X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FWinCOFFObjectWriter.cpp;h=f251942161d81bc2801fc72d0433c655044e62cb;hb=c3d768d729e32c3c9d7a8ec593fc6e3fb4def019;hp=afc40a528d982d813bb9c46c9a98eddc9d9ec514;hpb=a69494ee5ec9fdbb38961dc71140629be9cbd601;p=oota-llvm.git diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp index afc40a528d9..f251942161d 100644 --- a/lib/MC/WinCOFFObjectWriter.cpp +++ b/lib/MC/WinCOFFObjectWriter.cpp @@ -11,34 +11,38 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "WinCOFFObjectWriter" - -#include "llvm/MC/MCObjectWriter.h" -#include "llvm/MC/MCSection.h" -#include "llvm/MC/MCContext.h" -#include "llvm/MC/MCSymbol.h" -#include "llvm/MC/MCExpr.h" -#include "llvm/MC/MCValue.h" -#include "llvm/MC/MCAssembler.h" -#include "llvm/MC/MCAsmLayout.h" -#include "llvm/MC/MCSectionCOFF.h" - +#include "llvm/MC/MCWinCOFFObjectWriter.h" #include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/STLExtras.h" #include "llvm/ADT/StringMap.h" #include "llvm/ADT/StringRef.h" - +#include "llvm/ADT/Twine.h" +#include "llvm/MC/MCAsmLayout.h" +#include "llvm/MC/MCAssembler.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCObjectFileInfo.h" +#include "llvm/MC/MCObjectWriter.h" +#include "llvm/MC/MCSection.h" +#include "llvm/MC/MCSectionCOFF.h" +#include "llvm/MC/MCSymbolCOFF.h" +#include "llvm/MC/MCValue.h" +#include "llvm/MC/StringTableBuilder.h" #include "llvm/Support/COFF.h" #include "llvm/Support/Debug.h" +#include "llvm/Support/Endian.h" #include "llvm/Support/ErrorHandling.h" - -#include "llvm/System/TimeValue.h" - +#include "llvm/Support/JamCRC.h" +#include "llvm/Support/TimeValue.h" #include +#include using namespace llvm; +#define DEBUG_TYPE "WinCOFFObjectWriter" + namespace { -typedef llvm::SmallString name; +typedef SmallString name; enum AuxiliaryType { ATFunctionDefinition, @@ -49,34 +53,47 @@ enum AuxiliaryType { }; struct AuxSymbol { - AuxiliaryType AuxType; + AuxiliaryType AuxType; COFF::Auxiliary Aux; }; +class COFFSymbol; +class COFFSection; + class COFFSymbol { public: COFF::symbol Data; - typedef llvm::SmallVector AuxiliarySymbols; + typedef SmallVector AuxiliarySymbols; - name Name; - size_t Index; + name Name; + int Index; AuxiliarySymbols Aux; - COFFSymbol *Other; + COFFSymbol *Other; + COFFSection *Section; + int Relocations; - MCSymbolData const *MCData; + const MCSymbol *MC; - COFFSymbol(llvm::StringRef name, size_t index); - size_t size() const; + COFFSymbol(StringRef name); void set_name_offset(uint32_t Offset); + + bool should_keep() const; + + int64_t getIndex() const { return Index; } + void setIndex(int Value) { + Index = Value; + if (MC) + MC->setIndex(static_cast(Value)); + } }; // This class contains staging data for a COFF relocation entry. struct COFFRelocation { COFF::relocation Data; - COFFSymbol *Symb; + COFFSymbol *Symb; - COFFRelocation() : Symb(NULL) {} + COFFRelocation() : Symb(nullptr) {} static size_t size() { return COFF::RelocationSize; } }; @@ -86,125 +103,112 @@ class COFFSection { public: COFF::section Header; - std::string Name; - size_t Number; - MCSectionData const *MCData; - COFFSymbol *Symb; - relocations Relocations; + std::string Name; + int Number; + MCSectionCOFF const *MCSection; + COFFSymbol *Symbol; + relocations Relocations; - COFFSection(llvm::StringRef name, size_t Index); + COFFSection(StringRef name); static size_t size(); }; -// This class holds the COFF string table. -class StringTable { - typedef llvm::StringMap map; - map Map; - - void update_length(); -public: - std::vector Data; - - StringTable(); - size_t size() const; - size_t insert(llvm::StringRef String); -}; - class WinCOFFObjectWriter : public MCObjectWriter { public: + typedef std::vector> symbols; + typedef std::vector> sections; - typedef std::vector symbols; - typedef std::vector sections; + typedef DenseMap symbol_map; + typedef DenseMap section_map; - typedef StringMap name_symbol_map; - typedef StringMap name_section_map; - - typedef DenseMap symbol_map; - typedef DenseMap section_map; + std::unique_ptr TargetObjectWriter; // Root level file contents. COFF::header Header; - sections Sections; - symbols Symbols; - StringTable Strings; + sections Sections; + symbols Symbols; + StringTableBuilder Strings; // Maps used during object file creation. section_map SectionMap; - symbol_map SymbolMap; + symbol_map SymbolMap; + + bool UseBigObj; - WinCOFFObjectWriter(raw_ostream &OS); - ~WinCOFFObjectWriter(); + WinCOFFObjectWriter(MCWinCOFFObjectTargetWriter *MOTW, raw_pwrite_stream &OS); - COFFSymbol *createSymbol(llvm::StringRef Name); - COFFSection *createSection(llvm::StringRef Name); + void reset() override { + memset(&Header, 0, sizeof(Header)); + Header.Machine = TargetObjectWriter->getMachine(); + Sections.clear(); + Symbols.clear(); + Strings.clear(); + SectionMap.clear(); + SymbolMap.clear(); + MCObjectWriter::reset(); + } - void InitCOFFEntity(COFFSymbol &Symbol); - void InitCOFFEntity(COFFSection &Section); + COFFSymbol *createSymbol(StringRef Name); + COFFSymbol *GetOrCreateCOFFSymbol(const MCSymbol *Symbol); + COFFSection *createSection(StringRef Name); template - object_t *createCOFFEntity(llvm::StringRef Name, list_t &List); + object_t *createCOFFEntity(StringRef Name, list_t &List); - void DefineSection(MCSectionData const &SectionData); - void DefineSymbol(MCSymbolData const &SymbolData, MCAssembler &Assembler); + void defineSection(MCSectionCOFF const &Sec); + void DefineSymbol(const MCSymbol &Symbol, MCAssembler &Assembler, + const MCAsmLayout &Layout); - bool ExportSection(COFFSection *S); - bool ExportSymbol(MCSymbolData const &SymbolData, MCAssembler &Asm); + void SetSymbolName(COFFSymbol &S); + void SetSectionName(COFFSection &S); + + bool ExportSymbol(const MCSymbol &Symbol, MCAssembler &Asm); + + bool IsPhysicalSection(COFFSection *S); // Entity writing methods. void WriteFileHeader(const COFF::header &Header); - void WriteSymbol(const COFFSymbol *S); + void WriteSymbol(const COFFSymbol &S); void WriteAuxiliarySymbols(const COFFSymbol::AuxiliarySymbols &S); - void WriteSectionHeader(const COFF::section &S); + void writeSectionHeader(const COFF::section &S); void WriteRelocation(const COFF::relocation &R); // MCObjectWriter interface implementation. - void ExecutePostLayoutBinding(MCAssembler &Asm); + void executePostLayoutBinding(MCAssembler &Asm, + const MCAsmLayout &Layout) override; - void RecordRelocation(const MCAssembler &Asm, - const MCAsmLayout &Layout, - const MCFragment *Fragment, - const MCFixup &Fixup, - MCValue Target, - uint64_t &FixedValue); + bool isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, + const MCSymbol &SymA, + const MCFragment &FB, bool InSet, + bool IsPCRel) const override; - void WriteObject(const MCAssembler &Asm, const MCAsmLayout &Layout); -}; -} + bool isWeak(const MCSymbol &Sym) const override; -static inline void write_uint32_le(void *Data, uint32_t const &Value) { - uint8_t *Ptr = reinterpret_cast(Data); - Ptr[0] = (Value & 0x000000FF) >> 0; - Ptr[1] = (Value & 0x0000FF00) >> 8; - Ptr[2] = (Value & 0x00FF0000) >> 16; - Ptr[3] = (Value & 0xFF000000) >> 24; -} + void recordRelocation(MCAssembler &Asm, const MCAsmLayout &Layout, + const MCFragment *Fragment, const MCFixup &Fixup, + MCValue Target, bool &IsPCRel, + uint64_t &FixedValue) override; -static inline void write_uint16_le(void *Data, uint16_t const &Value) { - uint8_t *Ptr = reinterpret_cast(Data); - Ptr[0] = (Value & 0x00FF) >> 0; - Ptr[1] = (Value & 0xFF00) >> 8; + void writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override; +}; } -static inline void write_uint8_le(void *Data, uint8_t const &Value) { - uint8_t *Ptr = reinterpret_cast(Data); - Ptr[0] = (Value & 0xFF) >> 0; +static inline void write_uint32_le(void *Data, uint32_t Value) { + support::endian::write(Data, + Value); } //------------------------------------------------------------------------------ // Symbol class implementation -COFFSymbol::COFFSymbol(llvm::StringRef name, size_t index) - : Name(name.begin(), name.end()), Index(-1) - , Other(NULL), MCData(NULL) { +COFFSymbol::COFFSymbol(StringRef name) + : Name(name.begin(), name.end()), Other(nullptr), Section(nullptr), + Relocations(0), MC(nullptr) { memset(&Data, 0, sizeof(Data)); } -size_t COFFSymbol::size() const { - return COFF::SymbolSize + (Data.NumberOfAuxSymbols * COFF::SymbolSize); -} - // In the case that the name does not fit within 8 bytes, the offset // into the string table is stored in the last 4 bytes instead, leaving // the first 4 bytes as 0. @@ -213,216 +217,205 @@ void COFFSymbol::set_name_offset(uint32_t Offset) { write_uint32_le(Data.Name + 4, Offset); } -//------------------------------------------------------------------------------ -// Section class implementation +/// logic to decide if the symbol should be reported in the symbol table +bool COFFSymbol::should_keep() const { + // no section means its external, keep it + if (!Section) + return true; -COFFSection::COFFSection(llvm::StringRef name, size_t Index) - : Name(name), Number(Index + 1) - , MCData(NULL), Symb(NULL) { - memset(&Header, 0, sizeof(Header)); -} + // if it has relocations pointing at it, keep it + if (Relocations > 0) { + assert(Section->Number != -1 && "Sections with relocations must be real!"); + return true; + } -size_t COFFSection::size() { - return COFF::SectionSize; -} + // if this is a safeseh handler, keep it + if (MC && (cast(MC)->isSafeSEH())) + return true; -//------------------------------------------------------------------------------ -// StringTable class implementation + // if the section its in is being droped, drop it + if (Section->Number == -1) + return false; -/// Write the length of the string table into Data. -/// The length of the string table includes uint32 length header. -void StringTable::update_length() { - write_uint32_le(&Data.front(), Data.size()); -} + // if it is the section symbol, keep it + if (Section->Symbol == this) + return true; -StringTable::StringTable() { - // The string table data begins with the length of the entire string table - // including the length header. Allocate space for this header. - Data.resize(4); -} + // if its temporary, drop it + if (MC && MC->isTemporary()) + return false; -size_t StringTable::size() const { - return Data.size(); + // otherwise, keep it + return true; } -/// Add String to the table iff it is not already there. -/// @returns the index into the string table where the string is now located. -size_t StringTable::insert(llvm::StringRef String) { - map::iterator i = Map.find(String); - - if (i != Map.end()) - return i->second; - - size_t Offset = Data.size(); - - // Insert string data into string table. - Data.insert(Data.end(), String.begin(), String.end()); - Data.push_back('\0'); - - // Put a reference to it in the map. - Map[String] = Offset; - - // Update the internal length field. - update_length(); +//------------------------------------------------------------------------------ +// Section class implementation - return Offset; +COFFSection::COFFSection(StringRef name) + : Name(name), MCSection(nullptr), Symbol(nullptr) { + memset(&Header, 0, sizeof(Header)); } +size_t COFFSection::size() { return COFF::SectionSize; } + //------------------------------------------------------------------------------ // WinCOFFObjectWriter class implementation -WinCOFFObjectWriter::WinCOFFObjectWriter(raw_ostream &OS) - : MCObjectWriter(OS, true) { +WinCOFFObjectWriter::WinCOFFObjectWriter(MCWinCOFFObjectTargetWriter *MOTW, + raw_pwrite_stream &OS) + : MCObjectWriter(OS, true), TargetObjectWriter(MOTW) { memset(&Header, 0, sizeof(Header)); - // TODO: Move magic constant out to COFF.h - Header.Machine = 0x14C; // x86 -} -WinCOFFObjectWriter::~WinCOFFObjectWriter() { - for (symbols::iterator I = Symbols.begin(), E = Symbols.end(); I != E; ++I) - delete *I; - for (sections::iterator I = Sections.begin(), E = Sections.end(); I != E; ++I) - delete *I; + Header.Machine = TargetObjectWriter->getMachine(); } -COFFSymbol *WinCOFFObjectWriter::createSymbol(llvm::StringRef Name) { +COFFSymbol *WinCOFFObjectWriter::createSymbol(StringRef Name) { return createCOFFEntity(Name, Symbols); } -COFFSection *WinCOFFObjectWriter::createSection(llvm::StringRef Name) { - return createCOFFEntity(Name, Sections); -} - -/// This function initializes a symbol by entering its name into the string -/// table if it is too long to fit in the symbol table header. -void WinCOFFObjectWriter::InitCOFFEntity(COFFSymbol &S) { - if (S.Name.size() > COFF::NameSize) { - size_t StringTableEntry = Strings.insert(S.Name.c_str()); - - S.set_name_offset(StringTableEntry); - } else - memcpy(S.Data.Name, S.Name.c_str(), S.Name.size()); +COFFSymbol *WinCOFFObjectWriter::GetOrCreateCOFFSymbol(const MCSymbol *Symbol) { + symbol_map::iterator i = SymbolMap.find(Symbol); + if (i != SymbolMap.end()) + return i->second; + COFFSymbol *RetSymbol = + createCOFFEntity(Symbol->getName(), Symbols); + SymbolMap[Symbol] = RetSymbol; + return RetSymbol; } -/// This function initializes a section by entering its name into the string -/// table if it is too long to fit in the section table header. -void WinCOFFObjectWriter::InitCOFFEntity(COFFSection &S) { - if (S.Name.size() > COFF::NameSize) { - size_t StringTableEntry = Strings.insert(S.Name.c_str()); - - // FIXME: Why is this number 999999? This number is never mentioned in the - // spec. I'm assuming this is due to the printed value needing to fit into - // the S.Header.Name field. In which case why not 9999999 (7 9's instead of - // 6)? The spec does not state if this entry should be null terminated in - // this case, and thus this seems to be the best way to do it. I think I - // just solved my own FIXME... - if (StringTableEntry > 999999) - report_fatal_error("COFF string table is greater than 999999 bytes."); - - sprintf(S.Header.Name, "/%d", (unsigned)StringTableEntry); - } else - memcpy(S.Header.Name, S.Name.c_str(), S.Name.size()); +COFFSection *WinCOFFObjectWriter::createSection(StringRef Name) { + return createCOFFEntity(Name, Sections); } /// A template used to lookup or create a symbol/section, and initialize it if /// needed. template -object_t *WinCOFFObjectWriter::createCOFFEntity(llvm::StringRef Name, - list_t &List) { - object_t *Object = new object_t(Name, List.size()); - - InitCOFFEntity(*Object); - - List.push_back(Object); +object_t *WinCOFFObjectWriter::createCOFFEntity(StringRef Name, list_t &List) { + List.push_back(make_unique(Name)); - return Object; + return List.back().get(); } /// This function takes a section data object from the assembler /// and creates the associated COFF section staging object. -void WinCOFFObjectWriter::DefineSection(MCSectionData const &SectionData) { - // FIXME: Not sure how to verify this (at least in a debug build). - MCSectionCOFF const &Sec = - static_cast(SectionData.getSection()); - +void WinCOFFObjectWriter::defineSection(MCSectionCOFF const &Sec) { COFFSection *coff_section = createSection(Sec.getSectionName()); - COFFSymbol *coff_symbol = createSymbol(Sec.getSectionName()); + COFFSymbol *coff_symbol = createSymbol(Sec.getSectionName()); + if (Sec.getSelection() != COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE) { + if (const MCSymbol *S = Sec.getCOMDATSymbol()) { + COFFSymbol *COMDATSymbol = GetOrCreateCOFFSymbol(S); + if (COMDATSymbol->Section) + report_fatal_error("two sections have the same comdat"); + COMDATSymbol->Section = coff_section; + } + } - coff_section->Symb = coff_symbol; + coff_section->Symbol = coff_symbol; + coff_symbol->Section = coff_section; coff_symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_STATIC; - coff_symbol->Data.SectionNumber = coff_section->Number; // In this case the auxiliary symbol is a Section Definition. coff_symbol->Aux.resize(1); memset(&coff_symbol->Aux[0], 0, sizeof(coff_symbol->Aux[0])); coff_symbol->Aux[0].AuxType = ATSectionDefinition; - coff_symbol->Aux[0].Aux.SectionDefinition.Number = coff_section->Number; coff_symbol->Aux[0].Aux.SectionDefinition.Selection = Sec.getSelection(); coff_section->Header.Characteristics = Sec.getCharacteristics(); uint32_t &Characteristics = coff_section->Header.Characteristics; - switch (SectionData.getAlignment()) { - case 1: Characteristics |= COFF::IMAGE_SCN_ALIGN_1BYTES; break; - case 2: Characteristics |= COFF::IMAGE_SCN_ALIGN_2BYTES; break; - case 4: Characteristics |= COFF::IMAGE_SCN_ALIGN_4BYTES; break; - case 8: Characteristics |= COFF::IMAGE_SCN_ALIGN_8BYTES; break; - case 16: Characteristics |= COFF::IMAGE_SCN_ALIGN_16BYTES; break; - case 32: Characteristics |= COFF::IMAGE_SCN_ALIGN_32BYTES; break; - case 64: Characteristics |= COFF::IMAGE_SCN_ALIGN_64BYTES; break; - case 128: Characteristics |= COFF::IMAGE_SCN_ALIGN_128BYTES; break; - case 256: Characteristics |= COFF::IMAGE_SCN_ALIGN_256BYTES; break; - case 512: Characteristics |= COFF::IMAGE_SCN_ALIGN_512BYTES; break; - case 1024: Characteristics |= COFF::IMAGE_SCN_ALIGN_1024BYTES; break; - case 2048: Characteristics |= COFF::IMAGE_SCN_ALIGN_2048BYTES; break; - case 4096: Characteristics |= COFF::IMAGE_SCN_ALIGN_4096BYTES; break; - case 8192: Characteristics |= COFF::IMAGE_SCN_ALIGN_8192BYTES; break; + switch (Sec.getAlignment()) { + case 1: + Characteristics |= COFF::IMAGE_SCN_ALIGN_1BYTES; + break; + case 2: + Characteristics |= COFF::IMAGE_SCN_ALIGN_2BYTES; + break; + case 4: + Characteristics |= COFF::IMAGE_SCN_ALIGN_4BYTES; + break; + case 8: + Characteristics |= COFF::IMAGE_SCN_ALIGN_8BYTES; + break; + case 16: + Characteristics |= COFF::IMAGE_SCN_ALIGN_16BYTES; + break; + case 32: + Characteristics |= COFF::IMAGE_SCN_ALIGN_32BYTES; + break; + case 64: + Characteristics |= COFF::IMAGE_SCN_ALIGN_64BYTES; + break; + case 128: + Characteristics |= COFF::IMAGE_SCN_ALIGN_128BYTES; + break; + case 256: + Characteristics |= COFF::IMAGE_SCN_ALIGN_256BYTES; + break; + case 512: + Characteristics |= COFF::IMAGE_SCN_ALIGN_512BYTES; + break; + case 1024: + Characteristics |= COFF::IMAGE_SCN_ALIGN_1024BYTES; + break; + case 2048: + Characteristics |= COFF::IMAGE_SCN_ALIGN_2048BYTES; + break; + case 4096: + Characteristics |= COFF::IMAGE_SCN_ALIGN_4096BYTES; + break; + case 8192: + Characteristics |= COFF::IMAGE_SCN_ALIGN_8192BYTES; + break; default: llvm_unreachable("unsupported section alignment"); } // Bind internal COFF section to MC section. - coff_section->MCData = &SectionData; - SectionMap[&SectionData] = coff_section; + coff_section->MCSection = &Sec; + SectionMap[&Sec] = coff_section; } -/// This function takes a section data object from the assembler -/// and creates the associated COFF symbol staging object. -void WinCOFFObjectWriter::DefineSymbol(MCSymbolData const &SymbolData, - MCAssembler &Assembler) { - COFFSymbol *coff_symbol = createSymbol(SymbolData.getSymbol().getName()); +static uint64_t getSymbolValue(const MCSymbol &Symbol, + const MCAsmLayout &Layout) { + if (Symbol.isCommon() && Symbol.isExternal()) + return Symbol.getCommonSize(); - coff_symbol->Data.Type = (SymbolData.getFlags() & 0x0000FFFF) >> 0; - coff_symbol->Data.StorageClass = (SymbolData.getFlags() & 0x00FF0000) >> 16; + uint64_t Res; + if (!Layout.getSymbolOffset(Symbol, Res)) + return 0; - // If no storage class was specified in the streamer, define it here. - if (coff_symbol->Data.StorageClass == 0) { - bool external = SymbolData.isExternal() || (SymbolData.Fragment == NULL); + return Res; +} - coff_symbol->Data.StorageClass = - external ? COFF::IMAGE_SYM_CLASS_EXTERNAL : COFF::IMAGE_SYM_CLASS_STATIC; - } +/// This function takes a symbol data object from the assembler +/// and creates the associated COFF symbol staging object. +void WinCOFFObjectWriter::DefineSymbol(const MCSymbol &Symbol, + MCAssembler &Assembler, + const MCAsmLayout &Layout) { + COFFSymbol *coff_symbol = GetOrCreateCOFFSymbol(&Symbol); + SymbolMap[&Symbol] = coff_symbol; - if (SymbolData.getFlags() & COFF::SF_WeakReference) { + if (cast(Symbol).isWeakExternal()) { coff_symbol->Data.StorageClass = COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL; - const MCExpr *Value = SymbolData.getSymbol().getVariableValue(); - - // FIXME: This assert message isn't very good. - assert(Value->getKind() == MCExpr::SymbolRef && - "Value must be a SymbolRef!"); - - const MCSymbolRefExpr *SymbolRef = - static_cast(Value); - - const MCSymbolData &OtherSymbolData = - Assembler.getSymbolData(SymbolRef->getSymbol()); - - // FIXME: This assert message isn't very good. - assert(SymbolMap.find(&OtherSymbolData) != SymbolMap.end() && - "OtherSymbolData must be in the symbol map!"); - - coff_symbol->Other = SymbolMap[&OtherSymbolData]; + if (Symbol.isVariable()) { + const MCSymbolRefExpr *SymRef = + dyn_cast(Symbol.getVariableValue()); + + if (!SymRef) + report_fatal_error("Weak externals may only alias symbols"); + + coff_symbol->Other = GetOrCreateCOFFSymbol(&SymRef->getSymbol()); + } else { + std::string WeakName = (".weak." + Symbol.getName() + ".default").str(); + COFFSymbol *WeakDefault = createSymbol(WeakName); + WeakDefault->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE; + WeakDefault->Data.StorageClass = COFF::IMAGE_SYM_CLASS_EXTERNAL; + WeakDefault->Data.Type = 0; + WeakDefault->Data.Value = 0; + coff_symbol->Other = WeakDefault; + } // Setup the Weak External auxiliary symbol. coff_symbol->Aux.resize(1); @@ -430,315 +423,719 @@ void WinCOFFObjectWriter::DefineSymbol(MCSymbolData const &SymbolData, coff_symbol->Aux[0].AuxType = ATWeakExternal; coff_symbol->Aux[0].Aux.WeakExternal.TagIndex = 0; coff_symbol->Aux[0].Aux.WeakExternal.Characteristics = - COFF::IMAGE_WEAK_EXTERN_SEARCH_LIBRARY; + COFF::IMAGE_WEAK_EXTERN_SEARCH_LIBRARY; + + coff_symbol->MC = &Symbol; + } else { + const MCSymbol *Base = Layout.getBaseSymbol(Symbol); + coff_symbol->Data.Value = getSymbolValue(Symbol, Layout); + + const MCSymbolCOFF &SymbolCOFF = cast(Symbol); + coff_symbol->Data.Type = SymbolCOFF.getType(); + coff_symbol->Data.StorageClass = SymbolCOFF.getClass(); + + // If no storage class was specified in the streamer, define it here. + if (coff_symbol->Data.StorageClass == COFF::IMAGE_SYM_CLASS_NULL) { + bool IsExternal = Symbol.isExternal() || + (!Symbol.getFragment() && !Symbol.isVariable()); + + coff_symbol->Data.StorageClass = IsExternal + ? COFF::IMAGE_SYM_CLASS_EXTERNAL + : COFF::IMAGE_SYM_CLASS_STATIC; + } + + if (!Base) { + coff_symbol->Data.SectionNumber = COFF::IMAGE_SYM_ABSOLUTE; + } else { + if (Base->getFragment()) { + COFFSection *Sec = SectionMap[Base->getFragment()->getParent()]; + + if (coff_symbol->Section && coff_symbol->Section != Sec) + report_fatal_error("conflicting sections for symbol"); + + coff_symbol->Section = Sec; + } + } + + coff_symbol->MC = &Symbol; } +} - // Bind internal COFF symbol to MC symbol. - coff_symbol->MCData = &SymbolData; - SymbolMap[&SymbolData] = coff_symbol; +// Maximum offsets for different string table entry encodings. +static const unsigned Max6DecimalOffset = 999999; +static const unsigned Max7DecimalOffset = 9999999; +static const uint64_t MaxBase64Offset = 0xFFFFFFFFFULL; // 64^6, including 0 + +// Encode a string table entry offset in base 64, padded to 6 chars, and +// prefixed with a double slash: '//AAAAAA', '//AAAAAB', ... +// Buffer must be at least 8 bytes large. No terminating null appended. +static void encodeBase64StringEntry(char *Buffer, uint64_t Value) { + assert(Value > Max7DecimalOffset && Value <= MaxBase64Offset && + "Illegal section name encoding for value"); + + static const char Alphabet[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "abcdefghijklmnopqrstuvwxyz" + "0123456789+/"; + + Buffer[0] = '/'; + Buffer[1] = '/'; + + char *Ptr = Buffer + 7; + for (unsigned i = 0; i < 6; ++i) { + unsigned Rem = Value % 64; + Value /= 64; + *(Ptr--) = Alphabet[Rem]; + } +} + +void WinCOFFObjectWriter::SetSectionName(COFFSection &S) { + if (S.Name.size() > COFF::NameSize) { + uint64_t StringTableEntry = Strings.getOffset(S.Name); + + if (StringTableEntry <= Max6DecimalOffset) { + std::sprintf(S.Header.Name, "/%d", unsigned(StringTableEntry)); + } else if (StringTableEntry <= Max7DecimalOffset) { + // With seven digits, we have to skip the terminating null. Because + // sprintf always appends it, we use a larger temporary buffer. + char buffer[9] = {}; + std::sprintf(buffer, "/%d", unsigned(StringTableEntry)); + std::memcpy(S.Header.Name, buffer, 8); + } else if (StringTableEntry <= MaxBase64Offset) { + // Starting with 10,000,000, offsets are encoded as base64. + encodeBase64StringEntry(S.Header.Name, StringTableEntry); + } else { + report_fatal_error("COFF string table is greater than 64 GB."); + } + } else + std::memcpy(S.Header.Name, S.Name.c_str(), S.Name.size()); } -bool WinCOFFObjectWriter::ExportSection(COFFSection *S) { - return (S->Header.Characteristics - & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA) == 0; +void WinCOFFObjectWriter::SetSymbolName(COFFSymbol &S) { + if (S.Name.size() > COFF::NameSize) + S.set_name_offset(Strings.getOffset(S.Name)); + else + std::memcpy(S.Data.Name, S.Name.c_str(), S.Name.size()); } -bool WinCOFFObjectWriter::ExportSymbol(MCSymbolData const &SymbolData, +bool WinCOFFObjectWriter::ExportSymbol(const MCSymbol &Symbol, MCAssembler &Asm) { // This doesn't seem to be right. Strings referred to from the .data section // need symbols so they can be linked to code in the .text section right? - // return Asm.isSymbolLinkerVisible (&SymbolData); + // return Asm.isSymbolLinkerVisible(Symbol); - // For now, all symbols are exported, the linker will sort it out for us. - return true; + // Non-temporary labels should always be visible to the linker. + if (!Symbol.isTemporary()) + return true; + + // Temporary variable symbols are invisible. + if (Symbol.isVariable()) + return false; + + // Absolute temporary labels are never visible. + return !Symbol.isAbsolute(); +} + +bool WinCOFFObjectWriter::IsPhysicalSection(COFFSection *S) { + return (S->Header.Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA) == + 0; } //------------------------------------------------------------------------------ // entity writing methods void WinCOFFObjectWriter::WriteFileHeader(const COFF::header &Header) { - WriteLE16(Header.Machine); - WriteLE16(Header.NumberOfSections); - WriteLE32(Header.TimeDateStamp); - WriteLE32(Header.PointerToSymbolTable); - WriteLE32(Header.NumberOfSymbols); - WriteLE16(Header.SizeOfOptionalHeader); - WriteLE16(Header.Characteristics); + if (UseBigObj) { + writeLE16(COFF::IMAGE_FILE_MACHINE_UNKNOWN); + writeLE16(0xFFFF); + writeLE16(COFF::BigObjHeader::MinBigObjectVersion); + writeLE16(Header.Machine); + writeLE32(Header.TimeDateStamp); + writeBytes(StringRef(COFF::BigObjMagic, sizeof(COFF::BigObjMagic))); + writeLE32(0); + writeLE32(0); + writeLE32(0); + writeLE32(0); + writeLE32(Header.NumberOfSections); + writeLE32(Header.PointerToSymbolTable); + writeLE32(Header.NumberOfSymbols); + } else { + writeLE16(Header.Machine); + writeLE16(static_cast(Header.NumberOfSections)); + writeLE32(Header.TimeDateStamp); + writeLE32(Header.PointerToSymbolTable); + writeLE32(Header.NumberOfSymbols); + writeLE16(Header.SizeOfOptionalHeader); + writeLE16(Header.Characteristics); + } } -void WinCOFFObjectWriter::WriteSymbol(const COFFSymbol *S) { - WriteBytes(StringRef(S->Data.Name, COFF::NameSize)); - WriteLE32(S->Data.Value); - WriteLE16(S->Data.SectionNumber); - WriteLE16(S->Data.Type); - Write8(S->Data.StorageClass); - Write8(S->Data.NumberOfAuxSymbols); - WriteAuxiliarySymbols(S->Aux); +void WinCOFFObjectWriter::WriteSymbol(const COFFSymbol &S) { + writeBytes(StringRef(S.Data.Name, COFF::NameSize)); + writeLE32(S.Data.Value); + if (UseBigObj) + writeLE32(S.Data.SectionNumber); + else + writeLE16(static_cast(S.Data.SectionNumber)); + writeLE16(S.Data.Type); + write8(S.Data.StorageClass); + write8(S.Data.NumberOfAuxSymbols); + WriteAuxiliarySymbols(S.Aux); } void WinCOFFObjectWriter::WriteAuxiliarySymbols( - const COFFSymbol::AuxiliarySymbols &S) { - for(COFFSymbol::AuxiliarySymbols::const_iterator i = S.begin(), e = S.end(); - i != e; ++i) { - switch(i->AuxType) { + const COFFSymbol::AuxiliarySymbols &S) { + for (COFFSymbol::AuxiliarySymbols::const_iterator i = S.begin(), e = S.end(); + i != e; ++i) { + switch (i->AuxType) { case ATFunctionDefinition: - WriteLE32(i->Aux.FunctionDefinition.TagIndex); - WriteLE32(i->Aux.FunctionDefinition.TotalSize); - WriteLE32(i->Aux.FunctionDefinition.PointerToLinenumber); - WriteLE32(i->Aux.FunctionDefinition.PointerToNextFunction); + writeLE32(i->Aux.FunctionDefinition.TagIndex); + writeLE32(i->Aux.FunctionDefinition.TotalSize); + writeLE32(i->Aux.FunctionDefinition.PointerToLinenumber); + writeLE32(i->Aux.FunctionDefinition.PointerToNextFunction); WriteZeros(sizeof(i->Aux.FunctionDefinition.unused)); + if (UseBigObj) + WriteZeros(COFF::Symbol32Size - COFF::Symbol16Size); break; case ATbfAndefSymbol: WriteZeros(sizeof(i->Aux.bfAndefSymbol.unused1)); - WriteLE16(i->Aux.bfAndefSymbol.Linenumber); + writeLE16(i->Aux.bfAndefSymbol.Linenumber); WriteZeros(sizeof(i->Aux.bfAndefSymbol.unused2)); - WriteLE32(i->Aux.bfAndefSymbol.PointerToNextFunction); + writeLE32(i->Aux.bfAndefSymbol.PointerToNextFunction); WriteZeros(sizeof(i->Aux.bfAndefSymbol.unused3)); + if (UseBigObj) + WriteZeros(COFF::Symbol32Size - COFF::Symbol16Size); break; case ATWeakExternal: - WriteLE32(i->Aux.WeakExternal.TagIndex); - WriteLE32(i->Aux.WeakExternal.Characteristics); + writeLE32(i->Aux.WeakExternal.TagIndex); + writeLE32(i->Aux.WeakExternal.Characteristics); WriteZeros(sizeof(i->Aux.WeakExternal.unused)); + if (UseBigObj) + WriteZeros(COFF::Symbol32Size - COFF::Symbol16Size); break; case ATFile: - WriteBytes(StringRef(reinterpret_cast(i->Aux.File.FileName), - sizeof(i->Aux.File.FileName))); + writeBytes( + StringRef(reinterpret_cast(&i->Aux), + UseBigObj ? COFF::Symbol32Size : COFF::Symbol16Size)); break; case ATSectionDefinition: - WriteLE32(i->Aux.SectionDefinition.Length); - WriteLE16(i->Aux.SectionDefinition.NumberOfRelocations); - WriteLE16(i->Aux.SectionDefinition.NumberOfLinenumbers); - WriteLE32(i->Aux.SectionDefinition.CheckSum); - WriteLE16(i->Aux.SectionDefinition.Number); - Write8(i->Aux.SectionDefinition.Selection); + writeLE32(i->Aux.SectionDefinition.Length); + writeLE16(i->Aux.SectionDefinition.NumberOfRelocations); + writeLE16(i->Aux.SectionDefinition.NumberOfLinenumbers); + writeLE32(i->Aux.SectionDefinition.CheckSum); + writeLE16(static_cast(i->Aux.SectionDefinition.Number)); + write8(i->Aux.SectionDefinition.Selection); WriteZeros(sizeof(i->Aux.SectionDefinition.unused)); + writeLE16(static_cast(i->Aux.SectionDefinition.Number >> 16)); + if (UseBigObj) + WriteZeros(COFF::Symbol32Size - COFF::Symbol16Size); break; } } } -void WinCOFFObjectWriter::WriteSectionHeader(const COFF::section &S) { - WriteBytes(StringRef(S.Name, COFF::NameSize)); - - WriteLE32(S.VirtualSize); - WriteLE32(S.VirtualAddress); - WriteLE32(S.SizeOfRawData); - WriteLE32(S.PointerToRawData); - WriteLE32(S.PointerToRelocations); - WriteLE32(S.PointerToLineNumbers); - WriteLE16(S.NumberOfRelocations); - WriteLE16(S.NumberOfLineNumbers); - WriteLE32(S.Characteristics); +void WinCOFFObjectWriter::writeSectionHeader(const COFF::section &S) { + writeBytes(StringRef(S.Name, COFF::NameSize)); + + writeLE32(S.VirtualSize); + writeLE32(S.VirtualAddress); + writeLE32(S.SizeOfRawData); + writeLE32(S.PointerToRawData); + writeLE32(S.PointerToRelocations); + writeLE32(S.PointerToLineNumbers); + writeLE16(S.NumberOfRelocations); + writeLE16(S.NumberOfLineNumbers); + writeLE32(S.Characteristics); } void WinCOFFObjectWriter::WriteRelocation(const COFF::relocation &R) { - WriteLE32(R.VirtualAddress); - WriteLE32(R.SymbolTableIndex); - WriteLE16(R.Type); + writeLE32(R.VirtualAddress); + writeLE32(R.SymbolTableIndex); + writeLE16(R.Type); } //////////////////////////////////////////////////////////////////////////////// // MCObjectWriter interface implementations -void WinCOFFObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm) { +void WinCOFFObjectWriter::executePostLayoutBinding(MCAssembler &Asm, + const MCAsmLayout &Layout) { // "Define" each section & symbol. This creates section & symbol - // entries in the staging area and gives them their final indexes. + // entries in the staging area. + for (const auto &Section : Asm) + defineSection(static_cast(Section)); - for (MCAssembler::const_iterator i = Asm.begin(), e = Asm.end(); i != e; i++) - DefineSection(*i); + for (const MCSymbol &Symbol : Asm.symbols()) + if (ExportSymbol(Symbol, Asm)) + DefineSymbol(Symbol, Asm, Layout); +} - for (MCAssembler::const_symbol_iterator i = Asm.symbol_begin(), - e = Asm.symbol_end(); i != e; i++) { - if (ExportSymbol(*i, Asm)) - DefineSymbol(*i, Asm); - } +bool WinCOFFObjectWriter::isSymbolRefDifferenceFullyResolvedImpl( + const MCAssembler &Asm, const MCSymbol &SymA, const MCFragment &FB, + bool InSet, bool IsPCRel) const { + // MS LINK expects to be able to replace all references to a function with a + // thunk to implement their /INCREMENTAL feature. Make sure we don't optimize + // away any relocations to functions. + uint16_t Type = cast(SymA).getType(); + if ((Type >> COFF::SCT_COMPLEX_TYPE_SHIFT) == COFF::IMAGE_SYM_DTYPE_FUNCTION) + return false; + return MCObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(Asm, SymA, FB, + InSet, IsPCRel); } -void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm, - const MCAsmLayout &Layout, - const MCFragment *Fragment, - const MCFixup &Fixup, - MCValue Target, - uint64_t &FixedValue) { - assert(Target.getSymA() != NULL && "Relocation must reference a symbol!"); - assert(Target.getSymB() == NULL && - "Relocation must reference only one symbol!"); +bool WinCOFFObjectWriter::isWeak(const MCSymbol &Sym) const { + if (!Sym.isExternal()) + return false; + + if (!Sym.isInSection()) + return false; - MCSectionData const *SectionData = Fragment->getParent(); - MCSymbolData const *SymbolData = - &Asm.getSymbolData(Target.getSymA()->getSymbol()); + const auto &Sec = cast(Sym.getSection()); + if (!Sec.getCOMDATSymbol()) + return false; - assert(SectionMap.find(SectionData) != SectionMap.end() && - "Section must already have been defined in ExecutePostLayoutBinding!"); - assert(SymbolMap.find(SymbolData) != SymbolMap.end() && - "Symbol must already have been defined in ExecutePostLayoutBinding!"); + // It looks like for COFF it is invalid to replace a reference to a global + // in a comdat with a reference to a local. + // FIXME: Add a specification reference if available. + return true; +} + +void WinCOFFObjectWriter::recordRelocation( + MCAssembler &Asm, const MCAsmLayout &Layout, const MCFragment *Fragment, + const MCFixup &Fixup, MCValue Target, bool &IsPCRel, uint64_t &FixedValue) { + assert(Target.getSymA() && "Relocation must reference a symbol!"); + + const MCSymbol &Symbol = Target.getSymA()->getSymbol(); + const MCSymbol &A = Symbol; + if (!A.isRegistered()) + Asm.getContext().reportFatalError(Fixup.getLoc(), + Twine("symbol '") + A.getName() + + "' can not be undefined"); + if (A.isTemporary() && A.isUndefined()) { + Asm.getContext().reportFatalError(Fixup.getLoc(), + Twine("assembler label '") + A.getName() + + "' can not be undefined"); + } - COFFSection *coff_section = SectionMap[SectionData]; - COFFSymbol *coff_symbol = SymbolMap[SymbolData]; + MCSection *Section = Fragment->getParent(); + + // Mark this symbol as requiring an entry in the symbol table. + assert(SectionMap.find(Section) != SectionMap.end() && + "Section must already have been defined in executePostLayoutBinding!"); + assert(SymbolMap.find(&A) != SymbolMap.end() && + "Symbol must already have been defined in executePostLayoutBinding!"); + + COFFSection *coff_section = SectionMap[Section]; + COFFSymbol *coff_symbol = SymbolMap[&A]; + const MCSymbolRefExpr *SymB = Target.getSymB(); + bool CrossSection = false; + + if (SymB) { + const MCSymbol *B = &SymB->getSymbol(); + if (!B->getFragment()) + Asm.getContext().reportFatalError( + Fixup.getLoc(), + Twine("symbol '") + B->getName() + + "' can not be undefined in a subtraction expression"); + + if (!A.getFragment()) + Asm.getContext().reportFatalError( + Fixup.getLoc(), + Twine("symbol '") + Symbol.getName() + + "' can not be undefined in a subtraction expression"); + + CrossSection = &Symbol.getSection() != &B->getSection(); + + // Offset of the symbol in the section + int64_t OffsetOfB = Layout.getSymbolOffset(*B); + + // In the case where we have SymbA and SymB, we just need to store the delta + // between the two symbols. Update FixedValue to account for the delta, and + // skip recording the relocation. + if (!CrossSection) { + int64_t OffsetOfA = Layout.getSymbolOffset(A); + FixedValue = (OffsetOfA - OffsetOfB) + Target.getConstant(); + return; + } - FixedValue = Target.getConstant(); + // Offset of the relocation in the section + int64_t OffsetOfRelocation = + Layout.getFragmentOffset(Fragment) + Fixup.getOffset(); + + FixedValue = (OffsetOfRelocation - OffsetOfB) + Target.getConstant(); + } else { + FixedValue = Target.getConstant(); + } COFFRelocation Reloc; Reloc.Data.SymbolTableIndex = 0; Reloc.Data.VirtualAddress = Layout.getFragmentOffset(Fragment); - Reloc.Symb = coff_symbol; - Reloc.Data.VirtualAddress += Fixup.getOffset(); + // Turn relocations for temporary symbols into section relocations. + if (coff_symbol->MC->isTemporary() || CrossSection) { + Reloc.Symb = coff_symbol->Section->Symbol; + FixedValue += Layout.getFragmentOffset(coff_symbol->MC->getFragment()) + + coff_symbol->MC->getOffset(); + } else + Reloc.Symb = coff_symbol; - switch (Fixup.getKind()) { - case FirstTargetFixupKind: // reloc_pcrel_4byte - Reloc.Data.Type = COFF::IMAGE_REL_I386_REL32; + ++Reloc.Symb->Relocations; + + Reloc.Data.VirtualAddress += Fixup.getOffset(); + Reloc.Data.Type = TargetObjectWriter->getRelocType( + Target, Fixup, CrossSection, Asm.getBackend()); + + // FIXME: Can anyone explain what this does other than adjust for the size + // of the offset? + if ((Header.Machine == COFF::IMAGE_FILE_MACHINE_AMD64 && + Reloc.Data.Type == COFF::IMAGE_REL_AMD64_REL32) || + (Header.Machine == COFF::IMAGE_FILE_MACHINE_I386 && + Reloc.Data.Type == COFF::IMAGE_REL_I386_REL32)) FixedValue += 4; - break; - case FK_Data_4: - Reloc.Data.Type = COFF::IMAGE_REL_I386_DIR32; - break; - default: - llvm_unreachable("unsupported relocation type"); + + if (Header.Machine == COFF::IMAGE_FILE_MACHINE_ARMNT) { + switch (Reloc.Data.Type) { + case COFF::IMAGE_REL_ARM_ABSOLUTE: + case COFF::IMAGE_REL_ARM_ADDR32: + case COFF::IMAGE_REL_ARM_ADDR32NB: + case COFF::IMAGE_REL_ARM_TOKEN: + case COFF::IMAGE_REL_ARM_SECTION: + case COFF::IMAGE_REL_ARM_SECREL: + break; + case COFF::IMAGE_REL_ARM_BRANCH11: + case COFF::IMAGE_REL_ARM_BLX11: + // IMAGE_REL_ARM_BRANCH11 and IMAGE_REL_ARM_BLX11 are only used for + // pre-ARMv7, which implicitly rules it out of ARMNT (it would be valid + // for Windows CE). + case COFF::IMAGE_REL_ARM_BRANCH24: + case COFF::IMAGE_REL_ARM_BLX24: + case COFF::IMAGE_REL_ARM_MOV32A: + // IMAGE_REL_ARM_BRANCH24, IMAGE_REL_ARM_BLX24, IMAGE_REL_ARM_MOV32A are + // only used for ARM mode code, which is documented as being unsupported + // by Windows on ARM. Empirical proof indicates that masm is able to + // generate the relocations however the rest of the MSVC toolchain is + // unable to handle it. + llvm_unreachable("unsupported relocation"); + break; + case COFF::IMAGE_REL_ARM_MOV32T: + break; + case COFF::IMAGE_REL_ARM_BRANCH20T: + case COFF::IMAGE_REL_ARM_BRANCH24T: + case COFF::IMAGE_REL_ARM_BLX23T: + // IMAGE_REL_BRANCH20T, IMAGE_REL_ARM_BRANCH24T, IMAGE_REL_ARM_BLX23T all + // perform a 4 byte adjustment to the relocation. Relative branches are + // offset by 4 on ARM, however, because there is no RELA relocations, all + // branches are offset by 4. + FixedValue = FixedValue + 4; + break; + } } - coff_section->Relocations.push_back(Reloc); + if (TargetObjectWriter->recordRelocation(Fixup)) + coff_section->Relocations.push_back(Reloc); } -void WinCOFFObjectWriter::WriteObject(const MCAssembler &Asm, +void WinCOFFObjectWriter::writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) { + size_t SectionsSize = Sections.size(); + if (SectionsSize > static_cast(INT32_MAX)) + report_fatal_error( + "PE COFF object files can't have more than 2147483647 sections"); + // Assign symbol and section indexes and offsets. + int32_t NumberOfSections = static_cast(SectionsSize); - Header.NumberOfSymbols = 0; + UseBigObj = NumberOfSections > COFF::MaxNumberOfSections16; - for (symbols::iterator i = Symbols.begin(), e = Symbols.end(); i != e; i++) { - COFFSymbol *coff_symbol = *i; - MCSymbolData const *SymbolData = coff_symbol->MCData; + // Assign section numbers. + size_t Number = 1; + for (const auto &Section : Sections) { + Section->Number = Number; + Section->Symbol->Data.SectionNumber = Number; + Section->Symbol->Aux[0].Aux.SectionDefinition.Number = Number; + ++Number; + } - coff_symbol->Index = Header.NumberOfSymbols++; + Header.NumberOfSections = NumberOfSections; + Header.NumberOfSymbols = 0; - // Update section number & offset for symbols that have them. - if ((SymbolData != NULL) && (SymbolData->Fragment != NULL)) { - COFFSection *coff_section = SectionMap[SymbolData->Fragment->getParent()]; + for (const std::string &Name : Asm.getFileNames()) { + // round up to calculate the number of auxiliary symbols required + unsigned SymbolSize = UseBigObj ? COFF::Symbol32Size : COFF::Symbol16Size; + unsigned Count = (Name.size() + SymbolSize - 1) / SymbolSize; + + COFFSymbol *file = createSymbol(".file"); + file->Data.SectionNumber = COFF::IMAGE_SYM_DEBUG; + file->Data.StorageClass = COFF::IMAGE_SYM_CLASS_FILE; + file->Aux.resize(Count); + + unsigned Offset = 0; + unsigned Length = Name.size(); + for (auto &Aux : file->Aux) { + Aux.AuxType = ATFile; + + if (Length > SymbolSize) { + memcpy(&Aux.Aux, Name.c_str() + Offset, SymbolSize); + Length = Length - SymbolSize; + } else { + memcpy(&Aux.Aux, Name.c_str() + Offset, Length); + memset((char *)&Aux.Aux + Length, 0, SymbolSize - Length); + break; + } - coff_symbol->Data.SectionNumber = coff_section->Number; - coff_symbol->Data.Value = Layout.getFragmentOffset(SymbolData->Fragment); + Offset += SymbolSize; } + } - // Update auxiliary symbol info. - coff_symbol->Data.NumberOfAuxSymbols = coff_symbol->Aux.size(); - Header.NumberOfSymbols += coff_symbol->Data.NumberOfAuxSymbols; + for (auto &Symbol : Symbols) { + // Update section number & offset for symbols that have them. + if (Symbol->Section) + Symbol->Data.SectionNumber = Symbol->Section->Number; + if (Symbol->should_keep()) { + Symbol->setIndex(Header.NumberOfSymbols++); + // Update auxiliary symbol info. + Symbol->Data.NumberOfAuxSymbols = Symbol->Aux.size(); + Header.NumberOfSymbols += Symbol->Data.NumberOfAuxSymbols; + } else { + Symbol->setIndex(-1); + } } - // Fixup weak external references. - for (symbols::iterator i = Symbols.begin(), e = Symbols.end(); i != e; i++) { - COFFSymbol *symb = *i; + // Build string table. + for (const auto &S : Sections) + if (S->Name.size() > COFF::NameSize) + Strings.add(S->Name); + for (const auto &S : Symbols) + if (S->should_keep() && S->Name.size() > COFF::NameSize) + Strings.add(S->Name); + Strings.finalize(StringTableBuilder::WinCOFF); + + // Set names. + for (const auto &S : Sections) + SetSectionName(*S); + for (auto &S : Symbols) + if (S->should_keep()) + SetSymbolName(*S); - if (symb->Other != NULL) { - assert(symb->Aux.size() == 1 && - "Symbol must contain one aux symbol!"); - assert(symb->Aux[0].AuxType == ATWeakExternal && + // Fixup weak external references. + for (auto &Symbol : Symbols) { + if (Symbol->Other) { + assert(Symbol->getIndex() != -1); + assert(Symbol->Aux.size() == 1 && "Symbol must contain one aux symbol!"); + assert(Symbol->Aux[0].AuxType == ATWeakExternal && "Symbol's aux symbol must be a Weak External!"); - symb->Aux[0].Aux.WeakExternal.TagIndex = symb->Other->Index; + Symbol->Aux[0].Aux.WeakExternal.TagIndex = Symbol->Other->getIndex(); } } + // Fixup associative COMDAT sections. + for (auto &Section : Sections) { + if (Section->Symbol->Aux[0].Aux.SectionDefinition.Selection != + COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE) + continue; + + const MCSectionCOFF &MCSec = *Section->MCSection; + + const MCSymbol *COMDAT = MCSec.getCOMDATSymbol(); + assert(COMDAT); + COFFSymbol *COMDATSymbol = GetOrCreateCOFFSymbol(COMDAT); + assert(COMDATSymbol); + COFFSection *Assoc = COMDATSymbol->Section; + if (!Assoc) + report_fatal_error( + Twine("Missing associated COMDAT section for section ") + + MCSec.getSectionName()); + + // Skip this section if the associated section is unused. + if (Assoc->Number == -1) + continue; + + Section->Symbol->Aux[0].Aux.SectionDefinition.Number = Assoc->Number; + } + // Assign file offsets to COFF object file structures. unsigned offset = 0; - offset += COFF::HeaderSize; - offset += COFF::SectionSize * Asm.size(); + if (UseBigObj) + offset += COFF::Header32Size; + else + offset += COFF::Header16Size; + offset += COFF::SectionSize * Header.NumberOfSections; - Header.NumberOfSections = Sections.size(); + for (const auto &Section : Asm) { + COFFSection *Sec = SectionMap[&Section]; - for (MCAssembler::const_iterator i = Asm.begin(), - e = Asm.end(); - i != e; i++) { - COFFSection *Sec = SectionMap[i]; + if (Sec->Number == -1) + continue; - Sec->Header.SizeOfRawData = Layout.getSectionFileSize(i); + Sec->Header.SizeOfRawData = Layout.getSectionAddressSize(&Section); - if (ExportSection(Sec)) { + if (IsPhysicalSection(Sec)) { + // Align the section data to a four byte boundary. + offset = RoundUpToAlignment(offset, 4); Sec->Header.PointerToRawData = offset; offset += Sec->Header.SizeOfRawData; } if (Sec->Relocations.size() > 0) { - Sec->Header.NumberOfRelocations = Sec->Relocations.size(); + bool RelocationsOverflow = Sec->Relocations.size() >= 0xffff; + + if (RelocationsOverflow) { + // Signal overflow by setting NumberOfRelocations to max value. Actual + // size is found in reloc #0. Microsoft tools understand this. + Sec->Header.NumberOfRelocations = 0xffff; + } else { + Sec->Header.NumberOfRelocations = Sec->Relocations.size(); + } Sec->Header.PointerToRelocations = offset; + if (RelocationsOverflow) { + // Reloc #0 will contain actual count, so make room for it. + offset += COFF::RelocationSize; + } + offset += COFF::RelocationSize * Sec->Relocations.size(); - for (relocations::iterator cr = Sec->Relocations.begin(), - er = Sec->Relocations.end(); - cr != er; cr++) { - (*cr).Data.SymbolTableIndex = (*cr).Symb->Index; + for (auto &Relocation : Sec->Relocations) { + assert(Relocation.Symb->getIndex() != -1); + Relocation.Data.SymbolTableIndex = Relocation.Symb->getIndex(); } } - assert(Sec->Symb->Aux.size() == 1 && "Section's symbol must have one aux!"); - AuxSymbol &Aux = Sec->Symb->Aux[0]; + assert(Sec->Symbol->Aux.size() == 1 && + "Section's symbol must have one aux!"); + AuxSymbol &Aux = Sec->Symbol->Aux[0]; assert(Aux.AuxType == ATSectionDefinition && "Section's symbol's aux symbol must be a Section Definition!"); Aux.Aux.SectionDefinition.Length = Sec->Header.SizeOfRawData; Aux.Aux.SectionDefinition.NumberOfRelocations = - Sec->Header.NumberOfRelocations; + Sec->Header.NumberOfRelocations; Aux.Aux.SectionDefinition.NumberOfLinenumbers = - Sec->Header.NumberOfLineNumbers; + Sec->Header.NumberOfLineNumbers; } Header.PointerToSymbolTable = offset; - Header.TimeDateStamp = sys::TimeValue::now().toEpochTime(); +#if (ENABLE_TIMESTAMPS == 1) + // MS LINK expects to be able to use this timestamp to implement their + // /INCREMENTAL feature. + std::time_t Now = time(nullptr); + if (Now < 0 || !isUInt<32>(Now)) + Now = UINT32_MAX; + Header.TimeDateStamp = Now; +#else + // We want a deterministic output. It looks like GNU as also writes 0 in here. + Header.TimeDateStamp = 0; +#endif // Write it all to disk... WriteFileHeader(Header); { sections::iterator i, ie; - MCAssembler::const_iterator j, je; + MCAssembler::iterator j, je; + + for (auto &Section : Sections) { + if (Section->Number != -1) { + if (Section->Relocations.size() >= 0xffff) + Section->Header.Characteristics |= COFF::IMAGE_SCN_LNK_NRELOC_OVFL; + writeSectionHeader(Section->Header); + } + } - for (i = Sections.begin(), ie = Sections.end(); i != ie; i++) - WriteSectionHeader((*i)->Header); + SmallVector SectionContents; + for (i = Sections.begin(), ie = Sections.end(), j = Asm.begin(), + je = Asm.end(); + (i != ie) && (j != je); ++i, ++j) { + + if ((*i)->Number == -1) + continue; - for (i = Sections.begin(), ie = Sections.end(), - j = Asm.begin(), je = Asm.end(); - (i != ie) && (j != je); i++, j++) { if ((*i)->Header.PointerToRawData != 0) { - assert(OS.tell() == (*i)->Header.PointerToRawData && + assert(getStream().tell() <= (*i)->Header.PointerToRawData && "Section::PointerToRawData is insane!"); - Asm.WriteSectionData(j, Layout, this); + unsigned SectionDataPadding = + (*i)->Header.PointerToRawData - getStream().tell(); + assert(SectionDataPadding < 4 && + "Should only need at most three bytes of padding!"); + + WriteZeros(SectionDataPadding); + + // Save the contents of the section to a temporary buffer, we need this + // to CRC the data before we dump it into the object file. + SectionContents.clear(); + raw_svector_ostream VecOS(SectionContents); + raw_pwrite_stream &OldStream = getStream(); + // Redirect the output stream to our buffer. + setStream(VecOS); + // Fill our buffer with the section data. + Asm.writeSectionData(&*j, Layout); + // Reset the stream back to what it was before. + setStream(OldStream); + + // Calculate our CRC with an initial value of '0', this is not how + // JamCRC is specified but it aligns with the expected output. + JamCRC JC(/*Init=*/0x00000000U); + JC.update(SectionContents); + + // Write the section contents to the object file. + getStream() << SectionContents; + + // Update the section definition auxiliary symbol to record the CRC. + COFFSection *Sec = SectionMap[&*j]; + COFFSymbol::AuxiliarySymbols &AuxSyms = Sec->Symbol->Aux; + assert(AuxSyms.size() == 1 && + AuxSyms[0].AuxType == ATSectionDefinition); + AuxSymbol &SecDef = AuxSyms[0]; + SecDef.Aux.SectionDefinition.CheckSum = JC.getCRC(); } if ((*i)->Relocations.size() > 0) { - assert(OS.tell() == (*i)->Header.PointerToRelocations && + assert(getStream().tell() == (*i)->Header.PointerToRelocations && "Section::PointerToRelocations is insane!"); - for (relocations::const_iterator k = (*i)->Relocations.begin(), - ke = (*i)->Relocations.end(); - k != ke; k++) { - WriteRelocation(k->Data); + if ((*i)->Relocations.size() >= 0xffff) { + // In case of overflow, write actual relocation count as first + // relocation. Including the synthetic reloc itself (+ 1). + COFF::relocation r; + r.VirtualAddress = (*i)->Relocations.size() + 1; + r.SymbolTableIndex = 0; + r.Type = 0; + WriteRelocation(r); } + + for (const auto &Relocation : (*i)->Relocations) + WriteRelocation(Relocation.Data); } else assert((*i)->Header.PointerToRelocations == 0 && "Section::PointerToRelocations is insane!"); } } - assert(OS.tell() == Header.PointerToSymbolTable && + assert(getStream().tell() == Header.PointerToSymbolTable && "Header::PointerToSymbolTable is insane!"); - for (symbols::iterator i = Symbols.begin(), e = Symbols.end(); i != e; i++) - WriteSymbol(*i); + for (auto &Symbol : Symbols) + if (Symbol->getIndex() != -1) + WriteSymbol(*Symbol); - OS.write((char const *)&Strings.Data.front(), Strings.Data.size()); + getStream().write(Strings.data().data(), Strings.data().size()); } +MCWinCOFFObjectTargetWriter::MCWinCOFFObjectTargetWriter(unsigned Machine_) + : Machine(Machine_) {} + +// Pin the vtable to this file. +void MCWinCOFFObjectTargetWriter::anchor() {} + //------------------------------------------------------------------------------ // WinCOFFObjectWriter factory function -namespace llvm { - MCObjectWriter *createWinCOFFObjectWriter(raw_ostream &OS) { - return new WinCOFFObjectWriter(OS); - } +MCObjectWriter * +llvm::createWinCOFFObjectWriter(MCWinCOFFObjectTargetWriter *MOTW, + raw_pwrite_stream &OS) { + return new WinCOFFObjectWriter(MOTW, OS); }