| //===- lib/MC/MCObjectStreamer.cpp - Object File MCStreamer Interface -----===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/MC/MCObjectStreamer.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/MC/MCAsmBackend.h" |
| #include "llvm/MC/MCAssembler.h" |
| #include "llvm/MC/MCCodeEmitter.h" |
| #include "llvm/MC/MCCodeView.h" |
| #include "llvm/MC/MCContext.h" |
| #include "llvm/MC/MCDwarf.h" |
| #include "llvm/MC/MCExpr.h" |
| #include "llvm/MC/MCObjectWriter.h" |
| #include "llvm/MC/MCSection.h" |
| #include "llvm/MC/MCSymbol.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/SourceMgr.h" |
| using namespace llvm; |
| |
| MCObjectStreamer::MCObjectStreamer(MCContext &Context, |
| std::unique_ptr<MCAsmBackend> TAB, |
| std::unique_ptr<MCObjectWriter> OW, |
| std::unique_ptr<MCCodeEmitter> Emitter) |
| : MCStreamer(Context), |
| Assembler(llvm::make_unique<MCAssembler>( |
| Context, std::move(TAB), std::move(Emitter), std::move(OW))), |
| EmitEHFrame(true), EmitDebugFrame(false) {} |
| |
| MCObjectStreamer::~MCObjectStreamer() {} |
| |
| // AssemblerPtr is used for evaluation of expressions and causes |
| // difference between asm and object outputs. Return nullptr to in |
| // inline asm mode to limit divergence to assembly inputs. |
| MCAssembler *MCObjectStreamer::getAssemblerPtr() { |
| if (getUseAssemblerInfoForParsing()) |
| return Assembler.get(); |
| return nullptr; |
| } |
| |
| void MCObjectStreamer::flushPendingLabels(MCFragment *F, uint64_t FOffset) { |
| if (PendingLabels.empty()) |
| return; |
| if (!F) { |
| F = new MCDataFragment(); |
| MCSection *CurSection = getCurrentSectionOnly(); |
| CurSection->getFragmentList().insert(CurInsertionPoint, F); |
| F->setParent(CurSection); |
| } |
| for (MCSymbol *Sym : PendingLabels) { |
| Sym->setFragment(F); |
| Sym->setOffset(FOffset); |
| } |
| PendingLabels.clear(); |
| } |
| |
| // When fixup's offset is a forward declared label, e.g.: |
| // |
| // .reloc 1f, R_MIPS_JALR, foo |
| // 1: nop |
| // |
| // postpone adding it to Fixups vector until the label is defined and its offset |
| // is known. |
| void MCObjectStreamer::resolvePendingFixups() { |
| for (PendingMCFixup &PendingFixup : PendingFixups) { |
| if (!PendingFixup.Sym || PendingFixup.Sym->isUndefined ()) { |
| getContext().reportError(PendingFixup.Fixup.getLoc(), |
| "unresolved relocation offset"); |
| continue; |
| } |
| flushPendingLabels(PendingFixup.DF, PendingFixup.DF->getContents().size()); |
| PendingFixup.Fixup.setOffset(PendingFixup.Sym->getOffset()); |
| PendingFixup.DF->getFixups().push_back(PendingFixup.Fixup); |
| } |
| PendingFixups.clear(); |
| } |
| |
| // As a compile-time optimization, avoid allocating and evaluating an MCExpr |
| // tree for (Hi - Lo) when Hi and Lo are offsets into the same fragment. |
| static Optional<uint64_t> |
| absoluteSymbolDiff(MCAssembler &Asm, const MCSymbol *Hi, const MCSymbol *Lo) { |
| assert(Hi && Lo); |
| if (Asm.getBackendPtr()->requiresDiffExpressionRelocations()) |
| return None; |
| |
| if (!Hi->getFragment() || Hi->getFragment() != Lo->getFragment() || |
| Hi->isVariable() || Lo->isVariable()) |
| return None; |
| |
| return Hi->getOffset() - Lo->getOffset(); |
| } |
| |
| void MCObjectStreamer::emitAbsoluteSymbolDiff(const MCSymbol *Hi, |
| const MCSymbol *Lo, |
| unsigned Size) { |
| if (Optional<uint64_t> Diff = absoluteSymbolDiff(getAssembler(), Hi, Lo)) { |
| EmitIntValue(*Diff, Size); |
| return; |
| } |
| MCStreamer::emitAbsoluteSymbolDiff(Hi, Lo, Size); |
| } |
| |
| void MCObjectStreamer::emitAbsoluteSymbolDiffAsULEB128(const MCSymbol *Hi, |
| const MCSymbol *Lo) { |
| if (Optional<uint64_t> Diff = absoluteSymbolDiff(getAssembler(), Hi, Lo)) { |
| EmitULEB128IntValue(*Diff); |
| return; |
| } |
| MCStreamer::emitAbsoluteSymbolDiffAsULEB128(Hi, Lo); |
| } |
| |
| void MCObjectStreamer::reset() { |
| if (Assembler) |
| Assembler->reset(); |
| CurInsertionPoint = MCSection::iterator(); |
| EmitEHFrame = true; |
| EmitDebugFrame = false; |
| PendingLabels.clear(); |
| MCStreamer::reset(); |
| } |
| |
| void MCObjectStreamer::EmitFrames(MCAsmBackend *MAB) { |
| if (!getNumFrameInfos()) |
| return; |
| |
| if (EmitEHFrame) |
| MCDwarfFrameEmitter::Emit(*this, MAB, true); |
| |
| if (EmitDebugFrame) |
| MCDwarfFrameEmitter::Emit(*this, MAB, false); |
| } |
| |
| MCFragment *MCObjectStreamer::getCurrentFragment() const { |
| assert(getCurrentSectionOnly() && "No current section!"); |
| |
| if (CurInsertionPoint != getCurrentSectionOnly()->getFragmentList().begin()) |
| return &*std::prev(CurInsertionPoint); |
| |
| return nullptr; |
| } |
| |
| static bool CanReuseDataFragment(const MCDataFragment &F, |
| const MCAssembler &Assembler, |
| const MCSubtargetInfo *STI) { |
| if (!F.hasInstructions()) |
| return true; |
| // When bundling is enabled, we don't want to add data to a fragment that |
| // already has instructions (see MCELFStreamer::EmitInstToData for details) |
| if (Assembler.isBundlingEnabled()) |
| return Assembler.getRelaxAll(); |
| // If the subtarget is changed mid fragment we start a new fragment to record |
| // the new STI. |
| return !STI || F.getSubtargetInfo() == STI; |
| } |
| |
| MCDataFragment * |
| MCObjectStreamer::getOrCreateDataFragment(const MCSubtargetInfo *STI) { |
| MCDataFragment *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment()); |
| if (!F || !CanReuseDataFragment(*F, *Assembler, STI)) { |
| F = new MCDataFragment(); |
| insert(F); |
| } |
| return F; |
| } |
| |
| MCPaddingFragment *MCObjectStreamer::getOrCreatePaddingFragment() { |
| MCPaddingFragment *F = |
| dyn_cast_or_null<MCPaddingFragment>(getCurrentFragment()); |
| if (!F) { |
| F = new MCPaddingFragment(); |
| insert(F); |
| } |
| return F; |
| } |
| |
| void MCObjectStreamer::visitUsedSymbol(const MCSymbol &Sym) { |
| Assembler->registerSymbol(Sym); |
| } |
| |
| void MCObjectStreamer::EmitCFISections(bool EH, bool Debug) { |
| MCStreamer::EmitCFISections(EH, Debug); |
| EmitEHFrame = EH; |
| EmitDebugFrame = Debug; |
| } |
| |
| void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size, |
| SMLoc Loc) { |
| MCStreamer::EmitValueImpl(Value, Size, Loc); |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| MCDwarfLineEntry::Make(this, getCurrentSectionOnly()); |
| |
| // Avoid fixups when possible. |
| int64_t AbsValue; |
| if (Value->evaluateAsAbsolute(AbsValue, getAssemblerPtr())) { |
| if (!isUIntN(8 * Size, AbsValue) && !isIntN(8 * Size, AbsValue)) { |
| getContext().reportError( |
| Loc, "value evaluated as " + Twine(AbsValue) + " is out of range."); |
| return; |
| } |
| EmitIntValue(AbsValue, Size); |
| return; |
| } |
| DF->getFixups().push_back( |
| MCFixup::create(DF->getContents().size(), Value, |
| MCFixup::getKindForSize(Size, false), Loc)); |
| DF->getContents().resize(DF->getContents().size() + Size, 0); |
| } |
| |
| MCSymbol *MCObjectStreamer::EmitCFILabel() { |
| MCSymbol *Label = getContext().createTempSymbol("cfi", true); |
| EmitLabel(Label); |
| return Label; |
| } |
| |
| void MCObjectStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) { |
| // We need to create a local symbol to avoid relocations. |
| Frame.Begin = getContext().createTempSymbol(); |
| EmitLabel(Frame.Begin); |
| } |
| |
| void MCObjectStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) { |
| Frame.End = getContext().createTempSymbol(); |
| EmitLabel(Frame.End); |
| } |
| |
| void MCObjectStreamer::EmitLabel(MCSymbol *Symbol, SMLoc Loc) { |
| MCStreamer::EmitLabel(Symbol, Loc); |
| |
| getAssembler().registerSymbol(*Symbol); |
| |
| // If there is a current fragment, mark the symbol as pointing into it. |
| // Otherwise queue the label and set its fragment pointer when we emit the |
| // next fragment. |
| auto *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment()); |
| if (F && !(getAssembler().isBundlingEnabled() && |
| getAssembler().getRelaxAll())) { |
| Symbol->setFragment(F); |
| Symbol->setOffset(F->getContents().size()); |
| } else { |
| PendingLabels.push_back(Symbol); |
| } |
| } |
| |
| void MCObjectStreamer::EmitLabel(MCSymbol *Symbol, SMLoc Loc, MCFragment *F) { |
| MCStreamer::EmitLabel(Symbol, Loc); |
| getAssembler().registerSymbol(*Symbol); |
| auto *DF = dyn_cast_or_null<MCDataFragment>(F); |
| if (DF) |
| Symbol->setFragment(F); |
| else |
| PendingLabels.push_back(Symbol); |
| } |
| |
| void MCObjectStreamer::EmitULEB128Value(const MCExpr *Value) { |
| int64_t IntValue; |
| if (Value->evaluateAsAbsolute(IntValue, getAssemblerPtr())) { |
| EmitULEB128IntValue(IntValue); |
| return; |
| } |
| insert(new MCLEBFragment(*Value, false)); |
| } |
| |
| void MCObjectStreamer::EmitSLEB128Value(const MCExpr *Value) { |
| int64_t IntValue; |
| if (Value->evaluateAsAbsolute(IntValue, getAssemblerPtr())) { |
| EmitSLEB128IntValue(IntValue); |
| return; |
| } |
| insert(new MCLEBFragment(*Value, true)); |
| } |
| |
| void MCObjectStreamer::EmitWeakReference(MCSymbol *Alias, |
| const MCSymbol *Symbol) { |
| report_fatal_error("This file format doesn't support weak aliases."); |
| } |
| |
| void MCObjectStreamer::ChangeSection(MCSection *Section, |
| const MCExpr *Subsection) { |
| changeSectionImpl(Section, Subsection); |
| } |
| |
| bool MCObjectStreamer::changeSectionImpl(MCSection *Section, |
| const MCExpr *Subsection) { |
| assert(Section && "Cannot switch to a null section!"); |
| flushPendingLabels(nullptr); |
| getContext().clearDwarfLocSeen(); |
| |
| bool Created = getAssembler().registerSection(*Section); |
| |
| int64_t IntSubsection = 0; |
| if (Subsection && |
| !Subsection->evaluateAsAbsolute(IntSubsection, getAssemblerPtr())) |
| report_fatal_error("Cannot evaluate subsection number"); |
| if (IntSubsection < 0 || IntSubsection > 8192) |
| report_fatal_error("Subsection number out of range"); |
| CurInsertionPoint = |
| Section->getSubsectionInsertionPoint(unsigned(IntSubsection)); |
| return Created; |
| } |
| |
| void MCObjectStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) { |
| getAssembler().registerSymbol(*Symbol); |
| MCStreamer::EmitAssignment(Symbol, Value); |
| } |
| |
| bool MCObjectStreamer::mayHaveInstructions(MCSection &Sec) const { |
| return Sec.hasInstructions(); |
| } |
| |
| void MCObjectStreamer::EmitInstruction(const MCInst &Inst, |
| const MCSubtargetInfo &STI) { |
| getAssembler().getBackend().handleCodePaddingInstructionBegin(Inst); |
| EmitInstructionImpl(Inst, STI); |
| getAssembler().getBackend().handleCodePaddingInstructionEnd(Inst); |
| } |
| |
| void MCObjectStreamer::EmitInstructionImpl(const MCInst &Inst, |
| const MCSubtargetInfo &STI) { |
| MCStreamer::EmitInstruction(Inst, STI); |
| |
| MCSection *Sec = getCurrentSectionOnly(); |
| Sec->setHasInstructions(true); |
| |
| // Now that a machine instruction has been assembled into this section, make |
| // a line entry for any .loc directive that has been seen. |
| MCDwarfLineEntry::Make(this, getCurrentSectionOnly()); |
| |
| // If this instruction doesn't need relaxation, just emit it as data. |
| MCAssembler &Assembler = getAssembler(); |
| if (!Assembler.getBackend().mayNeedRelaxation(Inst, STI)) { |
| EmitInstToData(Inst, STI); |
| return; |
| } |
| |
| // Otherwise, relax and emit it as data if either: |
| // - The RelaxAll flag was passed |
| // - Bundling is enabled and this instruction is inside a bundle-locked |
| // group. We want to emit all such instructions into the same data |
| // fragment. |
| if (Assembler.getRelaxAll() || |
| (Assembler.isBundlingEnabled() && Sec->isBundleLocked())) { |
| MCInst Relaxed; |
| getAssembler().getBackend().relaxInstruction(Inst, STI, Relaxed); |
| while (getAssembler().getBackend().mayNeedRelaxation(Relaxed, STI)) |
| getAssembler().getBackend().relaxInstruction(Relaxed, STI, Relaxed); |
| EmitInstToData(Relaxed, STI); |
| return; |
| } |
| |
| // Otherwise emit to a separate fragment. |
| EmitInstToFragment(Inst, STI); |
| } |
| |
| void MCObjectStreamer::EmitInstToFragment(const MCInst &Inst, |
| const MCSubtargetInfo &STI) { |
| if (getAssembler().getRelaxAll() && getAssembler().isBundlingEnabled()) |
| llvm_unreachable("All instructions should have already been relaxed"); |
| |
| // Always create a new, separate fragment here, because its size can change |
| // during relaxation. |
| MCRelaxableFragment *IF = new MCRelaxableFragment(Inst, STI); |
| insert(IF); |
| |
| SmallString<128> Code; |
| raw_svector_ostream VecOS(Code); |
| getAssembler().getEmitter().encodeInstruction(Inst, VecOS, IF->getFixups(), |
| STI); |
| IF->getContents().append(Code.begin(), Code.end()); |
| } |
| |
| #ifndef NDEBUG |
| static const char *const BundlingNotImplementedMsg = |
| "Aligned bundling is not implemented for this object format"; |
| #endif |
| |
| void MCObjectStreamer::EmitBundleAlignMode(unsigned AlignPow2) { |
| llvm_unreachable(BundlingNotImplementedMsg); |
| } |
| |
| void MCObjectStreamer::EmitBundleLock(bool AlignToEnd) { |
| llvm_unreachable(BundlingNotImplementedMsg); |
| } |
| |
| void MCObjectStreamer::EmitBundleUnlock() { |
| llvm_unreachable(BundlingNotImplementedMsg); |
| } |
| |
| void MCObjectStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line, |
| unsigned Column, unsigned Flags, |
| unsigned Isa, |
| unsigned Discriminator, |
| StringRef FileName) { |
| // In case we see two .loc directives in a row, make sure the |
| // first one gets a line entry. |
| MCDwarfLineEntry::Make(this, getCurrentSectionOnly()); |
| |
| this->MCStreamer::EmitDwarfLocDirective(FileNo, Line, Column, Flags, |
| Isa, Discriminator, FileName); |
| } |
| |
| static const MCExpr *buildSymbolDiff(MCObjectStreamer &OS, const MCSymbol *A, |
| const MCSymbol *B) { |
| MCContext &Context = OS.getContext(); |
| 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; |
| } |
| |
| static void emitDwarfSetLineAddr(MCObjectStreamer &OS, |
| MCDwarfLineTableParams Params, |
| int64_t LineDelta, const MCSymbol *Label, |
| int PointerSize) { |
| // emit the sequence to set the address |
| OS.EmitIntValue(dwarf::DW_LNS_extended_op, 1); |
| OS.EmitULEB128IntValue(PointerSize + 1); |
| OS.EmitIntValue(dwarf::DW_LNE_set_address, 1); |
| OS.EmitSymbolValue(Label, PointerSize); |
| |
| // emit the sequence for the LineDelta (from 1) and a zero address delta. |
| MCDwarfLineAddr::Emit(&OS, Params, LineDelta, 0); |
| } |
| |
| void MCObjectStreamer::EmitDwarfAdvanceLineAddr(int64_t LineDelta, |
| const MCSymbol *LastLabel, |
| const MCSymbol *Label, |
| unsigned PointerSize) { |
| if (!LastLabel) { |
| emitDwarfSetLineAddr(*this, Assembler->getDWARFLinetableParams(), LineDelta, |
| Label, PointerSize); |
| return; |
| } |
| const MCExpr *AddrDelta = buildSymbolDiff(*this, Label, LastLabel); |
| int64_t Res; |
| if (AddrDelta->evaluateAsAbsolute(Res, getAssemblerPtr())) { |
| MCDwarfLineAddr::Emit(this, Assembler->getDWARFLinetableParams(), LineDelta, |
| Res); |
| return; |
| } |
| insert(new MCDwarfLineAddrFragment(LineDelta, *AddrDelta)); |
| } |
| |
| void MCObjectStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel, |
| const MCSymbol *Label) { |
| const MCExpr *AddrDelta = buildSymbolDiff(*this, Label, LastLabel); |
| int64_t Res; |
| if (AddrDelta->evaluateAsAbsolute(Res, getAssemblerPtr())) { |
| MCDwarfFrameEmitter::EmitAdvanceLoc(*this, Res); |
| return; |
| } |
| insert(new MCDwarfCallFrameFragment(*AddrDelta)); |
| } |
| |
| void MCObjectStreamer::EmitCVLocDirective(unsigned FunctionId, unsigned FileNo, |
| unsigned Line, unsigned Column, |
| bool PrologueEnd, bool IsStmt, |
| StringRef FileName, SMLoc Loc) { |
| // Validate the directive. |
| if (!checkCVLocSection(FunctionId, FileNo, Loc)) |
| return; |
| |
| // Emit a label at the current position and record it in the CodeViewContext. |
| MCSymbol *LineSym = getContext().createTempSymbol(); |
| EmitLabel(LineSym); |
| getContext().getCVContext().recordCVLoc(getContext(), LineSym, FunctionId, |
| FileNo, Line, Column, PrologueEnd, |
| IsStmt); |
| } |
| |
| void MCObjectStreamer::EmitCVLinetableDirective(unsigned FunctionId, |
| const MCSymbol *Begin, |
| const MCSymbol *End) { |
| getContext().getCVContext().emitLineTableForFunction(*this, FunctionId, Begin, |
| End); |
| this->MCStreamer::EmitCVLinetableDirective(FunctionId, Begin, End); |
| } |
| |
| void MCObjectStreamer::EmitCVInlineLinetableDirective( |
| unsigned PrimaryFunctionId, unsigned SourceFileId, unsigned SourceLineNum, |
| const MCSymbol *FnStartSym, const MCSymbol *FnEndSym) { |
| getContext().getCVContext().emitInlineLineTableForFunction( |
| *this, PrimaryFunctionId, SourceFileId, SourceLineNum, FnStartSym, |
| FnEndSym); |
| this->MCStreamer::EmitCVInlineLinetableDirective( |
| PrimaryFunctionId, SourceFileId, SourceLineNum, FnStartSym, FnEndSym); |
| } |
| |
| void MCObjectStreamer::EmitCVDefRangeDirective( |
| ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges, |
| StringRef FixedSizePortion) { |
| MCFragment *Frag = |
| getContext().getCVContext().emitDefRange(*this, Ranges, FixedSizePortion); |
| // Attach labels that were pending before we created the defrange fragment to |
| // the beginning of the new fragment. |
| flushPendingLabels(Frag, 0); |
| this->MCStreamer::EmitCVDefRangeDirective(Ranges, FixedSizePortion); |
| } |
| |
| void MCObjectStreamer::EmitCVStringTableDirective() { |
| getContext().getCVContext().emitStringTable(*this); |
| } |
| void MCObjectStreamer::EmitCVFileChecksumsDirective() { |
| getContext().getCVContext().emitFileChecksums(*this); |
| } |
| |
| void MCObjectStreamer::EmitCVFileChecksumOffsetDirective(unsigned FileNo) { |
| getContext().getCVContext().emitFileChecksumOffset(*this, FileNo); |
| } |
| |
| void MCObjectStreamer::EmitBytes(StringRef Data) { |
| MCDwarfLineEntry::Make(this, getCurrentSectionOnly()); |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| DF->getContents().append(Data.begin(), Data.end()); |
| |
| // EmitBytes might not cover all possible ways we emit data (or could be used |
| // to emit executable code in some cases), but is the best method we have |
| // right now for checking this. |
| MCSection *Sec = getCurrentSectionOnly(); |
| Sec->setHasData(true); |
| } |
| |
| void MCObjectStreamer::EmitValueToAlignment(unsigned ByteAlignment, |
| int64_t Value, |
| unsigned ValueSize, |
| unsigned MaxBytesToEmit) { |
| if (MaxBytesToEmit == 0) |
| MaxBytesToEmit = ByteAlignment; |
| insert(new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit)); |
| |
| // Update the maximum alignment on the current section if necessary. |
| MCSection *CurSec = getCurrentSectionOnly(); |
| if (ByteAlignment > CurSec->getAlignment()) |
| CurSec->setAlignment(ByteAlignment); |
| } |
| |
| void MCObjectStreamer::EmitCodeAlignment(unsigned ByteAlignment, |
| unsigned MaxBytesToEmit) { |
| EmitValueToAlignment(ByteAlignment, 0, 1, MaxBytesToEmit); |
| cast<MCAlignFragment>(getCurrentFragment())->setEmitNops(true); |
| } |
| |
| void MCObjectStreamer::emitValueToOffset(const MCExpr *Offset, |
| unsigned char Value, |
| SMLoc Loc) { |
| insert(new MCOrgFragment(*Offset, Value, Loc)); |
| } |
| |
| void MCObjectStreamer::EmitCodePaddingBasicBlockStart( |
| const MCCodePaddingContext &Context) { |
| getAssembler().getBackend().handleCodePaddingBasicBlockStart(this, Context); |
| } |
| |
| void MCObjectStreamer::EmitCodePaddingBasicBlockEnd( |
| const MCCodePaddingContext &Context) { |
| getAssembler().getBackend().handleCodePaddingBasicBlockEnd(Context); |
| } |
| |
| // Associate DTPRel32 fixup with data and resize data area |
| void MCObjectStreamer::EmitDTPRel32Value(const MCExpr *Value) { |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| DF->getFixups().push_back(MCFixup::create(DF->getContents().size(), |
| Value, FK_DTPRel_4)); |
| DF->getContents().resize(DF->getContents().size() + 4, 0); |
| } |
| |
| // Associate DTPRel64 fixup with data and resize data area |
| void MCObjectStreamer::EmitDTPRel64Value(const MCExpr *Value) { |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| DF->getFixups().push_back(MCFixup::create(DF->getContents().size(), |
| Value, FK_DTPRel_8)); |
| DF->getContents().resize(DF->getContents().size() + 8, 0); |
| } |
| |
| // Associate TPRel32 fixup with data and resize data area |
| void MCObjectStreamer::EmitTPRel32Value(const MCExpr *Value) { |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| DF->getFixups().push_back(MCFixup::create(DF->getContents().size(), |
| Value, FK_TPRel_4)); |
| DF->getContents().resize(DF->getContents().size() + 4, 0); |
| } |
| |
| // Associate TPRel64 fixup with data and resize data area |
| void MCObjectStreamer::EmitTPRel64Value(const MCExpr *Value) { |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| DF->getFixups().push_back(MCFixup::create(DF->getContents().size(), |
| Value, FK_TPRel_8)); |
| DF->getContents().resize(DF->getContents().size() + 8, 0); |
| } |
| |
| // Associate GPRel32 fixup with data and resize data area |
| void MCObjectStreamer::EmitGPRel32Value(const MCExpr *Value) { |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| DF->getFixups().push_back( |
| MCFixup::create(DF->getContents().size(), Value, FK_GPRel_4)); |
| DF->getContents().resize(DF->getContents().size() + 4, 0); |
| } |
| |
| // Associate GPRel64 fixup with data and resize data area |
| void MCObjectStreamer::EmitGPRel64Value(const MCExpr *Value) { |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| DF->getFixups().push_back( |
| MCFixup::create(DF->getContents().size(), Value, FK_GPRel_4)); |
| DF->getContents().resize(DF->getContents().size() + 8, 0); |
| } |
| |
| bool MCObjectStreamer::EmitRelocDirective(const MCExpr &Offset, StringRef Name, |
| const MCExpr *Expr, SMLoc Loc, |
| const MCSubtargetInfo &STI) { |
| Optional<MCFixupKind> MaybeKind = Assembler->getBackend().getFixupKind(Name); |
| if (!MaybeKind.hasValue()) |
| return true; |
| |
| MCFixupKind Kind = *MaybeKind; |
| |
| if (Expr == nullptr) |
| Expr = |
| MCSymbolRefExpr::create(getContext().createTempSymbol(), getContext()); |
| |
| MCDataFragment *DF = getOrCreateDataFragment(&STI); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| int64_t OffsetValue; |
| if (Offset.evaluateAsAbsolute(OffsetValue)) { |
| if (OffsetValue < 0) |
| llvm_unreachable(".reloc offset is negative"); |
| DF->getFixups().push_back(MCFixup::create(OffsetValue, Expr, Kind, Loc)); |
| return false; |
| } |
| |
| if (Offset.getKind() != llvm::MCExpr::SymbolRef) |
| llvm_unreachable(".reloc offset is not absolute nor a label"); |
| |
| const MCSymbolRefExpr &SRE = cast<MCSymbolRefExpr>(Offset); |
| if (SRE.getSymbol().isDefined()) { |
| DF->getFixups().push_back(MCFixup::create(SRE.getSymbol().getOffset(), |
| Expr, Kind, Loc)); |
| return false; |
| } |
| |
| PendingFixups.emplace_back(&SRE.getSymbol(), DF, |
| MCFixup::create(-1, Expr, Kind, Loc)); |
| return false; |
| } |
| |
| void MCObjectStreamer::emitFill(const MCExpr &NumBytes, uint64_t FillValue, |
| SMLoc Loc) { |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| assert(getCurrentSectionOnly() && "need a section"); |
| insert(new MCFillFragment(FillValue, 1, NumBytes, Loc)); |
| } |
| |
| void MCObjectStreamer::emitFill(const MCExpr &NumValues, int64_t Size, |
| int64_t Expr, SMLoc Loc) { |
| int64_t IntNumValues; |
| // Do additional checking now if we can resolve the value. |
| if (NumValues.evaluateAsAbsolute(IntNumValues, getAssemblerPtr())) { |
| if (IntNumValues < 0) { |
| getContext().getSourceManager()->PrintMessage( |
| Loc, SourceMgr::DK_Warning, |
| "'.fill' directive with negative repeat count has no effect"); |
| return; |
| } |
| // Emit now if we can for better errors. |
| int64_t NonZeroSize = Size > 4 ? 4 : Size; |
| Expr &= ~0ULL >> (64 - NonZeroSize * 8); |
| for (uint64_t i = 0, e = IntNumValues; i != e; ++i) { |
| EmitIntValue(Expr, NonZeroSize); |
| if (NonZeroSize < Size) |
| EmitIntValue(0, Size - NonZeroSize); |
| } |
| return; |
| } |
| |
| // Otherwise emit as fragment. |
| MCDataFragment *DF = getOrCreateDataFragment(); |
| flushPendingLabels(DF, DF->getContents().size()); |
| |
| assert(getCurrentSectionOnly() && "need a section"); |
| insert(new MCFillFragment(Expr, Size, NumValues, Loc)); |
| } |
| |
| void MCObjectStreamer::EmitFileDirective(StringRef Filename) { |
| getAssembler().addFileName(Filename); |
| } |
| |
| void MCObjectStreamer::EmitAddrsig() { |
| getAssembler().getWriter().emitAddrsigSection(); |
| } |
| |
| void MCObjectStreamer::EmitAddrsigSym(const MCSymbol *Sym) { |
| getAssembler().registerSymbol(*Sym); |
| getAssembler().getWriter().addAddrsigSymbol(Sym); |
| } |
| |
| void MCObjectStreamer::FinishImpl() { |
| getContext().RemapDebugPaths(); |
| |
| // If we are generating dwarf for assembly source files dump out the sections. |
| if (getContext().getGenDwarfForAssembly()) |
| MCGenDwarfInfo::Emit(this); |
| |
| // Dump out the dwarf file & directory tables and line tables. |
| MCDwarfLineTable::Emit(this, getAssembler().getDWARFLinetableParams()); |
| |
| flushPendingLabels(); |
| resolvePendingFixups(); |
| getAssembler().Finish(); |
| } |