1 //===-- llvm/MC/WinCOFFObjectWriter.cpp -------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains an implementation of a Win32 COFF object file writer.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "WinCOFFObjectWriter"
16 #include "llvm/MC/MCObjectWriter.h"
17 #include "llvm/MC/MCSection.h"
18 #include "llvm/MC/MCContext.h"
19 #include "llvm/MC/MCSymbol.h"
20 #include "llvm/MC/MCExpr.h"
21 #include "llvm/MC/MCValue.h"
22 #include "llvm/MC/MCAssembler.h"
23 #include "llvm/MC/MCAsmLayout.h"
24 #include "llvm/MC/MCSectionCOFF.h"
26 #include "llvm/ADT/DenseMap.h"
27 #include "llvm/ADT/StringMap.h"
28 #include "llvm/ADT/StringRef.h"
30 #include "llvm/Support/COFF.h"
31 #include "llvm/Support/Debug.h"
32 #include "llvm/Support/ErrorHandling.h"
34 #include "llvm/Support/TimeValue.h"
36 #include "../Target/X86/X86FixupKinds.h"
43 typedef llvm::SmallString<COFF::NameSize> name;
54 AuxiliaryType AuxType;
65 typedef llvm::SmallVector<AuxSymbol, 1> AuxiliarySymbols;
74 MCSymbolData const *MCData;
76 COFFSymbol(llvm::StringRef name);
78 void set_name_offset(uint32_t Offset);
80 bool should_keep() const;
83 // This class contains staging data for a COFF relocation entry.
84 struct COFFRelocation {
85 COFF::relocation Data;
88 COFFRelocation() : Symb(NULL) {}
89 static size_t size() { return COFF::RelocationSize; }
92 typedef std::vector<COFFRelocation> relocations;
100 MCSectionData const *MCData;
102 relocations Relocations;
104 COFFSection(llvm::StringRef name);
105 static size_t size();
108 // This class holds the COFF string table.
110 typedef llvm::StringMap<size_t> map;
113 void update_length();
115 std::vector<char> Data;
119 size_t insert(llvm::StringRef String);
122 class WinCOFFObjectWriter : public MCObjectWriter {
125 typedef std::vector<COFFSymbol*> symbols;
126 typedef std::vector<COFFSection*> sections;
128 typedef DenseMap<MCSymbol const *, COFFSymbol *> symbol_map;
129 typedef DenseMap<MCSection const *, COFFSection *> section_map;
131 // Root level file contents.
138 // Maps used during object file creation.
139 section_map SectionMap;
140 symbol_map SymbolMap;
142 WinCOFFObjectWriter(raw_ostream &OS, bool is64Bit);
143 ~WinCOFFObjectWriter();
145 COFFSymbol *createSymbol(StringRef Name);
146 COFFSymbol *GetOrCreateCOFFSymbol(const MCSymbol * Symbol);
147 COFFSection *createSection(StringRef Name);
149 template <typename object_t, typename list_t>
150 object_t *createCOFFEntity(llvm::StringRef Name, list_t &List);
152 void DefineSection(MCSectionData const &SectionData);
153 void DefineSymbol(MCSymbolData const &SymbolData, MCAssembler &Assembler);
155 void MakeSymbolReal(COFFSymbol &S, size_t Index);
156 void MakeSectionReal(COFFSection &S, size_t Number);
158 bool ExportSection(COFFSection const *S);
159 bool ExportSymbol(MCSymbolData const &SymbolData, MCAssembler &Asm);
161 bool IsPhysicalSection(COFFSection *S);
163 // Entity writing methods.
165 void WriteFileHeader(const COFF::header &Header);
166 void WriteSymbol(const COFFSymbol *S);
167 void WriteAuxiliarySymbols(const COFFSymbol::AuxiliarySymbols &S);
168 void WriteSectionHeader(const COFF::section &S);
169 void WriteRelocation(const COFF::relocation &R);
171 // MCObjectWriter interface implementation.
173 void ExecutePostLayoutBinding(MCAssembler &Asm, const MCAsmLayout &Layout);
175 void RecordRelocation(const MCAssembler &Asm,
176 const MCAsmLayout &Layout,
177 const MCFragment *Fragment,
178 const MCFixup &Fixup,
180 uint64_t &FixedValue);
183 IsSymbolRefDifferenceFullyResolved(const MCAssembler &Asm,
184 const MCSymbolRefExpr *A,
185 const MCSymbolRefExpr *B) const {
186 // FIXME: Implement this!
190 virtual bool IsFixupFullyResolved(const MCAssembler &Asm,
191 const MCValue Target,
193 const MCFragment *DF) const;
195 void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout);
199 static inline void write_uint32_le(void *Data, uint32_t const &Value) {
200 uint8_t *Ptr = reinterpret_cast<uint8_t *>(Data);
201 Ptr[0] = (Value & 0x000000FF) >> 0;
202 Ptr[1] = (Value & 0x0000FF00) >> 8;
203 Ptr[2] = (Value & 0x00FF0000) >> 16;
204 Ptr[3] = (Value & 0xFF000000) >> 24;
207 static inline void write_uint16_le(void *Data, uint16_t const &Value) {
208 uint8_t *Ptr = reinterpret_cast<uint8_t *>(Data);
209 Ptr[0] = (Value & 0x00FF) >> 0;
210 Ptr[1] = (Value & 0xFF00) >> 8;
213 static inline void write_uint8_le(void *Data, uint8_t const &Value) {
214 uint8_t *Ptr = reinterpret_cast<uint8_t *>(Data);
215 Ptr[0] = (Value & 0xFF) >> 0;
218 //------------------------------------------------------------------------------
219 // Symbol class implementation
221 COFFSymbol::COFFSymbol(llvm::StringRef name)
222 : Name(name.begin(), name.end())
227 memset(&Data, 0, sizeof(Data));
230 size_t COFFSymbol::size() const {
231 return COFF::SymbolSize + (Data.NumberOfAuxSymbols * COFF::SymbolSize);
234 // In the case that the name does not fit within 8 bytes, the offset
235 // into the string table is stored in the last 4 bytes instead, leaving
236 // the first 4 bytes as 0.
237 void COFFSymbol::set_name_offset(uint32_t Offset) {
238 write_uint32_le(Data.Name + 0, 0);
239 write_uint32_le(Data.Name + 4, Offset);
242 /// logic to decide if the symbol should be reported in the symbol table
243 bool COFFSymbol::should_keep() const {
244 // no section means its external, keep it
248 // if it has relocations pointing at it, keep it
249 if (Relocations > 0) {
250 assert(Section->Number != -1 && "Sections with relocations must be real!");
254 // if the section its in is being droped, drop it
255 if (Section->Number == -1)
258 // if it is the section symbol, keep it
259 if (Section->Symbol == this)
262 // if its temporary, drop it
263 if (MCData && MCData->getSymbol().isTemporary())
266 // otherwise, keep it
270 //------------------------------------------------------------------------------
271 // Section class implementation
273 COFFSection::COFFSection(llvm::StringRef name)
277 memset(&Header, 0, sizeof(Header));
280 size_t COFFSection::size() {
281 return COFF::SectionSize;
284 //------------------------------------------------------------------------------
285 // StringTable class implementation
287 /// Write the length of the string table into Data.
288 /// The length of the string table includes uint32 length header.
289 void StringTable::update_length() {
290 write_uint32_le(&Data.front(), Data.size());
293 StringTable::StringTable() {
294 // The string table data begins with the length of the entire string table
295 // including the length header. Allocate space for this header.
299 size_t StringTable::size() const {
303 /// Add String to the table iff it is not already there.
304 /// @returns the index into the string table where the string is now located.
305 size_t StringTable::insert(llvm::StringRef String) {
306 map::iterator i = Map.find(String);
311 size_t Offset = Data.size();
313 // Insert string data into string table.
314 Data.insert(Data.end(), String.begin(), String.end());
315 Data.push_back('\0');
317 // Put a reference to it in the map.
318 Map[String] = Offset;
320 // Update the internal length field.
326 //------------------------------------------------------------------------------
327 // WinCOFFObjectWriter class implementation
329 WinCOFFObjectWriter::WinCOFFObjectWriter(raw_ostream &OS, bool is64Bit)
330 : MCObjectWriter(OS, true)
332 memset(&Header, 0, sizeof(Header));
334 Is64Bit ? Header.Machine = COFF::IMAGE_FILE_MACHINE_AMD64
335 : Header.Machine = COFF::IMAGE_FILE_MACHINE_I386;
338 WinCOFFObjectWriter::~WinCOFFObjectWriter() {
339 for (symbols::iterator I = Symbols.begin(), E = Symbols.end(); I != E; ++I)
341 for (sections::iterator I = Sections.begin(), E = Sections.end(); I != E; ++I)
345 COFFSymbol *WinCOFFObjectWriter::createSymbol(StringRef Name) {
346 return createCOFFEntity<COFFSymbol>(Name, Symbols);
349 COFFSymbol *WinCOFFObjectWriter::GetOrCreateCOFFSymbol(const MCSymbol * Symbol){
350 symbol_map::iterator i = SymbolMap.find(Symbol);
351 if (i != SymbolMap.end())
353 COFFSymbol *RetSymbol
354 = createCOFFEntity<COFFSymbol>(Symbol->getName(), Symbols);
355 SymbolMap[Symbol] = RetSymbol;
359 COFFSection *WinCOFFObjectWriter::createSection(llvm::StringRef Name) {
360 return createCOFFEntity<COFFSection>(Name, Sections);
363 /// A template used to lookup or create a symbol/section, and initialize it if
365 template <typename object_t, typename list_t>
366 object_t *WinCOFFObjectWriter::createCOFFEntity(llvm::StringRef Name,
368 object_t *Object = new object_t(Name);
370 List.push_back(Object);
375 /// This function takes a section data object from the assembler
376 /// and creates the associated COFF section staging object.
377 void WinCOFFObjectWriter::DefineSection(MCSectionData const &SectionData) {
378 assert(SectionData.getSection().getVariant() == MCSection::SV_COFF
379 && "Got non COFF section in the COFF backend!");
380 // FIXME: Not sure how to verify this (at least in a debug build).
381 MCSectionCOFF const &Sec =
382 static_cast<MCSectionCOFF const &>(SectionData.getSection());
384 COFFSection *coff_section = createSection(Sec.getSectionName());
385 COFFSymbol *coff_symbol = createSymbol(Sec.getSectionName());
387 coff_section->Symbol = coff_symbol;
388 coff_symbol->Section = coff_section;
389 coff_symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_STATIC;
391 // In this case the auxiliary symbol is a Section Definition.
392 coff_symbol->Aux.resize(1);
393 memset(&coff_symbol->Aux[0], 0, sizeof(coff_symbol->Aux[0]));
394 coff_symbol->Aux[0].AuxType = ATSectionDefinition;
395 coff_symbol->Aux[0].Aux.SectionDefinition.Selection = Sec.getSelection();
397 coff_section->Header.Characteristics = Sec.getCharacteristics();
399 uint32_t &Characteristics = coff_section->Header.Characteristics;
400 switch (SectionData.getAlignment()) {
401 case 1: Characteristics |= COFF::IMAGE_SCN_ALIGN_1BYTES; break;
402 case 2: Characteristics |= COFF::IMAGE_SCN_ALIGN_2BYTES; break;
403 case 4: Characteristics |= COFF::IMAGE_SCN_ALIGN_4BYTES; break;
404 case 8: Characteristics |= COFF::IMAGE_SCN_ALIGN_8BYTES; break;
405 case 16: Characteristics |= COFF::IMAGE_SCN_ALIGN_16BYTES; break;
406 case 32: Characteristics |= COFF::IMAGE_SCN_ALIGN_32BYTES; break;
407 case 64: Characteristics |= COFF::IMAGE_SCN_ALIGN_64BYTES; break;
408 case 128: Characteristics |= COFF::IMAGE_SCN_ALIGN_128BYTES; break;
409 case 256: Characteristics |= COFF::IMAGE_SCN_ALIGN_256BYTES; break;
410 case 512: Characteristics |= COFF::IMAGE_SCN_ALIGN_512BYTES; break;
411 case 1024: Characteristics |= COFF::IMAGE_SCN_ALIGN_1024BYTES; break;
412 case 2048: Characteristics |= COFF::IMAGE_SCN_ALIGN_2048BYTES; break;
413 case 4096: Characteristics |= COFF::IMAGE_SCN_ALIGN_4096BYTES; break;
414 case 8192: Characteristics |= COFF::IMAGE_SCN_ALIGN_8192BYTES; break;
416 llvm_unreachable("unsupported section alignment");
419 // Bind internal COFF section to MC section.
420 coff_section->MCData = &SectionData;
421 SectionMap[&SectionData.getSection()] = coff_section;
424 /// This function takes a section data object from the assembler
425 /// and creates the associated COFF symbol staging object.
426 void WinCOFFObjectWriter::DefineSymbol(MCSymbolData const &SymbolData,
427 MCAssembler &Assembler) {
428 COFFSymbol *coff_symbol = GetOrCreateCOFFSymbol(&SymbolData.getSymbol());
430 coff_symbol->Data.Type = (SymbolData.getFlags() & 0x0000FFFF) >> 0;
431 coff_symbol->Data.StorageClass = (SymbolData.getFlags() & 0x00FF0000) >> 16;
433 if (SymbolData.getFlags() & COFF::SF_WeakExternal) {
434 coff_symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL;
436 if (SymbolData.getSymbol().isVariable()) {
437 coff_symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL;
438 const MCExpr *Value = SymbolData.getSymbol().getVariableValue();
440 // FIXME: This assert message isn't very good.
441 assert(Value->getKind() == MCExpr::SymbolRef &&
442 "Value must be a SymbolRef!");
444 const MCSymbolRefExpr *SymbolRef =
445 static_cast<const MCSymbolRefExpr *>(Value);
446 coff_symbol->Other = GetOrCreateCOFFSymbol(&SymbolRef->getSymbol());
448 std::string WeakName = std::string(".weak.")
449 + SymbolData.getSymbol().getName().str()
451 COFFSymbol *WeakDefault = createSymbol(WeakName);
452 WeakDefault->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE;
453 WeakDefault->Data.StorageClass = COFF::IMAGE_SYM_CLASS_EXTERNAL;
454 WeakDefault->Data.Type = 0;
455 WeakDefault->Data.Value = 0;
456 coff_symbol->Other = WeakDefault;
459 // Setup the Weak External auxiliary symbol.
460 coff_symbol->Aux.resize(1);
461 memset(&coff_symbol->Aux[0], 0, sizeof(coff_symbol->Aux[0]));
462 coff_symbol->Aux[0].AuxType = ATWeakExternal;
463 coff_symbol->Aux[0].Aux.WeakExternal.TagIndex = 0;
464 coff_symbol->Aux[0].Aux.WeakExternal.Characteristics =
465 COFF::IMAGE_WEAK_EXTERN_SEARCH_LIBRARY;
468 // If no storage class was specified in the streamer, define it here.
469 if (coff_symbol->Data.StorageClass == 0) {
470 bool external = SymbolData.isExternal() || (SymbolData.Fragment == NULL);
472 coff_symbol->Data.StorageClass =
473 external ? COFF::IMAGE_SYM_CLASS_EXTERNAL : COFF::IMAGE_SYM_CLASS_STATIC;
476 if (SymbolData.Fragment != NULL)
477 coff_symbol->Section =
478 SectionMap[&SymbolData.Fragment->getParent()->getSection()];
480 // Bind internal COFF symbol to MC symbol.
481 coff_symbol->MCData = &SymbolData;
482 SymbolMap[&SymbolData.getSymbol()] = coff_symbol;
485 /// making a section real involves assigned it a number and putting
486 /// name into the string table if needed
487 void WinCOFFObjectWriter::MakeSectionReal(COFFSection &S, size_t Number) {
488 if (S.Name.size() > COFF::NameSize) {
489 size_t StringTableEntry = Strings.insert(S.Name.c_str());
491 // FIXME: Why is this number 999999? This number is never mentioned in the
492 // spec. I'm assuming this is due to the printed value needing to fit into
493 // the S.Header.Name field. In which case why not 9999999 (7 9's instead of
494 // 6)? The spec does not state if this entry should be null terminated in
495 // this case, and thus this seems to be the best way to do it. I think I
496 // just solved my own FIXME...
497 if (StringTableEntry > 999999)
498 report_fatal_error("COFF string table is greater than 999999 bytes.");
500 std::sprintf(S.Header.Name, "/%d", unsigned(StringTableEntry));
502 std::memcpy(S.Header.Name, S.Name.c_str(), S.Name.size());
505 S.Symbol->Data.SectionNumber = S.Number;
506 S.Symbol->Aux[0].Aux.SectionDefinition.Number = S.Number;
509 void WinCOFFObjectWriter::MakeSymbolReal(COFFSymbol &S, size_t Index) {
510 if (S.Name.size() > COFF::NameSize) {
511 size_t StringTableEntry = Strings.insert(S.Name.c_str());
513 S.set_name_offset(StringTableEntry);
515 std::memcpy(S.Data.Name, S.Name.c_str(), S.Name.size());
519 bool WinCOFFObjectWriter::ExportSection(COFFSection const *S) {
520 return !S->MCData->getFragmentList().empty();
523 bool WinCOFFObjectWriter::ExportSymbol(MCSymbolData const &SymbolData,
525 // This doesn't seem to be right. Strings referred to from the .data section
526 // need symbols so they can be linked to code in the .text section right?
528 // return Asm.isSymbolLinkerVisible (&SymbolData);
530 // For now, all non-variable symbols are exported,
531 // the linker will sort the rest out for us.
532 return SymbolData.isExternal() || !SymbolData.getSymbol().isVariable();
535 bool WinCOFFObjectWriter::IsPhysicalSection(COFFSection *S) {
536 return (S->Header.Characteristics
537 & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA) == 0;
540 //------------------------------------------------------------------------------
541 // entity writing methods
543 void WinCOFFObjectWriter::WriteFileHeader(const COFF::header &Header) {
544 WriteLE16(Header.Machine);
545 WriteLE16(Header.NumberOfSections);
546 WriteLE32(Header.TimeDateStamp);
547 WriteLE32(Header.PointerToSymbolTable);
548 WriteLE32(Header.NumberOfSymbols);
549 WriteLE16(Header.SizeOfOptionalHeader);
550 WriteLE16(Header.Characteristics);
553 void WinCOFFObjectWriter::WriteSymbol(const COFFSymbol *S) {
554 WriteBytes(StringRef(S->Data.Name, COFF::NameSize));
555 WriteLE32(S->Data.Value);
556 WriteLE16(S->Data.SectionNumber);
557 WriteLE16(S->Data.Type);
558 Write8(S->Data.StorageClass);
559 Write8(S->Data.NumberOfAuxSymbols);
560 WriteAuxiliarySymbols(S->Aux);
563 void WinCOFFObjectWriter::WriteAuxiliarySymbols(
564 const COFFSymbol::AuxiliarySymbols &S) {
565 for(COFFSymbol::AuxiliarySymbols::const_iterator i = S.begin(), e = S.end();
568 case ATFunctionDefinition:
569 WriteLE32(i->Aux.FunctionDefinition.TagIndex);
570 WriteLE32(i->Aux.FunctionDefinition.TotalSize);
571 WriteLE32(i->Aux.FunctionDefinition.PointerToLinenumber);
572 WriteLE32(i->Aux.FunctionDefinition.PointerToNextFunction);
573 WriteZeros(sizeof(i->Aux.FunctionDefinition.unused));
575 case ATbfAndefSymbol:
576 WriteZeros(sizeof(i->Aux.bfAndefSymbol.unused1));
577 WriteLE16(i->Aux.bfAndefSymbol.Linenumber);
578 WriteZeros(sizeof(i->Aux.bfAndefSymbol.unused2));
579 WriteLE32(i->Aux.bfAndefSymbol.PointerToNextFunction);
580 WriteZeros(sizeof(i->Aux.bfAndefSymbol.unused3));
583 WriteLE32(i->Aux.WeakExternal.TagIndex);
584 WriteLE32(i->Aux.WeakExternal.Characteristics);
585 WriteZeros(sizeof(i->Aux.WeakExternal.unused));
588 WriteBytes(StringRef(reinterpret_cast<const char *>(i->Aux.File.FileName),
589 sizeof(i->Aux.File.FileName)));
591 case ATSectionDefinition:
592 WriteLE32(i->Aux.SectionDefinition.Length);
593 WriteLE16(i->Aux.SectionDefinition.NumberOfRelocations);
594 WriteLE16(i->Aux.SectionDefinition.NumberOfLinenumbers);
595 WriteLE32(i->Aux.SectionDefinition.CheckSum);
596 WriteLE16(i->Aux.SectionDefinition.Number);
597 Write8(i->Aux.SectionDefinition.Selection);
598 WriteZeros(sizeof(i->Aux.SectionDefinition.unused));
604 void WinCOFFObjectWriter::WriteSectionHeader(const COFF::section &S) {
605 WriteBytes(StringRef(S.Name, COFF::NameSize));
607 WriteLE32(S.VirtualSize);
608 WriteLE32(S.VirtualAddress);
609 WriteLE32(S.SizeOfRawData);
610 WriteLE32(S.PointerToRawData);
611 WriteLE32(S.PointerToRelocations);
612 WriteLE32(S.PointerToLineNumbers);
613 WriteLE16(S.NumberOfRelocations);
614 WriteLE16(S.NumberOfLineNumbers);
615 WriteLE32(S.Characteristics);
618 void WinCOFFObjectWriter::WriteRelocation(const COFF::relocation &R) {
619 WriteLE32(R.VirtualAddress);
620 WriteLE32(R.SymbolTableIndex);
624 ////////////////////////////////////////////////////////////////////////////////
625 // MCObjectWriter interface implementations
627 void WinCOFFObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm,
628 const MCAsmLayout &Layout) {
629 // "Define" each section & symbol. This creates section & symbol
630 // entries in the staging area.
632 for (MCAssembler::const_iterator i = Asm.begin(), e = Asm.end(); i != e; i++)
635 for (MCAssembler::const_symbol_iterator i = Asm.symbol_begin(),
636 e = Asm.symbol_end(); i != e; i++) {
637 if (ExportSymbol(*i, Asm))
638 DefineSymbol(*i, Asm);
642 void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm,
643 const MCAsmLayout &Layout,
644 const MCFragment *Fragment,
645 const MCFixup &Fixup,
647 uint64_t &FixedValue) {
648 assert(Target.getSymA() != NULL && "Relocation must reference a symbol!");
650 const MCSymbol *A = &Target.getSymA()->getSymbol();
651 MCSymbolData &A_SD = Asm.getSymbolData(*A);
653 MCSectionData const *SectionData = Fragment->getParent();
655 // Mark this symbol as requiring an entry in the symbol table.
656 assert(SectionMap.find(&SectionData->getSection()) != SectionMap.end() &&
657 "Section must already have been defined in ExecutePostLayoutBinding!");
658 assert(SymbolMap.find(&A_SD.getSymbol()) != SymbolMap.end() &&
659 "Symbol must already have been defined in ExecutePostLayoutBinding!");
661 COFFSection *coff_section = SectionMap[&SectionData->getSection()];
662 COFFSymbol *coff_symbol = SymbolMap[&A_SD.getSymbol()];
664 if (Target.getSymB()) {
665 if (&Target.getSymA()->getSymbol().getSection()
666 != &Target.getSymB()->getSymbol().getSection()) {
667 llvm_unreachable("Symbol relative relocations are only allowed between "
668 "symbols in the same section");
670 const MCSymbol *B = &Target.getSymB()->getSymbol();
671 MCSymbolData &B_SD = Asm.getSymbolData(*B);
673 FixedValue = Layout.getSymbolOffset(&A_SD) - Layout.getSymbolOffset(&B_SD);
675 // In the case where we have SymbA and SymB, we just need to store the delta
676 // between the two symbols. Update FixedValue to account for the delta, and
677 // skip recording the relocation.
680 FixedValue = Target.getConstant();
683 COFFRelocation Reloc;
685 Reloc.Data.SymbolTableIndex = 0;
686 Reloc.Data.VirtualAddress = Layout.getFragmentOffset(Fragment);
688 // Turn relocations for temporary symbols into section relocations.
689 if (coff_symbol->MCData->getSymbol().isTemporary()) {
690 Reloc.Symb = coff_symbol->Section->Symbol;
691 FixedValue += Layout.getFragmentOffset(coff_symbol->MCData->Fragment)
692 + coff_symbol->MCData->getOffset();
694 Reloc.Symb = coff_symbol;
696 ++Reloc.Symb->Relocations;
698 Reloc.Data.VirtualAddress += Fixup.getOffset();
700 switch ((unsigned)Fixup.getKind()) {
702 case X86::reloc_riprel_4byte:
703 case X86::reloc_riprel_4byte_movq_load:
704 Reloc.Data.Type = Is64Bit ? COFF::IMAGE_REL_AMD64_REL32
705 : COFF::IMAGE_REL_I386_REL32;
706 // FIXME: Can anyone explain what this does other than adjust for the size
711 case X86::reloc_signed_4byte:
712 Reloc.Data.Type = Is64Bit ? COFF::IMAGE_REL_AMD64_ADDR32
713 : COFF::IMAGE_REL_I386_DIR32;
717 Reloc.Data.Type = COFF::IMAGE_REL_AMD64_ADDR64;
719 llvm_unreachable("unsupported relocation type");
722 llvm_unreachable("unsupported relocation type");
725 coff_section->Relocations.push_back(Reloc);
728 bool WinCOFFObjectWriter::IsFixupFullyResolved(const MCAssembler &Asm,
729 const MCValue Target,
731 const MCFragment *DF) const {
732 // If this is a PCrel relocation, find the section this fixup value is
734 const MCSection *BaseSection = 0;
736 BaseSection = &DF->getParent()->getSection();
740 const MCSection *SectionA = 0;
741 const MCSymbol *SymbolA = 0;
742 if (const MCSymbolRefExpr *A = Target.getSymA()) {
743 SymbolA = &A->getSymbol();
744 SectionA = &SymbolA->getSection();
747 const MCSection *SectionB = 0;
748 if (const MCSymbolRefExpr *B = Target.getSymB()) {
749 SectionB = &B->getSymbol().getSection();
753 return SectionA == SectionB;
755 return !SectionB && BaseSection == SectionA;
758 void WinCOFFObjectWriter::WriteObject(MCAssembler &Asm,
759 const MCAsmLayout &Layout) {
760 // Assign symbol and section indexes and offsets.
761 Header.NumberOfSections = 0;
763 for (sections::iterator i = Sections.begin(),
764 e = Sections.end(); i != e; i++) {
765 if (Layout.getSectionAddressSize((*i)->MCData) > 0) {
766 MakeSectionReal(**i, ++Header.NumberOfSections);
772 Header.NumberOfSymbols = 0;
774 for (symbols::iterator i = Symbols.begin(), e = Symbols.end(); i != e; i++) {
775 COFFSymbol *coff_symbol = *i;
776 MCSymbolData const *SymbolData = coff_symbol->MCData;
778 // Update section number & offset for symbols that have them.
779 if ((SymbolData != NULL) && (SymbolData->Fragment != NULL)) {
780 assert(coff_symbol->Section != NULL);
782 coff_symbol->Data.SectionNumber = coff_symbol->Section->Number;
783 coff_symbol->Data.Value = Layout.getFragmentOffset(SymbolData->Fragment)
784 + SymbolData->Offset;
787 if (coff_symbol->should_keep()) {
788 MakeSymbolReal(*coff_symbol, Header.NumberOfSymbols++);
790 // Update auxiliary symbol info.
791 coff_symbol->Data.NumberOfAuxSymbols = coff_symbol->Aux.size();
792 Header.NumberOfSymbols += coff_symbol->Data.NumberOfAuxSymbols;
794 coff_symbol->Index = -1;
797 // Fixup weak external references.
798 for (symbols::iterator i = Symbols.begin(), e = Symbols.end(); i != e; i++) {
799 COFFSymbol *coff_symbol = *i;
800 if (coff_symbol->Other != NULL) {
801 assert(coff_symbol->Index != -1);
802 assert(coff_symbol->Aux.size() == 1 &&
803 "Symbol must contain one aux symbol!");
804 assert(coff_symbol->Aux[0].AuxType == ATWeakExternal &&
805 "Symbol's aux symbol must be a Weak External!");
806 coff_symbol->Aux[0].Aux.WeakExternal.TagIndex = coff_symbol->Other->Index;
810 // Assign file offsets to COFF object file structures.
814 offset += COFF::HeaderSize;
815 offset += COFF::SectionSize * Header.NumberOfSections;
817 for (MCAssembler::const_iterator i = Asm.begin(),
820 COFFSection *Sec = SectionMap[&i->getSection()];
822 if (Sec->Number == -1)
825 Sec->Header.SizeOfRawData = Layout.getSectionAddressSize(i);
827 if (IsPhysicalSection(Sec)) {
828 Sec->Header.PointerToRawData = offset;
830 offset += Sec->Header.SizeOfRawData;
833 if (Sec->Relocations.size() > 0) {
834 Sec->Header.NumberOfRelocations = Sec->Relocations.size();
835 Sec->Header.PointerToRelocations = offset;
837 offset += COFF::RelocationSize * Sec->Relocations.size();
839 for (relocations::iterator cr = Sec->Relocations.begin(),
840 er = Sec->Relocations.end();
842 assert((*cr).Symb->Index != -1);
843 (*cr).Data.SymbolTableIndex = (*cr).Symb->Index;
847 assert(Sec->Symbol->Aux.size() == 1
848 && "Section's symbol must have one aux!");
849 AuxSymbol &Aux = Sec->Symbol->Aux[0];
850 assert(Aux.AuxType == ATSectionDefinition &&
851 "Section's symbol's aux symbol must be a Section Definition!");
852 Aux.Aux.SectionDefinition.Length = Sec->Header.SizeOfRawData;
853 Aux.Aux.SectionDefinition.NumberOfRelocations =
854 Sec->Header.NumberOfRelocations;
855 Aux.Aux.SectionDefinition.NumberOfLinenumbers =
856 Sec->Header.NumberOfLineNumbers;
859 Header.PointerToSymbolTable = offset;
861 Header.TimeDateStamp = sys::TimeValue::now().toEpochTime();
863 // Write it all to disk...
864 WriteFileHeader(Header);
867 sections::iterator i, ie;
868 MCAssembler::const_iterator j, je;
870 for (i = Sections.begin(), ie = Sections.end(); i != ie; i++)
871 if ((*i)->Number != -1)
872 WriteSectionHeader((*i)->Header);
874 for (i = Sections.begin(), ie = Sections.end(),
875 j = Asm.begin(), je = Asm.end();
876 (i != ie) && (j != je); ++i, ++j) {
878 if ((*i)->Number == -1)
881 if ((*i)->Header.PointerToRawData != 0) {
882 assert(OS.tell() == (*i)->Header.PointerToRawData &&
883 "Section::PointerToRawData is insane!");
885 Asm.WriteSectionData(j, Layout);
888 if ((*i)->Relocations.size() > 0) {
889 assert(OS.tell() == (*i)->Header.PointerToRelocations &&
890 "Section::PointerToRelocations is insane!");
892 for (relocations::const_iterator k = (*i)->Relocations.begin(),
893 ke = (*i)->Relocations.end();
895 WriteRelocation(k->Data);
898 assert((*i)->Header.PointerToRelocations == 0 &&
899 "Section::PointerToRelocations is insane!");
903 assert(OS.tell() == Header.PointerToSymbolTable &&
904 "Header::PointerToSymbolTable is insane!");
906 for (symbols::iterator i = Symbols.begin(), e = Symbols.end(); i != e; i++)
907 if ((*i)->Index != -1)
910 OS.write((char const *)&Strings.Data.front(), Strings.Data.size());
913 //------------------------------------------------------------------------------
914 // WinCOFFObjectWriter factory function
917 MCObjectWriter *createWinCOFFObjectWriter(raw_ostream &OS, bool is64Bit) {
918 return new WinCOFFObjectWriter(OS, is64Bit);