//===- lib/MC/MCStreamer.cpp - Streaming Machine Code 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/Twine.h" #include "llvm/MC/MCAsmInfo.h" #include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCObjectWriter.h" #include "llvm/MC/MCSymbol.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/LEB128.h" #include "llvm/Support/raw_ostream.h" #include <cstdlib> using namespace llvm; MCStreamer::MCStreamer(StreamerKind Kind, MCContext &Ctx) : Kind(Kind), Context(Ctx), EmitEHFrame(true), EmitDebugFrame(false), CurrentW64UnwindInfo(0), LastSymbol(0), AutoInitSections(false) { SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>()); } MCStreamer::~MCStreamer() { for (unsigned i = 0; i < getNumW64UnwindInfos(); ++i) delete W64UnwindInfos[i]; } void MCStreamer::reset() { for (unsigned i = 0; i < getNumW64UnwindInfos(); ++i) delete W64UnwindInfos[i]; W64UnwindInfos.clear(); EmitEHFrame = true; EmitDebugFrame = false; CurrentW64UnwindInfo = 0; LastSymbol = 0; SectionStack.clear(); SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>()); } const MCExpr *MCStreamer::BuildSymbolDiff(MCContext &Context, const MCSymbol *A, const MCSymbol *B) { MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None; const MCExpr *ARef = MCSymbolRefExpr::Create(A, Variant, Context); const MCExpr *BRef = MCSymbolRefExpr::Create(B, Variant, Context); const MCExpr *AddrDelta = MCBinaryExpr::Create(MCBinaryExpr::Sub, ARef, BRef, Context); return AddrDelta; } const MCExpr *MCStreamer::ForceExpAbs(const MCExpr* Expr) { if (Context.getAsmInfo()->hasAggressiveSymbolFolding() || isa<MCSymbolRefExpr>(Expr)) return Expr; MCSymbol *ABS = Context.CreateTempSymbol(); EmitAssignment(ABS, Expr); return MCSymbolRefExpr::Create(ABS, Context); } raw_ostream &MCStreamer::GetCommentOS() { // By default, discard comments. return nulls(); } void MCStreamer::EmitDwarfSetLineAddr(int64_t LineDelta, const MCSymbol *Label, int PointerSize) { // emit the sequence to set the address EmitIntValue(dwarf::DW_LNS_extended_op, 1); EmitULEB128IntValue(PointerSize + 1); EmitIntValue(dwarf::DW_LNE_set_address, 1); EmitSymbolValue(Label, PointerSize); // emit the sequence for the LineDelta (from 1) and a zero address delta. MCDwarfLineAddr::Emit(this, LineDelta, 0); } /// EmitIntValue - Special case of EmitValue that avoids the client having to /// pass in a MCExpr for constant integers. void MCStreamer::EmitIntValue(uint64_t Value, unsigned Size) { assert(Size <= 8 && "Invalid size"); assert((isUIntN(8 * Size, Value) || isIntN(8 * Size, Value)) && "Invalid size"); char buf[8]; const bool isLittleEndian = Context.getAsmInfo()->isLittleEndian(); for (unsigned i = 0; i != Size; ++i) { unsigned index = isLittleEndian ? i : (Size - i - 1); buf[i] = uint8_t(Value >> (index * 8)); } EmitBytes(StringRef(buf, Size)); } /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the /// client having to pass in a MCExpr for constant integers. void MCStreamer::EmitULEB128IntValue(uint64_t Value, unsigned Padding) { SmallString<128> Tmp; raw_svector_ostream OSE(Tmp); encodeULEB128(Value, OSE, Padding); EmitBytes(OSE.str()); } /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the /// client having to pass in a MCExpr for constant integers. void MCStreamer::EmitSLEB128IntValue(int64_t Value) { SmallString<128> Tmp; raw_svector_ostream OSE(Tmp); encodeSLEB128(Value, OSE); EmitBytes(OSE.str()); } void MCStreamer::EmitAbsValue(const MCExpr *Value, unsigned Size) { const MCExpr *ABS = ForceExpAbs(Value); EmitValue(ABS, Size); } void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size) { EmitValueImpl(Value, Size); } void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size) { EmitValueImpl(MCSymbolRefExpr::Create(Sym, getContext()), Size); } void MCStreamer::EmitGPRel64Value(const MCExpr *Value) { report_fatal_error("unsupported directive in streamer"); } void MCStreamer::EmitGPRel32Value(const MCExpr *Value) { report_fatal_error("unsupported directive in streamer"); } /// EmitFill - Emit NumBytes bytes worth of the value specified by /// FillValue. This implements directives such as '.space'. void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) { const MCExpr *E = MCConstantExpr::Create(FillValue, getContext()); for (uint64_t i = 0, e = NumBytes; i != e; ++i) EmitValue(E, 1); } /// The implementation in this class just redirects to EmitFill. void MCStreamer::EmitZeros(uint64_t NumBytes) { EmitFill(NumBytes, 0); } bool MCStreamer::EmitDwarfFileDirective(unsigned FileNo, StringRef Directory, StringRef Filename, unsigned CUID) { return getContext().GetDwarfFile(Directory, Filename, FileNo, CUID) == 0; } void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line, unsigned Column, unsigned Flags, unsigned Isa, unsigned Discriminator, StringRef FileName) { getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa, Discriminator); } MCDwarfFrameInfo *MCStreamer::getCurrentFrameInfo() { if (FrameInfos.empty()) return 0; return &FrameInfos.back(); } void MCStreamer::EnsureValidFrame() { MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); if (!CurFrame || CurFrame->End) report_fatal_error("No open frame"); } void MCStreamer::EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol) { } void MCStreamer::EmitLabel(MCSymbol *Symbol) { assert(!Symbol->isVariable() && "Cannot emit a variable symbol!"); assert(getCurrentSection().first && "Cannot emit before setting section!"); Symbol->setSection(*getCurrentSection().first); LastSymbol = Symbol; } void MCStreamer::EmitDebugLabel(MCSymbol *Symbol) { assert(!Symbol->isVariable() && "Cannot emit a variable symbol!"); assert(getCurrentSection().first && "Cannot emit before setting section!"); Symbol->setSection(*getCurrentSection().first); LastSymbol = Symbol; } void MCStreamer::EmitCompactUnwindEncoding(uint32_t CompactUnwindEncoding) { EnsureValidFrame(); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->CompactUnwindEncoding = CompactUnwindEncoding; } void MCStreamer::EmitCFISections(bool EH, bool Debug) { assert(EH || Debug); EmitEHFrame = EH; EmitDebugFrame = Debug; } void MCStreamer::EmitCFIStartProc() { MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); if (CurFrame && !CurFrame->End) report_fatal_error("Starting a frame before finishing the previous one!"); MCDwarfFrameInfo Frame; EmitCFIStartProcImpl(Frame); FrameInfos.push_back(Frame); } void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) { } void MCStreamer::RecordProcStart(MCDwarfFrameInfo &Frame) { Frame.Function = LastSymbol; // If the function is externally visible, we need to create a local // symbol to avoid relocations. StringRef Prefix = getContext().getAsmInfo()->getPrivateGlobalPrefix(); if (LastSymbol && LastSymbol->getName().startswith(Prefix)) { Frame.Begin = LastSymbol; } else { Frame.Begin = getContext().CreateTempSymbol(); EmitLabel(Frame.Begin); } } void MCStreamer::EmitCFIEndProc() { EnsureValidFrame(); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); EmitCFIEndProcImpl(*CurFrame); } void MCStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) { } void MCStreamer::RecordProcEnd(MCDwarfFrameInfo &Frame) { Frame.End = getContext().CreateTempSymbol(); EmitLabel(Frame.End); } MCSymbol *MCStreamer::EmitCFICommon() { EnsureValidFrame(); MCSymbol *Label = getContext().CreateTempSymbol(); EmitLabel(Label); return Label; } void MCStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createDefCfa(Label, Register, Offset); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createDefCfaOffset(Label, Offset); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createAdjustCfaOffset(Label, Adjustment); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIDefCfaRegister(int64_t Register) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createDefCfaRegister(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createOffset(Label, Register, Offset); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createRelOffset(Label, Register, Offset); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding) { EnsureValidFrame(); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Personality = Sym; CurFrame->PersonalityEncoding = Encoding; } void MCStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) { EnsureValidFrame(); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Lsda = Sym; CurFrame->LsdaEncoding = Encoding; } void MCStreamer::EmitCFIRememberState() { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createRememberState(Label); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRestoreState() { // FIXME: Error if there is no matching cfi_remember_state. MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createRestoreState(Label); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFISameValue(int64_t Register) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createSameValue(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRestore(int64_t Register) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createRestore(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIEscape(StringRef Values) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createEscape(Label, Values); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFISignalFrame() { EnsureValidFrame(); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->IsSignalFrame = true; } void MCStreamer::EmitCFIUndefined(int64_t Register) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createUndefined(Label, Register); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) { MCSymbol *Label = EmitCFICommon(); MCCFIInstruction Instruction = MCCFIInstruction::createRegister(Label, Register1, Register2); MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); CurFrame->Instructions.push_back(Instruction); } void MCStreamer::setCurrentW64UnwindInfo(MCWin64EHUnwindInfo *Frame) { W64UnwindInfos.push_back(Frame); CurrentW64UnwindInfo = W64UnwindInfos.back(); } void MCStreamer::EnsureValidW64UnwindInfo() { MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (!CurFrame || CurFrame->End) report_fatal_error("No open Win64 EH frame function!"); } void MCStreamer::EmitWin64EHStartProc(const MCSymbol *Symbol) { MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (CurFrame && !CurFrame->End) report_fatal_error("Starting a function before ending the previous one!"); MCWin64EHUnwindInfo *Frame = new MCWin64EHUnwindInfo; Frame->Begin = getContext().CreateTempSymbol(); Frame->Function = Symbol; EmitLabel(Frame->Begin); setCurrentW64UnwindInfo(Frame); } void MCStreamer::EmitWin64EHEndProc() { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (CurFrame->ChainedParent) report_fatal_error("Not all chained regions terminated!"); CurFrame->End = getContext().CreateTempSymbol(); EmitLabel(CurFrame->End); } void MCStreamer::EmitWin64EHStartChained() { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *Frame = new MCWin64EHUnwindInfo; MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; Frame->Begin = getContext().CreateTempSymbol(); Frame->Function = CurFrame->Function; Frame->ChainedParent = CurFrame; EmitLabel(Frame->Begin); setCurrentW64UnwindInfo(Frame); } void MCStreamer::EmitWin64EHEndChained() { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (!CurFrame->ChainedParent) report_fatal_error("End of a chained region outside a chained region!"); CurFrame->End = getContext().CreateTempSymbol(); EmitLabel(CurFrame->End); CurrentW64UnwindInfo = CurFrame->ChainedParent; } void MCStreamer::EmitWin64EHHandler(const MCSymbol *Sym, bool Unwind, bool Except) { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (CurFrame->ChainedParent) report_fatal_error("Chained unwind areas can't have handlers!"); CurFrame->ExceptionHandler = Sym; if (!Except && !Unwind) report_fatal_error("Don't know what kind of handler this is!"); if (Unwind) CurFrame->HandlesUnwind = true; if (Except) CurFrame->HandlesExceptions = true; } void MCStreamer::EmitWin64EHHandlerData() { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (CurFrame->ChainedParent) report_fatal_error("Chained unwind areas can't have handlers!"); } void MCStreamer::EmitWin64EHPushReg(unsigned Register) { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; MCSymbol *Label = getContext().CreateTempSymbol(); MCWin64EHInstruction Inst(Win64EH::UOP_PushNonVol, Label, Register); EmitLabel(Label); CurFrame->Instructions.push_back(Inst); } void MCStreamer::EmitWin64EHSetFrame(unsigned Register, unsigned Offset) { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (CurFrame->LastFrameInst >= 0) report_fatal_error("Frame register and offset already specified!"); if (Offset & 0x0F) report_fatal_error("Misaligned frame pointer offset!"); MCWin64EHInstruction Inst(Win64EH::UOP_SetFPReg, 0, Register, Offset); CurFrame->LastFrameInst = CurFrame->Instructions.size(); CurFrame->Instructions.push_back(Inst); } void MCStreamer::EmitWin64EHAllocStack(unsigned Size) { EnsureValidW64UnwindInfo(); if (Size & 7) report_fatal_error("Misaligned stack allocation!"); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; MCSymbol *Label = getContext().CreateTempSymbol(); MCWin64EHInstruction Inst(Label, Size); EmitLabel(Label); CurFrame->Instructions.push_back(Inst); } void MCStreamer::EmitWin64EHSaveReg(unsigned Register, unsigned Offset) { EnsureValidW64UnwindInfo(); if (Offset & 7) report_fatal_error("Misaligned saved register offset!"); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; MCSymbol *Label = getContext().CreateTempSymbol(); MCWin64EHInstruction Inst( Offset > 512*1024-8 ? Win64EH::UOP_SaveNonVolBig : Win64EH::UOP_SaveNonVol, Label, Register, Offset); EmitLabel(Label); CurFrame->Instructions.push_back(Inst); } void MCStreamer::EmitWin64EHSaveXMM(unsigned Register, unsigned Offset) { EnsureValidW64UnwindInfo(); if (Offset & 0x0F) report_fatal_error("Misaligned saved vector register offset!"); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; MCSymbol *Label = getContext().CreateTempSymbol(); MCWin64EHInstruction Inst( Offset > 512*1024-16 ? Win64EH::UOP_SaveXMM128Big : Win64EH::UOP_SaveXMM128, Label, Register, Offset); EmitLabel(Label); CurFrame->Instructions.push_back(Inst); } void MCStreamer::EmitWin64EHPushFrame(bool Code) { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; if (CurFrame->Instructions.size() > 0) report_fatal_error("If present, PushMachFrame must be the first UOP"); MCSymbol *Label = getContext().CreateTempSymbol(); MCWin64EHInstruction Inst(Win64EH::UOP_PushMachFrame, Label, Code); EmitLabel(Label); CurFrame->Instructions.push_back(Inst); } void MCStreamer::EmitWin64EHEndProlog() { EnsureValidW64UnwindInfo(); MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo; CurFrame->PrologEnd = getContext().CreateTempSymbol(); EmitLabel(CurFrame->PrologEnd); } void MCStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol) { llvm_unreachable("This file format doesn't support this directive"); } void MCStreamer::EmitFnStart() { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitFnEnd() { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitCantUnwind() { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitHandlerData() { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitPersonality(const MCSymbol *Personality) { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset) { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitPad(int64_t Offset) { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitRegSave(const SmallVectorImpl<unsigned> &RegList, bool) { errs() << "Not implemented yet\n"; abort(); } void MCStreamer::EmitTCEntry(const MCSymbol &S) { llvm_unreachable("Unsupported method"); } /// 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 MCStreamer::EmitRawText(StringRef String) { errs() << "EmitRawText called on an MCStreamer that doesn't support it, " " something must not be fully mc'ized\n"; abort(); } void MCStreamer::EmitRawText(const Twine &T) { SmallString<128> Str; T.toVector(Str); EmitRawText(Str.str()); } void MCStreamer::EmitFrames(bool usingCFI) { if (!getNumFrameInfos()) return; if (EmitEHFrame) MCDwarfFrameEmitter::Emit(*this, usingCFI, true); if (EmitDebugFrame) MCDwarfFrameEmitter::Emit(*this, usingCFI, false); } void MCStreamer::EmitW64Tables() { if (!getNumW64UnwindInfos()) return; MCWin64EHUnwindEmitter::Emit(*this); } void MCStreamer::Finish() { if (!FrameInfos.empty() && !FrameInfos.back().End) report_fatal_error("Unfinished frame!"); FinishImpl(); } MCSymbolData &MCStreamer::getOrCreateSymbolData(MCSymbol *Symbol) { report_fatal_error("Not supported!"); return *(static_cast<MCSymbolData*>(0)); }