Coverage Report

Created: 2017-10-03 07:32

/Users/buildslave/jenkins/sharedspace/clang-stage2-coverage-R@2/llvm/include/llvm/MC/MCStreamer.h
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//===- MCStreamer.h - High-level Streaming Machine Code Output --*- C++ -*-===//
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//
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//                     The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file declares the MCStreamer class.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_MC_MCSTREAMER_H
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#define LLVM_MC_MCSTREAMER_H
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#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/MC/MCDirectives.h"
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#include "llvm/MC/MCDwarf.h"
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#include "llvm/MC/MCLinkerOptimizationHint.h"
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#include "llvm/MC/MCSymbol.h"
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#include "llvm/MC/MCWinEH.h"
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#include "llvm/Support/SMLoc.h"
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#include "llvm/Support/TargetParser.h"
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#include <cassert>
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#include <cstdint>
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#include <memory>
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#include <string>
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#include <utility>
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#include <vector>
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namespace llvm {
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class AssemblerConstantPools;
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class formatted_raw_ostream;
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class MCAsmBackend;
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class MCCodeEmitter;
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class MCContext;
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class MCExpr;
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class MCInst;
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class MCInstPrinter;
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class MCSection;
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class MCStreamer;
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class MCSymbolRefExpr;
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class MCSubtargetInfo;
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class raw_ostream;
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class Twine;
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using MCSectionSubPair = std::pair<MCSection *, const MCExpr *>;
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/// Target specific streamer interface. This is used so that targets can
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/// implement support for target specific assembly directives.
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///
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/// If target foo wants to use this, it should implement 3 classes:
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/// * FooTargetStreamer : public MCTargetStreamer
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/// * FooTargetAsmStreamer : public FooTargetStreamer
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/// * FooTargetELFStreamer : public FooTargetStreamer
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///
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/// FooTargetStreamer should have a pure virtual method for each directive. For
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/// example, for a ".bar symbol_name" directive, it should have
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/// virtual emitBar(const MCSymbol &Symbol) = 0;
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///
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/// The FooTargetAsmStreamer and FooTargetELFStreamer classes implement the
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/// method. The assembly streamer just prints ".bar symbol_name". The object
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/// streamer does whatever is needed to implement .bar in the object file.
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///
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/// In the assembly printer and parser the target streamer can be used by
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/// calling getTargetStreamer and casting it to FooTargetStreamer:
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///
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/// MCTargetStreamer &TS = OutStreamer.getTargetStreamer();
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/// FooTargetStreamer &ATS = static_cast<FooTargetStreamer &>(TS);
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///
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/// The base classes FooTargetAsmStreamer and FooTargetELFStreamer should
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/// *never* be treated differently. Callers should always talk to a
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/// FooTargetStreamer.
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class MCTargetStreamer {
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protected:
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  MCStreamer &Streamer;
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public:
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  MCTargetStreamer(MCStreamer &S);
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  virtual ~MCTargetStreamer();
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87
10.4k
  MCStreamer &getStreamer() { return Streamer; }
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  // Allow a target to add behavior to the EmitLabel of MCStreamer.
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  virtual void emitLabel(MCSymbol *Symbol);
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  // Allow a target to add behavior to the emitAssignment of MCStreamer.
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  virtual void emitAssignment(MCSymbol *Symbol, const MCExpr *Value);
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  virtual void prettyPrintAsm(MCInstPrinter &InstPrinter, raw_ostream &OS,
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                              const MCInst &Inst, const MCSubtargetInfo &STI);
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  virtual void finish();
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};
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// FIXME: declared here because it is used from
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// lib/CodeGen/AsmPrinter/ARMException.cpp.
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class ARMTargetStreamer : public MCTargetStreamer {
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public:
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  ARMTargetStreamer(MCStreamer &S);
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  ~ARMTargetStreamer() override;
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  virtual void emitFnStart();
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  virtual void emitFnEnd();
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  virtual void emitCantUnwind();
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  virtual void emitPersonality(const MCSymbol *Personality);
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  virtual void emitPersonalityIndex(unsigned Index);
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  virtual void emitHandlerData();
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  virtual void emitSetFP(unsigned FpReg, unsigned SpReg,
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                         int64_t Offset = 0);
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  virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
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  virtual void emitPad(int64_t Offset);
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  virtual void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
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                           bool isVector);
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  virtual void emitUnwindRaw(int64_t StackOffset,
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                             const SmallVectorImpl<uint8_t> &Opcodes);
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  virtual void switchVendor(StringRef Vendor);
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  virtual void emitAttribute(unsigned Attribute, unsigned Value);
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  virtual void emitTextAttribute(unsigned Attribute, StringRef String);
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  virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
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                                    StringRef StringValue = "");
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  virtual void emitFPU(unsigned FPU);
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  virtual void emitArch(ARM::ArchKind Arch);
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  virtual void emitArchExtension(unsigned ArchExt);
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  virtual void emitObjectArch(ARM::ArchKind Arch);
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  void emitTargetAttributes(const MCSubtargetInfo &STI);
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  virtual void finishAttributeSection();
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  virtual void emitInst(uint32_t Inst, char Suffix = '\0');
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  virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
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  virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value);
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  void finish() override;
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  /// Reset any state between object emissions, i.e. the equivalent of
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  /// MCStreamer's reset method.
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  virtual void reset();
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  /// Callback used to implement the ldr= pseudo.
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  /// Add a new entry to the constant pool for the current section and return an
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  /// MCExpr that can be used to refer to the constant pool location.
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  const MCExpr *addConstantPoolEntry(const MCExpr *, SMLoc Loc);
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  /// Callback used to implemnt the .ltorg directive.
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  /// Emit contents of constant pool for the current section.
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  void emitCurrentConstantPool();
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private:
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  std::unique_ptr<AssemblerConstantPools> ConstantPools;
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};
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/// \brief Streaming machine code generation interface.
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///
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/// This interface is intended to provide a programatic interface that is very
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/// similar to the level that an assembler .s file provides.  It has callbacks
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/// to emit bytes, handle directives, etc.  The implementation of this interface
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/// retains state to know what the current section is etc.
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///
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/// There are multiple implementations of this interface: one for writing out
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/// a .s file, and implementations that write out .o files of various formats.
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///
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class MCStreamer {
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  MCContext &Context;
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  std::unique_ptr<MCTargetStreamer> TargetStreamer;
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  std::vector<MCDwarfFrameInfo> DwarfFrameInfos;
173
  MCDwarfFrameInfo *getCurrentDwarfFrameInfo();
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  void EnsureValidDwarfFrame();
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  MCSymbol *EmitCFILabel();
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  MCSymbol *EmitCFICommon();
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  std::vector<WinEH::FrameInfo *> WinFrameInfos;
180
  WinEH::FrameInfo *CurrentWinFrameInfo;
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  void EnsureValidWinFrameInfo();
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  /// \brief Tracks an index to represent the order a symbol was emitted in.
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  /// Zero means we did not emit that symbol.
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  DenseMap<const MCSymbol *, unsigned> SymbolOrdering;
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  /// \brief This is stack of current and previous section values saved by
188
  /// PushSection.
189
  SmallVector<std::pair<MCSectionSubPair, MCSectionSubPair>, 4> SectionStack;
190
191
  /// The next unique ID to use when creating a WinCFI-related section (.pdata
192
  /// or .xdata). This ID ensures that we have a one-to-one mapping from
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  /// code section to unwind info section, which MSVC's incremental linker
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  /// requires.
195
  unsigned NextWinCFIID = 0;
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protected:
198
  MCStreamer(MCContext &Ctx);
199
200
  virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
201
  virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
202
203
392
  WinEH::FrameInfo *getCurrentWinFrameInfo() {
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392
    return CurrentWinFrameInfo;
205
392
  }
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  virtual void EmitWindowsUnwindTables();
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209
  virtual void EmitRawTextImpl(StringRef String);
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public:
212
  MCStreamer(const MCStreamer &) = delete;
213
  MCStreamer &operator=(const MCStreamer &) = delete;
214
  virtual ~MCStreamer();
215
216
  void visitUsedExpr(const MCExpr &Expr);
217
  virtual void visitUsedSymbol(const MCSymbol &Sym);
218
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14.3k
  void setTargetStreamer(MCTargetStreamer *TS) {
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14.3k
    TargetStreamer.reset(TS);
221
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  }
222
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  /// State management
224
  ///
225
  virtual void reset();
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64.1M
  MCContext &getContext() const { return Context; }
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10.2M
  MCTargetStreamer *getTargetStreamer() {
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10.2M
    return TargetStreamer.get();
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10.2M
  }
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23.0k
  unsigned getNumFrameInfos() { return DwarfFrameInfos.size(); }
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7.81k
  ArrayRef<MCDwarfFrameInfo> getDwarfFrameInfos() const {
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7.81k
    return DwarfFrameInfos;
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7.81k
  }
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  bool hasUnfinishedDwarfFrameInfo();
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  unsigned getNumWinFrameInfos() { return WinFrameInfos.size(); }
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  ArrayRef<WinEH::FrameInfo *> getWinFrameInfos() const {
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    return WinFrameInfos;
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  }
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  void generateCompactUnwindEncodings(MCAsmBackend *MAB);
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  /// \name Assembly File Formatting.
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  /// @{
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  /// \brief Return true if this streamer supports verbose assembly and if it is
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  /// enabled.
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45.0k
  virtual bool isVerboseAsm() const { return false; }
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  /// \brief Return true if this asm streamer supports emitting unformatted text
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  /// to the .s file with EmitRawText.
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216k
  virtual bool hasRawTextSupport() const { return false; }
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  /// \brief Is the integrated assembler required for this streamer to function
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  /// correctly?
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1.70k
  virtual bool isIntegratedAssemblerRequired() const { return false; }
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  /// \brief Add a textual comment.
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  ///
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  /// Typically for comments that can be emitted to the generated .s
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  /// file if applicable as a QoI issue to make the output of the compiler
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  /// more readable.  This only affects the MCAsmStreamer, and only when
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  /// verbose assembly output is enabled.
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  ///
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  /// If the comment includes embedded \n's, they will each get the comment
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  /// prefix as appropriate.  The added comment should not end with a \n.
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  /// By default, each comment is terminated with an end of line, i.e. the
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  /// EOL param is set to true by default. If one prefers not to end the 
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  /// comment with a new line then the EOL param should be passed 
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  /// with a false value.
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181k
  virtual void AddComment(const Twine &T, bool EOL = true) {}
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  /// \brief Return a raw_ostream that comments can be written to. Unlike
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  /// AddComment, you are required to terminate comments with \n if you use this
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  /// method.
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  virtual raw_ostream &GetCommentOS();
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  /// \brief Print T and prefix it with the comment string (normally #) and
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  /// optionally a tab. This prints the comment immediately, not at the end of
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  /// the current line. It is basically a safe version of EmitRawText: since it
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  /// only prints comments, the object streamer ignores it instead of asserting.
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  virtual void emitRawComment(const Twine &T, bool TabPrefix = true);
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  /// \brief Add explicit comment T. T is required to be a valid
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  /// comment in the output and does not need to be escaped.
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  virtual void addExplicitComment(const Twine &T);
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  /// \brief Emit added explicit comments.
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  virtual void emitExplicitComments();
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  /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
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1.36M
  virtual void AddBlankLine() {}
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  /// @}
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  /// \name Symbol & Section Management
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  /// @{
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  /// \brief Return the current section that the streamer is emitting code to.
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103M
  MCSectionSubPair getCurrentSection() const {
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103M
    if (!SectionStack.empty())
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103M
      return SectionStack.back().first;
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18.4E
    return MCSectionSubPair();
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103M
  }
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103M
  MCSection *getCurrentSectionOnly() const { return getCurrentSection().first; }
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  /// \brief Return the previous section that the streamer is emitting code to.
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13.0k
  MCSectionSubPair getPreviousSection() const {
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13.0k
    if (!SectionStack.empty())
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13.0k
      return SectionStack.back().second;
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0
    return MCSectionSubPair();
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13.0k
  }
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  /// \brief Returns an index to represent the order a symbol was emitted in.
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  /// (zero if we did not emit that symbol)
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14
  unsigned GetSymbolOrder(const MCSymbol *Sym) const {
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14
    return SymbolOrdering.lookup(Sym);
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14
  }
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  /// \brief Update streamer for a new active section.
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  ///
326
  /// This is called by PopSection and SwitchSection, if the current
327
  /// section changes.
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  virtual void ChangeSection(MCSection *, const MCExpr *);
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  /// \brief Save the current and previous section on the section stack.
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1.29k
  void PushSection() {
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1.29k
    SectionStack.push_back(
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1.29k
        std::make_pair(getCurrentSection(), getPreviousSection()));
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1.29k
  }
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  /// \brief Restore the current and previous section from the section stack.
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  /// Calls ChangeSection as needed.
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  ///
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  /// Returns false if the stack was empty.
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1.29k
  bool PopSection() {
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1.29k
    if (SectionStack.size() <= 1)
342
0
      return false;
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1.29k
    auto I = SectionStack.end();
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1.29k
    --I;
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1.29k
    MCSectionSubPair OldSection = I->first;
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1.29k
    --I;
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1.29k
    MCSectionSubPair NewSection = I->first;
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1.29k
349
1.29k
    if (OldSection != NewSection)
350
1.07k
      ChangeSection(NewSection.first, NewSection.second);
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1.29k
    SectionStack.pop_back();
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1.29k
    return true;
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1.29k
  }
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355
4
  bool SubSection(const MCExpr *Subsection) {
356
4
    if (SectionStack.empty())
357
0
      return false;
358
4
359
4
    SwitchSection(SectionStack.back().first.first, Subsection);
360
4
    return true;
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4
  }
362
363
  /// Set the current section where code is being emitted to \p Section.  This
364
  /// is required to update CurSection.
365
  ///
366
  /// This corresponds to assembler directives like .section, .text, etc.
367
  virtual void SwitchSection(MCSection *Section,
368
                             const MCExpr *Subsection = nullptr);
369
370
  /// \brief Set the current section where code is being emitted to \p Section.
371
  /// This is required to update CurSection. This version does not call
372
  /// ChangeSection.
373
  void SwitchSectionNoChange(MCSection *Section,
374
328
                             const MCExpr *Subsection = nullptr) {
375
328
    assert(Section && "Cannot switch to a null section!");
376
328
    MCSectionSubPair curSection = SectionStack.back().first;
377
328
    SectionStack.back().second = curSection;
378
328
    if (MCSectionSubPair(Section, Subsection) != curSection)
379
328
      SectionStack.back().first = MCSectionSubPair(Section, Subsection);
380
328
  }
381
382
  /// \brief Create the default sections and set the initial one.
383
  virtual void InitSections(bool NoExecStack);
384
385
  MCSymbol *endSection(MCSection *Section);
386
387
  /// \brief Sets the symbol's section.
388
  ///
389
  /// Each emitted symbol will be tracked in the ordering table,
390
  /// so we can sort on them later.
391
  void AssignFragment(MCSymbol *Symbol, MCFragment *Fragment);
392
393
  /// \brief Emit a label for \p Symbol into the current section.
394
  ///
395
  /// This corresponds to an assembler statement such as:
396
  ///   foo:
397
  ///
398
  /// \param Symbol - The symbol to emit. A given symbol should only be
399
  /// emitted as a label once, and symbols emitted as a label should never be
400
  /// used in an assignment.
401
  // FIXME: These emission are non-const because we mutate the symbol to
402
  // add the section we're emitting it to later.
403
  virtual void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc());
404
405
  virtual void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol);
406
407
  /// \brief Note in the output the specified \p Flag.
408
  virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
409
410
  /// \brief Emit the given list \p Options of strings as linker
411
  /// options into the output.
412
0
  virtual void EmitLinkerOptions(ArrayRef<std::string> Kind) {}
413
414
  /// \brief Note in the output the specified region \p Kind.
415
132
  virtual void EmitDataRegion(MCDataRegionType Kind) {}
416
417
  /// \brief Specify the MachO minimum deployment target version.
418
  virtual void EmitVersionMin(MCVersionMinType, unsigned Major, unsigned Minor,
419
67
                              unsigned Update) {}
420
421
  /// \brief Note in the output that the specified \p Func is a Thumb mode
422
  /// function (ARM target only).
423
  virtual void EmitThumbFunc(MCSymbol *Func);
424
425
  /// \brief Emit an assignment of \p Value to \p Symbol.
426
  ///
427
  /// This corresponds to an assembler statement such as:
428
  ///  symbol = value
429
  ///
430
  /// The assignment generates no code, but has the side effect of binding the
431
  /// value in the current context. For the assembly streamer, this prints the
432
  /// binding into the .s file.
433
  ///
434
  /// \param Symbol - The symbol being assigned to.
435
  /// \param Value - The value for the symbol.
436
  virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
437
438
  /// \brief Emit an weak reference from \p Alias to \p Symbol.
439
  ///
440
  /// This corresponds to an assembler statement such as:
441
  ///  .weakref alias, symbol
442
  ///
443
  /// \param Alias - The alias that is being created.
444
  /// \param Symbol - The symbol being aliased.
445
  virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
446
447
  /// \brief Add the given \p Attribute to \p Symbol.
448
  virtual bool EmitSymbolAttribute(MCSymbol *Symbol,
449
                                   MCSymbolAttr Attribute) = 0;
450
451
  /// \brief Set the \p DescValue for the \p Symbol.
452
  ///
453
  /// \param Symbol - The symbol to have its n_desc field set.
454
  /// \param DescValue - The value to set into the n_desc field.
455
  virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
456
457
  /// \brief Start emitting COFF symbol definition
458
  ///
459
  /// \param Symbol - The symbol to have its External & Type fields set.
460
  virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
461
462
  /// \brief Emit the storage class of the symbol.
463
  ///
464
  /// \param StorageClass - The storage class the symbol should have.
465
  virtual void EmitCOFFSymbolStorageClass(int StorageClass);
466
467
  /// \brief Emit the type of the symbol.
468
  ///
469
  /// \param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
470
  virtual void EmitCOFFSymbolType(int Type);
471
472
  /// \brief Marks the end of the symbol definition.
473
  virtual void EndCOFFSymbolDef();
474
475
  virtual void EmitCOFFSafeSEH(MCSymbol const *Symbol);
476
477
  /// \brief Emits a COFF section index.
478
  ///
479
  /// \param Symbol - Symbol the section number relocation should point to.
480
  virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
481
482
  /// \brief Emits a COFF section relative relocation.
483
  ///
484
  /// \param Symbol - Symbol the section relative relocation should point to.
485
  virtual void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset);
486
487
  /// \brief Emit an ELF .size directive.
488
  ///
489
  /// This corresponds to an assembler statement such as:
490
  ///  .size symbol, expression
491
  virtual void emitELFSize(MCSymbol *Symbol, const MCExpr *Value);
492
493
  /// \brief Emit an ELF .symver directive.
494
  ///
495
  /// This corresponds to an assembler statement such as:
496
  ///  .symver _start, foo@@SOME_VERSION
497
  /// \param Alias - The versioned alias (i.e. "foo@@SOME_VERSION")
498
  /// \param Aliasee - The aliased symbol (i.e. "_start")
499
  virtual void emitELFSymverDirective(MCSymbol *Alias, const MCSymbol *Aliasee);
500
501
  /// \brief Emit a Linker Optimization Hint (LOH) directive.
502
  /// \param Args - Arguments of the LOH.
503
0
  virtual void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {}
504
505
  /// \brief Emit a common symbol.
506
  ///
507
  /// \param Symbol - The common symbol to emit.
508
  /// \param Size - The size of the common symbol.
509
  /// \param ByteAlignment - The alignment of the symbol if
510
  /// non-zero. This must be a power of 2.
511
  virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
512
                                unsigned ByteAlignment) = 0;
513
514
  /// \brief Emit a local common (.lcomm) symbol.
515
  ///
516
  /// \param Symbol - The common symbol to emit.
517
  /// \param Size - The size of the common symbol.
518
  /// \param ByteAlignment - The alignment of the common symbol in bytes.
519
  virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
520
                                     unsigned ByteAlignment);
521
522
  /// \brief Emit the zerofill section and an optional symbol.
523
  ///
524
  /// \param Section - The zerofill section to create and or to put the symbol
525
  /// \param Symbol - The zerofill symbol to emit, if non-NULL.
526
  /// \param Size - The size of the zerofill symbol.
527
  /// \param ByteAlignment - The alignment of the zerofill symbol if
528
  /// non-zero. This must be a power of 2 on some targets.
529
  virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
530
                            uint64_t Size = 0, unsigned ByteAlignment = 0) = 0;
531
532
  /// \brief Emit a thread local bss (.tbss) symbol.
533
  ///
534
  /// \param Section - The thread local common section.
535
  /// \param Symbol - The thread local common symbol to emit.
536
  /// \param Size - The size of the symbol.
537
  /// \param ByteAlignment - The alignment of the thread local common symbol
538
  /// if non-zero.  This must be a power of 2 on some targets.
539
  virtual void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
540
                              uint64_t Size, unsigned ByteAlignment = 0);
541
542
  /// @}
543
  /// \name Generating Data
544
  /// @{
545
546
  /// \brief Emit the bytes in \p Data into the output.
547
  ///
548
  /// This is used to implement assembler directives such as .byte, .ascii,
549
  /// etc.
550
  virtual void EmitBytes(StringRef Data);
551
552
  /// Functionally identical to EmitBytes. When emitting textual assembly, this
553
  /// method uses .byte directives instead of .ascii or .asciz for readability.
554
  virtual void EmitBinaryData(StringRef Data);
555
556
  /// \brief Emit the expression \p Value into the output as a native
557
  /// integer of the given \p Size bytes.
558
  ///
559
  /// This is used to implement assembler directives such as .word, .quad,
560
  /// etc.
561
  ///
562
  /// \param Value - The value to emit.
563
  /// \param Size - The size of the integer (in bytes) to emit. This must
564
  /// match a native machine width.
565
  /// \param Loc - The location of the expression for error reporting.
566
  virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
567
                             SMLoc Loc = SMLoc());
568
569
  void EmitValue(const MCExpr *Value, unsigned Size, SMLoc Loc = SMLoc());
570
571
  /// \brief Special case of EmitValue that avoids the client having
572
  /// to pass in a MCExpr for constant integers.
573
  virtual void EmitIntValue(uint64_t Value, unsigned Size);
574
575
  virtual void EmitULEB128Value(const MCExpr *Value);
576
577
  virtual void EmitSLEB128Value(const MCExpr *Value);
578
579
  /// \brief Special case of EmitULEB128Value that avoids the client having to
580
  /// pass in a MCExpr for constant integers.
581
  void EmitULEB128IntValue(uint64_t Value);
582
583
  /// \brief Like EmitULEB128Value but pads the output to specific number of
584
  /// bytes.
585
  void EmitPaddedULEB128IntValue(uint64_t Value, unsigned PadTo);
586
587
  /// \brief Special case of EmitSLEB128Value that avoids the client having to
588
  /// pass in a MCExpr for constant integers.
589
  void EmitSLEB128IntValue(int64_t Value);
590
591
  /// \brief Special case of EmitValue that avoids the client having to pass in
592
  /// a MCExpr for MCSymbols.
593
  void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
594
                       bool IsSectionRelative = false);
595
596
  /// \brief Emit the expression \p Value into the output as a dtprel
597
  /// (64-bit DTP relative) value.
598
  ///
599
  /// This is used to implement assembler directives such as .dtpreldword on
600
  /// targets that support them.
601
  virtual void EmitDTPRel64Value(const MCExpr *Value);
602
603
  /// \brief Emit the expression \p Value into the output as a dtprel
604
  /// (32-bit DTP relative) value.
605
  ///
606
  /// This is used to implement assembler directives such as .dtprelword on
607
  /// targets that support them.
608
  virtual void EmitDTPRel32Value(const MCExpr *Value);
609
610
  /// \brief Emit the expression \p Value into the output as a tprel
611
  /// (64-bit TP relative) value.
612
  ///
613
  /// This is used to implement assembler directives such as .tpreldword on
614
  /// targets that support them.
615
  virtual void EmitTPRel64Value(const MCExpr *Value);
616
617
  /// \brief Emit the expression \p Value into the output as a tprel
618
  /// (32-bit TP relative) value.
619
  ///
620
  /// This is used to implement assembler directives such as .tprelword on
621
  /// targets that support them.
622
  virtual void EmitTPRel32Value(const MCExpr *Value);
623
624
  /// \brief Emit the expression \p Value into the output as a gprel64 (64-bit
625
  /// GP relative) value.
626
  ///
627
  /// This is used to implement assembler directives such as .gpdword on
628
  /// targets that support them.
629
  virtual void EmitGPRel64Value(const MCExpr *Value);
630
631
  /// \brief Emit the expression \p Value into the output as a gprel32 (32-bit
632
  /// GP relative) value.
633
  ///
634
  /// This is used to implement assembler directives such as .gprel32 on
635
  /// targets that support them.
636
  virtual void EmitGPRel32Value(const MCExpr *Value);
637
638
  /// \brief Emit NumBytes bytes worth of the value specified by FillValue.
639
  /// This implements directives such as '.space'.
640
  virtual void emitFill(uint64_t NumBytes, uint8_t FillValue);
641
642
  /// \brief Emit \p Size bytes worth of the value specified by \p FillValue.
643
  ///
644
  /// This is used to implement assembler directives such as .space or .skip.
645
  ///
646
  /// \param NumBytes - The number of bytes to emit.
647
  /// \param FillValue - The value to use when filling bytes.
648
  /// \param Loc - The location of the expression for error reporting.
649
  virtual void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
650
                        SMLoc Loc = SMLoc());
651
652
  /// \brief Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is
653
  /// taken from the lowest order 4 bytes of \p Expr expression.
654
  ///
655
  /// This is used to implement assembler directives such as .fill.
656
  ///
657
  /// \param NumValues - The number of copies of \p Size bytes to emit.
658
  /// \param Size - The size (in bytes) of each repeated value.
659
  /// \param Expr - The expression from which \p Size bytes are used.
660
  virtual void emitFill(uint64_t NumValues, int64_t Size, int64_t Expr);
661
  virtual void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
662
                        SMLoc Loc = SMLoc());
663
664
  /// \brief Emit NumBytes worth of zeros.
665
  /// This function properly handles data in virtual sections.
666
  void EmitZeros(uint64_t NumBytes);
667
668
  /// \brief Emit some number of copies of \p Value until the byte alignment \p
669
  /// ByteAlignment is reached.
670
  ///
671
  /// If the number of bytes need to emit for the alignment is not a multiple
672
  /// of \p ValueSize, then the contents of the emitted fill bytes is
673
  /// undefined.
674
  ///
675
  /// This used to implement the .align assembler directive.
676
  ///
677
  /// \param ByteAlignment - The alignment to reach. This must be a power of
678
  /// two on some targets.
679
  /// \param Value - The value to use when filling bytes.
680
  /// \param ValueSize - The size of the integer (in bytes) to emit for
681
  /// \p Value. This must match a native machine width.
682
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
683
  /// the alignment cannot be reached in this many bytes, no bytes are
684
  /// emitted.
685
  virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
686
                                    unsigned ValueSize = 1,
687
                                    unsigned MaxBytesToEmit = 0);
688
689
  /// \brief Emit nops until the byte alignment \p ByteAlignment is reached.
690
  ///
691
  /// This used to align code where the alignment bytes may be executed.  This
692
  /// can emit different bytes for different sizes to optimize execution.
693
  ///
694
  /// \param ByteAlignment - The alignment to reach. This must be a power of
695
  /// two on some targets.
696
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
697
  /// the alignment cannot be reached in this many bytes, no bytes are
698
  /// emitted.
699
  virtual void EmitCodeAlignment(unsigned ByteAlignment,
700
                                 unsigned MaxBytesToEmit = 0);
701
702
  /// \brief Emit some number of copies of \p Value until the byte offset \p
703
  /// Offset is reached.
704
  ///
705
  /// This is used to implement assembler directives such as .org.
706
  ///
707
  /// \param Offset - The offset to reach. This may be an expression, but the
708
  /// expression must be associated with the current section.
709
  /// \param Value - The value to use when filling bytes.
710
  virtual void emitValueToOffset(const MCExpr *Offset, unsigned char Value,
711
                                 SMLoc Loc);
712
713
  /// @}
714
715
  /// \brief Switch to a new logical file.  This is used to implement the '.file
716
  /// "foo.c"' assembler directive.
717
  virtual void EmitFileDirective(StringRef Filename);
718
719
  /// \brief Emit the "identifiers" directive.  This implements the
720
  /// '.ident "version foo"' assembler directive.
721
3
  virtual void EmitIdent(StringRef IdentString) {}
722
723
  /// \brief Associate a filename with a specified logical file number.  This
724
  /// implements the DWARF2 '.file 4 "foo.c"' assembler directive.
725
  virtual unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
726
                                          StringRef Filename,
727
                                          unsigned CUID = 0);
728
729
  /// \brief This implements the DWARF2 '.loc fileno lineno ...' assembler
730
  /// directive.
731
  virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
732
                                     unsigned Column, unsigned Flags,
733
                                     unsigned Isa, unsigned Discriminator,
734
                                     StringRef FileName);
735
736
  /// Associate a filename with a specified logical file number, and also
737
  /// specify that file's checksum information.  This implements the '.cv_file 4
738
  /// "foo.c"' assembler directive. Returns true on success.
739
  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename,
740
                                   ArrayRef<uint8_t> Checksum,
741
                                   unsigned ChecksumKind);
742
743
  /// \brief Introduces a function id for use with .cv_loc.
744
  virtual bool EmitCVFuncIdDirective(unsigned FunctionId);
745
746
  /// \brief Introduces an inline call site id for use with .cv_loc. Includes
747
  /// extra information for inline line table generation.
748
  virtual bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
749
                                           unsigned IAFile, unsigned IALine,
750
                                           unsigned IACol, SMLoc Loc);
751
752
  /// \brief This implements the CodeView '.cv_loc' assembler directive.
753
  virtual void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
754
                                  unsigned Line, unsigned Column,
755
                                  bool PrologueEnd, bool IsStmt,
756
                                  StringRef FileName, SMLoc Loc);
757
758
  /// \brief This implements the CodeView '.cv_linetable' assembler directive.
759
  virtual void EmitCVLinetableDirective(unsigned FunctionId,
760
                                        const MCSymbol *FnStart,
761
                                        const MCSymbol *FnEnd);
762
763
  /// \brief This implements the CodeView '.cv_inline_linetable' assembler
764
  /// directive.
765
  virtual void EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
766
                                              unsigned SourceFileId,
767
                                              unsigned SourceLineNum,
768
                                              const MCSymbol *FnStartSym,
769
                                              const MCSymbol *FnEndSym);
770
771
  /// \brief This implements the CodeView '.cv_def_range' assembler
772
  /// directive.
773
  virtual void EmitCVDefRangeDirective(
774
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
775
      StringRef FixedSizePortion);
776
777
  /// \brief This implements the CodeView '.cv_stringtable' assembler directive.
778
0
  virtual void EmitCVStringTableDirective() {}
779
780
  /// \brief This implements the CodeView '.cv_filechecksums' assembler directive.
781
0
  virtual void EmitCVFileChecksumsDirective() {}
782
783
  /// This implements the CodeView '.cv_filechecksumoffset' assembler
784
  /// directive.
785
0
  virtual void EmitCVFileChecksumOffsetDirective(unsigned FileNo) {}
786
787
  /// Emit the absolute difference between two symbols.
788
  ///
789
  /// \pre Offset of \c Hi is greater than the offset \c Lo.
790
  virtual void emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
791
                                      unsigned Size);
792
793
  virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
794
  virtual void EmitCFISections(bool EH, bool Debug);
795
  void EmitCFIStartProc(bool IsSimple);
796
  void EmitCFIEndProc();
797
  virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
798
  virtual void EmitCFIDefCfaOffset(int64_t Offset);
799
  virtual void EmitCFIDefCfaRegister(int64_t Register);
800
  virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
801
  virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
802
  virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
803
  virtual void EmitCFIRememberState();
804
  virtual void EmitCFIRestoreState();
805
  virtual void EmitCFISameValue(int64_t Register);
806
  virtual void EmitCFIRestore(int64_t Register);
807
  virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
808
  virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
809
  virtual void EmitCFIEscape(StringRef Values);
810
  virtual void EmitCFIReturnColumn(int64_t Register);
811
  virtual void EmitCFIGnuArgsSize(int64_t Size);
812
  virtual void EmitCFISignalFrame();
813
  virtual void EmitCFIUndefined(int64_t Register);
814
  virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
815
  virtual void EmitCFIWindowSave();
816
817
  virtual void EmitWinCFIStartProc(const MCSymbol *Symbol);
818
  virtual void EmitWinCFIEndProc();
819
  virtual void EmitWinCFIStartChained();
820
  virtual void EmitWinCFIEndChained();
821
  virtual void EmitWinCFIPushReg(unsigned Register);
822
  virtual void EmitWinCFISetFrame(unsigned Register, unsigned Offset);
823
  virtual void EmitWinCFIAllocStack(unsigned Size);
824
  virtual void EmitWinCFISaveReg(unsigned Register, unsigned Offset);
825
  virtual void EmitWinCFISaveXMM(unsigned Register, unsigned Offset);
826
  virtual void EmitWinCFIPushFrame(bool Code);
827
  virtual void EmitWinCFIEndProlog();
828
829
  virtual void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except);
830
  virtual void EmitWinEHHandlerData();
831
832
  /// Get the .pdata section used for the given section. Typically the given
833
  /// section is either the main .text section or some other COMDAT .text
834
  /// section, but it may be any section containing code.
835
  MCSection *getAssociatedPDataSection(const MCSection *TextSec);
836
837
  /// Get the .xdata section used for the given section.
838
  MCSection *getAssociatedXDataSection(const MCSection *TextSec);
839
840
  virtual void EmitSyntaxDirective();
841
842
  /// \brief Emit a .reloc directive.
843
  /// Returns true if the relocation could not be emitted because Name is not
844
  /// known.
845
  virtual bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
846
0
                                  const MCExpr *Expr, SMLoc Loc) {
847
0
    return true;
848
0
  }
849
850
  /// \brief Emit the given \p Instruction into the current section.
851
  /// PrintSchedInfo == true then schedul comment should be added to output
852
  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
853
                               bool PrintSchedInfo = false);
854
855
  /// \brief Set the bundle alignment mode from now on in the section.
856
  /// The argument is the power of 2 to which the alignment is set. The
857
  /// value 0 means turn the bundle alignment off.
858
  virtual void EmitBundleAlignMode(unsigned AlignPow2);
859
860
  /// \brief The following instructions are a bundle-locked group.
861
  ///
862
  /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
863
  ///                     the end of a bundle.
864
  virtual void EmitBundleLock(bool AlignToEnd);
865
866
  /// \brief Ends a bundle-locked group.
867
  virtual void EmitBundleUnlock();
868
869
  /// \brief If this file is backed by a assembly streamer, this dumps the
870
  /// specified string in the output .s file.  This capability is indicated by
871
  /// the hasRawTextSupport() predicate.  By default this aborts.
872
  void EmitRawText(const Twine &String);
873
874
  /// \brief Streamer specific finalization.
875
  virtual void FinishImpl();
876
  /// \brief Finish emission of machine code.
877
  void Finish();
878
879
5
  virtual bool mayHaveInstructions(MCSection &Sec) const { return true; }
880
};
881
882
/// Create a dummy machine code streamer, which does nothing. This is useful for
883
/// timing the assembler front end.
884
MCStreamer *createNullStreamer(MCContext &Ctx);
885
886
/// Create a machine code streamer which will print out assembly for the native
887
/// target, suitable for compiling with a native assembler.
888
///
889
/// \param InstPrint - If given, the instruction printer to use. If not given
890
/// the MCInst representation will be printed.  This method takes ownership of
891
/// InstPrint.
892
///
893
/// \param CE - If given, a code emitter to use to show the instruction
894
/// encoding inline with the assembly. This method takes ownership of \p CE.
895
///
896
/// \param TAB - If given, a target asm backend to use to show the fixup
897
/// information in conjunction with encoding information. This method takes
898
/// ownership of \p TAB.
899
///
900
/// \param ShowInst - Whether to show the MCInst representation inline with
901
/// the assembly.
902
MCStreamer *createAsmStreamer(MCContext &Ctx,
903
                              std::unique_ptr<formatted_raw_ostream> OS,
904
                              bool isVerboseAsm, bool useDwarfDirectory,
905
                              MCInstPrinter *InstPrint, MCCodeEmitter *CE,
906
                              MCAsmBackend *TAB, bool ShowInst);
907
908
} // end namespace llvm
909
910
#endif // LLVM_MC_MCSTREAMER_H