X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FMCDwarf.cpp;h=890b03170b027fd8f33cb54fa27c0b750cc4f2e6;hb=09f089a39ecc90256225d922e6ee42b689af22a9;hp=a89201730a54c73083cdb5b7bb0f51fbacde7c39;hpb=99cb622041a0839c7dfcf0263c5102a305a0fdb5;p=oota-llvm.git diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp index a89201730a5..890b03170b0 100644 --- a/lib/MC/MCDwarf.cpp +++ b/lib/MC/MCDwarf.cpp @@ -9,6 +9,7 @@ #include "llvm/MC/MCDwarf.h" #include "llvm/ADT/Hashing.h" +#include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallString.h" #include "llvm/ADT/Twine.h" #include "llvm/Config/config.h" @@ -16,8 +17,9 @@ #include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCObjectFileInfo.h" +#include "llvm/MC/MCObjectStreamer.h" #include "llvm/MC/MCRegisterInfo.h" -#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCSection.h" #include "llvm/MC/MCSymbol.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" @@ -62,7 +64,7 @@ static inline uint64_t ScaleAddrDelta(MCContext &Context, uint64_t AddrDelta) { // and if there is information from the last .loc directive that has yet to have // a line entry made for it is made. // -void MCLineEntry::Make(MCStreamer *MCOS, const MCSection *Section) { +void MCLineEntry::Make(MCObjectStreamer *MCOS, const MCSection *Section) { if (!MCOS->getContext().getDwarfLocSeen()) return; @@ -80,23 +82,11 @@ void MCLineEntry::Make(MCStreamer *MCOS, const MCSection *Section) { // clear DwarfLocSeen saying the current .loc info is now used. MCOS->getContext().ClearDwarfLocSeen(); - // Get the MCLineSection for this section, if one does not exist for this - // section create it. - const DenseMap &MCLineSections = - MCOS->getContext().getMCLineSections(); - MCLineSection *LineSection = MCLineSections.lookup(Section); - if (!LineSection) { - // Create a new MCLineSection. This will be deleted after the dwarf line - // table is created using it by iterating through the MCLineSections - // DenseMap. - LineSection = new MCLineSection; - // Save a pointer to the new LineSection into the MCLineSections DenseMap. - MCOS->getContext().addMCLineSection(Section, LineSection); - } - // Add the line entry to this section's entries. - LineSection->addLineEntry(LineEntry, - MCOS->getContext().getDwarfCompileUnitID()); + MCOS->getContext() + .getMCDwarfLineTable(MCOS->getContext().getDwarfCompileUnitID()) + .getMCLineSections() + .addLineEntry(LineEntry, Section); } // @@ -124,25 +114,21 @@ static inline const MCExpr *MakeStartMinusEndExpr(const MCStreamer &MCOS, // This emits the Dwarf line table for the specified section from the entries // in the LineSection. // -static inline void EmitDwarfLineTable(MCStreamer *MCOS, - const MCSection *Section, - const MCLineSection *LineSection, - unsigned CUID) { - // This LineSection does not contain any LineEntry for the given Compile Unit. - if (!LineSection->containEntriesForID(CUID)) - return; - +static inline void +EmitDwarfLineTable(MCObjectStreamer *MCOS, const MCSection *Section, + const MCLineSection::MCLineEntryCollection &LineEntries) { unsigned FileNum = 1; unsigned LastLine = 1; unsigned Column = 0; unsigned Flags = DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_IS_STMT : 0; unsigned Isa = 0; - MCSymbol *LastLabel = NULL; + unsigned Discriminator = 0; + MCSymbol *LastLabel = nullptr; // Loop through each MCLineEntry and encode the dwarf line number table. - for (MCLineSection::const_iterator - it = LineSection->getMCLineEntries(CUID).begin(), - ie = LineSection->getMCLineEntries(CUID).end(); it != ie; ++it) { + for (auto it = LineEntries.begin(), + ie = LineEntries.end(); + it != ie; ++it) { if (FileNum != it->getFileNum()) { FileNum = it->getFileNum(); @@ -154,6 +140,14 @@ static inline void EmitDwarfLineTable(MCStreamer *MCOS, MCOS->EmitIntValue(dwarf::DW_LNS_set_column, 1); MCOS->EmitULEB128IntValue(Column); } + if (Discriminator != it->getDiscriminator()) { + Discriminator = it->getDiscriminator(); + unsigned Size = getULEB128Size(Discriminator); + MCOS->EmitIntValue(dwarf::DW_LNS_extended_op, 1); + MCOS->EmitULEB128IntValue(Size + 1); + MCOS->EmitIntValue(dwarf::DW_LNE_set_discriminator, 1); + MCOS->EmitULEB128IntValue(Discriminator); + } if (Isa != it->getIsa()) { Isa = it->getIsa(); MCOS->EmitIntValue(dwarf::DW_LNS_set_isa, 1); @@ -185,65 +179,90 @@ static inline void EmitDwarfLineTable(MCStreamer *MCOS, } // Emit a DW_LNE_end_sequence for the end of the section. - // Using the pointer Section create a temporary label at the end of the - // section and use that and the LastLabel to compute the address delta - // and use INT64_MAX as the line delta which is the signal that this is - // actually a DW_LNE_end_sequence. + // Use the section end label to compute the address delta and use INT64_MAX + // as the line delta which is the signal that this is actually a + // DW_LNE_end_sequence. + MCSymbol *SectionEnd = MCOS->endSection(Section); - // Switch to the section to be able to create a symbol at its end. - // TODO: keep track of the last subsection so that this symbol appears in the - // correct place. - MCOS->SwitchSection(Section); - - MCContext &context = MCOS->getContext(); - // Create a symbol at the end of the section. - MCSymbol *SectionEnd = context.CreateTempSymbol(); - // Set the value of the symbol, as we are at the end of the section. - MCOS->EmitLabel(SectionEnd); - - // Switch back the dwarf line section. - MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfLineSection()); + // Switch back the dwarf line section, in case endSection had to switch the + // section. + MCContext &Ctx = MCOS->getContext(); + MCOS->SwitchSection(Ctx.getObjectFileInfo()->getDwarfLineSection()); - const MCAsmInfo *asmInfo = MCOS->getContext().getAsmInfo(); + const MCAsmInfo *AsmInfo = Ctx.getAsmInfo(); MCOS->EmitDwarfAdvanceLineAddr(INT64_MAX, LastLabel, SectionEnd, - asmInfo->getPointerSize()); + AsmInfo->getPointerSize()); } // // This emits the Dwarf file and the line tables. // -const MCSymbol *MCDwarfFileTable::Emit(MCStreamer *MCOS) { +void MCDwarfLineTable::Emit(MCObjectStreamer *MCOS) { MCContext &context = MCOS->getContext(); + + auto &LineTables = context.getMCDwarfLineTables(); + + // Bail out early so we don't switch to the debug_line section needlessly and + // in doing so create an unnecessary (if empty) section. + if (LineTables.empty()) + return; + // Switch to the section where the table will be emitted into. MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfLineSection()); - const DenseMap &MCLineTableSymbols = - MCOS->getContext().getMCLineTableSymbols(); - // CUID and MCLineTableSymbols are set in DwarfDebug, when DwarfDebug does - // not exist, CUID will be 0 and MCLineTableSymbols will be empty. - // Handle Compile Unit 0, the line table start symbol is the section symbol. - const MCSymbol *LineStartSym = EmitCU(MCOS, 0); // Handle the rest of the Compile Units. - for (unsigned Is = 1, Ie = MCLineTableSymbols.size(); Is < Ie; Is++) - EmitCU(MCOS, Is); - - // Now delete the MCLineSections that were created in MCLineEntry::Make() - // and used to emit the line table. - const DenseMap &MCLineSections = - MCOS->getContext().getMCLineSections(); - for (DenseMap::const_iterator it = - MCLineSections.begin(), ie = MCLineSections.end(); it != ie; - ++it) - delete it->second; - - return LineStartSym; + for (const auto &CUIDTablePair : LineTables) + CUIDTablePair.second.EmitCU(MCOS); +} + +void MCDwarfDwoLineTable::Emit(MCStreamer &MCOS) const { + MCOS.EmitLabel(Header.Emit(&MCOS, None).second); +} + +std::pair MCDwarfLineTableHeader::Emit(MCStreamer *MCOS) const { + static const char StandardOpcodeLengths[] = { + 0, // length of DW_LNS_copy + 1, // length of DW_LNS_advance_pc + 1, // length of DW_LNS_advance_line + 1, // length of DW_LNS_set_file + 1, // length of DW_LNS_set_column + 0, // length of DW_LNS_negate_stmt + 0, // length of DW_LNS_set_basic_block + 0, // length of DW_LNS_const_add_pc + 1, // length of DW_LNS_fixed_advance_pc + 0, // length of DW_LNS_set_prologue_end + 0, // length of DW_LNS_set_epilogue_begin + 1 // DW_LNS_set_isa + }; + assert(array_lengthof(StandardOpcodeLengths) == + (DWARF2_LINE_OPCODE_BASE - 1)); + return Emit(MCOS, StandardOpcodeLengths); } -const MCSymbol *MCDwarfFileTable::EmitCU(MCStreamer *MCOS, unsigned CUID) { +static const MCExpr *forceExpAbs(MCStreamer &OS, const MCExpr* Expr) { + MCContext &Context = OS.getContext(); + assert(!isa(Expr)); + if (Context.getAsmInfo()->hasAggressiveSymbolFolding()) + return Expr; + + MCSymbol *ABS = Context.CreateTempSymbol(); + OS.EmitAssignment(ABS, Expr); + return MCSymbolRefExpr::Create(ABS, Context); +} + +static void emitAbsValue(MCStreamer &OS, const MCExpr *Value, unsigned Size) { + const MCExpr *ABS = forceExpAbs(OS, Value); + OS.EmitValue(ABS, Size); +} + +std::pair +MCDwarfLineTableHeader::Emit(MCStreamer *MCOS, + ArrayRef StandardOpcodeLengths) const { + MCContext &context = MCOS->getContext(); // Create a symbol at the beginning of the line table. - MCSymbol *LineStartSym = MCOS->getContext().getMCLineTableSymbol(CUID); + MCSymbol *LineStartSym = Label; if (!LineStartSym) LineStartSym = context.CreateTempSymbol(); // Set the value of the symbol, as we are at the start of the line table. @@ -254,8 +273,8 @@ const MCSymbol *MCDwarfFileTable::EmitCU(MCStreamer *MCOS, unsigned CUID) { // The first 4 bytes is the total length of the information for this // compilation unit (not including these 4 bytes for the length). - MCOS->EmitAbsValue(MakeStartMinusEndExpr(*MCOS, *LineStartSym, *LineEndSym,4), - 4); + emitAbsValue(*MCOS, + MakeStartMinusEndExpr(*MCOS, *LineStartSym, *LineEndSym, 4), 4); // Next 2 bytes is the Version, which is Dwarf 2. MCOS->EmitIntValue(2, 2); @@ -267,35 +286,24 @@ const MCSymbol *MCDwarfFileTable::EmitCU(MCStreamer *MCOS, unsigned CUID) { // section to the end of the prologue. Not including the 4 bytes for the // total length, the 2 bytes for the version, and these 4 bytes for the // length of the prologue. - MCOS->EmitAbsValue(MakeStartMinusEndExpr(*MCOS, *LineStartSym, *ProEndSym, - (4 + 2 + 4)), 4, 0); + emitAbsValue( + *MCOS, + MakeStartMinusEndExpr(*MCOS, *LineStartSym, *ProEndSym, (4 + 2 + 4)), 4); // Parameters of the state machine, are next. MCOS->EmitIntValue(context.getAsmInfo()->getMinInstAlignment(), 1); MCOS->EmitIntValue(DWARF2_LINE_DEFAULT_IS_STMT, 1); MCOS->EmitIntValue(DWARF2_LINE_BASE, 1); MCOS->EmitIntValue(DWARF2_LINE_RANGE, 1); - MCOS->EmitIntValue(DWARF2_LINE_OPCODE_BASE, 1); + MCOS->EmitIntValue(StandardOpcodeLengths.size() + 1, 1); // Standard opcode lengths - MCOS->EmitIntValue(0, 1); // length of DW_LNS_copy - MCOS->EmitIntValue(1, 1); // length of DW_LNS_advance_pc - MCOS->EmitIntValue(1, 1); // length of DW_LNS_advance_line - MCOS->EmitIntValue(1, 1); // length of DW_LNS_set_file - MCOS->EmitIntValue(1, 1); // length of DW_LNS_set_column - MCOS->EmitIntValue(0, 1); // length of DW_LNS_negate_stmt - MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_basic_block - MCOS->EmitIntValue(0, 1); // length of DW_LNS_const_add_pc - MCOS->EmitIntValue(1, 1); // length of DW_LNS_fixed_advance_pc - MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_prologue_end - MCOS->EmitIntValue(0, 1); // length of DW_LNS_set_epilogue_begin - MCOS->EmitIntValue(1, 1); // DW_LNS_set_isa + for (char Length : StandardOpcodeLengths) + MCOS->EmitIntValue(Length, 1); // Put out the directory and file tables. // First the directory table. - const SmallVectorImpl &MCDwarfDirs = - context.getMCDwarfDirs(CUID); for (unsigned i = 0; i < MCDwarfDirs.size(); i++) { MCOS->EmitBytes(MCDwarfDirs[i]); // the DirectoryName MCOS->EmitBytes(StringRef("\0", 1)); // the null term. of the string @@ -303,13 +311,12 @@ const MCSymbol *MCDwarfFileTable::EmitCU(MCStreamer *MCOS, unsigned CUID) { MCOS->EmitIntValue(0, 1); // Terminate the directory list // Second the file table. - const SmallVectorImpl &MCDwarfFiles = - MCOS->getContext().getMCDwarfFiles(CUID); for (unsigned i = 1; i < MCDwarfFiles.size(); i++) { - MCOS->EmitBytes(MCDwarfFiles[i]->getName()); // FileName + assert(!MCDwarfFiles[i].Name.empty()); + MCOS->EmitBytes(MCDwarfFiles[i].Name); // FileName MCOS->EmitBytes(StringRef("\0", 1)); // the null term. of the string // the Directory num - MCOS->EmitULEB128IntValue(MCDwarfFiles[i]->getDirIndex()); + MCOS->EmitULEB128IntValue(MCDwarfFiles[i].DirIndex); MCOS->EmitIntValue(0, 1); // last modification timestamp (always 0) MCOS->EmitIntValue(0, 1); // filesize (always 0) } @@ -319,36 +326,91 @@ const MCSymbol *MCDwarfFileTable::EmitCU(MCStreamer *MCOS, unsigned CUID) { // end of the prologue (that was used in a previous expression). MCOS->EmitLabel(ProEndSym); - // Put out the line tables. - const DenseMap &MCLineSections = - MCOS->getContext().getMCLineSections(); - const std::vector &MCLineSectionOrder = - MCOS->getContext().getMCLineSectionOrder(); - for (std::vector::const_iterator it = - MCLineSectionOrder.begin(), ie = MCLineSectionOrder.end(); it != ie; - ++it) { - const MCSection *Sec = *it; - const MCLineSection *Line = MCLineSections.lookup(Sec); - EmitDwarfLineTable(MCOS, Sec, Line, CUID); - } + return std::make_pair(LineStartSym, LineEndSym); +} - if (MCOS->getContext().getAsmInfo()->getLinkerRequiresNonEmptyDwarfLines() - && MCLineSectionOrder.begin() == MCLineSectionOrder.end()) { - // The darwin9 linker has a bug (see PR8715). For for 32-bit architectures - // it requires: - // total_length >= prologue_length + 10 - // We are 4 bytes short, since we have total_length = 51 and - // prologue_length = 45 +void MCDwarfLineTable::EmitCU(MCObjectStreamer *MCOS) const { + MCSymbol *LineEndSym = Header.Emit(MCOS).second; - // The regular end_sequence should be sufficient. - MCDwarfLineAddr::Emit(MCOS, INT64_MAX, 0); - } + // Put out the line tables. + for (const auto &LineSec : MCLineSections.getMCLineEntries()) + EmitDwarfLineTable(MCOS, LineSec.first, LineSec.second); // This is the end of the section, so set the value of the symbol at the end // of this section (that was used in a previous expression). MCOS->EmitLabel(LineEndSym); +} - return LineStartSym; +unsigned MCDwarfLineTable::getFile(StringRef &Directory, StringRef &FileName, + unsigned FileNumber) { + return Header.getFile(Directory, FileName, FileNumber); +} + +unsigned MCDwarfLineTableHeader::getFile(StringRef &Directory, + StringRef &FileName, + unsigned FileNumber) { + if (Directory == CompilationDir) + Directory = ""; + if (FileName.empty()) { + FileName = ""; + Directory = ""; + } + assert(!FileName.empty()); + if (FileNumber == 0) { + FileNumber = SourceIdMap.size() + 1; + assert((MCDwarfFiles.empty() || FileNumber == MCDwarfFiles.size()) && + "Don't mix autonumbered and explicit numbered line table usage"); + auto IterBool = SourceIdMap.insert( + std::make_pair((Directory + Twine('\0') + FileName).str(), FileNumber)); + if (!IterBool.second) + return IterBool.first->second; + } + // Make space for this FileNumber in the MCDwarfFiles vector if needed. + MCDwarfFiles.resize(FileNumber + 1); + + // Get the new MCDwarfFile slot for this FileNumber. + MCDwarfFile &File = MCDwarfFiles[FileNumber]; + + // It is an error to use see the same number more than once. + if (!File.Name.empty()) + return 0; + + if (Directory.empty()) { + // Separate the directory part from the basename of the FileName. + StringRef tFileName = sys::path::filename(FileName); + if (!tFileName.empty()) { + Directory = sys::path::parent_path(FileName); + if (!Directory.empty()) + FileName = tFileName; + } + } + + // Find or make an entry in the MCDwarfDirs vector for this Directory. + // Capture directory name. + unsigned DirIndex; + if (Directory.empty()) { + // For FileNames with no directories a DirIndex of 0 is used. + DirIndex = 0; + } else { + DirIndex = 0; + for (unsigned End = MCDwarfDirs.size(); DirIndex < End; DirIndex++) { + if (Directory == MCDwarfDirs[DirIndex]) + break; + } + if (DirIndex >= MCDwarfDirs.size()) + MCDwarfDirs.push_back(Directory); + // The DirIndex is one based, as DirIndex of 0 is used for FileNames with + // no directories. MCDwarfDirs[] is unlike MCDwarfFiles[] in that the + // directory names are stored at MCDwarfDirs[DirIndex-1] where FileNames + // are stored at MCDwarfFiles[FileNumber].Name . + DirIndex++; + } + + File.Name = FileName; + File.DirIndex = DirIndex; + + // return the allocated FileNumber. + return FileNumber; } /// Utility function to emit the encoding to a streamer. @@ -376,7 +438,7 @@ void MCDwarfLineAddr::Encode(MCContext &Context, int64_t LineDelta, if (LineDelta == INT64_MAX) { if (AddrDelta == MAX_SPECIAL_ADDR_DELTA) OS << char(dwarf::DW_LNS_const_add_pc); - else { + else if (AddrDelta) { OS << char(dwarf::DW_LNS_advance_pc); encodeULEB128(AddrDelta, OS); } @@ -437,16 +499,6 @@ void MCDwarfLineAddr::Encode(MCContext &Context, int64_t LineDelta, OS << char(Temp); } -void MCDwarfFile::print(raw_ostream &OS) const { - OS << '"' << getName() << '"'; -} - -#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) -void MCDwarfFile::dump() const { - print(dbgs()); -} -#endif - // Utility function to write a tuple for .debug_abbrev. static void EmitAbbrev(MCStreamer *MCOS, uint64_t Name, uint64_t Form) { MCOS->EmitULEB128IntValue(Name); @@ -464,10 +516,16 @@ static void EmitGenDwarfAbbrev(MCStreamer *MCOS) { MCOS->EmitULEB128IntValue(dwarf::DW_TAG_compile_unit); MCOS->EmitIntValue(dwarf::DW_CHILDREN_yes, 1); EmitAbbrev(MCOS, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4); - EmitAbbrev(MCOS, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr); - EmitAbbrev(MCOS, dwarf::DW_AT_high_pc, dwarf::DW_FORM_addr); + if (MCOS->getContext().getGenDwarfSectionSyms().size() > 1 && + MCOS->getContext().getDwarfVersion() >= 3) { + EmitAbbrev(MCOS, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4); + } else { + EmitAbbrev(MCOS, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr); + EmitAbbrev(MCOS, dwarf::DW_AT_high_pc, dwarf::DW_FORM_addr); + } EmitAbbrev(MCOS, dwarf::DW_AT_name, dwarf::DW_FORM_string); - EmitAbbrev(MCOS, dwarf::DW_AT_comp_dir, dwarf::DW_FORM_string); + if (!context.getCompilationDir().empty()) + EmitAbbrev(MCOS, dwarf::DW_AT_comp_dir, dwarf::DW_FORM_string); StringRef DwarfDebugFlags = context.getDwarfDebugFlags(); if (!DwarfDebugFlags.empty()) EmitAbbrev(MCOS, dwarf::DW_AT_APPLE_flags, dwarf::DW_FORM_string); @@ -497,20 +555,14 @@ static void EmitGenDwarfAbbrev(MCStreamer *MCOS) { } // When generating dwarf for assembly source files this emits the data for -// .debug_aranges section. Which contains a header and a table of pairs of -// PointerSize'ed values for the address and size of section(s) with line table -// entries (just the default .text in our case) and a terminating pair of zeros. +// .debug_aranges section. This section contains a header and a table of pairs +// of PointerSize'ed values for the address and size of section(s) with line +// table entries. static void EmitGenDwarfAranges(MCStreamer *MCOS, const MCSymbol *InfoSectionSymbol) { MCContext &context = MCOS->getContext(); - // Create a symbol at the end of the section that we are creating the dwarf - // debugging info to use later in here as part of the expression to calculate - // the size of the section for the table. - MCOS->SwitchSection(context.getGenDwarfSection()); - MCSymbol *SectionEndSym = context.CreateTempSymbol(); - MCOS->EmitLabel(SectionEndSym); - context.setGenDwarfSectionEndSym(SectionEndSym); + auto &Sections = context.getGenDwarfSectionSyms(); MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfARangesSection()); @@ -528,8 +580,8 @@ static void EmitGenDwarfAranges(MCStreamer *MCOS, Length += Pad; // Add the size of the pair of PointerSize'ed values for the address and size - // of the one default .text section we have in the table. - Length += 2 * AddrSize; + // of each section we have in the table. + Length += 2 * AddrSize * Sections.size(); // And the pair of terminating zeros. Length += 2 * AddrSize; @@ -542,7 +594,8 @@ static void EmitGenDwarfAranges(MCStreamer *MCOS, // The 4 byte offset to the compile unit in the .debug_info from the start // of the .debug_info. if (InfoSectionSymbol) - MCOS->EmitSymbolValue(InfoSectionSymbol, 4); + MCOS->EmitSymbolValue(InfoSectionSymbol, 4, + asmInfo->needsDwarfSectionOffsetDirective()); else MCOS->EmitIntValue(0, 4); // The 1 byte size of an address. @@ -553,14 +606,21 @@ static void EmitGenDwarfAranges(MCStreamer *MCOS, for(int i = 0; i < Pad; i++) MCOS->EmitIntValue(0, 1); - // Now emit the table of pairs of PointerSize'ed values for the section(s) - // address and size, in our case just the one default .text section. - const MCExpr *Addr = MCSymbolRefExpr::Create( - context.getGenDwarfSectionStartSym(), MCSymbolRefExpr::VK_None, context); - const MCExpr *Size = MakeStartMinusEndExpr(*MCOS, - *context.getGenDwarfSectionStartSym(), *SectionEndSym, 0); - MCOS->EmitAbsValue(Addr, AddrSize); - MCOS->EmitAbsValue(Size, AddrSize); + // Now emit the table of pairs of PointerSize'ed values for the section + // addresses and sizes. + for (const auto &sec : Sections) { + MCSymbol *StartSymbol = sec.second.first; + MCSymbol *EndSymbol = sec.second.second; + assert(StartSymbol && "StartSymbol must not be NULL"); + assert(EndSymbol && "EndSymbol must not be NULL"); + + const MCExpr *Addr = MCSymbolRefExpr::Create( + StartSymbol, MCSymbolRefExpr::VK_None, context); + const MCExpr *Size = MakeStartMinusEndExpr(*MCOS, + *StartSymbol, *EndSymbol, 0); + MCOS->EmitValue(Addr, AddrSize); + emitAbsValue(*MCOS, Size, AddrSize); + } // And finally the pair of terminating zeros. MCOS->EmitIntValue(0, AddrSize); @@ -572,7 +632,8 @@ static void EmitGenDwarfAranges(MCStreamer *MCOS, // DIE and a list of label DIEs. static void EmitGenDwarfInfo(MCStreamer *MCOS, const MCSymbol *AbbrevSectionSymbol, - const MCSymbol *LineSectionSymbol) { + const MCSymbol *LineSectionSymbol, + const MCSymbol *RangesSectionSymbol) { MCContext &context = MCOS->getContext(); MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfInfoSection()); @@ -588,18 +649,19 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS, // The 4 byte total length of the information for this compilation unit, not // including these 4 bytes. const MCExpr *Length = MakeStartMinusEndExpr(*MCOS, *InfoStart, *InfoEnd, 4); - MCOS->EmitAbsValue(Length, 4); + emitAbsValue(*MCOS, Length, 4); - // The 2 byte DWARF version, which is 2. - MCOS->EmitIntValue(2, 2); + // The 2 byte DWARF version. + MCOS->EmitIntValue(context.getDwarfVersion(), 2); + const MCAsmInfo &AsmInfo = *context.getAsmInfo(); // The 4 byte offset to the debug abbrevs from the start of the .debug_abbrev, // it is at the start of that section so this is zero. - if (AbbrevSectionSymbol) { - MCOS->EmitSymbolValue(AbbrevSectionSymbol, 4); - } else { + if (AbbrevSectionSymbol == nullptr) MCOS->EmitIntValue(0, 4); - } + else + MCOS->EmitSymbolValue(AbbrevSectionSymbol, 4, + AsmInfo.needsDwarfSectionOffsetDirective()); const MCAsmInfo *asmInfo = context.getAsmInfo(); int AddrSize = asmInfo->getPointerSize(); @@ -613,38 +675,61 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS, // DW_AT_stmt_list, a 4 byte offset from the start of the .debug_line section, // which is at the start of that section so this is zero. - if (LineSectionSymbol) { - MCOS->EmitSymbolValue(LineSectionSymbol, 4); - } else { + if (LineSectionSymbol) + MCOS->EmitSymbolValue(LineSectionSymbol, 4, + AsmInfo.needsDwarfSectionOffsetDirective()); + else MCOS->EmitIntValue(0, 4); - } - // AT_low_pc, the first address of the default .text section. - const MCExpr *Start = MCSymbolRefExpr::Create( - context.getGenDwarfSectionStartSym(), MCSymbolRefExpr::VK_None, context); - MCOS->EmitAbsValue(Start, AddrSize); + if (RangesSectionSymbol) { + // There are multiple sections containing code, so we must use the + // .debug_ranges sections. - // AT_high_pc, the last address of the default .text section. - const MCExpr *End = MCSymbolRefExpr::Create( - context.getGenDwarfSectionEndSym(), MCSymbolRefExpr::VK_None, context); - MCOS->EmitAbsValue(End, AddrSize); + // AT_ranges, the 4 byte offset from the start of the .debug_ranges section + // to the address range list for this compilation unit. + MCOS->EmitSymbolValue(RangesSectionSymbol, 4); + } else { + // If we only have one non-empty code section, we can use the simpler + // AT_low_pc and AT_high_pc attributes. + + // Find the first (and only) non-empty text section + auto &Sections = context.getGenDwarfSectionSyms(); + const auto TextSection = Sections.begin(); + assert(TextSection != Sections.end() && "No text section found"); + + MCSymbol *StartSymbol = TextSection->second.first; + MCSymbol *EndSymbol = TextSection->second.second; + assert(StartSymbol && "StartSymbol must not be NULL"); + assert(EndSymbol && "EndSymbol must not be NULL"); + + // AT_low_pc, the first address of the default .text section. + const MCExpr *Start = MCSymbolRefExpr::Create( + StartSymbol, MCSymbolRefExpr::VK_None, context); + MCOS->EmitValue(Start, AddrSize); + + // AT_high_pc, the last address of the default .text section. + const MCExpr *End = MCSymbolRefExpr::Create( + EndSymbol, MCSymbolRefExpr::VK_None, context); + MCOS->EmitValue(End, AddrSize); + } // AT_name, the name of the source file. Reconstruct from the first directory // and file table entries. - const SmallVectorImpl &MCDwarfDirs = - context.getMCDwarfDirs(); + const SmallVectorImpl &MCDwarfDirs = context.getMCDwarfDirs(); if (MCDwarfDirs.size() > 0) { MCOS->EmitBytes(MCDwarfDirs[0]); - MCOS->EmitBytes("/"); + MCOS->EmitBytes(sys::path::get_separator()); } - const SmallVectorImpl &MCDwarfFiles = + const SmallVectorImpl &MCDwarfFiles = MCOS->getContext().getMCDwarfFiles(); - MCOS->EmitBytes(MCDwarfFiles[1]->getName()); + MCOS->EmitBytes(MCDwarfFiles[1].Name); MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string. // AT_comp_dir, the working directory the assembly was done in. - MCOS->EmitBytes(context.getCompilationDir()); - MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string. + if (!context.getCompilationDir().empty()) { + MCOS->EmitBytes(context.getCompilationDir()); + MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string. + } // AT_APPLE_flags, the command line arguments of the assembler tool. StringRef DwarfDebugFlags = context.getDwarfDebugFlags(); @@ -655,14 +740,10 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS, // AT_producer, the version of the assembler tool. StringRef DwarfDebugProducer = context.getDwarfDebugProducer(); - if (!DwarfDebugProducer.empty()){ + if (!DwarfDebugProducer.empty()) MCOS->EmitBytes(DwarfDebugProducer); - } - else { - MCOS->EmitBytes(StringRef("llvm-mc (based on LLVM ")); - MCOS->EmitBytes(StringRef(PACKAGE_VERSION)); - MCOS->EmitBytes(StringRef(")")); - } + else + MCOS->EmitBytes(StringRef("llvm-mc (based on LLVM " PACKAGE_VERSION ")")); MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string. // AT_language, a 4 byte value. We use DW_LANG_Mips_Assembler as the dwarf2 @@ -672,30 +753,26 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS, // Third part: the list of label DIEs. // Loop on saved info for dwarf labels and create the DIEs for them. - const std::vector &Entries = - MCOS->getContext().getMCGenDwarfLabelEntries(); - for (std::vector::const_iterator it = - Entries.begin(), ie = Entries.end(); it != ie; - ++it) { - const MCGenDwarfLabelEntry *Entry = *it; - + const std::vector &Entries = + MCOS->getContext().getMCGenDwarfLabelEntries(); + for (const auto &Entry : Entries) { // The DW_TAG_label DIE abbrev (2). MCOS->EmitULEB128IntValue(2); // AT_name, of the label without any leading underbar. - MCOS->EmitBytes(Entry->getName()); + MCOS->EmitBytes(Entry.getName()); MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string. // AT_decl_file, index into the file table. - MCOS->EmitIntValue(Entry->getFileNumber(), 4); + MCOS->EmitIntValue(Entry.getFileNumber(), 4); // AT_decl_line, source line number. - MCOS->EmitIntValue(Entry->getLineNumber(), 4); + MCOS->EmitIntValue(Entry.getLineNumber(), 4); // AT_low_pc, start address of the label. - const MCExpr *AT_low_pc = MCSymbolRefExpr::Create(Entry->getLabel(), + const MCExpr *AT_low_pc = MCSymbolRefExpr::Create(Entry.getLabel(), MCSymbolRefExpr::VK_None, context); - MCOS->EmitAbsValue(AT_low_pc, AddrSize); + MCOS->EmitValue(AT_low_pc, AddrSize); // DW_AT_prototyped, a one byte flag value of 0 saying we have no prototype. MCOS->EmitIntValue(0, 1); @@ -706,14 +783,6 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS, // Add the NULL DIE terminating the DW_TAG_unspecified_parameters DIE's. MCOS->EmitIntValue(0, 1); } - // Deallocate the MCGenDwarfLabelEntry classes that saved away the info - // for the dwarf labels. - for (std::vector::const_iterator it = - Entries.begin(), ie = Entries.end(); it != ie; - ++it) { - const MCGenDwarfLabelEntry *Entry = *it; - delete Entry; - } // Add the NULL DIE terminating the Compile Unit DIE's. MCOS->EmitIntValue(0, 1); @@ -722,20 +791,76 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS, MCOS->EmitLabel(InfoEnd); } +// When generating dwarf for assembly source files this emits the data for +// .debug_ranges section. We only emit one range list, which spans all of the +// executable sections of this file. +static void EmitGenDwarfRanges(MCStreamer *MCOS) { + MCContext &context = MCOS->getContext(); + auto &Sections = context.getGenDwarfSectionSyms(); + + const MCAsmInfo *AsmInfo = context.getAsmInfo(); + int AddrSize = AsmInfo->getPointerSize(); + + MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfRangesSection()); + + for (const auto &sec : Sections) { + + MCSymbol *StartSymbol = sec.second.first; + MCSymbol *EndSymbol = sec.second.second; + assert(StartSymbol && "StartSymbol must not be NULL"); + assert(EndSymbol && "EndSymbol must not be NULL"); + + // Emit a base address selection entry for the start of this section + const MCExpr *SectionStartAddr = MCSymbolRefExpr::Create( + StartSymbol, MCSymbolRefExpr::VK_None, context); + MCOS->EmitFill(AddrSize, 0xFF); + MCOS->EmitValue(SectionStartAddr, AddrSize); + + // Emit a range list entry spanning this section + const MCExpr *SectionSize = MakeStartMinusEndExpr(*MCOS, + *StartSymbol, *EndSymbol, 0); + MCOS->EmitIntValue(0, AddrSize); + emitAbsValue(*MCOS, SectionSize, AddrSize); + } + + // Emit end of list entry + MCOS->EmitIntValue(0, AddrSize); + MCOS->EmitIntValue(0, AddrSize); +} + // // When generating dwarf for assembly source files this emits the Dwarf // sections. // -void MCGenDwarfInfo::Emit(MCStreamer *MCOS, const MCSymbol *LineSectionSymbol) { - // Create the dwarf sections in this order (.debug_line already created). +void MCGenDwarfInfo::Emit(MCStreamer *MCOS) { MCContext &context = MCOS->getContext(); + + // Create the dwarf sections in this order (.debug_line already created). const MCAsmInfo *AsmInfo = context.getAsmInfo(); bool CreateDwarfSectionSymbols = AsmInfo->doesDwarfUseRelocationsAcrossSections(); - if (!CreateDwarfSectionSymbols) - LineSectionSymbol = NULL; - MCSymbol *AbbrevSectionSymbol = NULL; - MCSymbol *InfoSectionSymbol = NULL; + MCSymbol *LineSectionSymbol = nullptr; + if (CreateDwarfSectionSymbols) + LineSectionSymbol = MCOS->getDwarfLineTableSymbol(0); + MCSymbol *AbbrevSectionSymbol = nullptr; + MCSymbol *InfoSectionSymbol = nullptr; + MCSymbol *RangesSectionSymbol = NULL; + + // Create end symbols for each section, and remove empty sections + MCOS->getContext().finalizeDwarfSections(*MCOS); + + // If there are no sections to generate debug info for, we don't need + // to do anything + if (MCOS->getContext().getGenDwarfSectionSyms().empty()) + return; + + // We only use the .debug_ranges section if we have multiple code sections, + // and we are emitting a DWARF version which supports it. + const bool UseRangesSection = + MCOS->getContext().getGenDwarfSectionSyms().size() > 1 && + MCOS->getContext().getDwarfVersion() >= 3; + CreateDwarfSectionSymbols |= UseRangesSection; + MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfInfoSection()); if (CreateDwarfSectionSymbols) { InfoSectionSymbol = context.CreateTempSymbol(); @@ -746,20 +871,30 @@ void MCGenDwarfInfo::Emit(MCStreamer *MCOS, const MCSymbol *LineSectionSymbol) { AbbrevSectionSymbol = context.CreateTempSymbol(); MCOS->EmitLabel(AbbrevSectionSymbol); } - MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfARangesSection()); + if (UseRangesSection) { + MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfRangesSection()); + if (CreateDwarfSectionSymbols) { + RangesSectionSymbol = context.CreateTempSymbol(); + MCOS->EmitLabel(RangesSectionSymbol); + } + } - // If there are no line table entries then do not emit any section contents. - if (context.getMCLineSections().empty()) - return; + assert((RangesSectionSymbol != NULL) || !UseRangesSection); + + MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfARangesSection()); // Output the data for .debug_aranges section. EmitGenDwarfAranges(MCOS, InfoSectionSymbol); + if (UseRangesSection) + EmitGenDwarfRanges(MCOS); + // Output the data for .debug_abbrev section. EmitGenDwarfAbbrev(MCOS); // Output the data for .debug_info section. - EmitGenDwarfInfo(MCOS, AbbrevSectionSymbol, LineSectionSymbol); + EmitGenDwarfInfo(MCOS, AbbrevSectionSymbol, LineSectionSymbol, + RangesSectionSymbol); } // @@ -770,12 +905,13 @@ void MCGenDwarfInfo::Emit(MCStreamer *MCOS, const MCSymbol *LineSectionSymbol) { // void MCGenDwarfLabelEntry::Make(MCSymbol *Symbol, MCStreamer *MCOS, SourceMgr &SrcMgr, SMLoc &Loc) { - // We won't create dwarf labels for temporary symbols or symbols not in - // the default text. + // We won't create dwarf labels for temporary symbols. if (Symbol->isTemporary()) return; MCContext &context = MCOS->getContext(); - if (context.getGenDwarfSection() != MCOS->getCurrentSection().first) + // We won't create dwarf labels for symbols in sections that we are not + // generating debug info for. + if (!context.getGenDwarfSectionSyms().count(MCOS->getCurrentSection().first)) return; // The dwarf label's name does not have the symbol name's leading @@ -789,7 +925,7 @@ void MCGenDwarfLabelEntry::Make(MCSymbol *Symbol, MCStreamer *MCOS, // Finding the line number is the expensive part which is why we just don't // pass it in as for some symbols we won't create a dwarf label. - int CurBuffer = SrcMgr.FindBufferContainingLoc(Loc); + unsigned CurBuffer = SrcMgr.FindBufferContainingLoc(Loc); unsigned LineNumber = SrcMgr.FindLineNumber(Loc, CurBuffer); // We create a temporary symbol for use for the AT_high_pc and AT_low_pc @@ -800,9 +936,8 @@ void MCGenDwarfLabelEntry::Make(MCSymbol *Symbol, MCStreamer *MCOS, MCOS->EmitLabel(Label); // Create and entry for the info and add it to the other entries. - MCGenDwarfLabelEntry *Entry = - new MCGenDwarfLabelEntry(Name, FileNumber, LineNumber, Label); - MCOS->getContext().addMCGenDwarfLabelEntry(Entry); + MCOS->getContext().addMCGenDwarfLabelEntry( + MCGenDwarfLabelEntry(Name, FileNumber, LineNumber, Label)); } static int getDataAlignmentFactor(MCStreamer &streamer) { @@ -836,16 +971,18 @@ static unsigned getSizeForEncoding(MCStreamer &streamer, } } -static void EmitSymbol(MCStreamer &streamer, const MCSymbol &symbol, - unsigned symbolEncoding, const char *comment = 0) { +static void emitFDESymbol(MCObjectStreamer &streamer, const MCSymbol &symbol, + unsigned symbolEncoding, bool isEH) { MCContext &context = streamer.getContext(); const MCAsmInfo *asmInfo = context.getAsmInfo(); const MCExpr *v = asmInfo->getExprForFDESymbol(&symbol, symbolEncoding, streamer); unsigned size = getSizeForEncoding(streamer, symbolEncoding); - if (streamer.isVerboseAsm() && comment) streamer.AddComment(comment); - streamer.EmitAbsValue(v, size); + if (asmInfo->doDwarfFDESymbolsUseAbsDiff() && isEH) + emitAbsValue(streamer, v, size); + else + streamer.EmitValue(v, size); } static void EmitPersonality(MCStreamer &streamer, const MCSymbol &symbol, @@ -862,111 +999,67 @@ static void EmitPersonality(MCStreamer &streamer, const MCSymbol &symbol, namespace { class FrameEmitterImpl { int CFAOffset; - int CIENum; - bool UsingCFI; + int InitialCFAOffset; bool IsEH; const MCSymbol *SectionStart; public: - FrameEmitterImpl(bool usingCFI, bool isEH) - : CFAOffset(0), CIENum(0), UsingCFI(usingCFI), IsEH(isEH), - SectionStart(0) {} + FrameEmitterImpl(bool isEH) + : CFAOffset(0), InitialCFAOffset(0), IsEH(isEH), SectionStart(nullptr) { + } void setSectionStart(const MCSymbol *Label) { SectionStart = Label; } - /// EmitCompactUnwind - Emit the unwind information in a compact way. If - /// we're successful, return 'true'. Otherwise, return 'false' and it will - /// emit the normal CIE and FDE. - void EmitCompactUnwind(MCStreamer &streamer, + /// Emit the unwind information in a compact way. + void EmitCompactUnwind(MCObjectStreamer &streamer, const MCDwarfFrameInfo &frame); - const MCSymbol &EmitCIE(MCStreamer &streamer, + const MCSymbol &EmitCIE(MCObjectStreamer &streamer, const MCSymbol *personality, unsigned personalityEncoding, const MCSymbol *lsda, bool IsSignalFrame, - unsigned lsdaEncoding); - MCSymbol *EmitFDE(MCStreamer &streamer, + unsigned lsdaEncoding, + bool IsSimple); + MCSymbol *EmitFDE(MCObjectStreamer &streamer, const MCSymbol &cieStart, const MCDwarfFrameInfo &frame); - void EmitCFIInstructions(MCStreamer &streamer, - const std::vector &Instrs, + void EmitCFIInstructions(MCObjectStreamer &streamer, + ArrayRef Instrs, MCSymbol *BaseLabel); - void EmitCFIInstruction(MCStreamer &Streamer, + void EmitCFIInstruction(MCObjectStreamer &Streamer, const MCCFIInstruction &Instr); }; } // end anonymous namespace -static void EmitEncodingByte(MCStreamer &Streamer, unsigned Encoding, - StringRef Prefix) { - if (Streamer.isVerboseAsm()) { - const char *EncStr; - switch (Encoding) { - default: EncStr = ""; break; - case dwarf::DW_EH_PE_absptr: EncStr = "absptr"; break; - case dwarf::DW_EH_PE_omit: EncStr = "omit"; break; - case dwarf::DW_EH_PE_pcrel: EncStr = "pcrel"; break; - case dwarf::DW_EH_PE_udata4: EncStr = "udata4"; break; - case dwarf::DW_EH_PE_udata8: EncStr = "udata8"; break; - case dwarf::DW_EH_PE_sdata4: EncStr = "sdata4"; break; - case dwarf::DW_EH_PE_sdata8: EncStr = "sdata8"; break; - case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4: - EncStr = "pcrel udata4"; - break; - case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4: - EncStr = "pcrel sdata4"; - break; - case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8: - EncStr = "pcrel udata8"; - break; - case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8: - EncStr = "screl sdata8"; - break; - case dwarf::DW_EH_PE_indirect |dwarf::DW_EH_PE_pcrel|dwarf::DW_EH_PE_udata4: - EncStr = "indirect pcrel udata4"; - break; - case dwarf::DW_EH_PE_indirect |dwarf::DW_EH_PE_pcrel|dwarf::DW_EH_PE_sdata4: - EncStr = "indirect pcrel sdata4"; - break; - case dwarf::DW_EH_PE_indirect |dwarf::DW_EH_PE_pcrel|dwarf::DW_EH_PE_udata8: - EncStr = "indirect pcrel udata8"; - break; - case dwarf::DW_EH_PE_indirect |dwarf::DW_EH_PE_pcrel|dwarf::DW_EH_PE_sdata8: - EncStr = "indirect pcrel sdata8"; - break; - } - - Streamer.AddComment(Twine(Prefix) + " = " + EncStr); - } - +static void emitEncodingByte(MCObjectStreamer &Streamer, unsigned Encoding) { Streamer.EmitIntValue(Encoding, 1); } -void FrameEmitterImpl::EmitCFIInstruction(MCStreamer &Streamer, +void FrameEmitterImpl::EmitCFIInstruction(MCObjectStreamer &Streamer, const MCCFIInstruction &Instr) { int dataAlignmentFactor = getDataAlignmentFactor(Streamer); - bool VerboseAsm = Streamer.isVerboseAsm(); + auto *MRI = Streamer.getContext().getRegisterInfo(); switch (Instr.getOperation()) { case MCCFIInstruction::OpRegister: { unsigned Reg1 = Instr.getRegister(); unsigned Reg2 = Instr.getRegister2(); - if (VerboseAsm) { - Streamer.AddComment("DW_CFA_register"); - Streamer.AddComment(Twine("Reg1 ") + Twine(Reg1)); - Streamer.AddComment(Twine("Reg2 ") + Twine(Reg2)); + if (!IsEH) { + Reg1 = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg1, true), false); + Reg2 = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg2, true), false); } Streamer.EmitIntValue(dwarf::DW_CFA_register, 1); Streamer.EmitULEB128IntValue(Reg1); Streamer.EmitULEB128IntValue(Reg2); return; } + case MCCFIInstruction::OpWindowSave: { + Streamer.EmitIntValue(dwarf::DW_CFA_GNU_window_save, 1); + return; + } case MCCFIInstruction::OpUndefined: { unsigned Reg = Instr.getRegister(); - if (VerboseAsm) { - Streamer.AddComment("DW_CFA_undefined"); - Streamer.AddComment(Twine("Reg ") + Twine(Reg)); - } Streamer.EmitIntValue(dwarf::DW_CFA_undefined, 1); Streamer.EmitULEB128IntValue(Reg); return; @@ -976,8 +1069,6 @@ void FrameEmitterImpl::EmitCFIInstruction(MCStreamer &Streamer, const bool IsRelative = Instr.getOperation() == MCCFIInstruction::OpAdjustCfaOffset; - if (VerboseAsm) - Streamer.AddComment("DW_CFA_def_cfa_offset"); Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa_offset, 1); if (IsRelative) @@ -985,38 +1076,28 @@ void FrameEmitterImpl::EmitCFIInstruction(MCStreamer &Streamer, else CFAOffset = -Instr.getOffset(); - if (VerboseAsm) - Streamer.AddComment(Twine("Offset " + Twine(CFAOffset))); Streamer.EmitULEB128IntValue(CFAOffset); return; } case MCCFIInstruction::OpDefCfa: { - if (VerboseAsm) - Streamer.AddComment("DW_CFA_def_cfa"); + unsigned Reg = Instr.getRegister(); + if (!IsEH) + Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false); Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa, 1); - - if (VerboseAsm) - Streamer.AddComment(Twine("Reg ") + Twine(Instr.getRegister())); - Streamer.EmitULEB128IntValue(Instr.getRegister()); - + Streamer.EmitULEB128IntValue(Reg); CFAOffset = -Instr.getOffset(); - - if (VerboseAsm) - Streamer.AddComment(Twine("Offset " + Twine(CFAOffset))); Streamer.EmitULEB128IntValue(CFAOffset); return; } case MCCFIInstruction::OpDefCfaRegister: { - if (VerboseAsm) - Streamer.AddComment("DW_CFA_def_cfa_register"); + unsigned Reg = Instr.getRegister(); + if (!IsEH) + Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false); Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa_register, 1); - - if (VerboseAsm) - Streamer.AddComment(Twine("Reg ") + Twine(Instr.getRegister())); - Streamer.EmitULEB128IntValue(Instr.getRegister()); + Streamer.EmitULEB128IntValue(Reg); return; } @@ -1027,71 +1108,57 @@ void FrameEmitterImpl::EmitCFIInstruction(MCStreamer &Streamer, Instr.getOperation() == MCCFIInstruction::OpRelOffset; unsigned Reg = Instr.getRegister(); + if (!IsEH) + Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false); + int Offset = Instr.getOffset(); if (IsRelative) Offset -= CFAOffset; Offset = Offset / dataAlignmentFactor; if (Offset < 0) { - if (VerboseAsm) Streamer.AddComment("DW_CFA_offset_extended_sf"); Streamer.EmitIntValue(dwarf::DW_CFA_offset_extended_sf, 1); - if (VerboseAsm) Streamer.AddComment(Twine("Reg ") + Twine(Reg)); Streamer.EmitULEB128IntValue(Reg); - if (VerboseAsm) Streamer.AddComment(Twine("Offset ") + Twine(Offset)); Streamer.EmitSLEB128IntValue(Offset); } else if (Reg < 64) { - if (VerboseAsm) Streamer.AddComment(Twine("DW_CFA_offset + Reg(") + - Twine(Reg) + ")"); Streamer.EmitIntValue(dwarf::DW_CFA_offset + Reg, 1); - if (VerboseAsm) Streamer.AddComment(Twine("Offset ") + Twine(Offset)); Streamer.EmitULEB128IntValue(Offset); } else { - if (VerboseAsm) Streamer.AddComment("DW_CFA_offset_extended"); Streamer.EmitIntValue(dwarf::DW_CFA_offset_extended, 1); - if (VerboseAsm) Streamer.AddComment(Twine("Reg ") + Twine(Reg)); Streamer.EmitULEB128IntValue(Reg); - if (VerboseAsm) Streamer.AddComment(Twine("Offset ") + Twine(Offset)); Streamer.EmitULEB128IntValue(Offset); } return; } case MCCFIInstruction::OpRememberState: - if (VerboseAsm) Streamer.AddComment("DW_CFA_remember_state"); Streamer.EmitIntValue(dwarf::DW_CFA_remember_state, 1); return; case MCCFIInstruction::OpRestoreState: - if (VerboseAsm) Streamer.AddComment("DW_CFA_restore_state"); Streamer.EmitIntValue(dwarf::DW_CFA_restore_state, 1); return; case MCCFIInstruction::OpSameValue: { unsigned Reg = Instr.getRegister(); - if (VerboseAsm) Streamer.AddComment("DW_CFA_same_value"); Streamer.EmitIntValue(dwarf::DW_CFA_same_value, 1); - if (VerboseAsm) Streamer.AddComment(Twine("Reg ") + Twine(Reg)); Streamer.EmitULEB128IntValue(Reg); return; } case MCCFIInstruction::OpRestore: { unsigned Reg = Instr.getRegister(); - if (VerboseAsm) { - Streamer.AddComment("DW_CFA_restore"); - Streamer.AddComment(Twine("Reg ") + Twine(Reg)); - } + if (!IsEH) + Reg = MRI->getDwarfRegNum(MRI->getLLVMRegNum(Reg, true), false); Streamer.EmitIntValue(dwarf::DW_CFA_restore | Reg, 1); return; } case MCCFIInstruction::OpEscape: - if (VerboseAsm) Streamer.AddComment("Escape bytes"); Streamer.EmitBytes(Instr.getValues()); return; } llvm_unreachable("Unhandled case in switch"); } -/// EmitFrameMoves - Emit frame instructions to describe the layout of the -/// frame. -void FrameEmitterImpl::EmitCFIInstructions(MCStreamer &streamer, - const std::vector &Instrs, +/// Emit frame instructions to describe the layout of the frame. +void FrameEmitterImpl::EmitCFIInstructions(MCObjectStreamer &streamer, + ArrayRef Instrs, MCSymbol *BaseLabel) { for (unsigned i = 0, N = Instrs.size(); i < N; ++i) { const MCCFIInstruction &Instr = Instrs[i]; @@ -1103,7 +1170,6 @@ void FrameEmitterImpl::EmitCFIInstructions(MCStreamer &streamer, if (BaseLabel && Label) { MCSymbol *ThisSym = Label; if (ThisSym != BaseLabel) { - if (streamer.isVerboseAsm()) streamer.AddComment("DW_CFA_advance_loc4"); streamer.EmitDwarfAdvanceFrameAddr(BaseLabel, ThisSym); BaseLabel = ThisSym; } @@ -1113,14 +1179,11 @@ void FrameEmitterImpl::EmitCFIInstructions(MCStreamer &streamer, } } -/// EmitCompactUnwind - Emit the unwind information in a compact way. If we're -/// successful, return 'true'. Otherwise, return 'false' and it will emit the -/// normal CIE and FDE. -void FrameEmitterImpl::EmitCompactUnwind(MCStreamer &Streamer, +/// Emit the unwind information in a compact way. +void FrameEmitterImpl::EmitCompactUnwind(MCObjectStreamer &Streamer, const MCDwarfFrameInfo &Frame) { MCContext &Context = Streamer.getContext(); const MCObjectFileInfo *MOFI = Context.getObjectFileInfo(); - bool VerboseAsm = Streamer.isVerboseAsm(); // range-start range-length compact-unwind-enc personality-func lsda // _foo LfooEnd-_foo 0x00000023 0 0 @@ -1153,26 +1216,21 @@ void FrameEmitterImpl::EmitCompactUnwind(MCStreamer &Streamer, Encoding |= 0x40000000; // Range Start - unsigned FDEEncoding = MOFI->getFDEEncoding(UsingCFI); + unsigned FDEEncoding = MOFI->getFDEEncoding(); unsigned Size = getSizeForEncoding(Streamer, FDEEncoding); - if (VerboseAsm) Streamer.AddComment("Range Start"); - Streamer.EmitSymbolValue(Frame.Function, Size); + Streamer.EmitSymbolValue(Frame.Begin, Size); // Range Length const MCExpr *Range = MakeStartMinusEndExpr(Streamer, *Frame.Begin, *Frame.End, 0); - if (VerboseAsm) Streamer.AddComment("Range Length"); - Streamer.EmitAbsValue(Range, 4); + emitAbsValue(Streamer, Range, 4); // Compact Encoding Size = getSizeForEncoding(Streamer, dwarf::DW_EH_PE_udata4); - if (VerboseAsm) Streamer.AddComment("Compact Unwind Encoding: 0x" + - Twine::utohexstr(Encoding)); Streamer.EmitIntValue(Encoding, Size); // Personality Function Size = getSizeForEncoding(Streamer, dwarf::DW_EH_PE_absptr); - if (VerboseAsm) Streamer.AddComment("Personality Function"); if (!DwarfEHFrameOnly && Frame.Personality) Streamer.EmitSymbolValue(Frame.Personality, Size); else @@ -1180,54 +1238,58 @@ void FrameEmitterImpl::EmitCompactUnwind(MCStreamer &Streamer, // LSDA Size = getSizeForEncoding(Streamer, Frame.LsdaEncoding); - if (VerboseAsm) Streamer.AddComment("LSDA"); if (!DwarfEHFrameOnly && Frame.Lsda) Streamer.EmitSymbolValue(Frame.Lsda, Size); else Streamer.EmitIntValue(0, Size); // No LSDA } -const MCSymbol &FrameEmitterImpl::EmitCIE(MCStreamer &streamer, +static unsigned getCIEVersion(bool IsEH, unsigned DwarfVersion) { + if (IsEH) + return 1; + switch (DwarfVersion) { + case 2: + return 1; + case 3: + return 3; + case 4: + return 4; + } + llvm_unreachable("Unknown version"); +} + +const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer, const MCSymbol *personality, unsigned personalityEncoding, const MCSymbol *lsda, bool IsSignalFrame, - unsigned lsdaEncoding) { + unsigned lsdaEncoding, + bool IsSimple) { MCContext &context = streamer.getContext(); const MCRegisterInfo *MRI = context.getRegisterInfo(); const MCObjectFileInfo *MOFI = context.getObjectFileInfo(); - bool verboseAsm = streamer.isVerboseAsm(); - - MCSymbol *sectionStart; - if (MOFI->isFunctionEHFrameSymbolPrivate() || !IsEH) - sectionStart = context.CreateTempSymbol(); - else - sectionStart = context.GetOrCreateSymbol(Twine("EH_frame") + Twine(CIENum)); + MCSymbol *sectionStart = context.CreateTempSymbol(); streamer.EmitLabel(sectionStart); - CIENum++; MCSymbol *sectionEnd = context.CreateTempSymbol(); // Length const MCExpr *Length = MakeStartMinusEndExpr(streamer, *sectionStart, *sectionEnd, 4); - if (verboseAsm) streamer.AddComment("CIE Length"); - streamer.EmitAbsValue(Length, 4); + emitAbsValue(streamer, Length, 4); // CIE ID unsigned CIE_ID = IsEH ? 0 : -1; - if (verboseAsm) streamer.AddComment("CIE ID Tag"); streamer.EmitIntValue(CIE_ID, 4); // Version - if (verboseAsm) streamer.AddComment("DW_CIE_VERSION"); - streamer.EmitIntValue(dwarf::DW_CIE_VERSION, 1); + uint8_t CIEVersion = getCIEVersion(IsEH, context.getDwarfVersion()); + streamer.EmitIntValue(CIEVersion, 1); // Augmentation String SmallString<8> Augmentation; if (IsEH) { - if (verboseAsm) streamer.AddComment("CIE Augmentation"); Augmentation += "z"; if (personality) Augmentation += "P"; @@ -1236,21 +1298,33 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCStreamer &streamer, Augmentation += "R"; if (IsSignalFrame) Augmentation += "S"; - streamer.EmitBytes(Augmentation.str()); + streamer.EmitBytes(Augmentation); } streamer.EmitIntValue(0, 1); + if (CIEVersion >= 4) { + // Address Size + streamer.EmitIntValue(context.getAsmInfo()->getPointerSize(), 1); + + // Segment Descriptor Size + streamer.EmitIntValue(0, 1); + } + // Code Alignment Factor - if (verboseAsm) streamer.AddComment("CIE Code Alignment Factor"); streamer.EmitULEB128IntValue(context.getAsmInfo()->getMinInstAlignment()); // Data Alignment Factor - if (verboseAsm) streamer.AddComment("CIE Data Alignment Factor"); streamer.EmitSLEB128IntValue(getDataAlignmentFactor(streamer)); // Return Address Register - if (verboseAsm) streamer.AddComment("CIE Return Address Column"); - streamer.EmitULEB128IntValue(MRI->getDwarfRegNum(MRI->getRARegister(), true)); + if (CIEVersion == 1) { + assert(MRI->getRARegister() <= 255 && + "DWARF 2 encodes return_address_register in one byte"); + streamer.EmitIntValue(MRI->getDwarfRegNum(MRI->getRARegister(), IsEH), 1); + } else { + streamer.EmitULEB128IntValue( + MRI->getDwarfRegNum(MRI->getRARegister(), IsEH)); + } // Augmentation Data Length (optional) @@ -1267,33 +1341,33 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCStreamer &streamer, // Encoding of the FDE pointers augmentationLength += 1; - if (verboseAsm) streamer.AddComment("Augmentation Size"); streamer.EmitULEB128IntValue(augmentationLength); // Augmentation Data (optional) if (personality) { // Personality Encoding - EmitEncodingByte(streamer, personalityEncoding, - "Personality Encoding"); + emitEncodingByte(streamer, personalityEncoding); // Personality - if (verboseAsm) streamer.AddComment("Personality"); EmitPersonality(streamer, *personality, personalityEncoding); } if (lsda) - EmitEncodingByte(streamer, lsdaEncoding, "LSDA Encoding"); + emitEncodingByte(streamer, lsdaEncoding); // Encoding of the FDE pointers - EmitEncodingByte(streamer, MOFI->getFDEEncoding(UsingCFI), - "FDE Encoding"); + emitEncodingByte(streamer, MOFI->getFDEEncoding()); } // Initial Instructions const MCAsmInfo *MAI = context.getAsmInfo(); - const std::vector &Instructions = - MAI->getInitialFrameState(); - EmitCFIInstructions(streamer, Instructions, NULL); + if (!IsSimple) { + const std::vector &Instructions = + MAI->getInitialFrameState(); + EmitCFIInstructions(streamer, Instructions, nullptr); + } + + InitialCFAOffset = CFAOffset; // Padding streamer.EmitValueToAlignment(IsEH ? 4 : MAI->getPointerSize()); @@ -1302,26 +1376,19 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCStreamer &streamer, return *sectionStart; } -MCSymbol *FrameEmitterImpl::EmitFDE(MCStreamer &streamer, +MCSymbol *FrameEmitterImpl::EmitFDE(MCObjectStreamer &streamer, const MCSymbol &cieStart, const MCDwarfFrameInfo &frame) { MCContext &context = streamer.getContext(); MCSymbol *fdeStart = context.CreateTempSymbol(); MCSymbol *fdeEnd = context.CreateTempSymbol(); const MCObjectFileInfo *MOFI = context.getObjectFileInfo(); - bool verboseAsm = streamer.isVerboseAsm(); - if (IsEH && frame.Function && !MOFI->isFunctionEHFrameSymbolPrivate()) { - MCSymbol *EHSym = - context.GetOrCreateSymbol(frame.Function->getName() + Twine(".eh")); - streamer.EmitEHSymAttributes(frame.Function, EHSym); - streamer.EmitLabel(EHSym); - } + CFAOffset = InitialCFAOffset; // Length const MCExpr *Length = MakeStartMinusEndExpr(streamer, *fdeStart, *fdeEnd, 0); - if (verboseAsm) streamer.AddComment("FDE Length"); - streamer.EmitAbsValue(Length, 4); + emitAbsValue(streamer, Length, 4); streamer.EmitLabel(fdeStart); @@ -1330,27 +1397,25 @@ MCSymbol *FrameEmitterImpl::EmitFDE(MCStreamer &streamer, if (IsEH) { const MCExpr *offset = MakeStartMinusEndExpr(streamer, cieStart, *fdeStart, 0); - if (verboseAsm) streamer.AddComment("FDE CIE Offset"); - streamer.EmitAbsValue(offset, 4); + emitAbsValue(streamer, offset, 4); } else if (!asmInfo->doesDwarfUseRelocationsAcrossSections()) { const MCExpr *offset = MakeStartMinusEndExpr(streamer, *SectionStart, cieStart, 0); - streamer.EmitAbsValue(offset, 4); + emitAbsValue(streamer, offset, 4); } else { streamer.EmitSymbolValue(&cieStart, 4); } // PC Begin - unsigned PCEncoding = IsEH ? MOFI->getFDEEncoding(UsingCFI) - : (unsigned)dwarf::DW_EH_PE_absptr; + unsigned PCEncoding = + IsEH ? MOFI->getFDEEncoding() : (unsigned)dwarf::DW_EH_PE_absptr; unsigned PCSize = getSizeForEncoding(streamer, PCEncoding); - EmitSymbol(streamer, *frame.Begin, PCEncoding, "FDE initial location"); + emitFDESymbol(streamer, *frame.Begin, PCEncoding, IsEH); // PC Range const MCExpr *Range = MakeStartMinusEndExpr(streamer, *frame.Begin, *frame.End, 0); - if (verboseAsm) streamer.AddComment("FDE address range"); - streamer.EmitAbsValue(Range, PCSize); + emitAbsValue(streamer, Range, PCSize); if (IsEH) { // Augmentation Data Length @@ -1359,13 +1424,11 @@ MCSymbol *FrameEmitterImpl::EmitFDE(MCStreamer &streamer, if (frame.Lsda) augmentationLength += getSizeForEncoding(streamer, frame.LsdaEncoding); - if (verboseAsm) streamer.AddComment("Augmentation size"); streamer.EmitULEB128IntValue(augmentationLength); // Augmentation Data if (frame.Lsda) - EmitSymbol(streamer, *frame.Lsda, frame.LsdaEncoding, - "Language Specific Data Area"); + emitFDESymbol(streamer, *frame.Lsda, frame.LsdaEncoding, true); } // Call Frame Instructions @@ -1379,18 +1442,23 @@ MCSymbol *FrameEmitterImpl::EmitFDE(MCStreamer &streamer, namespace { struct CIEKey { - static const CIEKey getEmptyKey() { return CIEKey(0, 0, -1, false); } - static const CIEKey getTombstoneKey() { return CIEKey(0, -1, 0, false); } - - CIEKey(const MCSymbol* Personality_, unsigned PersonalityEncoding_, - unsigned LsdaEncoding_, bool IsSignalFrame_) : - Personality(Personality_), PersonalityEncoding(PersonalityEncoding_), - LsdaEncoding(LsdaEncoding_), IsSignalFrame(IsSignalFrame_) { + static const CIEKey getEmptyKey() { + return CIEKey(nullptr, 0, -1, false, false); } - const MCSymbol* Personality; + static const CIEKey getTombstoneKey() { + return CIEKey(nullptr, -1, 0, false, false); + } + + CIEKey(const MCSymbol *Personality_, unsigned PersonalityEncoding_, + unsigned LsdaEncoding_, bool IsSignalFrame_, bool IsSimple_) + : Personality(Personality_), PersonalityEncoding(PersonalityEncoding_), + LsdaEncoding(LsdaEncoding_), IsSignalFrame(IsSignalFrame_), + IsSimple(IsSimple_) {} + const MCSymbol *Personality; unsigned PersonalityEncoding; unsigned LsdaEncoding; bool IsSignalFrame; + bool IsSimple; }; } @@ -1407,27 +1475,31 @@ namespace llvm { return static_cast(hash_combine(Key.Personality, Key.PersonalityEncoding, Key.LsdaEncoding, - Key.IsSignalFrame)); + Key.IsSignalFrame, + Key.IsSimple)); } static bool isEqual(const CIEKey &LHS, const CIEKey &RHS) { return LHS.Personality == RHS.Personality && LHS.PersonalityEncoding == RHS.PersonalityEncoding && LHS.LsdaEncoding == RHS.LsdaEncoding && - LHS.IsSignalFrame == RHS.IsSignalFrame; + LHS.IsSignalFrame == RHS.IsSignalFrame && + LHS.IsSimple == RHS.IsSimple; } }; } -void MCDwarfFrameEmitter::Emit(MCStreamer &Streamer, - bool UsingCFI, +void MCDwarfFrameEmitter::Emit(MCObjectStreamer &Streamer, MCAsmBackend *MAB, bool IsEH) { + Streamer.generateCompactUnwindEncodings(MAB); + MCContext &Context = Streamer.getContext(); const MCObjectFileInfo *MOFI = Context.getObjectFileInfo(); - FrameEmitterImpl Emitter(UsingCFI, IsEH); - ArrayRef FrameArray = Streamer.getFrameInfos(); + FrameEmitterImpl Emitter(IsEH); + ArrayRef FrameArray = Streamer.getDwarfFrameInfos(); // Emit the compact unwind info if available. + bool NeedsEHFrameSection = !MOFI->getSupportsCompactUnwindWithoutEHFrame(); if (IsEH && MOFI->getCompactUnwindSection()) { bool SectionEmitted = false; for (unsigned i = 0, n = FrameArray.size(); i < n; ++i) { @@ -1438,37 +1510,55 @@ void MCDwarfFrameEmitter::Emit(MCStreamer &Streamer, Streamer.EmitValueToAlignment(Context.getAsmInfo()->getPointerSize()); SectionEmitted = true; } + NeedsEHFrameSection |= + Frame.CompactUnwindEncoding == + MOFI->getCompactUnwindDwarfEHFrameOnly(); Emitter.EmitCompactUnwind(Streamer, Frame); } } + if (!NeedsEHFrameSection) return; + const MCSection &Section = IsEH ? *const_cast(MOFI)->getEHFrameSection() : *MOFI->getDwarfFrameSection(); + Streamer.SwitchSection(&Section); MCSymbol *SectionStart = Context.CreateTempSymbol(); Streamer.EmitLabel(SectionStart); Emitter.setSectionStart(SectionStart); - MCSymbol *FDEEnd = NULL; - DenseMap CIEStarts; + MCSymbol *FDEEnd = nullptr; + DenseMap CIEStarts; - const MCSymbol *DummyDebugKey = NULL; + const MCSymbol *DummyDebugKey = nullptr; + NeedsEHFrameSection = !MOFI->getSupportsCompactUnwindWithoutEHFrame(); for (unsigned i = 0, n = FrameArray.size(); i < n; ++i) { const MCDwarfFrameInfo &Frame = FrameArray[i]; + + // Emit the label from the previous iteration + if (FDEEnd) { + Streamer.EmitLabel(FDEEnd); + FDEEnd = nullptr; + } + + if (!NeedsEHFrameSection && Frame.CompactUnwindEncoding != + MOFI->getCompactUnwindDwarfEHFrameOnly()) + // Don't generate an EH frame if we don't need one. I.e., it's taken care + // of by the compact unwind encoding. + continue; + CIEKey Key(Frame.Personality, Frame.PersonalityEncoding, - Frame.LsdaEncoding, Frame.IsSignalFrame); + Frame.LsdaEncoding, Frame.IsSignalFrame, Frame.IsSimple); const MCSymbol *&CIEStart = IsEH ? CIEStarts[Key] : DummyDebugKey; if (!CIEStart) CIEStart = &Emitter.EmitCIE(Streamer, Frame.Personality, Frame.PersonalityEncoding, Frame.Lsda, Frame.IsSignalFrame, - Frame.LsdaEncoding); + Frame.LsdaEncoding, + Frame.IsSimple); FDEEnd = Emitter.EmitFDE(Streamer, *CIEStart, Frame); - - if (i != n - 1) - Streamer.EmitLabel(FDEEnd); } Streamer.EmitValueToAlignment(Context.getAsmInfo()->getPointerSize()); @@ -1476,7 +1566,7 @@ void MCDwarfFrameEmitter::Emit(MCStreamer &Streamer, Streamer.EmitLabel(FDEEnd); } -void MCDwarfFrameEmitter::EmitAdvanceLoc(MCStreamer &Streamer, +void MCDwarfFrameEmitter::EmitAdvanceLoc(MCObjectStreamer &Streamer, uint64_t AddrDelta) { MCContext &Context = Streamer.getContext(); SmallString<256> Tmp;