Coverage Report

Created: 2018-07-19 03:59

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/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/Optional.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/Error.h"
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#include "llvm/Support/MD5.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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38
namespace llvm {
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40
class AssemblerConstantPools;
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class formatted_raw_ostream;
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class MCAsmBackend;
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class MCCodeEmitter;
44
struct MCCodePaddingContext;
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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;
50
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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58
/// Target specific streamer interface. This is used so that targets can
59
/// implement support for target specific assembly directives.
60
///
61
/// 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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///
66
/// FooTargetStreamer should have a pure virtual method for each directive. For
67
/// 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
71
/// 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
75
/// calling getTargetStreamer and casting it to FooTargetStreamer:
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///
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/// MCTargetStreamer &TS = OutStreamer.getTargetStreamer();
78
/// FooTargetStreamer &ATS = static_cast<FooTargetStreamer &>(TS);
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///
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/// The base classes FooTargetAsmStreamer and FooTargetELFStreamer should
81
/// *never* be treated differently. Callers should always talk to a
82
/// FooTargetStreamer.
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class MCTargetStreamer {
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protected:
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  MCStreamer &Streamer;
86
87
public:
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  MCTargetStreamer(MCStreamer &S);
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  virtual ~MCTargetStreamer();
90
91
12.6k
  MCStreamer &getStreamer() { return Streamer; }
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93
  // Allow a target to add behavior to the EmitLabel of MCStreamer.
94
  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,
99
                              const MCInst &Inst, const MCSubtargetInfo &STI);
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101
  virtual void emitDwarfFileDirective(StringRef Directive);
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103
  /// Update streamer for a new active section.
104
  ///
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  /// This is called by PopSection and SwitchSection, if the current
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  /// section changes.
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  virtual void changeSection(const MCSection *CurSection, MCSection *Section,
108
                             const MCExpr *SubSection, raw_ostream &OS);
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110
  virtual void emitValue(const MCExpr *Value);
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112
  virtual void finish();
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};
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// FIXME: declared here because it is used from
116
// lib/CodeGen/AsmPrinter/ARMException.cpp.
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class ARMTargetStreamer : public MCTargetStreamer {
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public:
119
  ARMTargetStreamer(MCStreamer &S);
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  ~ARMTargetStreamer() override;
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122
  virtual void emitFnStart();
123
  virtual void emitFnEnd();
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  virtual void emitCantUnwind();
125
  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,
129
                         int64_t Offset = 0);
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  virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
131
  virtual void emitPad(int64_t Offset);
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  virtual void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
133
                           bool isVector);
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  virtual void emitUnwindRaw(int64_t StackOffset,
135
                             const SmallVectorImpl<uint8_t> &Opcodes);
136
137
  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);
140
  virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
141
                                    StringRef StringValue = "");
142
  virtual void emitFPU(unsigned FPU);
143
  virtual void emitArch(ARM::ArchKind Arch);
144
  virtual void emitArchExtension(unsigned ArchExt);
145
  virtual void emitObjectArch(ARM::ArchKind Arch);
146
  void emitTargetAttributes(const MCSubtargetInfo &STI);
147
  virtual void finishAttributeSection();
148
  virtual void emitInst(uint32_t Inst, char Suffix = '\0');
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150
  virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
151
152
  virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value);
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154
  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.
163
  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.
167
  void emitCurrentConstantPool();
168
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private:
170
  std::unique_ptr<AssemblerConstantPools> ConstantPools;
171
};
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/// Streaming machine code generation interface.
174
///
175
/// 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
177
/// 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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///
180
/// 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.
182
///
183
class MCStreamer {
184
  MCContext &Context;
185
  std::unique_ptr<MCTargetStreamer> TargetStreamer;
186
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  std::vector<MCDwarfFrameInfo> DwarfFrameInfos;
188
  MCDwarfFrameInfo *getCurrentDwarfFrameInfo();
189
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  /// Similar to DwarfFrameInfos, but for SEH unwind info. Chained frames may
191
  /// refer to each other, so use std::unique_ptr to provide pointer stability.
192
  std::vector<std::unique_ptr<WinEH::FrameInfo>> WinFrameInfos;
193
194
  WinEH::FrameInfo *CurrentWinFrameInfo;
195
196
  /// Retreive the current frame info if one is available and it is not yet
197
  /// closed. Otherwise, issue an error and return null.
198
  WinEH::FrameInfo *EnsureValidWinFrameInfo(SMLoc Loc);
199
200
  /// Tracks an index to represent the order a symbol was emitted in.
201
  /// Zero means we did not emit that symbol.
202
  DenseMap<const MCSymbol *, unsigned> SymbolOrdering;
203
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  /// This is stack of current and previous section values saved by
205
  /// PushSection.
206
  SmallVector<std::pair<MCSectionSubPair, MCSectionSubPair>, 4> SectionStack;
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  /// The next unique ID to use when creating a WinCFI-related section (.pdata
209
  /// 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
211
  /// requires.
212
  unsigned NextWinCFIID = 0;
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  bool UseAssemblerInfoForParsing;
215
216
protected:
217
  MCStreamer(MCContext &Ctx);
218
219
  virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
220
  virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
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  /// When emitting an object file, create and emit a real label. When emitting
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  /// textual assembly, this should do nothing to avoid polluting our output.
224
  virtual MCSymbol *EmitCFILabel();
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545
  WinEH::FrameInfo *getCurrentWinFrameInfo() {
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545
    return CurrentWinFrameInfo;
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545
  }
229
230
  virtual void EmitWindowsUnwindTables();
231
232
  virtual void EmitRawTextImpl(StringRef String);
233
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public:
235
  MCStreamer(const MCStreamer &) = delete;
236
  MCStreamer &operator=(const MCStreamer &) = delete;
237
  virtual ~MCStreamer();
238
239
  void visitUsedExpr(const MCExpr &Expr);
240
  virtual void visitUsedSymbol(const MCSymbol &Sym);
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25.9k
  void setTargetStreamer(MCTargetStreamer *TS) {
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25.9k
    TargetStreamer.reset(TS);
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25.9k
  }
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  /// State management
247
  ///
248
  virtual void reset();
249
250
81.8M
  MCContext &getContext() const { return Context; }
251
252
193
  virtual MCAssembler *getAssemblerPtr() { return nullptr; }
253
254
17.6k
  void setUseAssemblerInfoForParsing(bool v) { UseAssemblerInfoForParsing = v; }
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2.64M
  bool getUseAssemblerInfoForParsing() { return UseAssemblerInfoForParsing; }
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12.2M
  MCTargetStreamer *getTargetStreamer() {
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12.2M
    return TargetStreamer.get();
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12.2M
  }
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22.7k
  unsigned getNumFrameInfos() { return DwarfFrameInfos.size(); }
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9.46k
  ArrayRef<MCDwarfFrameInfo> getDwarfFrameInfos() const {
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9.46k
    return DwarfFrameInfos;
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9.46k
  }
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  bool hasUnfinishedDwarfFrameInfo();
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  unsigned getNumWinFrameInfos() { return WinFrameInfos.size(); }
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  ArrayRef<std::unique_ptr<WinEH::FrameInfo>> getWinFrameInfos() const {
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    return WinFrameInfos;
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100
  }
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  void generateCompactUnwindEncodings(MCAsmBackend *MAB);
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  /// \name Assembly File Formatting.
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  /// @{
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  /// Return true if this streamer supports verbose assembly and if it is
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  /// enabled.
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41.1k
  virtual bool isVerboseAsm() const { return false; }
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  /// Return true if this asm streamer supports emitting unformatted text
283
  /// to the .s file with EmitRawText.
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1.39M
  virtual bool hasRawTextSupport() const { return false; }
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286
  /// Is the integrated assembler required for this streamer to function
287
  /// correctly?
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1.81k
  virtual bool isIntegratedAssemblerRequired() const { return false; }
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  /// Add a textual comment.
291
  ///
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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
298
  /// prefix as appropriate.  The added comment should not end with a \n.
299
  /// By default, each comment is terminated with an end of line, i.e. the
300
  /// EOL param is set to true by default. If one prefers not to end the 
301
  /// comment with a new line then the EOL param should be passed 
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  /// with a false value.
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739k
  virtual void AddComment(const Twine &T, bool EOL = true) {}
304
305
  /// Return a raw_ostream that comments can be written to. Unlike
306
  /// AddComment, you are required to terminate comments with \n if you use this
307
  /// method.
308
  virtual raw_ostream &GetCommentOS();
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  /// Print T and prefix it with the comment string (normally #) and
311
  /// optionally a tab. This prints the comment immediately, not at the end of
312
  /// the current line. It is basically a safe version of EmitRawText: since it
313
  /// only prints comments, the object streamer ignores it instead of asserting.
314
  virtual void emitRawComment(const Twine &T, bool TabPrefix = true);
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  /// 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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  /// Emit added explicit comments.
321
  virtual void emitExplicitComments();
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  /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
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952k
  virtual void AddBlankLine() {}
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  /// @}
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328
  /// \name Symbol & Section Management
329
  /// @{
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331
  /// Return the current section that the streamer is emitting code to.
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110M
  MCSectionSubPair getCurrentSection() const {
333
110M
    if (!SectionStack.empty())
334
110M
      return SectionStack.back().first;
335
18.4E
    return MCSectionSubPair();
336
18.4E
  }
337
110M
  MCSection *getCurrentSectionOnly() const { return getCurrentSection().first; }
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339
  /// Return the previous section that the streamer is emitting code to.
340
15.3k
  MCSectionSubPair getPreviousSection() const {
341
15.3k
    if (!SectionStack.empty())
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15.3k
      return SectionStack.back().second;
343
0
    return MCSectionSubPair();
344
0
  }
345
346
  /// Returns an index to represent the order a symbol was emitted in.
347
  /// (zero if we did not emit that symbol)
348
14
  unsigned GetSymbolOrder(const MCSymbol *Sym) const {
349
14
    return SymbolOrdering.lookup(Sym);
350
14
  }
351
352
  /// Update streamer for a new active section.
353
  ///
354
  /// This is called by PopSection and SwitchSection, if the current
355
  /// section changes.
356
  virtual void ChangeSection(MCSection *, const MCExpr *);
357
358
  /// Save the current and previous section on the section stack.
359
8.36k
  void PushSection() {
360
8.36k
    SectionStack.push_back(
361
8.36k
        std::make_pair(getCurrentSection(), getPreviousSection()));
362
8.36k
  }
363
364
  /// Restore the current and previous section from the section stack.
365
  /// Calls ChangeSection as needed.
366
  ///
367
  /// Returns false if the stack was empty.
368
8.36k
  bool PopSection() {
369
8.36k
    if (SectionStack.size() <= 1)
370
0
      return false;
371
8.36k
    auto I = SectionStack.end();
372
8.36k
    --I;
373
8.36k
    MCSectionSubPair OldSection = I->first;
374
8.36k
    --I;
375
8.36k
    MCSectionSubPair NewSection = I->first;
376
8.36k
377
8.36k
    if (OldSection != NewSection)
378
8.08k
      ChangeSection(NewSection.first, NewSection.second);
379
8.36k
    SectionStack.pop_back();
380
8.36k
    return true;
381
8.36k
  }
382
383
4
  bool SubSection(const MCExpr *Subsection) {
384
4
    if (SectionStack.empty())
385
0
      return false;
386
4
387
4
    SwitchSection(SectionStack.back().first.first, Subsection);
388
4
    return true;
389
4
  }
390
391
  /// Set the current section where code is being emitted to \p Section.  This
392
  /// is required to update CurSection.
393
  ///
394
  /// This corresponds to assembler directives like .section, .text, etc.
395
  virtual void SwitchSection(MCSection *Section,
396
                             const MCExpr *Subsection = nullptr);
397
398
  /// Set the current section where code is being emitted to \p Section.
399
  /// This is required to update CurSection. This version does not call
400
  /// ChangeSection.
401
  void SwitchSectionNoChange(MCSection *Section,
402
460
                             const MCExpr *Subsection = nullptr) {
403
460
    assert(Section && "Cannot switch to a null section!");
404
460
    MCSectionSubPair curSection = SectionStack.back().first;
405
460
    SectionStack.back().second = curSection;
406
460
    if (MCSectionSubPair(Section, Subsection) != curSection)
407
460
      SectionStack.back().first = MCSectionSubPair(Section, Subsection);
408
460
  }
409
410
  /// Create the default sections and set the initial one.
411
  virtual void InitSections(bool NoExecStack);
412
413
  MCSymbol *endSection(MCSection *Section);
414
415
  /// Sets the symbol's section.
416
  ///
417
  /// Each emitted symbol will be tracked in the ordering table,
418
  /// so we can sort on them later.
419
  void AssignFragment(MCSymbol *Symbol, MCFragment *Fragment);
420
421
  /// Emit a label for \p Symbol into the current section.
422
  ///
423
  /// This corresponds to an assembler statement such as:
424
  ///   foo:
425
  ///
426
  /// \param Symbol - The symbol to emit. A given symbol should only be
427
  /// emitted as a label once, and symbols emitted as a label should never be
428
  /// used in an assignment.
429
  // FIXME: These emission are non-const because we mutate the symbol to
430
  // add the section we're emitting it to later.
431
  virtual void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc());
432
433
  virtual void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol);
434
435
  /// Note in the output the specified \p Flag.
436
  virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
437
438
  /// Emit the given list \p Options of strings as linker
439
  /// options into the output.
440
0
  virtual void EmitLinkerOptions(ArrayRef<std::string> Kind) {}
441
442
  /// Note in the output the specified region \p Kind.
443
136
  virtual void EmitDataRegion(MCDataRegionType Kind) {}
444
445
  /// Specify the Mach-O minimum deployment target version.
446
  virtual void EmitVersionMin(MCVersionMinType Type, unsigned Major,
447
2
                              unsigned Minor, unsigned Update) {}
448
449
  /// Emit/Specify Mach-O build version command.
450
  /// \p Platform should be one of MachO::PlatformType.
451
  virtual void EmitBuildVersion(unsigned Platform, unsigned Major,
452
0
                                unsigned Minor, unsigned Update) {}
453
454
  void EmitVersionForTarget(const Triple &Target);
455
456
  /// Note in the output that the specified \p Func is a Thumb mode
457
  /// function (ARM target only).
458
  virtual void EmitThumbFunc(MCSymbol *Func);
459
460
  /// Emit an assignment of \p Value to \p Symbol.
461
  ///
462
  /// This corresponds to an assembler statement such as:
463
  ///  symbol = value
464
  ///
465
  /// The assignment generates no code, but has the side effect of binding the
466
  /// value in the current context. For the assembly streamer, this prints the
467
  /// binding into the .s file.
468
  ///
469
  /// \param Symbol - The symbol being assigned to.
470
  /// \param Value - The value for the symbol.
471
  virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
472
473
  /// Emit an weak reference from \p Alias to \p Symbol.
474
  ///
475
  /// This corresponds to an assembler statement such as:
476
  ///  .weakref alias, symbol
477
  ///
478
  /// \param Alias - The alias that is being created.
479
  /// \param Symbol - The symbol being aliased.
480
  virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
481
482
  /// Add the given \p Attribute to \p Symbol.
483
  virtual bool EmitSymbolAttribute(MCSymbol *Symbol,
484
                                   MCSymbolAttr Attribute) = 0;
485
486
  /// Set the \p DescValue for the \p Symbol.
487
  ///
488
  /// \param Symbol - The symbol to have its n_desc field set.
489
  /// \param DescValue - The value to set into the n_desc field.
490
  virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
491
492
  /// Start emitting COFF symbol definition
493
  ///
494
  /// \param Symbol - The symbol to have its External & Type fields set.
495
  virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
496
497
  /// Emit the storage class of the symbol.
498
  ///
499
  /// \param StorageClass - The storage class the symbol should have.
500
  virtual void EmitCOFFSymbolStorageClass(int StorageClass);
501
502
  /// Emit the type of the symbol.
503
  ///
504
  /// \param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
505
  virtual void EmitCOFFSymbolType(int Type);
506
507
  /// Marks the end of the symbol definition.
508
  virtual void EndCOFFSymbolDef();
509
510
  virtual void EmitCOFFSafeSEH(MCSymbol const *Symbol);
511
512
  /// Emits the symbol table index of a Symbol into the current section.
513
  virtual void EmitCOFFSymbolIndex(MCSymbol const *Symbol);
514
515
  /// Emits a COFF section index.
516
  ///
517
  /// \param Symbol - Symbol the section number relocation should point to.
518
  virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
519
520
  /// Emits a COFF section relative relocation.
521
  ///
522
  /// \param Symbol - Symbol the section relative relocation should point to.
523
  virtual void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset);
524
525
  /// Emit an ELF .size directive.
526
  ///
527
  /// This corresponds to an assembler statement such as:
528
  ///  .size symbol, expression
529
  virtual void emitELFSize(MCSymbol *Symbol, const MCExpr *Value);
530
531
  /// Emit an ELF .symver directive.
532
  ///
533
  /// This corresponds to an assembler statement such as:
534
  ///  .symver _start, foo@@SOME_VERSION
535
  /// \param AliasName - The versioned alias (i.e. "foo@@SOME_VERSION")
536
  /// \param Aliasee - The aliased symbol (i.e. "_start")
537
  virtual void emitELFSymverDirective(StringRef AliasName,
538
                                      const MCSymbol *Aliasee);
539
540
  /// Emit a Linker Optimization Hint (LOH) directive.
541
  /// \param Args - Arguments of the LOH.
542
0
  virtual void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {}
543
544
  /// Emit a common symbol.
545
  ///
546
  /// \param Symbol - The common symbol to emit.
547
  /// \param Size - The size of the common symbol.
548
  /// \param ByteAlignment - The alignment of the symbol if
549
  /// non-zero. This must be a power of 2.
550
  virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
551
                                unsigned ByteAlignment) = 0;
552
553
  /// Emit a local common (.lcomm) symbol.
554
  ///
555
  /// \param Symbol - The common symbol to emit.
556
  /// \param Size - The size of the common symbol.
557
  /// \param ByteAlignment - The alignment of the common symbol in bytes.
558
  virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
559
                                     unsigned ByteAlignment);
560
561
  /// Emit the zerofill section and an optional symbol.
562
  ///
563
  /// \param Section - The zerofill section to create and or to put the symbol
564
  /// \param Symbol - The zerofill symbol to emit, if non-NULL.
565
  /// \param Size - The size of the zerofill symbol.
566
  /// \param ByteAlignment - The alignment of the zerofill symbol if
567
  /// non-zero. This must be a power of 2 on some targets.
568
  virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
569
                            uint64_t Size = 0, unsigned ByteAlignment = 0,
570
                            SMLoc Loc = SMLoc()) = 0;
571
572
  /// Emit a thread local bss (.tbss) symbol.
573
  ///
574
  /// \param Section - The thread local common section.
575
  /// \param Symbol - The thread local common symbol to emit.
576
  /// \param Size - The size of the symbol.
577
  /// \param ByteAlignment - The alignment of the thread local common symbol
578
  /// if non-zero.  This must be a power of 2 on some targets.
579
  virtual void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
580
                              uint64_t Size, unsigned ByteAlignment = 0);
581
582
  /// @}
583
  /// \name Generating Data
584
  /// @{
585
586
  /// Emit the bytes in \p Data into the output.
587
  ///
588
  /// This is used to implement assembler directives such as .byte, .ascii,
589
  /// etc.
590
  virtual void EmitBytes(StringRef Data);
591
592
  /// Functionally identical to EmitBytes. When emitting textual assembly, this
593
  /// method uses .byte directives instead of .ascii or .asciz for readability.
594
  virtual void EmitBinaryData(StringRef Data);
595
596
  /// Emit the expression \p Value into the output as a native
597
  /// integer of the given \p Size bytes.
598
  ///
599
  /// This is used to implement assembler directives such as .word, .quad,
600
  /// etc.
601
  ///
602
  /// \param Value - The value to emit.
603
  /// \param Size - The size of the integer (in bytes) to emit. This must
604
  /// match a native machine width.
605
  /// \param Loc - The location of the expression for error reporting.
606
  virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
607
                             SMLoc Loc = SMLoc());
608
609
  void EmitValue(const MCExpr *Value, unsigned Size, SMLoc Loc = SMLoc());
610
611
  /// Special case of EmitValue that avoids the client having
612
  /// to pass in a MCExpr for constant integers.
613
  virtual void EmitIntValue(uint64_t Value, unsigned Size);
614
615
  virtual void EmitULEB128Value(const MCExpr *Value);
616
617
  virtual void EmitSLEB128Value(const MCExpr *Value);
618
619
  /// Special case of EmitULEB128Value that avoids the client having to
620
  /// pass in a MCExpr for constant integers.
621
  void EmitULEB128IntValue(uint64_t Value);
622
623
  /// Special case of EmitSLEB128Value that avoids the client having to
624
  /// pass in a MCExpr for constant integers.
625
  void EmitSLEB128IntValue(int64_t Value);
626
627
  /// Special case of EmitValue that avoids the client having to pass in
628
  /// a MCExpr for MCSymbols.
629
  void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
630
                       bool IsSectionRelative = false);
631
632
  /// Emit the expression \p Value into the output as a dtprel
633
  /// (64-bit DTP relative) value.
634
  ///
635
  /// This is used to implement assembler directives such as .dtpreldword on
636
  /// targets that support them.
637
  virtual void EmitDTPRel64Value(const MCExpr *Value);
638
639
  /// Emit the expression \p Value into the output as a dtprel
640
  /// (32-bit DTP relative) value.
641
  ///
642
  /// This is used to implement assembler directives such as .dtprelword on
643
  /// targets that support them.
644
  virtual void EmitDTPRel32Value(const MCExpr *Value);
645
646
  /// Emit the expression \p Value into the output as a tprel
647
  /// (64-bit TP relative) value.
648
  ///
649
  /// This is used to implement assembler directives such as .tpreldword on
650
  /// targets that support them.
651
  virtual void EmitTPRel64Value(const MCExpr *Value);
652
653
  /// Emit the expression \p Value into the output as a tprel
654
  /// (32-bit TP relative) value.
655
  ///
656
  /// This is used to implement assembler directives such as .tprelword on
657
  /// targets that support them.
658
  virtual void EmitTPRel32Value(const MCExpr *Value);
659
660
  /// Emit the expression \p Value into the output as a gprel64 (64-bit
661
  /// GP relative) value.
662
  ///
663
  /// This is used to implement assembler directives such as .gpdword on
664
  /// targets that support them.
665
  virtual void EmitGPRel64Value(const MCExpr *Value);
666
667
  /// Emit the expression \p Value into the output as a gprel32 (32-bit
668
  /// GP relative) value.
669
  ///
670
  /// This is used to implement assembler directives such as .gprel32 on
671
  /// targets that support them.
672
  virtual void EmitGPRel32Value(const MCExpr *Value);
673
674
  /// Emit NumBytes bytes worth of the value specified by FillValue.
675
  /// This implements directives such as '.space'.
676
  void emitFill(uint64_t NumBytes, uint8_t FillValue);
677
678
  /// Emit \p Size bytes worth of the value specified by \p FillValue.
679
  ///
680
  /// This is used to implement assembler directives such as .space or .skip.
681
  ///
682
  /// \param NumBytes - The number of bytes to emit.
683
  /// \param FillValue - The value to use when filling bytes.
684
  /// \param Loc - The location of the expression for error reporting.
685
  virtual void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
686
                        SMLoc Loc = SMLoc());
687
688
  /// Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is
689
  /// taken from the lowest order 4 bytes of \p Expr expression.
690
  ///
691
  /// This is used to implement assembler directives such as .fill.
692
  ///
693
  /// \param NumValues - The number of copies of \p Size bytes to emit.
694
  /// \param Size - The size (in bytes) of each repeated value.
695
  /// \param Expr - The expression from which \p Size bytes are used.
696
  virtual void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
697
                        SMLoc Loc = SMLoc());
698
699
  /// Emit NumBytes worth of zeros.
700
  /// This function properly handles data in virtual sections.
701
  void EmitZeros(uint64_t NumBytes);
702
703
  /// Emit some number of copies of \p Value until the byte alignment \p
704
  /// ByteAlignment is reached.
705
  ///
706
  /// If the number of bytes need to emit for the alignment is not a multiple
707
  /// of \p ValueSize, then the contents of the emitted fill bytes is
708
  /// undefined.
709
  ///
710
  /// This used to implement the .align assembler directive.
711
  ///
712
  /// \param ByteAlignment - The alignment to reach. This must be a power of
713
  /// two on some targets.
714
  /// \param Value - The value to use when filling bytes.
715
  /// \param ValueSize - The size of the integer (in bytes) to emit for
716
  /// \p Value. This must match a native machine width.
717
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
718
  /// the alignment cannot be reached in this many bytes, no bytes are
719
  /// emitted.
720
  virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
721
                                    unsigned ValueSize = 1,
722
                                    unsigned MaxBytesToEmit = 0);
723
724
  /// Emit nops until the byte alignment \p ByteAlignment is reached.
725
  ///
726
  /// This used to align code where the alignment bytes may be executed.  This
727
  /// can emit different bytes for different sizes to optimize execution.
728
  ///
729
  /// \param ByteAlignment - The alignment to reach. This must be a power of
730
  /// two on some targets.
731
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
732
  /// the alignment cannot be reached in this many bytes, no bytes are
733
  /// emitted.
734
  virtual void EmitCodeAlignment(unsigned ByteAlignment,
735
                                 unsigned MaxBytesToEmit = 0);
736
737
  /// Emit some number of copies of \p Value until the byte offset \p
738
  /// Offset is reached.
739
  ///
740
  /// This is used to implement assembler directives such as .org.
741
  ///
742
  /// \param Offset - The offset to reach. This may be an expression, but the
743
  /// expression must be associated with the current section.
744
  /// \param Value - The value to use when filling bytes.
745
  virtual void emitValueToOffset(const MCExpr *Offset, unsigned char Value,
746
                                 SMLoc Loc);
747
748
  virtual void
749
219k
  EmitCodePaddingBasicBlockStart(const MCCodePaddingContext &Context) {}
750
751
  virtual void
752
219k
  EmitCodePaddingBasicBlockEnd(const MCCodePaddingContext &Context) {}
753
754
  /// @}
755
756
  /// Switch to a new logical file.  This is used to implement the '.file
757
  /// "foo.c"' assembler directive.
758
  virtual void EmitFileDirective(StringRef Filename);
759
760
  /// Emit the "identifiers" directive.  This implements the
761
  /// '.ident "version foo"' assembler directive.
762
3
  virtual void EmitIdent(StringRef IdentString) {}
763
764
  /// Associate a filename with a specified logical file number.  This
765
  /// implements the DWARF2 '.file 4 "foo.c"' assembler directive.
766
  unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
767
                                  StringRef Filename,
768
                                  MD5::MD5Result *Checksum = nullptr,
769
                                  Optional<StringRef> Source = None,
770
1.35M
                                  unsigned CUID = 0) {
771
1.35M
    return cantFail(
772
1.35M
        tryEmitDwarfFileDirective(FileNo, Directory, Filename, Checksum,
773
1.35M
                                  Source, CUID));
774
1.35M
  }
775
776
  /// Associate a filename with a specified logical file number.
777
  /// Also associate a directory, optional checksum, and optional source
778
  /// text with the logical file.  This implements the DWARF2
779
  /// '.file 4 "dir/foo.c"' assembler directive, and the DWARF5
780
  /// '.file 4 "dir/foo.c" md5 "..." source "..."' assembler directive.
781
  virtual Expected<unsigned> tryEmitDwarfFileDirective(
782
      unsigned FileNo, StringRef Directory, StringRef Filename,
783
      MD5::MD5Result *Checksum = nullptr, Optional<StringRef> Source = None,
784
      unsigned CUID = 0);
785
786
  /// Specify the "root" file of the compilation, using the ".file 0" extension.
787
  virtual void emitDwarfFile0Directive(StringRef Directory, StringRef Filename,
788
                                       MD5::MD5Result *Checksum,
789
                                       Optional<StringRef> Source,
790
                                       unsigned CUID = 0);
791
792
  /// This implements the DWARF2 '.loc fileno lineno ...' assembler
793
  /// directive.
794
  virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
795
                                     unsigned Column, unsigned Flags,
796
                                     unsigned Isa, unsigned Discriminator,
797
                                     StringRef FileName);
798
799
  /// Associate a filename with a specified logical file number, and also
800
  /// specify that file's checksum information.  This implements the '.cv_file 4
801
  /// "foo.c"' assembler directive. Returns true on success.
802
  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename,
803
                                   ArrayRef<uint8_t> Checksum,
804
                                   unsigned ChecksumKind);
805
806
  /// Introduces a function id for use with .cv_loc.
807
  virtual bool EmitCVFuncIdDirective(unsigned FunctionId);
808
809
  /// Introduces an inline call site id for use with .cv_loc. Includes
810
  /// extra information for inline line table generation.
811
  virtual bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
812
                                           unsigned IAFile, unsigned IALine,
813
                                           unsigned IACol, SMLoc Loc);
814
815
  /// This implements the CodeView '.cv_loc' assembler directive.
816
  virtual void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
817
                                  unsigned Line, unsigned Column,
818
                                  bool PrologueEnd, bool IsStmt,
819
                                  StringRef FileName, SMLoc Loc);
820
821
  /// This implements the CodeView '.cv_linetable' assembler directive.
822
  virtual void EmitCVLinetableDirective(unsigned FunctionId,
823
                                        const MCSymbol *FnStart,
824
                                        const MCSymbol *FnEnd);
825
826
  /// This implements the CodeView '.cv_inline_linetable' assembler
827
  /// directive.
828
  virtual void EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
829
                                              unsigned SourceFileId,
830
                                              unsigned SourceLineNum,
831
                                              const MCSymbol *FnStartSym,
832
                                              const MCSymbol *FnEndSym);
833
834
  /// This implements the CodeView '.cv_def_range' assembler
835
  /// directive.
836
  virtual void EmitCVDefRangeDirective(
837
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
838
      StringRef FixedSizePortion);
839
840
  /// This implements the CodeView '.cv_stringtable' assembler directive.
841
0
  virtual void EmitCVStringTableDirective() {}
842
843
  /// This implements the CodeView '.cv_filechecksums' assembler directive.
844
0
  virtual void EmitCVFileChecksumsDirective() {}
845
846
  /// This implements the CodeView '.cv_filechecksumoffset' assembler
847
  /// directive.
848
0
  virtual void EmitCVFileChecksumOffsetDirective(unsigned FileNo) {}
849
850
  /// This implements the CodeView '.cv_fpo_data' assembler directive.
851
0
  virtual void EmitCVFPOData(const MCSymbol *ProcSym, SMLoc Loc = {}) {}
852
853
  /// Emit the absolute difference between two symbols.
854
  ///
855
  /// \pre Offset of \c Hi is greater than the offset \c Lo.
856
  virtual void emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
857
                                      unsigned Size);
858
859
  /// Emit the absolute difference between two symbols encoded with ULEB128.
860
  virtual void emitAbsoluteSymbolDiffAsULEB128(const MCSymbol *Hi,
861
                                               const MCSymbol *Lo);
862
863
  virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
864
  virtual void EmitCFISections(bool EH, bool Debug);
865
  void EmitCFIStartProc(bool IsSimple);
866
  void EmitCFIEndProc();
867
  virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
868
  virtual void EmitCFIDefCfaOffset(int64_t Offset);
869
  virtual void EmitCFIDefCfaRegister(int64_t Register);
870
  virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
871
  virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
872
  virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
873
  virtual void EmitCFIRememberState();
874
  virtual void EmitCFIRestoreState();
875
  virtual void EmitCFISameValue(int64_t Register);
876
  virtual void EmitCFIRestore(int64_t Register);
877
  virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
878
  virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
879
  virtual void EmitCFIEscape(StringRef Values);
880
  virtual void EmitCFIReturnColumn(int64_t Register);
881
  virtual void EmitCFIGnuArgsSize(int64_t Size);
882
  virtual void EmitCFISignalFrame();
883
  virtual void EmitCFIUndefined(int64_t Register);
884
  virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
885
  virtual void EmitCFIWindowSave();
886
887
  virtual void EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc = SMLoc());
888
  virtual void EmitWinCFIEndProc(SMLoc Loc = SMLoc());
889
  virtual void EmitWinCFIStartChained(SMLoc Loc = SMLoc());
890
  virtual void EmitWinCFIEndChained(SMLoc Loc = SMLoc());
891
  virtual void EmitWinCFIPushReg(unsigned Register, SMLoc Loc = SMLoc());
892
  virtual void EmitWinCFISetFrame(unsigned Register, unsigned Offset,
893
                                  SMLoc Loc = SMLoc());
894
  virtual void EmitWinCFIAllocStack(unsigned Size, SMLoc Loc = SMLoc());
895
  virtual void EmitWinCFISaveReg(unsigned Register, unsigned Offset,
896
                                 SMLoc Loc = SMLoc());
897
  virtual void EmitWinCFISaveXMM(unsigned Register, unsigned Offset,
898
                                 SMLoc Loc = SMLoc());
899
  virtual void EmitWinCFIPushFrame(bool Code, SMLoc Loc = SMLoc());
900
  virtual void EmitWinCFIEndProlog(SMLoc Loc = SMLoc());
901
  virtual void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except,
902
                                SMLoc Loc = SMLoc());
903
  virtual void EmitWinEHHandlerData(SMLoc Loc = SMLoc());
904
905
  virtual void emitCGProfileEntry(const MCSymbolRefExpr *From,
906
                                  const MCSymbolRefExpr *To, uint64_t Count);
907
908
  /// Get the .pdata section used for the given section. Typically the given
909
  /// section is either the main .text section or some other COMDAT .text
910
  /// section, but it may be any section containing code.
911
  MCSection *getAssociatedPDataSection(const MCSection *TextSec);
912
913
  /// Get the .xdata section used for the given section.
914
  MCSection *getAssociatedXDataSection(const MCSection *TextSec);
915
916
  virtual void EmitSyntaxDirective();
917
918
  /// Emit a .reloc directive.
919
  /// Returns true if the relocation could not be emitted because Name is not
920
  /// known.
921
  virtual bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
922
                                  const MCExpr *Expr, SMLoc Loc,
923
0
                                  const MCSubtargetInfo &STI) {
924
0
    return true;
925
0
  }
926
927
0
  virtual void EmitAddrsig() {}
928
0
  virtual void EmitAddrsigSym(const MCSymbol *Sym) {}
929
930
  /// Emit the given \p Instruction into the current section.
931
  /// PrintSchedInfo == true then schedul comment should be added to output
932
  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
933
                               bool PrintSchedInfo = false);
934
935
  /// Set the bundle alignment mode from now on in the section.
936
  /// The argument is the power of 2 to which the alignment is set. The
937
  /// value 0 means turn the bundle alignment off.
938
  virtual void EmitBundleAlignMode(unsigned AlignPow2);
939
940
  /// The following instructions are a bundle-locked group.
941
  ///
942
  /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
943
  ///                     the end of a bundle.
944
  virtual void EmitBundleLock(bool AlignToEnd);
945
946
  /// Ends a bundle-locked group.
947
  virtual void EmitBundleUnlock();
948
949
  /// If this file is backed by a assembly streamer, this dumps the
950
  /// specified string in the output .s file.  This capability is indicated by
951
  /// the hasRawTextSupport() predicate.  By default this aborts.
952
  void EmitRawText(const Twine &String);
953
954
  /// Streamer specific finalization.
955
  virtual void FinishImpl();
956
  /// Finish emission of machine code.
957
  void Finish();
958
959
5
  virtual bool mayHaveInstructions(MCSection &Sec) const { return true; }
960
};
961
962
/// Create a dummy machine code streamer, which does nothing. This is useful for
963
/// timing the assembler front end.
964
MCStreamer *createNullStreamer(MCContext &Ctx);
965
966
/// Create a machine code streamer which will print out assembly for the native
967
/// target, suitable for compiling with a native assembler.
968
///
969
/// \param InstPrint - If given, the instruction printer to use. If not given
970
/// the MCInst representation will be printed.  This method takes ownership of
971
/// InstPrint.
972
///
973
/// \param CE - If given, a code emitter to use to show the instruction
974
/// encoding inline with the assembly. This method takes ownership of \p CE.
975
///
976
/// \param TAB - If given, a target asm backend to use to show the fixup
977
/// information in conjunction with encoding information. This method takes
978
/// ownership of \p TAB.
979
///
980
/// \param ShowInst - Whether to show the MCInst representation inline with
981
/// the assembly.
982
MCStreamer *createAsmStreamer(MCContext &Ctx,
983
                              std::unique_ptr<formatted_raw_ostream> OS,
984
                              bool isVerboseAsm, bool useDwarfDirectory,
985
                              MCInstPrinter *InstPrint, MCCodeEmitter *CE,
986
                              MCAsmBackend *TAB, bool ShowInst);
987
988
} // end namespace llvm
989
990
#endif // LLVM_MC_MCSTREAMER_H