//===- lib/MC/MCAsmStreamer.cpp - Text Assembly Output --------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #include "llvm/MC/MCStreamer.h" #include "llvm/ADT/SmallString.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/StringExtras.h" #include "llvm/ADT/Twine.h" #include "llvm/MC/MCAsmBackend.h" #include "llvm/MC/MCAsmInfo.h" #include "llvm/MC/MCCodeEmitter.h" #include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCFixupKindInfo.h" #include "llvm/MC/MCInst.h" #include "llvm/MC/MCInstPrinter.h" #include "llvm/MC/MCObjectFileInfo.h" #include "llvm/MC/MCRegisterInfo.h" #include "llvm/MC/MCSectionCOFF.h" #include "llvm/MC/MCSectionMachO.h" #include "llvm/MC/MCSymbol.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/Format.h" #include "llvm/Support/FormattedStream.h" #include "llvm/Support/MathExtras.h" #include "llvm/Support/Path.h" #include <cctype> #include <unordered_map> using namespace llvm; namespace { class MCAsmStreamer : public MCStreamer { protected: formatted_raw_ostream &OS; const MCAsmInfo *MAI; private: std::unique_ptr<MCInstPrinter> InstPrinter; std::unique_ptr<MCCodeEmitter> Emitter; std::unique_ptr<MCAsmBackend> AsmBackend; SmallString<128> CommentToEmit; raw_svector_ostream CommentStream; unsigned IsVerboseAsm : 1; unsigned ShowInst : 1; unsigned UseDwarfDirectory : 1; void EmitRegisterName(int64_t Register); void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) override; void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override; public: MCAsmStreamer(MCContext &Context, formatted_raw_ostream &os, bool isVerboseAsm, bool useDwarfDirectory, MCInstPrinter *printer, MCCodeEmitter *emitter, MCAsmBackend *asmbackend, bool showInst) : MCStreamer(Context), OS(os), MAI(Context.getAsmInfo()), InstPrinter(printer), Emitter(emitter), AsmBackend(asmbackend), CommentStream(CommentToEmit), IsVerboseAsm(isVerboseAsm), ShowInst(showInst), UseDwarfDirectory(useDwarfDirectory) { if (InstPrinter && IsVerboseAsm) InstPrinter->setCommentStream(CommentStream); } inline void EmitEOL() { // If we don't have any comments, just emit a \n. if (!IsVerboseAsm) { OS << '\n'; return; } EmitCommentsAndEOL(); } void EmitCommentsAndEOL(); /// isVerboseAsm - Return true if this streamer supports verbose assembly at /// all. bool isVerboseAsm() const override { return IsVerboseAsm; } /// hasRawTextSupport - We support EmitRawText. bool hasRawTextSupport() const override { return true; } /// AddComment - Add a comment that can be emitted to the generated .s /// file if applicable as a QoI issue to make the output of the compiler /// more readable. This only affects the MCAsmStreamer, and only when /// verbose assembly output is enabled. void AddComment(const Twine &T) override; /// AddEncodingComment - Add a comment showing the encoding of an instruction. void AddEncodingComment(const MCInst &Inst, const MCSubtargetInfo &); /// GetCommentOS - Return a raw_ostream that comments can be written to. /// Unlike AddComment, you are required to terminate comments with \n if you /// use this method. raw_ostream &GetCommentOS() override { if (!IsVerboseAsm) return nulls(); // Discard comments unless in verbose asm mode. return CommentStream; } void emitRawComment(const Twine &T, bool TabPrefix = true) override; /// AddBlankLine - Emit a blank line to a .s file to pretty it up. void AddBlankLine() override { EmitEOL(); } /// @name MCStreamer Interface /// @{ void ChangeSection(const MCSection *Section, const MCExpr *Subsection) override; void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) override; void EmitLabel(MCSymbol *Symbol) override; void EmitAssemblerFlag(MCAssemblerFlag Flag) override; void EmitLinkerOptions(ArrayRef<std::string> Options) override; void EmitDataRegion(MCDataRegionType Kind) override; void EmitVersionMin(MCVersionMinType Kind, unsigned Major, unsigned Minor, unsigned Update) override; void EmitThumbFunc(MCSymbol *Func) override; void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override; void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override; bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override; void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override; void BeginCOFFSymbolDef(const MCSymbol *Symbol) override; void EmitCOFFSymbolStorageClass(int StorageClass) override; void EmitCOFFSymbolType(int Type) override; void EndCOFFSymbolDef() override; void EmitCOFFSectionIndex(MCSymbol const *Symbol) override; void EmitCOFFSecRel32(MCSymbol const *Symbol) override; void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) override; void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment) override; /// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol. /// /// @param Symbol - The common symbol to emit. /// @param Size - The size of the common symbol. /// @param ByteAlignment - The alignment of the common symbol in bytes. void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment) override; void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = nullptr, uint64_t Size = 0, unsigned ByteAlignment = 0) override; void EmitTBSSSymbol (const MCSection *Section, MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment = 0) override; void EmitBytes(StringRef Data) override; void EmitValueImpl(const MCExpr *Value, unsigned Size, const SMLoc &Loc = SMLoc()) override; void EmitIntValue(uint64_t Value, unsigned Size) override; void EmitULEB128Value(const MCExpr *Value) override; void EmitSLEB128Value(const MCExpr *Value) override; void EmitGPRel64Value(const MCExpr *Value) override; void EmitGPRel32Value(const MCExpr *Value) override; void EmitFill(uint64_t NumBytes, uint8_t FillValue) override; void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0, unsigned ValueSize = 1, unsigned MaxBytesToEmit = 0) override; void EmitCodeAlignment(unsigned ByteAlignment, unsigned MaxBytesToEmit = 0) override; bool EmitValueToOffset(const MCExpr *Offset, unsigned char Value = 0) override; void EmitFileDirective(StringRef Filename) override; unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory, StringRef Filename, unsigned CUID = 0) override; void EmitDwarfLocDirective(unsigned FileNo, unsigned Line, unsigned Column, unsigned Flags, unsigned Isa, unsigned Discriminator, StringRef FileName) override; MCSymbol *getDwarfLineTableSymbol(unsigned CUID) override; void EmitIdent(StringRef IdentString) override; void EmitCFISections(bool EH, bool Debug) override; void EmitCFIDefCfa(int64_t Register, int64_t Offset) override; void EmitCFIDefCfaOffset(int64_t Offset) override; void EmitCFIDefCfaRegister(int64_t Register) override; void EmitCFIOffset(int64_t Register, int64_t Offset) override; void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding) override; void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) override; void EmitCFIRememberState() override; void EmitCFIRestoreState() override; void EmitCFISameValue(int64_t Register) override; void EmitCFIRelOffset(int64_t Register, int64_t Offset) override; void EmitCFIAdjustCfaOffset(int64_t Adjustment) override; void EmitCFISignalFrame() override; void EmitCFIUndefined(int64_t Register) override; void EmitCFIRegister(int64_t Register1, int64_t Register2) override; void EmitCFIWindowSave() override; void EmitWinCFIStartProc(const MCSymbol *Symbol) override; void EmitWinCFIEndProc() override; void EmitWinCFIStartChained() override; void EmitWinCFIEndChained() override; void EmitWinCFIPushReg(unsigned Register) override; void EmitWinCFISetFrame(unsigned Register, unsigned Offset) override; void EmitWinCFIAllocStack(unsigned Size) override; void EmitWinCFISaveReg(unsigned Register, unsigned Offset) override; void EmitWinCFISaveXMM(unsigned Register, unsigned Offset) override; void EmitWinCFIPushFrame(bool Code) override; void EmitWinCFIEndProlog() override; void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except) override; void EmitWinEHHandlerData() override; void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override; void EmitBundleAlignMode(unsigned AlignPow2) override; void EmitBundleLock(bool AlignToEnd) override; void EmitBundleUnlock() override; /// EmitRawText - If this file is backed by an assembly streamer, this dumps /// the specified string in the output .s file. This capability is /// indicated by the hasRawTextSupport() predicate. void EmitRawTextImpl(StringRef String) override; void FinishImpl() override; }; } // end anonymous namespace. /// AddComment - Add a comment that can be emitted to the generated .s /// file if applicable as a QoI issue to make the output of the compiler /// more readable. This only affects the MCAsmStreamer, and only when /// verbose assembly output is enabled. void MCAsmStreamer::AddComment(const Twine &T) { if (!IsVerboseAsm) return; // Make sure that CommentStream is flushed. CommentStream.flush(); T.toVector(CommentToEmit); // Each comment goes on its own line. CommentToEmit.push_back('\n'); // Tell the comment stream that the vector changed underneath it. CommentStream.resync(); } void MCAsmStreamer::EmitCommentsAndEOL() { if (CommentToEmit.empty() && CommentStream.GetNumBytesInBuffer() == 0) { OS << '\n'; return; } CommentStream.flush(); StringRef Comments = CommentToEmit.str(); assert(Comments.back() == '\n' && "Comment array not newline terminated"); do { // Emit a line of comments. OS.PadToColumn(MAI->getCommentColumn()); size_t Position = Comments.find('\n'); OS << MAI->getCommentString() << ' ' << Comments.substr(0, Position) <<'\n'; Comments = Comments.substr(Position+1); } while (!Comments.empty()); CommentToEmit.clear(); // Tell the comment stream that the vector changed underneath it. CommentStream.resync(); } static inline int64_t truncateToSize(int64_t Value, unsigned Bytes) { assert(Bytes && "Invalid size!"); return Value & ((uint64_t) (int64_t) -1 >> (64 - Bytes * 8)); } void MCAsmStreamer::emitRawComment(const Twine &T, bool TabPrefix) { if (TabPrefix) OS << '\t'; OS << MAI->getCommentString() << T; EmitEOL(); } void MCAsmStreamer::ChangeSection(const MCSection *Section, const MCExpr *Subsection) { assert(Section && "Cannot switch to a null section!"); Section->PrintSwitchToSection(*MAI, OS, Subsection); } void MCAsmStreamer::EmitLabel(MCSymbol *Symbol) { assert(Symbol->isUndefined() && "Cannot define a symbol twice!"); MCStreamer::EmitLabel(Symbol); OS << *Symbol << MAI->getLabelSuffix(); EmitEOL(); } void MCAsmStreamer::EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) { StringRef str = MCLOHIdToName(Kind); #ifndef NDEBUG int NbArgs = MCLOHIdToNbArgs(Kind); assert(NbArgs != -1 && ((size_t)NbArgs) == Args.size() && "Malformed LOH!"); assert(str != "" && "Invalid LOH name"); #endif OS << "\t" << MCLOHDirectiveName() << " " << str << "\t"; bool IsFirst = true; for (MCLOHArgs::const_iterator It = Args.begin(), EndIt = Args.end(); It != EndIt; ++It) { if (!IsFirst) OS << ", "; IsFirst = false; OS << **It; } EmitEOL(); } void MCAsmStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) { switch (Flag) { case MCAF_SyntaxUnified: OS << "\t.syntax unified"; break; case MCAF_SubsectionsViaSymbols: OS << ".subsections_via_symbols"; break; case MCAF_Code16: OS << '\t'<< MAI->getCode16Directive();break; case MCAF_Code32: OS << '\t'<< MAI->getCode32Directive();break; case MCAF_Code64: OS << '\t'<< MAI->getCode64Directive();break; } EmitEOL(); } void MCAsmStreamer::EmitLinkerOptions(ArrayRef<std::string> Options) { assert(!Options.empty() && "At least one option is required!"); OS << "\t.linker_option \"" << Options[0] << '"'; for (ArrayRef<std::string>::iterator it = Options.begin() + 1, ie = Options.end(); it != ie; ++it) { OS << ", " << '"' << *it << '"'; } OS << "\n"; } void MCAsmStreamer::EmitDataRegion(MCDataRegionType Kind) { if (!MAI->doesSupportDataRegionDirectives()) return; switch (Kind) { case MCDR_DataRegion: OS << "\t.data_region"; break; case MCDR_DataRegionJT8: OS << "\t.data_region jt8"; break; case MCDR_DataRegionJT16: OS << "\t.data_region jt16"; break; case MCDR_DataRegionJT32: OS << "\t.data_region jt32"; break; case MCDR_DataRegionEnd: OS << "\t.end_data_region"; break; } EmitEOL(); } void MCAsmStreamer::EmitVersionMin(MCVersionMinType Kind, unsigned Major, unsigned Minor, unsigned Update) { switch (Kind) { case MCVM_IOSVersionMin: OS << "\t.ios_version_min"; break; case MCVM_OSXVersionMin: OS << "\t.macosx_version_min"; break; } OS << " " << Major << ", " << Minor; if (Update) OS << ", " << Update; EmitEOL(); } void MCAsmStreamer::EmitThumbFunc(MCSymbol *Func) { // This needs to emit to a temporary string to get properly quoted // MCSymbols when they have spaces in them. OS << "\t.thumb_func"; // Only Mach-O hasSubsectionsViaSymbols() if (MAI->hasSubsectionsViaSymbols()) OS << '\t' << *Func; EmitEOL(); } void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) { OS << *Symbol << " = " << *Value; EmitEOL(); MCStreamer::EmitAssignment(Symbol, Value); } void MCAsmStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) { OS << ".weakref " << *Alias << ", " << *Symbol; EmitEOL(); } bool MCAsmStreamer::EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) { switch (Attribute) { case MCSA_Invalid: llvm_unreachable("Invalid symbol attribute"); case MCSA_ELF_TypeFunction: /// .type _foo, STT_FUNC # aka @function case MCSA_ELF_TypeIndFunction: /// .type _foo, STT_GNU_IFUNC case MCSA_ELF_TypeObject: /// .type _foo, STT_OBJECT # aka @object case MCSA_ELF_TypeTLS: /// .type _foo, STT_TLS # aka @tls_object case MCSA_ELF_TypeCommon: /// .type _foo, STT_COMMON # aka @common case MCSA_ELF_TypeNoType: /// .type _foo, STT_NOTYPE # aka @notype case MCSA_ELF_TypeGnuUniqueObject: /// .type _foo, @gnu_unique_object if (!MAI->hasDotTypeDotSizeDirective()) return false; // Symbol attribute not supported OS << "\t.type\t" << *Symbol << ',' << ((MAI->getCommentString()[0] != '@') ? '@' : '%'); switch (Attribute) { default: return false; case MCSA_ELF_TypeFunction: OS << "function"; break; case MCSA_ELF_TypeIndFunction: OS << "gnu_indirect_function"; break; case MCSA_ELF_TypeObject: OS << "object"; break; case MCSA_ELF_TypeTLS: OS << "tls_object"; break; case MCSA_ELF_TypeCommon: OS << "common"; break; case MCSA_ELF_TypeNoType: OS << "no_type"; break; case MCSA_ELF_TypeGnuUniqueObject: OS << "gnu_unique_object"; break; } EmitEOL(); return true; case MCSA_Global: // .globl/.global OS << MAI->getGlobalDirective(); break; case MCSA_Hidden: OS << "\t.hidden\t"; break; case MCSA_IndirectSymbol: OS << "\t.indirect_symbol\t"; break; case MCSA_Internal: OS << "\t.internal\t"; break; case MCSA_LazyReference: OS << "\t.lazy_reference\t"; break; case MCSA_Local: OS << "\t.local\t"; break; case MCSA_NoDeadStrip: OS << "\t.no_dead_strip\t"; break; case MCSA_SymbolResolver: OS << "\t.symbol_resolver\t"; break; case MCSA_PrivateExtern: OS << "\t.private_extern\t"; break; case MCSA_Protected: OS << "\t.protected\t"; break; case MCSA_Reference: OS << "\t.reference\t"; break; case MCSA_Weak: OS << "\t.weak\t"; break; case MCSA_WeakDefinition: OS << "\t.weak_definition\t"; break; // .weak_reference case MCSA_WeakReference: OS << MAI->getWeakRefDirective(); break; case MCSA_WeakDefAutoPrivate: OS << "\t.weak_def_can_be_hidden\t"; break; } OS << *Symbol; EmitEOL(); return true; } void MCAsmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) { OS << ".desc" << ' ' << *Symbol << ',' << DescValue; EmitEOL(); } void MCAsmStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) { OS << "\t.def\t " << *Symbol << ';'; EmitEOL(); } void MCAsmStreamer::EmitCOFFSymbolStorageClass (int StorageClass) { OS << "\t.scl\t" << StorageClass << ';'; EmitEOL(); } void MCAsmStreamer::EmitCOFFSymbolType (int Type) { OS << "\t.type\t" << Type << ';'; EmitEOL(); } void MCAsmStreamer::EndCOFFSymbolDef() { OS << "\t.endef"; EmitEOL(); } void MCAsmStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) { OS << "\t.secidx\t" << *Symbol; EmitEOL(); } void MCAsmStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol) { OS << "\t.secrel32\t" << *Symbol; EmitEOL(); } void MCAsmStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) { assert(MAI->hasDotTypeDotSizeDirective()); OS << "\t.size\t" << *Symbol << ", " << *Value << '\n'; } void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment) { // Common symbols do not belong to any actual section. AssignSection(Symbol, nullptr); OS << "\t.comm\t" << *Symbol << ',' << Size; if (ByteAlignment != 0) { if (MAI->getCOMMDirectiveAlignmentIsInBytes()) OS << ',' << ByteAlignment; else OS << ',' << Log2_32(ByteAlignment); } EmitEOL(); } /// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol. /// /// @param Symbol - The common symbol to emit. /// @param Size - The size of the common symbol. void MCAsmStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size, unsigned ByteAlign) { // Common symbols do not belong to any actual section. AssignSection(Symbol, nullptr); OS << "\t.lcomm\t" << *Symbol << ',' << Size; if (ByteAlign > 1) { switch (MAI->getLCOMMDirectiveAlignmentType()) { case LCOMM::NoAlignment: llvm_unreachable("alignment not supported on .lcomm!"); case LCOMM::ByteAlignment: OS << ',' << ByteAlign; break; case LCOMM::Log2Alignment: assert(isPowerOf2_32(ByteAlign) && "alignment must be a power of 2"); OS << ',' << Log2_32(ByteAlign); break; } } EmitEOL(); } void MCAsmStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment) { if (Symbol) AssignSection(Symbol, Section); // Note: a .zerofill directive does not switch sections. OS << ".zerofill "; // This is a mach-o specific directive. const MCSectionMachO *MOSection = ((const MCSectionMachO*)Section); OS << MOSection->getSegmentName() << "," << MOSection->getSectionName(); if (Symbol) { OS << ',' << *Symbol << ',' << Size; if (ByteAlignment != 0) OS << ',' << Log2_32(ByteAlignment); } EmitEOL(); } // .tbss sym, size, align // This depends that the symbol has already been mangled from the original, // e.g. _a. void MCAsmStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment) { AssignSection(Symbol, Section); assert(Symbol && "Symbol shouldn't be NULL!"); // Instead of using the Section we'll just use the shortcut. // This is a mach-o specific directive and section. OS << ".tbss " << *Symbol << ", " << Size; // Output align if we have it. We default to 1 so don't bother printing // that. if (ByteAlignment > 1) OS << ", " << Log2_32(ByteAlignment); EmitEOL(); } static inline char toOctal(int X) { return (X&7)+'0'; } static void PrintQuotedString(StringRef Data, raw_ostream &OS) { OS << '"'; for (unsigned i = 0, e = Data.size(); i != e; ++i) { unsigned char C = Data[i]; if (C == '"' || C == '\\') { OS << '\\' << (char)C; continue; } if (isprint((unsigned char)C)) { OS << (char)C; continue; } switch (C) { case '\b': OS << "\\b"; break; case '\f': OS << "\\f"; break; case '\n': OS << "\\n"; break; case '\r': OS << "\\r"; break; case '\t': OS << "\\t"; break; default: OS << '\\'; OS << toOctal(C >> 6); OS << toOctal(C >> 3); OS << toOctal(C >> 0); break; } } OS << '"'; } void MCAsmStreamer::EmitBytes(StringRef Data) { assert(getCurrentSection().first && "Cannot emit contents before setting section!"); if (Data.empty()) return; if (Data.size() == 1) { OS << MAI->getData8bitsDirective(); OS << (unsigned)(unsigned char)Data[0]; EmitEOL(); return; } // If the data ends with 0 and the target supports .asciz, use it, otherwise // use .ascii if (MAI->getAscizDirective() && Data.back() == 0) { OS << MAI->getAscizDirective(); Data = Data.substr(0, Data.size()-1); } else { OS << MAI->getAsciiDirective(); } PrintQuotedString(Data, OS); EmitEOL(); } void MCAsmStreamer::EmitIntValue(uint64_t Value, unsigned Size) { EmitValue(MCConstantExpr::Create(Value, getContext()), Size); } void MCAsmStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size, const SMLoc &Loc) { assert(Size <= 8 && "Invalid size"); assert(getCurrentSection().first && "Cannot emit contents before setting section!"); const char *Directive = nullptr; switch (Size) { default: break; case 1: Directive = MAI->getData8bitsDirective(); break; case 2: Directive = MAI->getData16bitsDirective(); break; case 4: Directive = MAI->getData32bitsDirective(); break; case 8: Directive = MAI->getData64bitsDirective(); break; } if (!Directive) { int64_t IntValue; if (!Value->EvaluateAsAbsolute(IntValue)) report_fatal_error("Don't know how to emit this value."); // We couldn't handle the requested integer size so we fallback by breaking // the request down into several, smaller, integers. Since sizes greater // than eight are invalid and size equivalent to eight should have been // handled earlier, we use four bytes as our largest piece of granularity. bool IsLittleEndian = MAI->isLittleEndian(); for (unsigned Emitted = 0; Emitted != Size;) { unsigned Remaining = Size - Emitted; // The size of our partial emission must be a power of two less than // eight. unsigned EmissionSize = PowerOf2Floor(Remaining); if (EmissionSize > 4) EmissionSize = 4; // Calculate the byte offset of our partial emission taking into account // the endianness of the target. unsigned ByteOffset = IsLittleEndian ? Emitted : (Remaining - EmissionSize); uint64_t ValueToEmit = IntValue >> (ByteOffset * 8); // We truncate our partial emission to fit within the bounds of the // emission domain. This produces nicer output and silences potential // truncation warnings when round tripping through another assembler. ValueToEmit &= ~0ULL >> (64 - EmissionSize * 8); EmitIntValue(ValueToEmit, EmissionSize); Emitted += EmissionSize; } return; } assert(Directive && "Invalid size for machine code value!"); OS << Directive << *Value; EmitEOL(); } void MCAsmStreamer::EmitULEB128Value(const MCExpr *Value) { int64_t IntValue; if (Value->EvaluateAsAbsolute(IntValue)) { EmitULEB128IntValue(IntValue); return; } assert(MAI->hasLEB128() && "Cannot print a .uleb"); OS << ".uleb128 " << *Value; EmitEOL(); } void MCAsmStreamer::EmitSLEB128Value(const MCExpr *Value) { int64_t IntValue; if (Value->EvaluateAsAbsolute(IntValue)) { EmitSLEB128IntValue(IntValue); return; } assert(MAI->hasLEB128() && "Cannot print a .sleb"); OS << ".sleb128 " << *Value; EmitEOL(); } void MCAsmStreamer::EmitGPRel64Value(const MCExpr *Value) { assert(MAI->getGPRel64Directive() != nullptr); OS << MAI->getGPRel64Directive() << *Value; EmitEOL(); } void MCAsmStreamer::EmitGPRel32Value(const MCExpr *Value) { assert(MAI->getGPRel32Directive() != nullptr); OS << MAI->getGPRel32Directive() << *Value; EmitEOL(); } /// EmitFill - Emit NumBytes bytes worth of the value specified by /// FillValue. This implements directives such as '.space'. void MCAsmStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) { if (NumBytes == 0) return; if (const char *ZeroDirective = MAI->getZeroDirective()) { OS << ZeroDirective << NumBytes; if (FillValue != 0) OS << ',' << (int)FillValue; EmitEOL(); return; } // Emit a byte at a time. MCStreamer::EmitFill(NumBytes, FillValue); } void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value, unsigned ValueSize, unsigned MaxBytesToEmit) { // Some assemblers don't support non-power of two alignments, so we always // emit alignments as a power of two if possible. if (isPowerOf2_32(ByteAlignment)) { switch (ValueSize) { default: llvm_unreachable("Invalid size for machine code value!"); case 1: OS << "\t.align\t"; break; case 2: OS << ".p2alignw "; break; case 4: OS << ".p2alignl "; break; case 8: llvm_unreachable("Unsupported alignment size!"); } if (MAI->getAlignmentIsInBytes()) OS << ByteAlignment; else OS << Log2_32(ByteAlignment); if (Value || MaxBytesToEmit) { OS << ", 0x"; OS.write_hex(truncateToSize(Value, ValueSize)); if (MaxBytesToEmit) OS << ", " << MaxBytesToEmit; } EmitEOL(); return; } // Non-power of two alignment. This is not widely supported by assemblers. // FIXME: Parameterize this based on MAI. switch (ValueSize) { default: llvm_unreachable("Invalid size for machine code value!"); case 1: OS << ".balign"; break; case 2: OS << ".balignw"; break; case 4: OS << ".balignl"; break; case 8: llvm_unreachable("Unsupported alignment size!"); } OS << ' ' << ByteAlignment; OS << ", " << truncateToSize(Value, ValueSize); if (MaxBytesToEmit) OS << ", " << MaxBytesToEmit; EmitEOL(); } void MCAsmStreamer::EmitCodeAlignment(unsigned ByteAlignment, unsigned MaxBytesToEmit) { // Emit with a text fill value. EmitValueToAlignment(ByteAlignment, MAI->getTextAlignFillValue(), 1, MaxBytesToEmit); } bool MCAsmStreamer::EmitValueToOffset(const MCExpr *Offset, unsigned char Value) { // FIXME: Verify that Offset is associated with the current section. OS << ".org " << *Offset << ", " << (unsigned) Value; EmitEOL(); return false; } void MCAsmStreamer::EmitFileDirective(StringRef Filename) { assert(MAI->hasSingleParameterDotFile()); OS << "\t.file\t"; PrintQuotedString(Filename, OS); EmitEOL(); } unsigned MCAsmStreamer::EmitDwarfFileDirective(unsigned FileNo, StringRef Directory, StringRef Filename, unsigned CUID) { assert(CUID == 0); MCDwarfLineTable &Table = getContext().getMCDwarfLineTable(CUID); unsigned NumFiles = Table.getMCDwarfFiles().size(); FileNo = Table.getFile(Directory, Filename, FileNo); if (FileNo == 0) return 0; if (NumFiles == Table.getMCDwarfFiles().size()) return FileNo; SmallString<128> FullPathName; if (!UseDwarfDirectory && !Directory.empty()) { if (sys::path::is_absolute(Filename)) Directory = ""; else { FullPathName = Directory; sys::path::append(FullPathName, Filename); Directory = ""; Filename = FullPathName; } } OS << "\t.file\t" << FileNo << ' '; if (!Directory.empty()) { PrintQuotedString(Directory, OS); OS << ' '; } PrintQuotedString(Filename, OS); EmitEOL(); return FileNo; } void MCAsmStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line, unsigned Column, unsigned Flags, unsigned Isa, unsigned Discriminator, StringRef FileName) { this->MCStreamer::EmitDwarfLocDirective(FileNo, Line, Column, Flags, Isa, Discriminator, FileName); OS << "\t.loc\t" << FileNo << " " << Line << " " << Column; if (Flags & DWARF2_FLAG_BASIC_BLOCK) OS << " basic_block"; if (Flags & DWARF2_FLAG_PROLOGUE_END) OS << " prologue_end"; if (Flags & DWARF2_FLAG_EPILOGUE_BEGIN) OS << " epilogue_begin"; unsigned OldFlags = getContext().getCurrentDwarfLoc().getFlags(); if ((Flags & DWARF2_FLAG_IS_STMT) != (OldFlags & DWARF2_FLAG_IS_STMT)) { OS << " is_stmt "; if (Flags & DWARF2_FLAG_IS_STMT) OS << "1"; else OS << "0"; } if (Isa) OS << " isa " << Isa; if (Discriminator) OS << " discriminator " << Discriminator; if (IsVerboseAsm) { OS.PadToColumn(MAI->getCommentColumn()); OS << MAI->getCommentString() << ' ' << FileName << ':' << Line << ':' << Column; } EmitEOL(); } MCSymbol *MCAsmStreamer::getDwarfLineTableSymbol(unsigned CUID) { // Always use the zeroth line table, since asm syntax only supports one line // table for now. return MCStreamer::getDwarfLineTableSymbol(0); } void MCAsmStreamer::EmitIdent(StringRef IdentString) { assert(MAI->hasIdentDirective() && ".ident directive not supported"); OS << "\t.ident\t"; PrintQuotedString(IdentString, OS); EmitEOL(); } void MCAsmStreamer::EmitCFISections(bool EH, bool Debug) { MCStreamer::EmitCFISections(EH, Debug); OS << "\t.cfi_sections "; if (EH) { OS << ".eh_frame"; if (Debug) OS << ", .debug_frame"; } else if (Debug) { OS << ".debug_frame"; } EmitEOL(); } void MCAsmStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) { OS << "\t.cfi_startproc"; if (Frame.IsSimple) OS << " simple"; EmitEOL(); } void MCAsmStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) { MCStreamer::EmitCFIEndProcImpl(Frame); OS << "\t.cfi_endproc"; EmitEOL(); } void MCAsmStreamer::EmitRegisterName(int64_t Register) { if (InstPrinter && !MAI->useDwarfRegNumForCFI()) { const MCRegisterInfo *MRI = getContext().getRegisterInfo(); unsigned LLVMRegister = MRI->getLLVMRegNum(Register, true); InstPrinter->printRegName(OS, LLVMRegister); } else { OS << Register; } } void MCAsmStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) { MCStreamer::EmitCFIDefCfa(Register, Offset); OS << "\t.cfi_def_cfa "; EmitRegisterName(Register); OS << ", " << Offset; EmitEOL(); } void MCAsmStreamer::EmitCFIDefCfaOffset(int64_t Offset) { MCStreamer::EmitCFIDefCfaOffset(Offset); OS << "\t.cfi_def_cfa_offset " << Offset; EmitEOL(); } void MCAsmStreamer::EmitCFIDefCfaRegister(int64_t Register) { MCStreamer::EmitCFIDefCfaRegister(Register); OS << "\t.cfi_def_cfa_register "; EmitRegisterName(Register); EmitEOL(); } void MCAsmStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) { this->MCStreamer::EmitCFIOffset(Register, Offset); OS << "\t.cfi_offset "; EmitRegisterName(Register); OS << ", " << Offset; EmitEOL(); } void MCAsmStreamer::EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding) { MCStreamer::EmitCFIPersonality(Sym, Encoding); OS << "\t.cfi_personality " << Encoding << ", " << *Sym; EmitEOL(); } void MCAsmStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) { MCStreamer::EmitCFILsda(Sym, Encoding); OS << "\t.cfi_lsda " << Encoding << ", " << *Sym; EmitEOL(); } void MCAsmStreamer::EmitCFIRememberState() { MCStreamer::EmitCFIRememberState(); OS << "\t.cfi_remember_state"; EmitEOL(); } void MCAsmStreamer::EmitCFIRestoreState() { MCStreamer::EmitCFIRestoreState(); OS << "\t.cfi_restore_state"; EmitEOL(); } void MCAsmStreamer::EmitCFISameValue(int64_t Register) { MCStreamer::EmitCFISameValue(Register); OS << "\t.cfi_same_value "; EmitRegisterName(Register); EmitEOL(); } void MCAsmStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) { MCStreamer::EmitCFIRelOffset(Register, Offset); OS << "\t.cfi_rel_offset "; EmitRegisterName(Register); OS << ", " << Offset; EmitEOL(); } void MCAsmStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) { MCStreamer::EmitCFIAdjustCfaOffset(Adjustment); OS << "\t.cfi_adjust_cfa_offset " << Adjustment; EmitEOL(); } void MCAsmStreamer::EmitCFISignalFrame() { MCStreamer::EmitCFISignalFrame(); OS << "\t.cfi_signal_frame"; EmitEOL(); } void MCAsmStreamer::EmitCFIUndefined(int64_t Register) { MCStreamer::EmitCFIUndefined(Register); OS << "\t.cfi_undefined " << Register; EmitEOL(); } void MCAsmStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) { MCStreamer::EmitCFIRegister(Register1, Register2); OS << "\t.cfi_register " << Register1 << ", " << Register2; EmitEOL(); } void MCAsmStreamer::EmitCFIWindowSave() { MCStreamer::EmitCFIWindowSave(); OS << "\t.cfi_window_save"; EmitEOL(); } void MCAsmStreamer::EmitWinCFIStartProc(const MCSymbol *Symbol) { MCStreamer::EmitWinCFIStartProc(Symbol); OS << ".seh_proc " << *Symbol; EmitEOL(); } void MCAsmStreamer::EmitWinCFIEndProc() { MCStreamer::EmitWinCFIEndProc(); OS << "\t.seh_endproc"; EmitEOL(); } void MCAsmStreamer::EmitWinCFIStartChained() { MCStreamer::EmitWinCFIStartChained(); OS << "\t.seh_startchained"; EmitEOL(); } void MCAsmStreamer::EmitWinCFIEndChained() { MCStreamer::EmitWinCFIEndChained(); OS << "\t.seh_endchained"; EmitEOL(); } void MCAsmStreamer::EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except) { MCStreamer::EmitWinEHHandler(Sym, Unwind, Except); OS << "\t.seh_handler " << *Sym; if (Unwind) OS << ", @unwind"; if (Except) OS << ", @except"; EmitEOL(); } static const MCSection *getWin64EHTableSection(StringRef suffix, MCContext &context) { // FIXME: This doesn't belong in MCObjectFileInfo. However, /// this duplicate code in MCWin64EH.cpp. if (suffix == "") return context.getObjectFileInfo()->getXDataSection(); return context.getCOFFSection((".xdata"+suffix).str(), COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, SectionKind::getDataRel()); } void MCAsmStreamer::EmitWinEHHandlerData() { MCStreamer::EmitWinEHHandlerData(); // Switch sections. Don't call SwitchSection directly, because that will // cause the section switch to be visible in the emitted assembly. // We only do this so the section switch that terminates the handler // data block is visible. MCWin64EHUnwindInfo *CurFrame = getCurrentW64UnwindInfo(); StringRef suffix=MCWin64EHUnwindEmitter::GetSectionSuffix(CurFrame->Function); const MCSection *xdataSect = getWin64EHTableSection(suffix, getContext()); if (xdataSect) SwitchSectionNoChange(xdataSect); OS << "\t.seh_handlerdata"; EmitEOL(); } void MCAsmStreamer::EmitWinCFIPushReg(unsigned Register) { MCStreamer::EmitWinCFIPushReg(Register); OS << "\t.seh_pushreg " << Register; EmitEOL(); } void MCAsmStreamer::EmitWinCFISetFrame(unsigned Register, unsigned Offset) { MCStreamer::EmitWinCFISetFrame(Register, Offset); OS << "\t.seh_setframe " << Register << ", " << Offset; EmitEOL(); } void MCAsmStreamer::EmitWinCFIAllocStack(unsigned Size) { MCStreamer::EmitWinCFIAllocStack(Size); OS << "\t.seh_stackalloc " << Size; EmitEOL(); } void MCAsmStreamer::EmitWinCFISaveReg(unsigned Register, unsigned Offset) { MCStreamer::EmitWinCFISaveReg(Register, Offset); OS << "\t.seh_savereg " << Register << ", " << Offset; EmitEOL(); } void MCAsmStreamer::EmitWinCFISaveXMM(unsigned Register, unsigned Offset) { MCStreamer::EmitWinCFISaveXMM(Register, Offset); OS << "\t.seh_savexmm " << Register << ", " << Offset; EmitEOL(); } void MCAsmStreamer::EmitWinCFIPushFrame(bool Code) { MCStreamer::EmitWinCFIPushFrame(Code); OS << "\t.seh_pushframe"; if (Code) OS << " @code"; EmitEOL(); } void MCAsmStreamer::EmitWinCFIEndProlog(void) { MCStreamer::EmitWinCFIEndProlog(); OS << "\t.seh_endprologue"; EmitEOL(); } void MCAsmStreamer::AddEncodingComment(const MCInst &Inst, const MCSubtargetInfo &STI) { raw_ostream &OS = GetCommentOS(); SmallString<256> Code; SmallVector<MCFixup, 4> Fixups; raw_svector_ostream VecOS(Code); Emitter->EncodeInstruction(Inst, VecOS, Fixups, STI); VecOS.flush(); // If we are showing fixups, create symbolic markers in the encoded // representation. We do this by making a per-bit map to the fixup item index, // then trying to display it as nicely as possible. SmallVector<uint8_t, 64> FixupMap; FixupMap.resize(Code.size() * 8); for (unsigned i = 0, e = Code.size() * 8; i != e; ++i) FixupMap[i] = 0; for (unsigned i = 0, e = Fixups.size(); i != e; ++i) { MCFixup &F = Fixups[i]; const MCFixupKindInfo &Info = AsmBackend->getFixupKindInfo(F.getKind()); for (unsigned j = 0; j != Info.TargetSize; ++j) { unsigned Index = F.getOffset() * 8 + Info.TargetOffset + j; assert(Index < Code.size() * 8 && "Invalid offset in fixup!"); FixupMap[Index] = 1 + i; } } // FIXME: Note the fixup comments for Thumb2 are completely bogus since the // high order halfword of a 32-bit Thumb2 instruction is emitted first. OS << "encoding: ["; for (unsigned i = 0, e = Code.size(); i != e; ++i) { if (i) OS << ','; // See if all bits are the same map entry. uint8_t MapEntry = FixupMap[i * 8 + 0]; for (unsigned j = 1; j != 8; ++j) { if (FixupMap[i * 8 + j] == MapEntry) continue; MapEntry = uint8_t(~0U); break; } if (MapEntry != uint8_t(~0U)) { if (MapEntry == 0) { OS << format("0x%02x", uint8_t(Code[i])); } else { if (Code[i]) { // FIXME: Some of the 8 bits require fix up. OS << format("0x%02x", uint8_t(Code[i])) << '\'' << char('A' + MapEntry - 1) << '\''; } else OS << char('A' + MapEntry - 1); } } else { // Otherwise, write out in binary. OS << "0b"; for (unsigned j = 8; j--;) { unsigned Bit = (Code[i] >> j) & 1; unsigned FixupBit; if (MAI->isLittleEndian()) FixupBit = i * 8 + j; else FixupBit = i * 8 + (7-j); if (uint8_t MapEntry = FixupMap[FixupBit]) { assert(Bit == 0 && "Encoder wrote into fixed up bit!"); OS << char('A' + MapEntry - 1); } else OS << Bit; } } } OS << "]\n"; for (unsigned i = 0, e = Fixups.size(); i != e; ++i) { MCFixup &F = Fixups[i]; const MCFixupKindInfo &Info = AsmBackend->getFixupKindInfo(F.getKind()); OS << " fixup " << char('A' + i) << " - " << "offset: " << F.getOffset() << ", value: " << *F.getValue() << ", kind: " << Info.Name << "\n"; } } void MCAsmStreamer::EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) { assert(getCurrentSection().first && "Cannot emit contents before setting section!"); // Show the encoding in a comment if we have a code emitter. if (Emitter) AddEncodingComment(Inst, STI); // Show the MCInst if enabled. if (ShowInst) { Inst.dump_pretty(GetCommentOS(), MAI, InstPrinter.get(), "\n "); GetCommentOS() << "\n"; } // If we have an AsmPrinter, use that to print, otherwise print the MCInst. if (InstPrinter) InstPrinter->printInst(&Inst, OS, ""); else Inst.print(OS, MAI); EmitEOL(); } void MCAsmStreamer::EmitBundleAlignMode(unsigned AlignPow2) { OS << "\t.bundle_align_mode " << AlignPow2; EmitEOL(); } void MCAsmStreamer::EmitBundleLock(bool AlignToEnd) { OS << "\t.bundle_lock"; if (AlignToEnd) OS << " align_to_end"; EmitEOL(); } void MCAsmStreamer::EmitBundleUnlock() { OS << "\t.bundle_unlock"; EmitEOL(); } /// EmitRawText - If this file is backed by an assembly streamer, this dumps /// the specified string in the output .s file. This capability is /// indicated by the hasRawTextSupport() predicate. void MCAsmStreamer::EmitRawTextImpl(StringRef String) { if (!String.empty() && String.back() == '\n') String = String.substr(0, String.size()-1); OS << String; EmitEOL(); } void MCAsmStreamer::FinishImpl() { // If we are generating dwarf for assembly source files dump out the sections. if (getContext().getGenDwarfForAssembly()) MCGenDwarfInfo::Emit(this); // Emit the label for the line table, if requested - since the rest of the // line table will be defined by .loc/.file directives, and not emitted // directly, the label is the only work required here. auto &Tables = getContext().getMCDwarfLineTables(); if (!Tables.empty()) { assert(Tables.size() == 1 && "asm output only supports one line table"); if (auto *Label = Tables.begin()->second.getLabel()) { SwitchSection(getContext().getObjectFileInfo()->getDwarfLineSection()); EmitLabel(Label); } } } MCStreamer *llvm::createAsmStreamer(MCContext &Context, formatted_raw_ostream &OS, bool isVerboseAsm, bool useDwarfDirectory, MCInstPrinter *IP, MCCodeEmitter *CE, MCAsmBackend *MAB, bool ShowInst) { return new MCAsmStreamer(Context, OS, isVerboseAsm, useDwarfDirectory, IP, CE, MAB, ShowInst); }