,
700  uint64_t &FixedValue) {
701  assert(Target.getSymA() && "Relocation must reference a symbol!");
702 
703  const MCSymbol &A = Target.getSymA()->getSymbol();
704  if (!A.isRegistered()) {
705  Asm.getContext().reportError(Fixup.getLoc(),
706  Twine("symbol '") + A.getName() +
707  "' can not be undefined");
708  return;
709  }
710  if (A.isTemporary() && A.isUndefined()) {
711  Asm.getContext().reportError(Fixup.getLoc(),
712  Twine("assembler label '") + A.getName() +
713  "' can not be undefined");
714  return;
715  }
716 
717  MCSection *MCSec = Fragment->getParent();
718 
719  // Mark this symbol as requiring an entry in the symbol table.
720  assert(SectionMap.find(MCSec) != SectionMap.end() &&
721  "Section must already have been defined in executePostLayoutBinding!");
722 
723  COFFSection *Sec = SectionMap[MCSec];
724  const MCSymbolRefExpr *SymB = Target.getSymB();
725 
726  if (SymB) {
727  const MCSymbol *B = &SymB->getSymbol();
728  if (!B->getFragment()) {
729  Asm.getContext().reportError(
730  Fixup.getLoc(),
731  Twine("symbol '") + B->getName() +
732  "' can not be undefined in a subtraction expression");
733  return;
734  }
735 
736  // Offset of the symbol in the section
737  int64_t OffsetOfB = Layout.getSymbolOffset(*B);
738 
739  // Offset of the relocation in the section
740  int64_t OffsetOfRelocation =
741  Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
742 
743  FixedValue = (OffsetOfRelocation - OffsetOfB) + Target.getConstant();
744  } else {
745  FixedValue = Target.getConstant();
746  }
747 
748  COFFRelocation Reloc;
749 
750  Reloc.Data.SymbolTableIndex = 0;
751  Reloc.Data.VirtualAddress = Layout.getFragmentOffset(Fragment);
752 
753  // Turn relocations for temporary symbols into section relocations.
754  if (A.isTemporary()) {
755  MCSection *TargetSection = &A.getSection();
756  assert(
757  SectionMap.find(TargetSection) != SectionMap.end() &&
758  "Section must already have been defined in executePostLayoutBinding!");
759  Reloc.Symb = SectionMap[TargetSection]->Symbol;
760  FixedValue += Layout.getSymbolOffset(A);
761  } else {
762  assert(
763  SymbolMap.find(&A) != SymbolMap.end() &&
764  "Symbol must already have been defined in executePostLayoutBinding!");
765  Reloc.Symb = SymbolMap[&A];
766  }
767 
768  ++Reloc.Symb->Relocations;
769 
770  Reloc.Data.VirtualAddress += Fixup.getOffset();
771  Reloc.Data.Type = TargetObjectWriter->getRelocType(
772  Asm.getContext(), Target, Fixup, SymB, Asm.getBackend());
773 
774  // FIXME: Can anyone explain what this does other than adjust for the size
775  // of the offset?
776  if ((Header.Machine == COFF::IMAGE_FILE_MACHINE_AMD64 &&
777  Reloc.Data.Type == COFF::IMAGE_REL_AMD64_REL32) ||
779  Reloc.Data.Type == COFF::IMAGE_REL_I386_REL32))
780  FixedValue += 4;
781 
782  if (Header.Machine == COFF::IMAGE_FILE_MACHINE_ARMNT) {
783  switch (Reloc.Data.Type) {
790  break;
793  // IMAGE_REL_ARM_BRANCH11 and IMAGE_REL_ARM_BLX11 are only used for
794  // pre-ARMv7, which implicitly rules it out of ARMNT (it would be valid
795  // for Windows CE).
799  // IMAGE_REL_ARM_BRANCH24, IMAGE_REL_ARM_BLX24, IMAGE_REL_ARM_MOV32A are
800  // only used for ARM mode code, which is documented as being unsupported
801  // by Windows on ARM. Empirical proof indicates that masm is able to
802  // generate the relocations however the rest of the MSVC toolchain is
803  // unable to handle it.
804  llvm_unreachable("unsupported relocation");
805  break;
807  break;
811  // IMAGE_REL_BRANCH20T, IMAGE_REL_ARM_BRANCH24T, IMAGE_REL_ARM_BLX23T all
812  // perform a 4 byte adjustment to the relocation. Relative branches are
813  // offset by 4 on ARM, however, because there is no RELA relocations, all
814  // branches are offset by 4.
815  FixedValue = FixedValue + 4;
816  break;
817  }
818  }
819 
820  // The fixed value never makes sense for section indices, ignore it.
821  if (Fixup.getKind() == FK_SecRel_2)
822  FixedValue = 0;
823 
824  if (TargetObjectWriter->recordRelocation(Fixup))
825  Sec->Relocations.push_back(Reloc);
826 }
827 
828 static std::time_t getTime() {
829  std::time_t Now = time(nullptr);
830  if (Now < 0 || !isUInt<32>(Now))
831  return UINT32_MAX;
832  return Now;
833 }
834 
835 // Create .file symbols.
836 void WinCOFFObjectWriter::createFileSymbols(MCAssembler &Asm) {
837  for (const std::string &Name : Asm.getFileNames()) {
838  // round up to calculate the number of auxiliary symbols required
839  unsigned SymbolSize = UseBigObj ? COFF::Symbol32Size : COFF::Symbol16Size;
840  unsigned Count = (Name.size() + SymbolSize - 1) / SymbolSize;
841 
842  COFFSymbol *File = createSymbol(".file");
843  File->Data.SectionNumber = COFF::IMAGE_SYM_DEBUG;
844  File->Data.StorageClass = COFF::IMAGE_SYM_CLASS_FILE;
845  File->Aux.resize(Count);
846 
847  unsigned Offset = 0;
848  unsigned Length = Name.size();
849  for (auto &Aux : File->Aux) {
850  Aux.AuxType = ATFile;
851 
852  if (Length > SymbolSize) {
853  memcpy(&Aux.Aux, Name.c_str() + Offset, SymbolSize);
854  Length = Length - SymbolSize;
855  } else {
856  memcpy(&Aux.Aux, Name.c_str() + Offset, Length);
857  memset((char *)&Aux.Aux + Length, 0, SymbolSize - Length);
858  break;
859  }
860 
861  Offset += SymbolSize;
862  }
863  }
864 }
865 
866 static bool isAssociative(const COFFSection &Section) {
867  return Section.Symbol->Aux[0].Aux.SectionDefinition.Selection ==
869 }
870 
871 void WinCOFFObjectWriter::assignSectionNumbers() {
872  size_t I = 1;
873  auto Assign = [&](COFFSection &Section) {
874  Section.Number = I;
875  Section.Symbol->Data.SectionNumber = I;
876  Section.Symbol->Aux[0].Aux.SectionDefinition.Number = I;
877  ++I;
878  };
879 
880  // Although it is not explicitly requested by the Microsoft COFF spec,
881  // we should avoid emitting forward associative section references,
882  // because MSVC link.exe as of 2017 cannot handle that.
883  for (const std::unique_ptr<COFFSection> &Section : Sections)
884  if (!isAssociative(*Section))
885  Assign(*Section);
886  for (const std::unique_ptr<COFFSection> &Section : Sections)
887  if (isAssociative(*Section))
888  Assign(*Section);
889 }
890 
891 // Assign file offsets to COFF object file structures.
892 void WinCOFFObjectWriter::assignFileOffsets(MCAssembler &Asm,
893  const MCAsmLayout &Layout) {
894  unsigned Offset = W.OS.tell();
895 
896  Offset += UseBigObj ? COFF::Header32Size : COFF::Header16Size;
897  Offset += COFF::SectionSize * Header.NumberOfSections;
898 
899  for (const auto &Section : Asm) {
900  COFFSection *Sec = SectionMap[&Section];
901 
902  if (Sec->Number == -1)
903  continue;
904 
905  Sec->Header.SizeOfRawData = Layout.getSectionAddressSize(&Section);
906 
907  if (IsPhysicalSection(Sec)) {
908  Sec->Header.PointerToRawData = Offset;
909  Offset += Sec->Header.SizeOfRawData;
910  }
911 
912  if (!Sec->Relocations.empty()) {
913  bool RelocationsOverflow = Sec->Relocations.size() >= 0xffff;
914 
915  if (RelocationsOverflow) {
916  // Signal overflow by setting NumberOfRelocations to max value. Actual
917  // size is found in reloc #0. Microsoft tools understand this.
918  Sec->Header.NumberOfRelocations = 0xffff;
919  } else {
920  Sec->Header.NumberOfRelocations = Sec->Relocations.size();
921  }
922  Sec->Header.PointerToRelocations = Offset;
923 
924  if (RelocationsOverflow) {
925  // Reloc #0 will contain actual count, so make room for it.
926  Offset += COFF::RelocationSize;
927  }
928 
929  Offset += COFF::RelocationSize * Sec->Relocations.size();
930 
931  for (auto &Relocation : Sec->Relocations) {
932  assert(Relocation.Symb->getIndex() != -1);
933  Relocation.Data.SymbolTableIndex = Relocation.Symb->getIndex();
934  }
935  }
936 
937  assert(Sec->Symbol->Aux.size() == 1 &&
938  "Section's symbol must have one aux!");
939  AuxSymbol &Aux = Sec->Symbol->Aux[0];
940  assert(Aux.AuxType == ATSectionDefinition &&
941  "Section's symbol's aux symbol must be a Section Definition!");
942  Aux.Aux.SectionDefinition.Length = Sec->Header.SizeOfRawData;
943  Aux.Aux.SectionDefinition.NumberOfRelocations =
944  Sec->Header.NumberOfRelocations;
945  Aux.Aux.SectionDefinition.NumberOfLinenumbers =
946  Sec->Header.NumberOfLineNumbers;
947  }
948 
949  Header.PointerToSymbolTable = Offset;
950 }
951 
952 uint64_t WinCOFFObjectWriter::writeObject(MCAssembler &Asm,
953  const MCAsmLayout &Layout) {
954  uint64_t StartOffset = W.OS.tell();
955 
956  if (Sections.size() > INT32_MAX)
958  "PE COFF object files can't have more than 2147483647 sections");
959 
960  UseBigObj = Sections.size() > COFF::MaxNumberOfSections16;
961  Header.NumberOfSections = Sections.size();
962  Header.NumberOfSymbols = 0;
963 
964  assignSectionNumbers();
965  createFileSymbols(Asm);
966 
967  for (auto &Symbol : Symbols) {
968  // Update section number & offset for symbols that have them.
969  if (Symbol->Section)
970  Symbol->Data.SectionNumber = Symbol->Section->Number;
971  Symbol->setIndex(Header.NumberOfSymbols++);
972  // Update auxiliary symbol info.
973  Symbol->Data.NumberOfAuxSymbols = Symbol->Aux.size();
974  Header.NumberOfSymbols += Symbol->Data.NumberOfAuxSymbols;
975  }
976 
977  // Build string table.
978  for (const auto &S : Sections)
979  if (S->Name.size() > COFF::NameSize)
980  Strings.add(S->Name);
981  for (const auto &S : Symbols)
982  if (S->Name.size() > COFF::NameSize)
983  Strings.add(S->Name);
984  Strings.finalize();
985 
986  // Set names.
987  for (const auto &S : Sections)
988  SetSectionName(*S);
989  for (auto &S : Symbols)
990  SetSymbolName(*S);
991 
992  // Fixup weak external references.
993  for (auto &Symbol : Symbols) {
994  if (Symbol->Other) {
995  assert(Symbol->getIndex() != -1);
996  assert(Symbol->Aux.size() == 1 && "Symbol must contain one aux symbol!");
997  assert(Symbol->Aux[0].AuxType == ATWeakExternal &&
998  "Symbol's aux symbol must be a Weak External!");
999  Symbol->Aux[0].Aux.WeakExternal.TagIndex = Symbol->Other->getIndex();
1000  }
1001  }
1002 
1003  // Fixup associative COMDAT sections.
1004  for (auto &Section : Sections) {
1005  if (Section->Symbol->Aux[0].Aux.SectionDefinition.Selection !=
1007  continue;
1008 
1009  const MCSectionCOFF &MCSec = *Section->MCSection;
1010  const MCSymbol *AssocMCSym = MCSec.getCOMDATSymbol();
1011  assert(AssocMCSym);
1012 
1013  // It's an error to try to associate with an undefined symbol or a symbol
1014  // without a section.
1015  if (!AssocMCSym->isInSection()) {
1016  Asm.getContext().reportError(
1017  SMLoc(), Twine("cannot make section ") + MCSec.getSectionName() +
1018  Twine(" associative with sectionless symbol ") +
1019  AssocMCSym->getName());
1020  continue;
1021  }
1022 
1023  const auto *AssocMCSec = cast<MCSectionCOFF>(&AssocMCSym->getSection());
1024  assert(SectionMap.count(AssocMCSec));
1025  COFFSection *AssocSec = SectionMap[AssocMCSec];
1026 
1027  // Skip this section if the associated section is unused.
1028  if (AssocSec->Number == -1)
1029  continue;
1030 
1031  Section->Symbol->Aux[0].Aux.SectionDefinition.Number = AssocSec->Number;
1032  }
1033 
1034  // Create the contents of the .llvm_addrsig section.
1035  if (EmitAddrsigSection) {
1036  auto Frag = new MCDataFragment(AddrsigSection);
1037  Frag->setLayoutOrder(0);
1038  raw_svector_ostream OS(Frag->getContents());
1039  for (const MCSymbol *S : AddrsigSyms) {
1040  if (!S->isTemporary()) {
1041  encodeULEB128(S->getIndex(), OS);
1042  continue;
1043  }
1044 
1045  MCSection *TargetSection = &S->getSection();
1046  assert(SectionMap.find(TargetSection) != SectionMap.end() &&
1047  "Section must already have been defined in "
1048  "executePostLayoutBinding!");
1049  encodeULEB128(SectionMap[TargetSection]->Symbol->getIndex(), OS);
1050  }
1051  }
1052 
1053  assignFileOffsets(Asm, Layout);
1054 
1055  // MS LINK expects to be able to use this timestamp to implement their
1056  // /INCREMENTAL feature.
1057  if (Asm.isIncrementalLinkerCompatible()) {
1058  Header.TimeDateStamp = getTime();
1059  } else {
1060  // Have deterministic output if /INCREMENTAL isn't needed. Also matches GNU.
1061  Header.TimeDateStamp = 0;
1062  }
1063 
1064  // Write it all to disk...
1065  WriteFileHeader(Header);
1066  writeSectionHeaders();
1067 
1068  // Write section contents.
1069  sections::iterator I = Sections.begin();
1070  sections::iterator IE = Sections.end();
1071  MCAssembler::iterator J = Asm.begin();
1072  MCAssembler::iterator JE = Asm.end();
1073  for (; I != IE && J != JE; ++I, ++J)
1074  writeSection(Asm, Layout, **I, *J);
1075 
1076  assert(W.OS.tell() == Header.PointerToSymbolTable &&
1077  "Header::PointerToSymbolTable is insane!");
1078 
1079  // Write a symbol table.
1080  for (auto &Symbol : Symbols)
1081  if (Symbol->getIndex() != -1)
1082  WriteSymbol(*Symbol);
1083 
1084  // Write a string table, which completes the entire COFF file.
1085  Strings.write(W.OS);
1086 
1087  return W.OS.tell() - StartOffset;
1088 }
1089 
1091  : Machine(Machine_) {}
1092 
1093 // Pin the vtable to this file.
1094 void MCWinCOFFObjectTargetWriter::anchor() {}
1095 
1096 //------------------------------------------------------------------------------
1097 // WinCOFFObjectWriter factory function
1098 
1099 std::unique_ptr<MCObjectWriter> llvm::createWinCOFFObjectWriter(
1100  std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS) {
1101  return llvm::make_unique<WinCOFFObjectWriter>(std::move(MOTW), OS);
1102 }
constexpr bool isUInt< 32 >(uint64_t x)
Definition: MathExtras.h:348
Instances of this class represent a uniqued identifier for a section in the current translation unit...
Definition: MCSection.h:38
uint32_t getCRC() const
Definition: JamCRC.h:41
static uint64_t getSymbolValue(const MCSymbol &Symbol, const MCAsmLayout &Layout)
uint32_t getIndex() const
Get the (implementation defined) index.
Definition: MCSymbol.h:312
LLVM_ATTRIBUTE_NORETURN void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:139
This class represents lattice values for constants.
Definition: AllocatorList.h:23
bool isVariable() const
isVariable - Check if this is a variable symbol.
Definition: MCSymbol.h:296
This represents an "assembler immediate".
Definition: MCValue.h:39
uint64_t getSectionAddressSize(const MCSection *Sec) const
Get the address space size of the given section, as it effects layout.
Definition: MCFragment.cpp:175
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:41
uint32_t SizeOfRawData
Definition: COFF.h:274
iterator begin()
Definition: MCAssembler.h:336
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
char Name[NameSize]
Definition: COFF.h:271
static void encodeBase64StringEntry(char *Buffer, uint64_t Value)
static std::time_t getTime()
A raw_ostream that writes to an SmallVector or SmallString.
Definition: raw_ostream.h:509
void write32le(void *P, uint32_t V)
Definition: Endian.h:418
bool isCommon() const
Is this a &#39;common&#39; symbol.
Definition: MCSymbol.h:382
Defines the object file and target independent interfaces used by the assembler backend to write nati...
uint16_t Machine
Definition: COFF.h:66
static const char BigObjMagic[]
Definition: COFF.h:38
MCSectionCOFF * getCOFFSection(StringRef Section, unsigned Characteristics, SectionKind Kind, StringRef COMDATSymName, int Selection, unsigned UniqueID=GenericSectionID, const char *BeginSymName=nullptr)
Definition: MCContext.cpp:425
Encode information on a single operation to perform on a byte sequence (e.g., an encoded instruction)...
Definition: MCFixup.h:74
unsigned getAlignment() const
Definition: MCSection.h:120
This represents a section on Windows.
Definition: MCSectionCOFF.h:26
MCContext & getContext() const
Definition: MCAssembler.h:284
int64_t getConstant() const
Definition: MCValue.h:46
const MCSymbolRefExpr * getSymB() const
Definition: MCValue.h:48
static uint32_t getAlignment(const MCSectionCOFF &Sec)
uint16_t Characteristics
Definition: COFF.h:72
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:80
Encapsulates the layout of an assembly file at a particular point in time.
Definition: MCAsmLayout.h:28
bool isInSection() const
isInSection - Check if this symbol is defined in some section (i.e., it is defined but not absolute)...
Definition: MCSymbol.h:252
bool registerSection(MCSection &Section)
uint32_t PointerToSymbolTable
Definition: COFF.h:69
Represent a reference to a symbol from inside an expression.
Definition: MCExpr.h:165
const int32_t MaxNumberOfSections16
Definition: COFF.h:33
ELFYAML::ELF_STO Other
Definition: ELFYAML.cpp:870
ArrayRef< std::string > getFileNames()
Definition: MCAssembler.h:442
Utility for building string tables with deduplicated suffixes.
A two-byte section relative fixup.
Definition: MCFixup.h:41
unsigned getCharacteristics() const
Definition: MCSectionCOFF.h:70
LLVM_NODISCARD size_t size() const
size - Get the string size.
Definition: StringRef.h:130
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:25
COFF::MachineTypes Machine
Definition: COFFYAML.cpp:365
Type is formed as (base + (derived << SCT_COMPLEX_TYPE_SHIFT))
Definition: COFF.h:265
iterator end()
Definition: MCAssembler.h:339
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:176
uint16_t SizeOfOptionalHeader
Definition: COFF.h:71
uint32_t SymbolTableIndex
Definition: COFF.h:326
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
Instrumentation for Order File
virtual void reset()
lifetime management
bool getSymbolOffset(const MCSymbol &S, uint64_t &Val) const
Get the offset of the given symbol, as computed in the current layout.
Definition: MCFragment.cpp:129
bool isTemporary() const
isTemporary - Check if this is an assembler temporary symbol.
Definition: MCSymbol.h:220
const MCSymbolRefExpr * getSymA() const
Definition: MCValue.h:47
uint64_t getCommonSize() const
Return the size of a &#39;common&#39; symbol.
Definition: MCSymbol.h:338
void reportError(SMLoc L, const Twine &Msg)
Definition: MCContext.cpp:644
DenseMap< SymbolStringPtr, JITEvaluatedSymbol > SymbolMap
A map from symbol names (as SymbolStringPtrs) to JITSymbols (address/flags pairs).
Definition: Core.h:48
uint32_t getOffset() const
Definition: MCFixup.h:125
void writeSectionData(raw_ostream &OS, const MCSection *Section, const MCAsmLayout &Layout) const
Emit the section contents to OS.
void toVector(SmallVectorImpl< char > &Out) const
Append the concatenated string into the given SmallString or SmallVector.
Definition: Twine.cpp:32
bool isExternal() const
Definition: MCSymbol.h:395
size_t size() const
Definition: SmallVector.h:52
StringRef getSectionName() const
Definition: MCSectionCOFF.h:69
static wasm::ValType getType(const TargetRegisterClass *RC)
uint16_t NumberOfLineNumbers
Definition: COFF.h:279
uint32_t VirtualAddress
Definition: COFF.h:273
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
std::unique_ptr< MCObjectWriter > createWinCOFFObjectWriter(std::unique_ptr< MCWinCOFFObjectTargetWriter > MOTW, raw_pwrite_stream &OS)
Construct a new Win COFF writer instance.
uint32_t TimeDateStamp
Definition: COFF.h:68
uint64_t getFragmentOffset(const MCFragment *F) const
Get the offset of the given fragment inside its containing section.
Definition: MCFragment.cpp:77
void sort(IteratorTy Start, IteratorTy End)
Definition: STLExtras.h:1122
PowerPC TLS Dynamic Call Fixup
SMLoc getLoc() const
Definition: MCFixup.h:166
COFFYAML::AuxSymbolType AuxType
Definition: COFFYAML.cpp:347
auto size(R &&Range, typename std::enable_if< std::is_same< typename std::iterator_traits< decltype(Range.begin())>::iterator_category, std::random_access_iterator_tag >::value, void >::type *=nullptr) -> decltype(std::distance(Range.begin(), Range.end()))
Get the size of a range.
Definition: STLExtras.h:1173
uint32_t PointerToRelocations
Definition: COFF.h:276
MCAsmBackend & getBackend() const
Definition: MCAssembler.h:292
MCSymbol * getCOMDATSymbol() const
Definition: MCSectionCOFF.h:71
unsigned encodeULEB128(uint64_t Value, raw_ostream &OS, unsigned PadTo=0)
Utility function to encode a ULEB128 value to an output stream.
Definition: LEB128.h:80
const MCSymbol & getSymbol() const
Definition: MCExpr.h:336
bool isUndefined(bool SetUsed=true) const
isUndefined - Check if this symbol undefined (i.e., implicitly defined).
Definition: MCSymbol.h:257
MCFragment * getFragment(bool SetUsed=true) const
Definition: MCSymbol.h:386
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:837
An iterator type that allows iterating over the pointees via some other iterator. ...
Definition: iterator.h:286
static SectionKind getMetadata()
Definition: SectionKind.h:178
uint32_t PointerToRawData
Definition: COFF.h:275
uint32_t VirtualSize
Definition: COFF.h:272
Target - Wrapper for Target specific information.
MCSection * getParent() const
Definition: MCFragment.h:98
int getSelection() const
Definition: MCSectionCOFF.h:72
MCSection & getSection() const
Get the section associated with a defined, non-absolute symbol.
Definition: MCSymbol.h:267
uint32_t NumberOfSymbols
Definition: COFF.h:70
virtual bool isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, const MCSymbol &A, const MCSymbol &B, bool InSet) const
Adapter to write values to a stream in a particular byte order.
Definition: EndianStream.h:51
pointer data()
Return a pointer to the vector&#39;s buffer, even if empty().
Definition: SmallVector.h:144
int32_t NumberOfSections
Definition: COFF.h:67
#define I(x, y, z)
Definition: MD5.cpp:58
iterator end()
Definition: DenseMap.h:108
LLVM_NODISCARD std::enable_if<!is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type >::type dyn_cast(const Y &Val)
Definition: Casting.h:332
uint16_t getClass() const
Definition: MCSymbolCOFF.h:40
StringRef getName() const
getName - Get the symbol name.
Definition: MCSymbol.h:203
An abstract base class for streams implementations that also support a pwrite operation.
Definition: raw_ostream.h:340
Fragment for data and encoded instructions.
Definition: MCFragment.h:241
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
uint16_t NumberOfRelocations
Definition: COFF.h:278
bool isIncrementalLinkerCompatible() const
Definition: MCAssembler.h:313
const MCExpr * getVariableValue(bool SetUsed=true) const
getVariableValue - Get the value for variable symbols.
Definition: MCSymbol.h:301
LLVM Value Representation.
Definition: Value.h:72
static const char * name
void update(ArrayRef< char > Data)
Definition: JamCRC.cpp:91
uint32_t PointerToLineNumbers
Definition: COFF.h:277
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
uint16_t getType() const
Definition: MCSymbolCOFF.h:33
Represents a location in source code.
Definition: SMLoc.h:23
static bool isAssociative(const COFFSection &Section)
uint32_t Characteristics
Definition: COFF.h:280
void setIndex(uint32_t Value) const
Set the (implementation defined) index.
Definition: MCSymbol.h:317
Twine concat(const Twine &Suffix) const
Definition: Twine.h:488
const MCSymbol * getBaseSymbol(const MCSymbol &Symbol) const
If this symbol is equivalent to A + Constant, return A.
Definition: MCFragment.cpp:139
uint32_t VirtualAddress
Definition: COFF.h:325
A function that returns a base type.
Definition: COFF.h:261