LLVM 19.0.0git
WinCOFFObjectWriter.cpp
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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/DenseSet.h"
15#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/StringRef.h"
19#include "llvm/ADT/Twine.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"
27#include "llvm/MC/MCSection.h"
29#include "llvm/MC/MCSymbol.h"
31#include "llvm/MC/MCValue.h"
34#include "llvm/Support/CRC.h"
38#include "llvm/Support/LEB128.h"
41#include <algorithm>
42#include <cassert>
43#include <cstdint>
44#include <cstring>
45#include <ctime>
46#include <memory>
47#include <string>
48#include <vector>
49
50using namespace llvm;
52
53#define DEBUG_TYPE "WinCOFFObjectWriter"
54
55namespace {
56
57constexpr int OffsetLabelIntervalBits = 20;
58
60
61enum AuxiliaryType { ATWeakExternal, ATFile, ATSectionDefinition };
62
63struct AuxSymbol {
64 AuxiliaryType AuxType;
66};
67
68class COFFSection;
69
70class COFFSymbol {
71public:
72 COFF::symbol Data = {};
73
74 using AuxiliarySymbols = SmallVector<AuxSymbol, 1>;
75
76 name Name;
77 int Index = 0;
78 AuxiliarySymbols Aux;
79 COFFSymbol *Other = nullptr;
80 COFFSection *Section = nullptr;
81 int Relocations = 0;
82 const MCSymbol *MC = nullptr;
83
84 COFFSymbol(StringRef Name) : Name(Name) {}
85
86 void set_name_offset(uint32_t Offset);
87
88 int64_t getIndex() const { return Index; }
89 void setIndex(int Value) {
90 Index = Value;
91 if (MC)
92 MC->setIndex(static_cast<uint32_t>(Value));
93 }
94};
95
96// This class contains staging data for a COFF relocation entry.
97struct COFFRelocation {
99 COFFSymbol *Symb = nullptr;
100
101 COFFRelocation() = default;
102
103 static size_t size() { return COFF::RelocationSize; }
104};
105
106using relocations = std::vector<COFFRelocation>;
107
108class COFFSection {
109public:
110 COFF::section Header = {};
111
112 std::string Name;
113 int Number = 0;
114 MCSectionCOFF const *MCSection = nullptr;
115 COFFSymbol *Symbol = nullptr;
116 relocations Relocations;
117
118 COFFSection(StringRef Name) : Name(std::string(Name)) {}
119
120 SmallVector<COFFSymbol *, 1> OffsetSymbols;
121};
122} // namespace
123
125 WinCOFFObjectWriter &OWriter;
127
128 using symbols = std::vector<std::unique_ptr<COFFSymbol>>;
129 using sections = std::vector<std::unique_ptr<COFFSection>>;
130
133
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 symbol_list WeakDefaults;
147
148 bool UseBigObj;
149 bool UseOffsetLabels = false;
150
151public:
152 enum DwoMode {
157
159 DwoMode Mode);
160
161 void reset();
163 void recordRelocation(MCAssembler &Asm, const MCFragment *Fragment,
164 const MCFixup &Fixup, MCValue Target,
165 uint64_t &FixedValue);
167
168private:
169 COFFSymbol *createSymbol(StringRef Name);
170 COFFSymbol *GetOrCreateCOFFSymbol(const MCSymbol *Symbol);
171 COFFSection *createSection(StringRef Name);
172
173 void defineSection(const MCAssembler &Asm, MCSectionCOFF const &Sec);
174
175 COFFSymbol *getLinkedSymbol(const MCSymbol &Symbol);
176 void defineSymbol(const MCAssembler &Asm, const MCSymbol &Symbol);
177
178 void SetSymbolName(COFFSymbol &S);
179 void SetSectionName(COFFSection &S);
180
181 bool IsPhysicalSection(COFFSection *S);
182
183 // Entity writing methods.
184 void WriteFileHeader(const COFF::header &Header);
185 void WriteSymbol(const COFFSymbol &S);
186 void WriteAuxiliarySymbols(const COFFSymbol::AuxiliarySymbols &S);
187 void writeSectionHeaders();
188 void WriteRelocation(const COFF::relocation &R);
189 uint32_t writeSectionContents(MCAssembler &Asm, const MCSection &MCSec);
190 void writeSection(MCAssembler &Asm, const COFFSection &Sec);
191
192 void createFileSymbols(MCAssembler &Asm);
193 void setWeakDefaultNames();
194 void assignSectionNumbers();
195 void assignFileOffsets(MCAssembler &Asm);
196};
197
199 std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS)
200 : TargetObjectWriter(std::move(MOTW)),
201 ObjWriter(std::make_unique<WinCOFFWriter>(*this, OS,
202 WinCOFFWriter::AllSections)) {}
204 std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS,
205 raw_pwrite_stream &DwoOS)
206 : TargetObjectWriter(std::move(MOTW)),
207 ObjWriter(std::make_unique<WinCOFFWriter>(*this, OS,
208 WinCOFFWriter::NonDwoOnly)),
209 DwoWriter(std::make_unique<WinCOFFWriter>(*this, DwoOS,
210 WinCOFFWriter::DwoOnly)) {}
211
212static bool isDwoSection(const MCSection &Sec) {
213 return Sec.getName().ends_with(".dwo");
214}
215
216//------------------------------------------------------------------------------
217// Symbol class implementation
218
219// In the case that the name does not fit within 8 bytes, the offset
220// into the string table is stored in the last 4 bytes instead, leaving
221// the first 4 bytes as 0.
222void COFFSymbol::set_name_offset(uint32_t Offset) {
223 write32le(Data.Name + 0, 0);
224 write32le(Data.Name + 4, Offset);
225}
226
227//------------------------------------------------------------------------------
228// WinCOFFWriter class implementation
229
232 : OWriter(OWriter), W(OS, llvm::endianness::little), Mode(Mode) {
233 Header.Machine = OWriter.TargetObjectWriter->getMachine();
234 // Some relocations on ARM64 (the 21 bit ADRP relocations) have a slightly
235 // limited range for the immediate offset (+/- 1 MB); create extra offset
236 // label symbols with regular intervals to allow referencing a
237 // non-temporary symbol that is close enough.
238 UseOffsetLabels = COFF::isAnyArm64(Header.Machine);
239}
240
241COFFSymbol *WinCOFFWriter::createSymbol(StringRef Name) {
242 Symbols.push_back(std::make_unique<COFFSymbol>(Name));
243 return Symbols.back().get();
244}
245
246COFFSymbol *WinCOFFWriter::GetOrCreateCOFFSymbol(const MCSymbol *Symbol) {
247 COFFSymbol *&Ret = SymbolMap[Symbol];
248 if (!Ret)
249 Ret = createSymbol(Symbol->getName());
250 return Ret;
251}
252
253COFFSection *WinCOFFWriter::createSection(StringRef Name) {
254 Sections.emplace_back(std::make_unique<COFFSection>(Name));
255 return Sections.back().get();
256}
257
259 switch (Sec.getAlign().value()) {
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.
294void WinCOFFWriter::defineSection(const MCAssembler &Asm,
295 const MCSectionCOFF &MCSec) {
296 COFFSection *Section = createSection(MCSec.getName());
297 COFFSymbol *Symbol = createSymbol(MCSec.getName());
298 Section->Symbol = Symbol;
299 SymbolMap[MCSec.getBeginSymbol()] = Symbol;
300 Symbol->Section = Section;
301 Symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_STATIC;
302
303 // Create a COMDAT symbol if needed.
305 if (const MCSymbol *S = MCSec.getCOMDATSymbol()) {
306 COFFSymbol *COMDATSymbol = GetOrCreateCOFFSymbol(S);
307 if (COMDATSymbol->Section)
308 report_fatal_error("two sections have the same comdat");
309 COMDATSymbol->Section = Section;
310 }
311 }
312
313 // In this case the auxiliary symbol is a Section Definition.
314 Symbol->Aux.resize(1);
315 Symbol->Aux[0] = {};
316 Symbol->Aux[0].AuxType = ATSectionDefinition;
317 Symbol->Aux[0].Aux.SectionDefinition.Selection = MCSec.getSelection();
318
319 // Set section alignment.
320 Section->Header.Characteristics = MCSec.getCharacteristics();
321 Section->Header.Characteristics |= getAlignment(MCSec);
322
323 // Bind internal COFF section to MC section.
324 Section->MCSection = &MCSec;
325 SectionMap[&MCSec] = Section;
326
327 if (UseOffsetLabels && !MCSec.empty()) {
328 const uint32_t Interval = 1 << OffsetLabelIntervalBits;
329 uint32_t N = 1;
330 for (uint32_t Off = Interval, E = Asm.getSectionAddressSize(MCSec); Off < E;
331 Off += Interval) {
332 auto Name = ("$L" + MCSec.getName() + "_" + Twine(N++)).str();
333 COFFSymbol *Label = createSymbol(Name);
334 Label->Section = Section;
335 Label->Data.StorageClass = COFF::IMAGE_SYM_CLASS_LABEL;
336 Label->Data.Value = Off;
337 Section->OffsetSymbols.push_back(Label);
338 }
339 }
340}
341
342static uint64_t getSymbolValue(const MCSymbol &Symbol, const MCAssembler &Asm) {
343 if (Symbol.isCommon() && Symbol.isExternal())
344 return Symbol.getCommonSize();
345
346 uint64_t Res;
347 if (!Asm.getSymbolOffset(Symbol, Res))
348 return 0;
349
350 return Res;
351}
352
353COFFSymbol *WinCOFFWriter::getLinkedSymbol(const MCSymbol &Symbol) {
354 if (!Symbol.isVariable())
355 return nullptr;
356
357 const MCSymbolRefExpr *SymRef =
358 dyn_cast<MCSymbolRefExpr>(Symbol.getVariableValue());
359 if (!SymRef)
360 return nullptr;
361
362 const MCSymbol &Aliasee = SymRef->getSymbol();
363 if (Aliasee.isUndefined() || Aliasee.isExternal())
364 return GetOrCreateCOFFSymbol(&Aliasee);
365 else
366 return nullptr;
367}
368
369/// This function takes a symbol data object from the assembler
370/// and creates the associated COFF symbol staging object.
371void WinCOFFWriter::defineSymbol(const MCAssembler &Asm,
372 const MCSymbol &MCSym) {
373 const MCSymbol *Base = Asm.getBaseSymbol(MCSym);
374 COFFSection *Sec = nullptr;
375 MCSectionCOFF *MCSec = nullptr;
376 if (Base && Base->getFragment()) {
377 MCSec = cast<MCSectionCOFF>(Base->getFragment()->getParent());
378 Sec = SectionMap[MCSec];
379 }
380
381 if (Mode == NonDwoOnly && MCSec && isDwoSection(*MCSec))
382 return;
383
384 COFFSymbol *Sym = GetOrCreateCOFFSymbol(&MCSym);
385 COFFSymbol *Local = nullptr;
386 if (cast<MCSymbolCOFF>(MCSym).getWeakExternalCharacteristics()) {
387 Sym->Data.StorageClass = COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL;
388 Sym->Section = nullptr;
389
390 COFFSymbol *WeakDefault = getLinkedSymbol(MCSym);
391 if (!WeakDefault) {
392 std::string WeakName = (".weak." + MCSym.getName() + ".default").str();
393 WeakDefault = createSymbol(WeakName);
394 if (!Sec)
395 WeakDefault->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE;
396 else
397 WeakDefault->Section = Sec;
398 WeakDefaults.insert(WeakDefault);
399 Local = WeakDefault;
400 }
401
402 Sym->Other = WeakDefault;
403
404 // Setup the Weak External auxiliary symbol.
405 Sym->Aux.resize(1);
406 memset(&Sym->Aux[0], 0, sizeof(Sym->Aux[0]));
407 Sym->Aux[0].AuxType = ATWeakExternal;
408 Sym->Aux[0].Aux.WeakExternal.TagIndex = 0; // Filled in later
409 Sym->Aux[0].Aux.WeakExternal.Characteristics =
410 cast<MCSymbolCOFF>(MCSym).getWeakExternalCharacteristics();
411 } else {
412 if (!Base)
413 Sym->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE;
414 else
415 Sym->Section = Sec;
416 Local = Sym;
417 }
418
419 if (Local) {
420 Local->Data.Value = getSymbolValue(MCSym, Asm);
421
422 const MCSymbolCOFF &SymbolCOFF = cast<MCSymbolCOFF>(MCSym);
423 Local->Data.Type = SymbolCOFF.getType();
424 Local->Data.StorageClass = SymbolCOFF.getClass();
425
426 // If no storage class was specified in the streamer, define it here.
427 if (Local->Data.StorageClass == COFF::IMAGE_SYM_CLASS_NULL) {
428 bool IsExternal =
429 MCSym.isExternal() || (!MCSym.getFragment() && !MCSym.isVariable());
430
431 Local->Data.StorageClass = IsExternal ? COFF::IMAGE_SYM_CLASS_EXTERNAL
433 }
434 }
435
436 Sym->MC = &MCSym;
437}
438
439void WinCOFFWriter::SetSectionName(COFFSection &S) {
440 if (S.Name.size() <= COFF::NameSize) {
441 std::memcpy(S.Header.Name, S.Name.c_str(), S.Name.size());
442 return;
443 }
444
445 uint64_t StringTableEntry = Strings.getOffset(S.Name);
446 if (!COFF::encodeSectionName(S.Header.Name, StringTableEntry))
447 report_fatal_error("COFF string table is greater than 64 GB.");
448}
449
450void WinCOFFWriter::SetSymbolName(COFFSymbol &S) {
451 if (S.Name.size() > COFF::NameSize)
452 S.set_name_offset(Strings.getOffset(S.Name));
453 else
454 std::memcpy(S.Data.Name, S.Name.c_str(), S.Name.size());
455}
456
457bool WinCOFFWriter::IsPhysicalSection(COFFSection *S) {
458 return (S->Header.Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA) ==
459 0;
460}
461
462//------------------------------------------------------------------------------
463// entity writing methods
464
465void WinCOFFWriter::WriteFileHeader(const COFF::header &Header) {
466 if (UseBigObj) {
468 W.write<uint16_t>(0xFFFF);
470 W.write<uint16_t>(Header.Machine);
471 W.write<uint32_t>(Header.TimeDateStamp);
473 W.write<uint32_t>(0);
474 W.write<uint32_t>(0);
475 W.write<uint32_t>(0);
476 W.write<uint32_t>(0);
477 W.write<uint32_t>(Header.NumberOfSections);
478 W.write<uint32_t>(Header.PointerToSymbolTable);
479 W.write<uint32_t>(Header.NumberOfSymbols);
480 } else {
481 W.write<uint16_t>(Header.Machine);
482 W.write<uint16_t>(static_cast<int16_t>(Header.NumberOfSections));
483 W.write<uint32_t>(Header.TimeDateStamp);
484 W.write<uint32_t>(Header.PointerToSymbolTable);
485 W.write<uint32_t>(Header.NumberOfSymbols);
486 W.write<uint16_t>(Header.SizeOfOptionalHeader);
487 W.write<uint16_t>(Header.Characteristics);
488 }
489}
490
491void WinCOFFWriter::WriteSymbol(const COFFSymbol &S) {
492 W.OS.write(S.Data.Name, COFF::NameSize);
493 W.write<uint32_t>(S.Data.Value);
494 if (UseBigObj)
495 W.write<uint32_t>(S.Data.SectionNumber);
496 else
497 W.write<uint16_t>(static_cast<int16_t>(S.Data.SectionNumber));
498 W.write<uint16_t>(S.Data.Type);
499 W.OS << char(S.Data.StorageClass);
500 W.OS << char(S.Data.NumberOfAuxSymbols);
501 WriteAuxiliarySymbols(S.Aux);
502}
503
504void WinCOFFWriter::WriteAuxiliarySymbols(
506 for (const AuxSymbol &i : S) {
507 switch (i.AuxType) {
508 case ATWeakExternal:
509 W.write<uint32_t>(i.Aux.WeakExternal.TagIndex);
510 W.write<uint32_t>(i.Aux.WeakExternal.Characteristics);
511 W.OS.write_zeros(sizeof(i.Aux.WeakExternal.unused));
512 if (UseBigObj)
514 break;
515 case ATFile:
516 W.OS.write(reinterpret_cast<const char *>(&i.Aux),
518 break;
519 case ATSectionDefinition:
520 W.write<uint32_t>(i.Aux.SectionDefinition.Length);
521 W.write<uint16_t>(i.Aux.SectionDefinition.NumberOfRelocations);
522 W.write<uint16_t>(i.Aux.SectionDefinition.NumberOfLinenumbers);
523 W.write<uint32_t>(i.Aux.SectionDefinition.CheckSum);
524 W.write<uint16_t>(static_cast<int16_t>(i.Aux.SectionDefinition.Number));
525 W.OS << char(i.Aux.SectionDefinition.Selection);
526 W.OS.write_zeros(sizeof(i.Aux.SectionDefinition.unused));
527 W.write<uint16_t>(
528 static_cast<int16_t>(i.Aux.SectionDefinition.Number >> 16));
529 if (UseBigObj)
531 break;
532 }
533 }
534}
535
536// Write the section header.
537void WinCOFFWriter::writeSectionHeaders() {
538 // Section numbers must be monotonically increasing in the section
539 // header, but our Sections array is not sorted by section number,
540 // so make a copy of Sections and sort it.
541 std::vector<COFFSection *> Arr;
542 for (auto &Section : Sections)
543 Arr.push_back(Section.get());
544 llvm::sort(Arr, [](const COFFSection *A, const COFFSection *B) {
545 return A->Number < B->Number;
546 });
547
548 for (auto &Section : Arr) {
549 if (Section->Number == -1)
550 continue;
551
552 COFF::section &S = Section->Header;
553 if (Section->Relocations.size() >= 0xffff)
565 }
566}
567
568void WinCOFFWriter::WriteRelocation(const COFF::relocation &R) {
569 W.write<uint32_t>(R.VirtualAddress);
570 W.write<uint32_t>(R.SymbolTableIndex);
571 W.write<uint16_t>(R.Type);
572}
573
574// Write MCSec's contents. What this function does is essentially
575// "Asm.writeSectionData(&MCSec)", but it's a bit complicated
576// because it needs to compute a CRC.
577uint32_t WinCOFFWriter::writeSectionContents(MCAssembler &Asm,
578 const MCSection &MCSec) {
579 // Save the contents of the section to a temporary buffer, we need this
580 // to CRC the data before we dump it into the object file.
582 raw_svector_ostream VecOS(Buf);
583 Asm.writeSectionData(VecOS, &MCSec);
584
585 // Write the section contents to the object file.
586 W.OS << Buf;
587
588 // Calculate our CRC with an initial value of '0', this is not how
589 // JamCRC is specified but it aligns with the expected output.
590 JamCRC JC(/*Init=*/0);
591 JC.update(ArrayRef(reinterpret_cast<uint8_t *>(Buf.data()), Buf.size()));
592 return JC.getCRC();
593}
594
595void WinCOFFWriter::writeSection(MCAssembler &Asm, const COFFSection &Sec) {
596 if (Sec.Number == -1)
597 return;
598
599 // Write the section contents.
600 if (Sec.Header.PointerToRawData != 0) {
601 assert(W.OS.tell() == Sec.Header.PointerToRawData &&
602 "Section::PointerToRawData is insane!");
603
604 uint32_t CRC = writeSectionContents(Asm, *Sec.MCSection);
605
606 // Update the section definition auxiliary symbol to record the CRC.
607 COFFSymbol::AuxiliarySymbols &AuxSyms = Sec.Symbol->Aux;
608 assert(AuxSyms.size() == 1 && AuxSyms[0].AuxType == ATSectionDefinition);
609 AuxSymbol &SecDef = AuxSyms[0];
610 SecDef.Aux.SectionDefinition.CheckSum = CRC;
611 }
612
613 // Write relocations for this section.
614 if (Sec.Relocations.empty()) {
615 assert(Sec.Header.PointerToRelocations == 0 &&
616 "Section::PointerToRelocations is insane!");
617 return;
618 }
619
620 assert(W.OS.tell() == Sec.Header.PointerToRelocations &&
621 "Section::PointerToRelocations is insane!");
622
623 if (Sec.Relocations.size() >= 0xffff) {
624 // In case of overflow, write actual relocation count as first
625 // relocation. Including the synthetic reloc itself (+ 1).
627 R.VirtualAddress = Sec.Relocations.size() + 1;
628 R.SymbolTableIndex = 0;
629 R.Type = 0;
630 WriteRelocation(R);
631 }
632
633 for (const auto &Relocation : Sec.Relocations)
634 WriteRelocation(Relocation.Data);
635}
636
637// Create .file symbols.
638void WinCOFFWriter::createFileSymbols(MCAssembler &Asm) {
639 for (const std::pair<std::string, size_t> &It : Asm.getFileNames()) {
640 // round up to calculate the number of auxiliary symbols required
641 const std::string &Name = It.first;
642 unsigned SymbolSize = UseBigObj ? COFF::Symbol32Size : COFF::Symbol16Size;
643 unsigned Count = (Name.size() + SymbolSize - 1) / SymbolSize;
644
645 COFFSymbol *File = createSymbol(".file");
646 File->Data.SectionNumber = COFF::IMAGE_SYM_DEBUG;
647 File->Data.StorageClass = COFF::IMAGE_SYM_CLASS_FILE;
648 File->Aux.resize(Count);
649
650 unsigned Offset = 0;
651 unsigned Length = Name.size();
652 for (auto &Aux : File->Aux) {
653 Aux.AuxType = ATFile;
654
655 if (Length > SymbolSize) {
656 memcpy(&Aux.Aux, Name.c_str() + Offset, SymbolSize);
657 Length = Length - SymbolSize;
658 } else {
659 memcpy(&Aux.Aux, Name.c_str() + Offset, Length);
660 memset((char *)&Aux.Aux + Length, 0, SymbolSize - Length);
661 break;
662 }
663
664 Offset += SymbolSize;
665 }
666 }
667}
668
669void WinCOFFWriter::setWeakDefaultNames() {
670 if (WeakDefaults.empty())
671 return;
672
673 // If multiple object files use a weak symbol (either with a regular
674 // defined default, or an absolute zero symbol as default), the defaults
675 // cause duplicate definitions unless their names are made unique. Look
676 // for a defined extern symbol, that isn't comdat - that should be unique
677 // unless there are other duplicate definitions. And if none is found,
678 // allow picking a comdat symbol, as that's still better than nothing.
679
680 COFFSymbol *Unique = nullptr;
681 for (bool AllowComdat : {false, true}) {
682 for (auto &Sym : Symbols) {
683 // Don't include the names of the defaults themselves
684 if (WeakDefaults.count(Sym.get()))
685 continue;
686 // Only consider external symbols
687 if (Sym->Data.StorageClass != COFF::IMAGE_SYM_CLASS_EXTERNAL)
688 continue;
689 // Only consider symbols defined in a section or that are absolute
690 if (!Sym->Section && Sym->Data.SectionNumber != COFF::IMAGE_SYM_ABSOLUTE)
691 continue;
692 if (!AllowComdat && Sym->Section &&
693 Sym->Section->Header.Characteristics & COFF::IMAGE_SCN_LNK_COMDAT)
694 continue;
695 Unique = Sym.get();
696 break;
697 }
698 if (Unique)
699 break;
700 }
701 // If we didn't find any unique symbol to use for the names, just skip this.
702 if (!Unique)
703 return;
704 for (auto *Sym : WeakDefaults) {
705 Sym->Name.append(".");
706 Sym->Name.append(Unique->Name);
707 }
708}
709
710static bool isAssociative(const COFFSection &Section) {
711 return Section.Symbol->Aux[0].Aux.SectionDefinition.Selection ==
713}
714
715void WinCOFFWriter::assignSectionNumbers() {
716 size_t I = 1;
717 auto Assign = [&](COFFSection &Section) {
718 Section.Number = I;
719 Section.Symbol->Data.SectionNumber = I;
720 Section.Symbol->Aux[0].Aux.SectionDefinition.Number = I;
721 ++I;
722 };
723
724 // Although it is not explicitly requested by the Microsoft COFF spec,
725 // we should avoid emitting forward associative section references,
726 // because MSVC link.exe as of 2017 cannot handle that.
727 for (const std::unique_ptr<COFFSection> &Section : Sections)
728 if (!isAssociative(*Section))
729 Assign(*Section);
730 for (const std::unique_ptr<COFFSection> &Section : Sections)
731 if (isAssociative(*Section))
732 Assign(*Section);
733}
734
735// Assign file offsets to COFF object file structures.
736void WinCOFFWriter::assignFileOffsets(MCAssembler &Asm) {
737 unsigned Offset = W.OS.tell();
738
740 Offset += COFF::SectionSize * Header.NumberOfSections;
741
742 for (const auto &Section : Asm) {
743 COFFSection *Sec = SectionMap[&Section];
744
745 if (!Sec || Sec->Number == -1)
746 continue;
747
748 Sec->Header.SizeOfRawData = Asm.getSectionAddressSize(Section);
749
750 if (IsPhysicalSection(Sec)) {
751 Sec->Header.PointerToRawData = Offset;
752 Offset += Sec->Header.SizeOfRawData;
753 }
754
755 if (!Sec->Relocations.empty()) {
756 bool RelocationsOverflow = Sec->Relocations.size() >= 0xffff;
757
758 if (RelocationsOverflow) {
759 // Signal overflow by setting NumberOfRelocations to max value. Actual
760 // size is found in reloc #0. Microsoft tools understand this.
761 Sec->Header.NumberOfRelocations = 0xffff;
762 } else {
763 Sec->Header.NumberOfRelocations = Sec->Relocations.size();
764 }
765 Sec->Header.PointerToRelocations = Offset;
766
767 if (RelocationsOverflow) {
768 // Reloc #0 will contain actual count, so make room for it.
770 }
771
772 Offset += COFF::RelocationSize * Sec->Relocations.size();
773
774 for (auto &Relocation : Sec->Relocations) {
775 assert(Relocation.Symb->getIndex() != -1);
776 Relocation.Data.SymbolTableIndex = Relocation.Symb->getIndex();
777 }
778 }
779
780 assert(Sec->Symbol->Aux.size() == 1 &&
781 "Section's symbol must have one aux!");
782 AuxSymbol &Aux = Sec->Symbol->Aux[0];
783 assert(Aux.AuxType == ATSectionDefinition &&
784 "Section's symbol's aux symbol must be a Section Definition!");
785 Aux.Aux.SectionDefinition.Length = Sec->Header.SizeOfRawData;
786 Aux.Aux.SectionDefinition.NumberOfRelocations =
787 Sec->Header.NumberOfRelocations;
788 Aux.Aux.SectionDefinition.NumberOfLinenumbers =
789 Sec->Header.NumberOfLineNumbers;
790 }
791
792 Header.PointerToSymbolTable = Offset;
793}
794
796 memset(&Header, 0, sizeof(Header));
797 Header.Machine = OWriter.TargetObjectWriter->getMachine();
798 Sections.clear();
799 Symbols.clear();
800 Strings.clear();
801 SectionMap.clear();
802 SymbolMap.clear();
803 WeakDefaults.clear();
804}
805
807 // "Define" each section & symbol. This creates section & symbol
808 // entries in the staging area.
809 for (const auto &Section : Asm) {
810 if ((Mode == NonDwoOnly && isDwoSection(Section)) ||
811 (Mode == DwoOnly && !isDwoSection(Section)))
812 continue;
813 defineSection(Asm, static_cast<const MCSectionCOFF &>(Section));
814 }
815
816 if (Mode != DwoOnly)
817 for (const MCSymbol &Symbol : Asm.symbols())
818 // Define non-temporary or temporary static (private-linkage) symbols
819 if (!Symbol.isTemporary() ||
820 cast<MCSymbolCOFF>(Symbol).getClass() == COFF::IMAGE_SYM_CLASS_STATIC)
821 defineSymbol(Asm, Symbol);
822}
823
825 const MCFragment *Fragment,
826 const MCFixup &Fixup, MCValue Target,
827 uint64_t &FixedValue) {
828 assert(Target.getSymA() && "Relocation must reference a symbol!");
829
830 const MCSymbol &A = Target.getSymA()->getSymbol();
831 if (!A.isRegistered()) {
832 Asm.getContext().reportError(Fixup.getLoc(), Twine("symbol '") +
833 A.getName() +
834 "' can not be undefined");
835 return;
836 }
837 if (A.isTemporary() && A.isUndefined()) {
838 Asm.getContext().reportError(Fixup.getLoc(), Twine("assembler label '") +
839 A.getName() +
840 "' can not be undefined");
841 return;
842 }
843
844 MCSection *MCSec = Fragment->getParent();
845
846 // Mark this symbol as requiring an entry in the symbol table.
847 assert(SectionMap.contains(MCSec) &&
848 "Section must already have been defined in executePostLayoutBinding!");
849
850 COFFSection *Sec = SectionMap[MCSec];
851 const MCSymbolRefExpr *SymB = Target.getSymB();
852
853 if (SymB) {
854 const MCSymbol *B = &SymB->getSymbol();
855 if (!B->getFragment()) {
856 Asm.getContext().reportError(
857 Fixup.getLoc(),
858 Twine("symbol '") + B->getName() +
859 "' can not be undefined in a subtraction expression");
860 return;
861 }
862
863 // Offset of the symbol in the section
864 int64_t OffsetOfB = Asm.getSymbolOffset(*B);
865
866 // Offset of the relocation in the section
867 int64_t OffsetOfRelocation =
868 Asm.getFragmentOffset(*Fragment) + Fixup.getOffset();
869
870 FixedValue = (OffsetOfRelocation - OffsetOfB) + Target.getConstant();
871 } else {
872 FixedValue = Target.getConstant();
873 }
874
875 COFFRelocation Reloc;
876
877 Reloc.Data.SymbolTableIndex = 0;
878 Reloc.Data.VirtualAddress = Asm.getFragmentOffset(*Fragment);
879
880 // Turn relocations for temporary symbols into section relocations.
881 if (A.isTemporary() && !SymbolMap[&A]) {
882 MCSection *TargetSection = &A.getSection();
883 assert(
884 SectionMap.contains(TargetSection) &&
885 "Section must already have been defined in executePostLayoutBinding!");
886 COFFSection *Section = SectionMap[TargetSection];
887 Reloc.Symb = Section->Symbol;
888 FixedValue += Asm.getSymbolOffset(A);
889 // Technically, we should do the final adjustments of FixedValue (below)
890 // before picking an offset symbol, otherwise we might choose one which
891 // is slightly too far away. The relocations where it really matters
892 // (arm64 adrp relocations) don't get any offset though.
893 if (UseOffsetLabels && !Section->OffsetSymbols.empty()) {
894 uint64_t LabelIndex = FixedValue >> OffsetLabelIntervalBits;
895 if (LabelIndex > 0) {
896 if (LabelIndex <= Section->OffsetSymbols.size())
897 Reloc.Symb = Section->OffsetSymbols[LabelIndex - 1];
898 else
899 Reloc.Symb = Section->OffsetSymbols.back();
900 FixedValue -= Reloc.Symb->Data.Value;
901 }
902 }
903 } else {
904 assert(
905 SymbolMap.contains(&A) &&
906 "Symbol must already have been defined in executePostLayoutBinding!");
907 Reloc.Symb = SymbolMap[&A];
908 }
909
910 ++Reloc.Symb->Relocations;
911
912 Reloc.Data.VirtualAddress += Fixup.getOffset();
913 Reloc.Data.Type = OWriter.TargetObjectWriter->getRelocType(
914 Asm.getContext(), Target, Fixup, SymB, Asm.getBackend());
915
916 // The *_REL32 relocations are relative to the end of the relocation,
917 // not to the start.
918 if ((Header.Machine == COFF::IMAGE_FILE_MACHINE_AMD64 &&
919 Reloc.Data.Type == COFF::IMAGE_REL_AMD64_REL32) ||
920 (Header.Machine == COFF::IMAGE_FILE_MACHINE_I386 &&
921 Reloc.Data.Type == COFF::IMAGE_REL_I386_REL32) ||
922 (Header.Machine == COFF::IMAGE_FILE_MACHINE_ARMNT &&
923 Reloc.Data.Type == COFF::IMAGE_REL_ARM_REL32) ||
924 (COFF::isAnyArm64(Header.Machine) &&
925 Reloc.Data.Type == COFF::IMAGE_REL_ARM64_REL32))
926 FixedValue += 4;
927
928 if (Header.Machine == COFF::IMAGE_FILE_MACHINE_ARMNT) {
929 switch (Reloc.Data.Type) {
936 break;
939 // IMAGE_REL_ARM_BRANCH11 and IMAGE_REL_ARM_BLX11 are only used for
940 // pre-ARMv7, which implicitly rules it out of ARMNT (it would be valid
941 // for Windows CE).
945 // IMAGE_REL_ARM_BRANCH24, IMAGE_REL_ARM_BLX24, IMAGE_REL_ARM_MOV32A are
946 // only used for ARM mode code, which is documented as being unsupported
947 // by Windows on ARM. Empirical proof indicates that masm is able to
948 // generate the relocations however the rest of the MSVC toolchain is
949 // unable to handle it.
950 llvm_unreachable("unsupported relocation");
951 break;
953 break;
957 // IMAGE_REL_BRANCH20T, IMAGE_REL_ARM_BRANCH24T, IMAGE_REL_ARM_BLX23T all
958 // perform a 4 byte adjustment to the relocation. Relative branches are
959 // offset by 4 on ARM, however, because there is no RELA relocations, all
960 // branches are offset by 4.
961 FixedValue = FixedValue + 4;
962 break;
963 }
964 }
965
966 // The fixed value never makes sense for section indices, ignore it.
967 if (Fixup.getKind() == FK_SecRel_2)
968 FixedValue = 0;
969
970 if (OWriter.TargetObjectWriter->recordRelocation(Fixup))
971 Sec->Relocations.push_back(Reloc);
972}
973
974static std::time_t getTime() {
975 std::time_t Now = time(nullptr);
976 if (Now < 0 || !isUInt<32>(Now))
977 return UINT32_MAX;
978 return Now;
979}
980
982 uint64_t StartOffset = W.OS.tell();
983
984 if (Sections.size() > INT32_MAX)
986 "PE COFF object files can't have more than 2147483647 sections");
987
988 UseBigObj = Sections.size() > COFF::MaxNumberOfSections16;
989 Header.NumberOfSections = Sections.size();
990 Header.NumberOfSymbols = 0;
991
992 setWeakDefaultNames();
993 assignSectionNumbers();
994 if (Mode != DwoOnly)
995 createFileSymbols(Asm);
996
997 for (auto &Symbol : Symbols) {
998 // Update section number & offset for symbols that have them.
999 if (Symbol->Section)
1000 Symbol->Data.SectionNumber = Symbol->Section->Number;
1001 Symbol->setIndex(Header.NumberOfSymbols++);
1002 // Update auxiliary symbol info.
1003 Symbol->Data.NumberOfAuxSymbols = Symbol->Aux.size();
1004 Header.NumberOfSymbols += Symbol->Data.NumberOfAuxSymbols;
1005 }
1006
1007 // Build string table.
1008 for (const auto &S : Sections)
1009 if (S->Name.size() > COFF::NameSize)
1010 Strings.add(S->Name);
1011 for (const auto &S : Symbols)
1012 if (S->Name.size() > COFF::NameSize)
1013 Strings.add(S->Name);
1014 Strings.finalize();
1015
1016 // Set names.
1017 for (const auto &S : Sections)
1018 SetSectionName(*S);
1019 for (auto &S : Symbols)
1020 SetSymbolName(*S);
1021
1022 // Fixup weak external references.
1023 for (auto &Symbol : Symbols) {
1024 if (Symbol->Other) {
1025 assert(Symbol->getIndex() != -1);
1026 assert(Symbol->Aux.size() == 1 && "Symbol must contain one aux symbol!");
1027 assert(Symbol->Aux[0].AuxType == ATWeakExternal &&
1028 "Symbol's aux symbol must be a Weak External!");
1029 Symbol->Aux[0].Aux.WeakExternal.TagIndex = Symbol->Other->getIndex();
1030 }
1031 }
1032
1033 // Fixup associative COMDAT sections.
1034 for (auto &Section : Sections) {
1035 if (Section->Symbol->Aux[0].Aux.SectionDefinition.Selection !=
1037 continue;
1038
1039 const MCSectionCOFF &MCSec = *Section->MCSection;
1040 const MCSymbol *AssocMCSym = MCSec.getCOMDATSymbol();
1041 assert(AssocMCSym);
1042
1043 // It's an error to try to associate with an undefined symbol or a symbol
1044 // without a section.
1045 if (!AssocMCSym->isInSection()) {
1046 Asm.getContext().reportError(
1047 SMLoc(), Twine("cannot make section ") + MCSec.getName() +
1048 Twine(" associative with sectionless symbol ") +
1049 AssocMCSym->getName());
1050 continue;
1051 }
1052
1053 const auto *AssocMCSec = cast<MCSectionCOFF>(&AssocMCSym->getSection());
1054 assert(SectionMap.count(AssocMCSec));
1055 COFFSection *AssocSec = SectionMap[AssocMCSec];
1056
1057 // Skip this section if the associated section is unused.
1058 if (AssocSec->Number == -1)
1059 continue;
1060
1061 Section->Symbol->Aux[0].Aux.SectionDefinition.Number = AssocSec->Number;
1062 }
1063
1064 // Create the contents of the .llvm_addrsig section.
1065 if (Mode != DwoOnly && OWriter.getEmitAddrsigSection()) {
1066 auto *Sec = Asm.getContext().getCOFFSection(
1067 ".llvm_addrsig", COFF::IMAGE_SCN_LNK_REMOVE);
1068 auto *Frag = cast<MCDataFragment>(Sec->curFragList()->Head);
1069 raw_svector_ostream OS(Frag->getContents());
1070 for (const MCSymbol *S : OWriter.AddrsigSyms) {
1071 if (!S->isRegistered())
1072 continue;
1073 if (!S->isTemporary()) {
1074 encodeULEB128(S->getIndex(), OS);
1075 continue;
1076 }
1077
1078 MCSection *TargetSection = &S->getSection();
1079 assert(SectionMap.contains(TargetSection) &&
1080 "Section must already have been defined in "
1081 "executePostLayoutBinding!");
1082 encodeULEB128(SectionMap[TargetSection]->Symbol->getIndex(), OS);
1083 }
1084 }
1085
1086 // Create the contents of the .llvm.call-graph-profile section.
1087 if (Mode != DwoOnly && !Asm.CGProfile.empty()) {
1088 auto *Sec = Asm.getContext().getCOFFSection(
1089 ".llvm.call-graph-profile", COFF::IMAGE_SCN_LNK_REMOVE);
1090 auto *Frag = cast<MCDataFragment>(Sec->curFragList()->Head);
1091 raw_svector_ostream OS(Frag->getContents());
1092 for (const MCAssembler::CGProfileEntry &CGPE : Asm.CGProfile) {
1093 uint32_t FromIndex = CGPE.From->getSymbol().getIndex();
1094 uint32_t ToIndex = CGPE.To->getSymbol().getIndex();
1095 support::endian::write(OS, FromIndex, W.Endian);
1096 support::endian::write(OS, ToIndex, W.Endian);
1098 }
1099 }
1100
1101 assignFileOffsets(Asm);
1102
1103 // MS LINK expects to be able to use this timestamp to implement their
1104 // /INCREMENTAL feature.
1105 if (OWriter.IncrementalLinkerCompatible) {
1106 Header.TimeDateStamp = getTime();
1107 } else {
1108 // Have deterministic output if /INCREMENTAL isn't needed. Also matches GNU.
1109 Header.TimeDateStamp = 0;
1110 }
1111
1112 // Write it all to disk...
1113 WriteFileHeader(Header);
1114 writeSectionHeaders();
1115
1116#ifndef NDEBUG
1117 sections::iterator I = Sections.begin();
1118 sections::iterator IE = Sections.end();
1119 auto J = Asm.begin();
1120 auto JE = Asm.end();
1121 for (; I != IE && J != JE; ++I, ++J) {
1122 while (J != JE && ((Mode == NonDwoOnly && isDwoSection(*J)) ||
1123 (Mode == DwoOnly && !isDwoSection(*J))))
1124 ++J;
1125 assert(J != JE && (**I).MCSection == &*J && "Wrong bound MCSection");
1126 }
1127#endif
1128
1129 // Write section contents.
1130 for (std::unique_ptr<COFFSection> &Sec : Sections)
1131 writeSection(Asm, *Sec);
1132
1133 assert(W.OS.tell() == Header.PointerToSymbolTable &&
1134 "Header::PointerToSymbolTable is insane!");
1135
1136 // Write a symbol table.
1137 for (auto &Symbol : Symbols)
1138 if (Symbol->getIndex() != -1)
1139 WriteSymbol(*Symbol);
1140
1141 // Write a string table, which completes the entire COFF file.
1142 Strings.write(W.OS);
1143
1144 return W.OS.tell() - StartOffset;
1145}
1146
1147//------------------------------------------------------------------------------
1148// WinCOFFObjectWriter class implementation
1149
1150////////////////////////////////////////////////////////////////////////////////
1151// MCObjectWriter interface implementations
1152
1154 IncrementalLinkerCompatible = false;
1155 ObjWriter->reset();
1156 if (DwoWriter)
1157 DwoWriter->reset();
1159}
1160
1162 const MCAssembler &Asm, const MCSymbol &SymA, const MCFragment &FB,
1163 bool InSet, bool IsPCRel) const {
1164 // Don't drop relocations between functions, even if they are in the same text
1165 // section. Multiple Visual C++ linker features depend on having the
1166 // relocations present. The /INCREMENTAL flag will cause these relocations to
1167 // point to thunks, and the /GUARD:CF flag assumes that it can use relocations
1168 // to approximate the set of all address taken functions. LLD's implementation
1169 // of /GUARD:CF also relies on the existance of these relocations.
1170 uint16_t Type = cast<MCSymbolCOFF>(SymA).getType();
1172 return false;
1173 return &SymA.getSection() == FB.getParent();
1174}
1175
1177 ObjWriter->executePostLayoutBinding(Asm);
1178 if (DwoWriter)
1179 DwoWriter->executePostLayoutBinding(Asm);
1180}
1181
1183 const MCFragment *Fragment,
1184 const MCFixup &Fixup, MCValue Target,
1185 uint64_t &FixedValue) {
1186 assert(!isDwoSection(*Fragment->getParent()) &&
1187 "No relocation in Dwo sections");
1188 ObjWriter->recordRelocation(Asm, Fragment, Fixup, Target, FixedValue);
1189}
1190
1192 uint64_t TotalSize = ObjWriter->writeObject(Asm);
1193 if (DwoWriter)
1194 TotalSize += DwoWriter->writeObject(Asm);
1195 return TotalSize;
1196}
1197
1199 : Machine(Machine_) {}
1200
1201// Pin the vtable to this file.
1202void MCWinCOFFObjectTargetWriter::anchor() {}
1203
1204//------------------------------------------------------------------------------
1205// WinCOFFObjectWriter factory function
1206
1207std::unique_ptr<MCObjectWriter> llvm::createWinCOFFObjectWriter(
1208 std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS) {
1209 return std::make_unique<WinCOFFObjectWriter>(std::move(MOTW), OS);
1210}
1211
1212std::unique_ptr<MCObjectWriter> llvm::createWinCOFFDwoObjectWriter(
1213 std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS,
1214 raw_pwrite_stream &DwoOS) {
1215 return std::make_unique<WinCOFFObjectWriter>(std::move(MOTW), OS, DwoOS);
1216}
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
static GCRegistry::Add< ErlangGC > A("erlang", "erlang-compatible garbage collector")
COFFYAML::AuxSymbolType AuxType
Definition: COFFYAML.cpp:353
COFF::MachineTypes Machine
Definition: COFFYAML.cpp:371
This file defines the DenseMap class.
This file defines the DenseSet and SmallDenseSet classes.
std::string Name
std::optional< std::vector< StOtherPiece > > Other
Definition: ELFYAML.cpp:1294
Symbol * Sym
Definition: ELF_riscv.cpp:479
#define I(x, y, z)
Definition: MD5.cpp:58
std::pair< uint64_t, uint64_t > Interval
PowerPC TLS Dynamic Call Fixup
uint32_t Number
Definition: Profile.cpp:47
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
static const char * name
Definition: SMEABIPass.cpp:50
This file contains some templates that are useful if you are working with the STL at all.
raw_pwrite_stream & OS
This file defines the SmallString class.
This file defines the SmallVector class.
static uint64_t getSymbolValue(const MCSymbol &Symbol, const MCAssembler &Asm)
static uint32_t getAlignment(const MCSectionCOFF &Sec)
static bool isAssociative(const COFFSection &Section)
static bool isDwoSection(const MCSection &Sec)
static std::time_t getTime()
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
size_type count(const_arg_type_t< KeyT > Val) const
Return 1 if the specified key is in the map, 0 otherwise.
Definition: DenseMap.h:151
bool contains(const_arg_type_t< KeyT > Val) const
Return true if the specified key is in the map, false otherwise.
Definition: DenseMap.h:145
Encode information on a single operation to perform on a byte sequence (e.g., an encoded instruction)...
Definition: MCFixup.h:71
MCSection * getParent() const
Definition: MCFragment.h:93
virtual void reset()
lifetime management
std::vector< const MCSymbol * > AddrsigSyms
This represents a section on Windows.
Definition: MCSectionCOFF.h:27
MCSymbol * getCOMDATSymbol() const
Definition: MCSectionCOFF.h:70
unsigned getCharacteristics() const
Definition: MCSectionCOFF.h:69
int getSelection() const
Definition: MCSectionCOFF.h:71
Instances of this class represent a uniqued identifier for a section in the current translation unit.
Definition: MCSection.h:36
Align getAlign() const
Definition: MCSection.h:144
StringRef getName() const
Definition: MCSection.h:128
bool empty() const
Definition: MCSection.h:179
MCSymbol * getBeginSymbol()
Definition: MCSection.h:133
uint16_t getType() const
Definition: MCSymbolCOFF.h:36
uint16_t getClass() const
Definition: MCSymbolCOFF.h:43
Represent a reference to a symbol from inside an expression.
Definition: MCExpr.h:188
const MCSymbol & getSymbol() const
Definition: MCExpr.h:406
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:41
bool isInSection() const
isInSection - Check if this symbol is defined in some section (i.e., it is defined but not absolute).
Definition: MCSymbol.h:254
StringRef getName() const
getName - Get the symbol name.
Definition: MCSymbol.h:205
bool isVariable() const
isVariable - Check if this is a variable symbol.
Definition: MCSymbol.h:300
bool isRegistered() const
Definition: MCSymbol.h:212
void setIndex(uint32_t Value) const
Set the (implementation defined) index.
Definition: MCSymbol.h:321
bool isUndefined(bool SetUsed=true) const
isUndefined - Check if this symbol undefined (i.e., implicitly defined).
Definition: MCSymbol.h:259
uint32_t getIndex() const
Get the (implementation defined) index.
Definition: MCSymbol.h:316
MCSection & getSection() const
Get the section associated with a defined, non-absolute symbol.
Definition: MCSymbol.h:269
bool isTemporary() const
isTemporary - Check if this is an assembler temporary symbol.
Definition: MCSymbol.h:222
bool isExternal() const
Definition: MCSymbol.h:407
MCFragment * getFragment(bool SetUsed=true) const
Definition: MCSymbol.h:397
This represents an "assembler immediate".
Definition: MCValue.h:36
Represents a location in source code.
Definition: SMLoc.h:23
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:26
size_t size() const
Definition: SmallVector.h:91
pointer data()
Return a pointer to the vector's buffer, even if empty().
Definition: SmallVector.h:299
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1209
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
bool ends_with(StringRef Suffix) const
Check if this string ends with the given Suffix.
Definition: StringRef.h:262
Utility for building string tables with deduplicated suffixes.
size_t getOffset(CachedHashStringRef S) const
Get the offest of a string in the string table.
void write(raw_ostream &OS) const
size_t add(CachedHashStringRef S)
Add a string to the builder.
void finalize()
Analyze the strings and build the final table.
Target - Wrapper for Target specific information.
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
LLVM Value Representation.
Definition: Value.h:74
void reset() override
lifetime management
void recordRelocation(MCAssembler &Asm, const MCFragment *Fragment, const MCFixup &Fixup, MCValue Target, uint64_t &FixedValue) override
Record a relocation entry.
WinCOFFObjectWriter(std::unique_ptr< MCWinCOFFObjectTargetWriter > MOTW, raw_pwrite_stream &OS)
bool isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, const MCSymbol &SymA, const MCFragment &FB, bool InSet, bool IsPCRel) const override
void executePostLayoutBinding(MCAssembler &Asm) override
Perform any late binding of symbols (for example, to assign symbol indices for use when generating re...
uint64_t writeObject(MCAssembler &Asm) override
Write the object file and returns the number of bytes written.
uint64_t writeObject(MCAssembler &Asm)
WinCOFFWriter(WinCOFFObjectWriter &OWriter, raw_pwrite_stream &OS, DwoMode Mode)
enum llvm::WinCOFFWriter::DwoMode Mode
void recordRelocation(MCAssembler &Asm, const MCFragment *Fragment, const MCFixup &Fixup, MCValue Target, uint64_t &FixedValue)
void executePostLayoutBinding(MCAssembler &Asm)
std::pair< iterator, bool > insert(const ValueT &V)
Definition: DenseSet.h:206
size_type count(const_arg_type_t< ValueT > V) const
Return 1 if the specified key is in the set, 0 otherwise.
Definition: DenseSet.h:97
raw_ostream & write_zeros(unsigned NumZeros)
write_zeros - Insert 'NumZeros' nulls.
uint64_t tell() const
tell - Return the current offset with the file.
Definition: raw_ostream.h:147
raw_ostream & write(unsigned char C)
An abstract base class for streams implementations that also support a pwrite operation.
Definition: raw_ostream.h:434
A raw_ostream that writes to an SmallVector or SmallString.
Definition: raw_ostream.h:691
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
@ NameSize
Definition: COFF.h:57
@ Header16Size
Definition: COFF.h:55
@ Symbol16Size
Definition: COFF.h:58
@ Header32Size
Definition: COFF.h:56
@ SectionSize
Definition: COFF.h:60
@ Symbol32Size
Definition: COFF.h:59
@ RelocationSize
Definition: COFF.h:61
@ IMAGE_FILE_MACHINE_UNKNOWN
Definition: COFF.h:95
@ IMAGE_FILE_MACHINE_AMD64
Definition: COFF.h:97
@ IMAGE_FILE_MACHINE_I386
Definition: COFF.h:104
@ IMAGE_FILE_MACHINE_ARMNT
Definition: COFF.h:99
@ IMAGE_SCN_ALIGN_64BYTES
Definition: COFF.h:320
@ IMAGE_SCN_ALIGN_128BYTES
Definition: COFF.h:321
@ IMAGE_SCN_ALIGN_256BYTES
Definition: COFF.h:322
@ IMAGE_SCN_ALIGN_1024BYTES
Definition: COFF.h:324
@ IMAGE_SCN_ALIGN_1BYTES
Definition: COFF.h:314
@ IMAGE_SCN_LNK_REMOVE
Definition: COFF.h:307
@ IMAGE_SCN_ALIGN_512BYTES
Definition: COFF.h:323
@ IMAGE_SCN_CNT_UNINITIALIZED_DATA
Definition: COFF.h:304
@ IMAGE_SCN_ALIGN_4096BYTES
Definition: COFF.h:326
@ IMAGE_SCN_ALIGN_8192BYTES
Definition: COFF.h:327
@ IMAGE_SCN_LNK_NRELOC_OVFL
Definition: COFF.h:329
@ IMAGE_SCN_ALIGN_16BYTES
Definition: COFF.h:318
@ IMAGE_SCN_LNK_COMDAT
Definition: COFF.h:308
@ IMAGE_SCN_ALIGN_8BYTES
Definition: COFF.h:317
@ IMAGE_SCN_ALIGN_4BYTES
Definition: COFF.h:316
@ IMAGE_SCN_ALIGN_32BYTES
Definition: COFF.h:319
@ IMAGE_SCN_ALIGN_2BYTES
Definition: COFF.h:315
@ IMAGE_SCN_ALIGN_2048BYTES
Definition: COFF.h:325
bool isAnyArm64(T Machine)
Definition: COFF.h:129
@ IMAGE_REL_ARM64_REL32
Definition: COFF.h:417
@ IMAGE_REL_AMD64_REL32
Definition: COFF.h:364
@ IMAGE_SYM_CLASS_EXTERNAL
External symbol.
Definition: COFF.h:223
@ IMAGE_SYM_CLASS_LABEL
Label.
Definition: COFF.h:227
@ IMAGE_SYM_CLASS_FILE
File name.
Definition: COFF.h:245
@ IMAGE_SYM_CLASS_NULL
No symbol.
Definition: COFF.h:221
@ IMAGE_SYM_CLASS_WEAK_EXTERNAL
Duplicate tag.
Definition: COFF.h:248
@ IMAGE_SYM_CLASS_STATIC
Static.
Definition: COFF.h:224
bool encodeSectionName(char *Out, uint64_t Offset)
Encode section name based on string table offset.
Definition: COFF.cpp:39
@ IMAGE_COMDAT_SELECT_ASSOCIATIVE
Definition: COFF.h:425
@ IMAGE_REL_ARM_MOV32A
Definition: COFF.h:391
@ IMAGE_REL_ARM_BRANCH20T
Definition: COFF.h:393
@ IMAGE_REL_ARM_BRANCH24
Definition: COFF.h:383
@ IMAGE_REL_ARM_ADDR32NB
Definition: COFF.h:382
@ IMAGE_REL_ARM_BRANCH11
Definition: COFF.h:384
@ IMAGE_REL_ARM_BLX24
Definition: COFF.h:386
@ IMAGE_REL_ARM_ADDR32
Definition: COFF.h:381
@ IMAGE_REL_ARM_MOV32T
Definition: COFF.h:392
@ IMAGE_REL_ARM_BRANCH24T
Definition: COFF.h:394
@ IMAGE_REL_ARM_ABSOLUTE
Definition: COFF.h:380
@ IMAGE_REL_ARM_REL32
Definition: COFF.h:388
@ IMAGE_REL_ARM_BLX23T
Definition: COFF.h:395
@ IMAGE_REL_ARM_SECREL
Definition: COFF.h:390
@ IMAGE_REL_ARM_SECTION
Definition: COFF.h:389
@ IMAGE_REL_ARM_BLX11
Definition: COFF.h:387
@ IMAGE_REL_ARM_TOKEN
Definition: COFF.h:385
const int32_t MaxNumberOfSections16
Definition: COFF.h:32
@ IMAGE_REL_I386_REL32
Definition: COFF.h:356
static const char BigObjMagic[]
Definition: COFF.h:37
@ IMAGE_SYM_DEBUG
Definition: COFF.h:211
@ IMAGE_SYM_ABSOLUTE
Definition: COFF.h:212
@ IMAGE_SYM_DTYPE_FUNCTION
A function that returns a base type.
Definition: COFF.h:275
@ SCT_COMPLEX_TYPE_SHIFT
Type is formed as (base + (derived << SCT_COMPLEX_TYPE_SHIFT))
Definition: COFF.h:279
void write32le(void *P, uint32_t V)
Definition: Endian.h:468
void write(void *memory, value_type value, endianness endian)
Write a value to memory with a particular endianness.
Definition: Endian.h:92
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:480
@ Length
Definition: DWP.cpp:480
auto size(R &&Range, std::enable_if_t< std::is_base_of< std::random_access_iterator_tag, typename std::iterator_traits< decltype(Range.begin())>::iterator_category >::value, void > *=nullptr)
Get the size of a range.
Definition: STLExtras.h:1680
void sort(IteratorTy Start, IteratorTy End)
Definition: STLExtras.h:1647
void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:167
std::unique_ptr< MCObjectWriter > createWinCOFFDwoObjectWriter(std::unique_ptr< MCWinCOFFObjectTargetWriter > MOTW, raw_pwrite_stream &OS, raw_pwrite_stream &DwoOS)
@ FK_SecRel_2
A two-byte section relative fixup.
Definition: MCFixup.h:41
std::unique_ptr< MCObjectWriter > createWinCOFFObjectWriter(std::unique_ptr< MCWinCOFFObjectTargetWriter > MOTW, raw_pwrite_stream &OS)
Construct a new Win COFF writer instance.
OutputIt move(R &&Range, OutputIt Out)
Provide wrappers to std::move which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1849
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
endianness
Definition: bit.h:70
Implement std::hash so that hash_code can be used in STL containers.
Definition: BitVector.h:858
#define N
uint64_t value() const
This is a hole in the type system and should not be abused.
Definition: Alignment.h:85
uint16_t Machine
Definition: COFF.h:65
uint32_t VirtualSize
Definition: COFF.h:286
uint32_t PointerToRelocations
Definition: COFF.h:290
uint16_t NumberOfLineNumbers
Definition: COFF.h:293
uint32_t PointerToRawData
Definition: COFF.h:289
uint32_t SizeOfRawData
Definition: COFF.h:288
uint32_t Characteristics
Definition: COFF.h:294
uint16_t NumberOfRelocations
Definition: COFF.h:292
char Name[NameSize]
Definition: COFF.h:285
uint32_t VirtualAddress
Definition: COFF.h:287
uint32_t PointerToLineNumbers
Definition: COFF.h:291
const MCSymbolRefExpr * From
Definition: MCAssembler.h:272
const MCSymbolRefExpr * To
Definition: MCAssembler.h:273
Adapter to write values to a stream in a particular byte order.
Definition: EndianStream.h:67
void write(ArrayRef< value_type > Val)
Definition: EndianStream.h:71