Coverage Report

Created: 2019-04-21 11:35

/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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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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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/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 "llvm/Support/VersionTuple.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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37
namespace llvm {
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39
class AssemblerConstantPools;
40
class formatted_raw_ostream;
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class MCAsmBackend;
42
class MCCodeEmitter;
43
struct MCCodePaddingContext;
44
class MCContext;
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struct MCDwarfFrameInfo;
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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;
51
class MCSymbolRefExpr;
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class MCSubtargetInfo;
53
class raw_ostream;
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class Twine;
55
56
using MCSectionSubPair = std::pair<MCSection *, const MCExpr *>;
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58
/// Target specific streamer interface. This is used so that targets can
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/// 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
65
///
66
/// FooTargetStreamer should have a pure virtual method for each directive. For
67
/// example, for a ".bar symbol_name" directive, it should have
68
/// virtual emitBar(const MCSymbol &Symbol) = 0;
69
///
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/// The FooTargetAsmStreamer and FooTargetELFStreamer classes implement the
71
/// method. The assembly streamer just prints ".bar symbol_name". The object
72
/// streamer does whatever is needed to implement .bar in the object file.
73
///
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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:
76
///
77
/// 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
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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();
90
91
7.75k
  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.
96
  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);
100
101
  virtual void emitDwarfFileDirective(StringRef Directive);
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  /// Update streamer for a new active section.
104
  ///
105
  /// This is called by PopSection and SwitchSection, if the current
106
  /// section changes.
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  virtual void changeSection(const MCSection *CurSection, MCSection *Section,
108
                             const MCExpr *SubSection, raw_ostream &OS);
109
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  virtual void emitValue(const MCExpr *Value);
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  /// Emit the bytes in \p Data into the output.
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  ///
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  /// This is used to emit bytes in \p Data as sequence of .byte directives.
115
  virtual void emitRawBytes(StringRef Data);
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117
  virtual void finish();
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};
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// FIXME: declared here because it is used from
121
// 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);
132
  virtual void emitHandlerData();
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  virtual void emitSetFP(unsigned FpReg, unsigned SpReg,
134
                         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,
138
                           bool isVector);
139
  virtual void emitUnwindRaw(int64_t StackOffset,
140
                             const SmallVectorImpl<uint8_t> &Opcodes);
141
142
  virtual void switchVendor(StringRef Vendor);
143
  virtual void emitAttribute(unsigned Attribute, unsigned Value);
144
  virtual void emitTextAttribute(unsigned Attribute, StringRef String);
145
  virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
146
                                    StringRef StringValue = "");
147
  virtual void emitFPU(unsigned FPU);
148
  virtual void emitArch(ARM::ArchKind Arch);
149
  virtual void emitArchExtension(unsigned ArchExt);
150
  virtual void emitObjectArch(ARM::ArchKind Arch);
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  void emitTargetAttributes(const MCSubtargetInfo &STI);
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  virtual void finishAttributeSection();
153
  virtual void emitInst(uint32_t Inst, char Suffix = '\0');
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  virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
156
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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.
168
  const MCExpr *addConstantPoolEntry(const MCExpr *, SMLoc Loc);
169
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  /// Callback used to implemnt the .ltorg directive.
171
  /// Emit contents of constant pool for the current section.
172
  void emitCurrentConstantPool();
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private:
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  std::unique_ptr<AssemblerConstantPools> ConstantPools;
176
};
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/// Streaming machine code generation interface.
179
///
180
/// This interface is intended to provide a programatic interface that is very
181
/// 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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///
185
/// 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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///
188
class MCStreamer {
189
  MCContext &Context;
190
  std::unique_ptr<MCTargetStreamer> TargetStreamer;
191
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  std::vector<MCDwarfFrameInfo> DwarfFrameInfos;
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  MCDwarfFrameInfo *getCurrentDwarfFrameInfo();
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  /// Similar to DwarfFrameInfos, but for SEH unwind info. Chained frames may
196
  /// refer to each other, so use std::unique_ptr to provide pointer stability.
197
  std::vector<std::unique_ptr<WinEH::FrameInfo>> WinFrameInfos;
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199
  WinEH::FrameInfo *CurrentWinFrameInfo;
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  /// Tracks an index to represent the order a symbol was emitted in.
202
  /// Zero means we did not emit that symbol.
203
  DenseMap<const MCSymbol *, unsigned> SymbolOrdering;
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205
  /// This is stack of current and previous section values saved by
206
  /// PushSection.
207
  SmallVector<std::pair<MCSectionSubPair, MCSectionSubPair>, 4> SectionStack;
208
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  /// The next unique ID to use when creating a WinCFI-related section (.pdata
210
  /// 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
212
  /// requires.
213
  unsigned NextWinCFIID = 0;
214
215
  bool UseAssemblerInfoForParsing;
216
217
protected:
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  MCStreamer(MCContext &Ctx);
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  virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
221
  virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
222
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109
  WinEH::FrameInfo *getCurrentWinFrameInfo() {
224
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    return CurrentWinFrameInfo;
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109
  }
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  virtual void EmitWindowsUnwindTables();
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  virtual void EmitRawTextImpl(StringRef String);
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  /// Returns true if the the .cv_loc directive is in the right section.
232
  bool checkCVLocSection(unsigned FuncId, unsigned FileNo, SMLoc Loc);
233
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public:
235
  MCStreamer(const MCStreamer &) = delete;
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  MCStreamer &operator=(const MCStreamer &) = delete;
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  virtual ~MCStreamer();
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  void visitUsedExpr(const MCExpr &Expr);
240
  virtual void visitUsedSymbol(const MCSymbol &Sym);
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6.88k
  void setTargetStreamer(MCTargetStreamer *TS) {
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6.88k
    TargetStreamer.reset(TS);
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6.88k
  }
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  /// State management
247
  ///
248
  virtual void reset();
249
250
7.72M
  MCContext &getContext() const { return Context; }
251
252
93
  virtual MCAssembler *getAssemblerPtr() { return nullptr; }
253
254
5.11k
  void setUseAssemblerInfoForParsing(bool v) { UseAssemblerInfoForParsing = v; }
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386k
  bool getUseAssemblerInfoForParsing() { return UseAssemblerInfoForParsing; }
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4.41M
  MCTargetStreamer *getTargetStreamer() {
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4.41M
    return TargetStreamer.get();
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4.41M
  }
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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.
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  virtual MCSymbol *EmitCFILabel();
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  /// Retreive the current frame info if one is available and it is not yet
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  /// closed. Otherwise, issue an error and return null.
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  WinEH::FrameInfo *EnsureValidWinFrameInfo(SMLoc Loc);
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  unsigned getNumFrameInfos();
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  ArrayRef<MCDwarfFrameInfo> getDwarfFrameInfos() const;
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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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  }
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  void generateCompactUnwindEncodings(MCAsmBackend *MAB);
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  /// \name Assembly File Formatting.
282
  /// @{
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  /// Return true if this streamer supports verbose assembly and if it is
285
  /// enabled.
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8.74k
  virtual bool isVerboseAsm() const { return false; }
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  /// Return true if this asm streamer supports emitting unformatted text
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  /// to the .s file with EmitRawText.
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172k
  virtual bool hasRawTextSupport() const { return false; }
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  /// Is the integrated assembler required for this streamer to function
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  /// correctly?
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426
  virtual bool isIntegratedAssemblerRequired() const { return false; }
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  /// 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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  ///
303
  /// 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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144k
  virtual void AddComment(const Twine &T, bool EOL = true) {}
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  /// 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
313
  /// method.
314
  virtual raw_ostream &GetCommentOS();
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  /// Print T and prefix it with the comment string (normally #) and
317
  /// optionally a tab. This prints the comment immediately, not at the end of
318
  /// 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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  /// 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.
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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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202k
  virtual void AddBlankLine() {}
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  /// @}
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  /// \name Symbol & Section Management
335
  /// @{
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  /// Return the current section that the streamer is emitting code to.
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17.2M
  MCSectionSubPair getCurrentSection() const {
339
17.2M
    if (!SectionStack.empty())
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17.2M
      return SectionStack.back().first;
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18.4E
    return MCSectionSubPair();
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18.4E
  }
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17.2M
  MCSection *getCurrentSectionOnly() const { return getCurrentSection().first; }
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  /// Return the previous section that the streamer is emitting code to.
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2.69k
  MCSectionSubPair getPreviousSection() const {
347
2.69k
    if (!SectionStack.empty())
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2.69k
      return SectionStack.back().second;
349
0
    return MCSectionSubPair();
350
0
  }
351
352
  /// Returns an index to represent the order a symbol was emitted in.
353
  /// (zero if we did not emit that symbol)
354
0
  unsigned GetSymbolOrder(const MCSymbol *Sym) const {
355
0
    return SymbolOrdering.lookup(Sym);
356
0
  }
357
358
  /// Update streamer for a new active section.
359
  ///
360
  /// This is called by PopSection and SwitchSection, if the current
361
  /// section changes.
362
  virtual void ChangeSection(MCSection *, const MCExpr *);
363
364
  /// Save the current and previous section on the section stack.
365
1.72k
  void PushSection() {
366
1.72k
    SectionStack.push_back(
367
1.72k
        std::make_pair(getCurrentSection(), getPreviousSection()));
368
1.72k
  }
369
370
  /// Restore the current and previous section from the section stack.
371
  /// Calls ChangeSection as needed.
372
  ///
373
  /// Returns false if the stack was empty.
374
1.72k
  bool PopSection() {
375
1.72k
    if (SectionStack.size() <= 1)
376
0
      return false;
377
1.72k
    auto I = SectionStack.end();
378
1.72k
    --I;
379
1.72k
    MCSectionSubPair OldSection = I->first;
380
1.72k
    --I;
381
1.72k
    MCSectionSubPair NewSection = I->first;
382
1.72k
383
1.72k
    if (OldSection != NewSection)
384
1.68k
      ChangeSection(NewSection.first, NewSection.second);
385
1.72k
    SectionStack.pop_back();
386
1.72k
    return true;
387
1.72k
  }
388
389
0
  bool SubSection(const MCExpr *Subsection) {
390
0
    if (SectionStack.empty())
391
0
      return false;
392
0
393
0
    SwitchSection(SectionStack.back().first.first, Subsection);
394
0
    return true;
395
0
  }
396
397
  /// Set the current section where code is being emitted to \p Section.  This
398
  /// is required to update CurSection.
399
  ///
400
  /// This corresponds to assembler directives like .section, .text, etc.
401
  virtual void SwitchSection(MCSection *Section,
402
                             const MCExpr *Subsection = nullptr);
403
404
  /// Set the current section where code is being emitted to \p Section.
405
  /// This is required to update CurSection. This version does not call
406
  /// ChangeSection.
407
  void SwitchSectionNoChange(MCSection *Section,
408
76
                             const MCExpr *Subsection = nullptr) {
409
76
    assert(Section && "Cannot switch to a null section!");
410
76
    MCSectionSubPair curSection = SectionStack.back().first;
411
76
    SectionStack.back().second = curSection;
412
76
    if (MCSectionSubPair(Section, Subsection) != curSection)
413
59
      SectionStack.back().first = MCSectionSubPair(Section, Subsection);
414
76
  }
415
416
  /// Create the default sections and set the initial one.
417
  virtual void InitSections(bool NoExecStack);
418
419
  MCSymbol *endSection(MCSection *Section);
420
421
  /// Sets the symbol's section.
422
  ///
423
  /// Each emitted symbol will be tracked in the ordering table,
424
  /// so we can sort on them later.
425
  void AssignFragment(MCSymbol *Symbol, MCFragment *Fragment);
426
427
  /// Emit a label for \p Symbol into the current section.
428
  ///
429
  /// This corresponds to an assembler statement such as:
430
  ///   foo:
431
  ///
432
  /// \param Symbol - The symbol to emit. A given symbol should only be
433
  /// emitted as a label once, and symbols emitted as a label should never be
434
  /// used in an assignment.
435
  // FIXME: These emission are non-const because we mutate the symbol to
436
  // add the section we're emitting it to later.
437
  virtual void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc());
438
439
  virtual void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol);
440
441
  /// Note in the output the specified \p Flag.
442
  virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
443
444
  /// Emit the given list \p Options of strings as linker
445
  /// options into the output.
446
0
  virtual void EmitLinkerOptions(ArrayRef<std::string> Kind) {}
447
448
  /// Note in the output the specified region \p Kind.
449
12
  virtual void EmitDataRegion(MCDataRegionType Kind) {}
450
451
  /// Specify the Mach-O minimum deployment target version.
452
  virtual void EmitVersionMin(MCVersionMinType Type, unsigned Major,
453
                              unsigned Minor, unsigned Update,
454
0
                              VersionTuple SDKVersion) {}
455
456
  /// Emit/Specify Mach-O build version command.
457
  /// \p Platform should be one of MachO::PlatformType.
458
  virtual void EmitBuildVersion(unsigned Platform, unsigned Major,
459
                                unsigned Minor, unsigned Update,
460
0
                                VersionTuple SDKVersion) {}
461
462
  void EmitVersionForTarget(const Triple &Target,
463
                            const VersionTuple &SDKVersion);
464
465
  /// Note in the output that the specified \p Func is a Thumb mode
466
  /// function (ARM target only).
467
  virtual void EmitThumbFunc(MCSymbol *Func);
468
469
  /// Emit an assignment of \p Value to \p Symbol.
470
  ///
471
  /// This corresponds to an assembler statement such as:
472
  ///  symbol = value
473
  ///
474
  /// The assignment generates no code, but has the side effect of binding the
475
  /// value in the current context. For the assembly streamer, this prints the
476
  /// binding into the .s file.
477
  ///
478
  /// \param Symbol - The symbol being assigned to.
479
  /// \param Value - The value for the symbol.
480
  virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
481
482
  /// Emit an weak reference from \p Alias to \p Symbol.
483
  ///
484
  /// This corresponds to an assembler statement such as:
485
  ///  .weakref alias, symbol
486
  ///
487
  /// \param Alias - The alias that is being created.
488
  /// \param Symbol - The symbol being aliased.
489
  virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
490
491
  /// Add the given \p Attribute to \p Symbol.
492
  virtual bool EmitSymbolAttribute(MCSymbol *Symbol,
493
                                   MCSymbolAttr Attribute) = 0;
494
495
  /// Set the \p DescValue for the \p Symbol.
496
  ///
497
  /// \param Symbol - The symbol to have its n_desc field set.
498
  /// \param DescValue - The value to set into the n_desc field.
499
  virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
500
501
  /// Start emitting COFF symbol definition
502
  ///
503
  /// \param Symbol - The symbol to have its External & Type fields set.
504
  virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
505
506
  /// Emit the storage class of the symbol.
507
  ///
508
  /// \param StorageClass - The storage class the symbol should have.
509
  virtual void EmitCOFFSymbolStorageClass(int StorageClass);
510
511
  /// Emit the type of the symbol.
512
  ///
513
  /// \param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
514
  virtual void EmitCOFFSymbolType(int Type);
515
516
  /// Marks the end of the symbol definition.
517
  virtual void EndCOFFSymbolDef();
518
519
  virtual void EmitCOFFSafeSEH(MCSymbol const *Symbol);
520
521
  /// Emits the symbol table index of a Symbol into the current section.
522
  virtual void EmitCOFFSymbolIndex(MCSymbol const *Symbol);
523
524
  /// Emits a COFF section index.
525
  ///
526
  /// \param Symbol - Symbol the section number relocation should point to.
527
  virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
528
529
  /// Emits a COFF section relative relocation.
530
  ///
531
  /// \param Symbol - Symbol the section relative relocation should point to.
532
  virtual void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset);
533
534
  /// Emits a COFF image relative relocation.
535
  ///
536
  /// \param Symbol - Symbol the image relative relocation should point to.
537
  virtual void EmitCOFFImgRel32(MCSymbol const *Symbol, int64_t Offset);
538
539
  /// Emit an ELF .size directive.
540
  ///
541
  /// This corresponds to an assembler statement such as:
542
  ///  .size symbol, expression
543
  virtual void emitELFSize(MCSymbol *Symbol, const MCExpr *Value);
544
545
  /// Emit an ELF .symver directive.
546
  ///
547
  /// This corresponds to an assembler statement such as:
548
  ///  .symver _start, foo@@SOME_VERSION
549
  /// \param AliasName - The versioned alias (i.e. "foo@@SOME_VERSION")
550
  /// \param Aliasee - The aliased symbol (i.e. "_start")
551
  virtual void emitELFSymverDirective(StringRef AliasName,
552
                                      const MCSymbol *Aliasee);
553
554
  /// Emit a Linker Optimization Hint (LOH) directive.
555
  /// \param Args - Arguments of the LOH.
556
0
  virtual void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {}
557
558
  /// Emit a common symbol.
559
  ///
560
  /// \param Symbol - The common symbol to emit.
561
  /// \param Size - The size of the common symbol.
562
  /// \param ByteAlignment - The alignment of the symbol if
563
  /// non-zero. This must be a power of 2.
564
  virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
565
                                unsigned ByteAlignment) = 0;
566
567
  /// Emit a local common (.lcomm) symbol.
568
  ///
569
  /// \param Symbol - The common symbol to emit.
570
  /// \param Size - The size of the common symbol.
571
  /// \param ByteAlignment - The alignment of the common symbol in bytes.
572
  virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
573
                                     unsigned ByteAlignment);
574
575
  /// Emit the zerofill section and an optional symbol.
576
  ///
577
  /// \param Section - The zerofill section to create and or to put the symbol
578
  /// \param Symbol - The zerofill symbol to emit, if non-NULL.
579
  /// \param Size - The size of the zerofill symbol.
580
  /// \param ByteAlignment - The alignment of the zerofill symbol if
581
  /// non-zero. This must be a power of 2 on some targets.
582
  virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
583
                            uint64_t Size = 0, unsigned ByteAlignment = 0,
584
                            SMLoc Loc = SMLoc()) = 0;
585
586
  /// Emit a thread local bss (.tbss) symbol.
587
  ///
588
  /// \param Section - The thread local common section.
589
  /// \param Symbol - The thread local common symbol to emit.
590
  /// \param Size - The size of the symbol.
591
  /// \param ByteAlignment - The alignment of the thread local common symbol
592
  /// if non-zero.  This must be a power of 2 on some targets.
593
  virtual void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
594
                              uint64_t Size, unsigned ByteAlignment = 0);
595
596
  /// @}
597
  /// \name Generating Data
598
  /// @{
599
600
  /// Emit the bytes in \p Data into the output.
601
  ///
602
  /// This is used to implement assembler directives such as .byte, .ascii,
603
  /// etc.
604
  virtual void EmitBytes(StringRef Data);
605
606
  /// Functionally identical to EmitBytes. When emitting textual assembly, this
607
  /// method uses .byte directives instead of .ascii or .asciz for readability.
608
  virtual void EmitBinaryData(StringRef Data);
609
610
  /// Emit the expression \p Value into the output as a native
611
  /// integer of the given \p Size bytes.
612
  ///
613
  /// This is used to implement assembler directives such as .word, .quad,
614
  /// etc.
615
  ///
616
  /// \param Value - The value to emit.
617
  /// \param Size - The size of the integer (in bytes) to emit. This must
618
  /// match a native machine width.
619
  /// \param Loc - The location of the expression for error reporting.
620
  virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
621
                             SMLoc Loc = SMLoc());
622
623
  void EmitValue(const MCExpr *Value, unsigned Size, SMLoc Loc = SMLoc());
624
625
  /// Special case of EmitValue that avoids the client having
626
  /// to pass in a MCExpr for constant integers.
627
  virtual void EmitIntValue(uint64_t Value, unsigned Size);
628
629
  virtual void EmitULEB128Value(const MCExpr *Value);
630
631
  virtual void EmitSLEB128Value(const MCExpr *Value);
632
633
  /// Special case of EmitULEB128Value that avoids the client having to
634
  /// pass in a MCExpr for constant integers.
635
  void EmitULEB128IntValue(uint64_t Value, unsigned PadTo = 0);
636
637
  /// Special case of EmitSLEB128Value that avoids the client having to
638
  /// pass in a MCExpr for constant integers.
639
  void EmitSLEB128IntValue(int64_t Value);
640
641
  /// Special case of EmitValue that avoids the client having to pass in
642
  /// a MCExpr for MCSymbols.
643
  void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
644
                       bool IsSectionRelative = false);
645
646
  /// Emit the expression \p Value into the output as a dtprel
647
  /// (64-bit DTP relative) value.
648
  ///
649
  /// This is used to implement assembler directives such as .dtpreldword on
650
  /// targets that support them.
651
  virtual void EmitDTPRel64Value(const MCExpr *Value);
652
653
  /// Emit the expression \p Value into the output as a dtprel
654
  /// (32-bit DTP relative) value.
655
  ///
656
  /// This is used to implement assembler directives such as .dtprelword on
657
  /// targets that support them.
658
  virtual void EmitDTPRel32Value(const MCExpr *Value);
659
660
  /// Emit the expression \p Value into the output as a tprel
661
  /// (64-bit TP relative) value.
662
  ///
663
  /// This is used to implement assembler directives such as .tpreldword on
664
  /// targets that support them.
665
  virtual void EmitTPRel64Value(const MCExpr *Value);
666
667
  /// Emit the expression \p Value into the output as a tprel
668
  /// (32-bit TP relative) value.
669
  ///
670
  /// This is used to implement assembler directives such as .tprelword on
671
  /// targets that support them.
672
  virtual void EmitTPRel32Value(const MCExpr *Value);
673
674
  /// Emit the expression \p Value into the output as a gprel64 (64-bit
675
  /// GP relative) value.
676
  ///
677
  /// This is used to implement assembler directives such as .gpdword on
678
  /// targets that support them.
679
  virtual void EmitGPRel64Value(const MCExpr *Value);
680
681
  /// Emit the expression \p Value into the output as a gprel32 (32-bit
682
  /// GP relative) value.
683
  ///
684
  /// This is used to implement assembler directives such as .gprel32 on
685
  /// targets that support them.
686
  virtual void EmitGPRel32Value(const MCExpr *Value);
687
688
  /// Emit NumBytes bytes worth of the value specified by FillValue.
689
  /// This implements directives such as '.space'.
690
  void emitFill(uint64_t NumBytes, uint8_t FillValue);
691
692
  /// Emit \p Size bytes worth of the value specified by \p FillValue.
693
  ///
694
  /// This is used to implement assembler directives such as .space or .skip.
695
  ///
696
  /// \param NumBytes - The number of bytes to emit.
697
  /// \param FillValue - The value to use when filling bytes.
698
  /// \param Loc - The location of the expression for error reporting.
699
  virtual void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
700
                        SMLoc Loc = SMLoc());
701
702
  /// Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is
703
  /// taken from the lowest order 4 bytes of \p Expr expression.
704
  ///
705
  /// This is used to implement assembler directives such as .fill.
706
  ///
707
  /// \param NumValues - The number of copies of \p Size bytes to emit.
708
  /// \param Size - The size (in bytes) of each repeated value.
709
  /// \param Expr - The expression from which \p Size bytes are used.
710
  virtual void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
711
                        SMLoc Loc = SMLoc());
712
713
  /// Emit NumBytes worth of zeros.
714
  /// This function properly handles data in virtual sections.
715
  void EmitZeros(uint64_t NumBytes);
716
717
  /// Emit some number of copies of \p Value until the byte alignment \p
718
  /// ByteAlignment is reached.
719
  ///
720
  /// If the number of bytes need to emit for the alignment is not a multiple
721
  /// of \p ValueSize, then the contents of the emitted fill bytes is
722
  /// undefined.
723
  ///
724
  /// This used to implement the .align assembler directive.
725
  ///
726
  /// \param ByteAlignment - The alignment to reach. This must be a power of
727
  /// two on some targets.
728
  /// \param Value - The value to use when filling bytes.
729
  /// \param ValueSize - The size of the integer (in bytes) to emit for
730
  /// \p Value. This must match a native machine width.
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 EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
735
                                    unsigned ValueSize = 1,
736
                                    unsigned MaxBytesToEmit = 0);
737
738
  /// Emit nops until the byte alignment \p ByteAlignment is reached.
739
  ///
740
  /// This used to align code where the alignment bytes may be executed.  This
741
  /// can emit different bytes for different sizes to optimize execution.
742
  ///
743
  /// \param ByteAlignment - The alignment to reach. This must be a power of
744
  /// two on some targets.
745
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
746
  /// the alignment cannot be reached in this many bytes, no bytes are
747
  /// emitted.
748
  virtual void EmitCodeAlignment(unsigned ByteAlignment,
749
                                 unsigned MaxBytesToEmit = 0);
750
751
  /// Emit some number of copies of \p Value until the byte offset \p
752
  /// Offset is reached.
753
  ///
754
  /// This is used to implement assembler directives such as .org.
755
  ///
756
  /// \param Offset - The offset to reach. This may be an expression, but the
757
  /// expression must be associated with the current section.
758
  /// \param Value - The value to use when filling bytes.
759
  virtual void emitValueToOffset(const MCExpr *Offset, unsigned char Value,
760
                                 SMLoc Loc);
761
762
  virtual void
763
42.9k
  EmitCodePaddingBasicBlockStart(const MCCodePaddingContext &Context) {}
764
765
  virtual void
766
42.9k
  EmitCodePaddingBasicBlockEnd(const MCCodePaddingContext &Context) {}
767
768
  /// @}
769
770
  /// Switch to a new logical file.  This is used to implement the '.file
771
  /// "foo.c"' assembler directive.
772
  virtual void EmitFileDirective(StringRef Filename);
773
774
  /// Emit the "identifiers" directive.  This implements the
775
  /// '.ident "version foo"' assembler directive.
776
2
  virtual void EmitIdent(StringRef IdentString) {}
777
778
  /// Associate a filename with a specified logical file number.  This
779
  /// implements the DWARF2 '.file 4 "foo.c"' assembler directive.
780
  unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
781
                                  StringRef Filename,
782
                                  Optional<MD5::MD5Result> Checksum = None,
783
                                  Optional<StringRef> Source = None,
784
168k
                                  unsigned CUID = 0) {
785
168k
    return cantFail(
786
168k
        tryEmitDwarfFileDirective(FileNo, Directory, Filename, Checksum,
787
168k
                                  Source, CUID));
788
168k
  }
789
790
  /// Associate a filename with a specified logical file number.
791
  /// Also associate a directory, optional checksum, and optional source
792
  /// text with the logical file.  This implements the DWARF2
793
  /// '.file 4 "dir/foo.c"' assembler directive, and the DWARF5
794
  /// '.file 4 "dir/foo.c" md5 "..." source "..."' assembler directive.
795
  virtual Expected<unsigned> tryEmitDwarfFileDirective(
796
      unsigned FileNo, StringRef Directory, StringRef Filename,
797
      Optional<MD5::MD5Result> Checksum = None, Optional<StringRef> Source = None,
798
      unsigned CUID = 0);
799
800
  /// Specify the "root" file of the compilation, using the ".file 0" extension.
801
  virtual void emitDwarfFile0Directive(StringRef Directory, StringRef Filename,
802
                                       Optional<MD5::MD5Result> Checksum,
803
                                       Optional<StringRef> Source,
804
                                       unsigned CUID = 0);
805
806
  virtual void EmitCFIBKeyFrame();
807
808
  /// This implements the DWARF2 '.loc fileno lineno ...' assembler
809
  /// directive.
810
  virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
811
                                     unsigned Column, unsigned Flags,
812
                                     unsigned Isa, unsigned Discriminator,
813
                                     StringRef FileName);
814
815
  /// Associate a filename with a specified logical file number, and also
816
  /// specify that file's checksum information.  This implements the '.cv_file 4
817
  /// "foo.c"' assembler directive. Returns true on success.
818
  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename,
819
                                   ArrayRef<uint8_t> Checksum,
820
                                   unsigned ChecksumKind);
821
822
  /// Introduces a function id for use with .cv_loc.
823
  virtual bool EmitCVFuncIdDirective(unsigned FunctionId);
824
825
  /// Introduces an inline call site id for use with .cv_loc. Includes
826
  /// extra information for inline line table generation.
827
  virtual bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
828
                                           unsigned IAFile, unsigned IALine,
829
                                           unsigned IACol, SMLoc Loc);
830
831
  /// This implements the CodeView '.cv_loc' assembler directive.
832
  virtual void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
833
                                  unsigned Line, unsigned Column,
834
                                  bool PrologueEnd, bool IsStmt,
835
                                  StringRef FileName, SMLoc Loc);
836
837
  /// This implements the CodeView '.cv_linetable' assembler directive.
838
  virtual void EmitCVLinetableDirective(unsigned FunctionId,
839
                                        const MCSymbol *FnStart,
840
                                        const MCSymbol *FnEnd);
841
842
  /// This implements the CodeView '.cv_inline_linetable' assembler
843
  /// directive.
844
  virtual void EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
845
                                              unsigned SourceFileId,
846
                                              unsigned SourceLineNum,
847
                                              const MCSymbol *FnStartSym,
848
                                              const MCSymbol *FnEndSym);
849
850
  /// This implements the CodeView '.cv_def_range' assembler
851
  /// directive.
852
  virtual void EmitCVDefRangeDirective(
853
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
854
      StringRef FixedSizePortion);
855
856
  /// This implements the CodeView '.cv_stringtable' assembler directive.
857
1
  virtual void EmitCVStringTableDirective() {}
858
859
  /// This implements the CodeView '.cv_filechecksums' assembler directive.
860
1
  virtual void EmitCVFileChecksumsDirective() {}
861
862
  /// This implements the CodeView '.cv_filechecksumoffset' assembler
863
  /// directive.
864
0
  virtual void EmitCVFileChecksumOffsetDirective(unsigned FileNo) {}
865
866
  /// This implements the CodeView '.cv_fpo_data' assembler directive.
867
0
  virtual void EmitCVFPOData(const MCSymbol *ProcSym, SMLoc Loc = {}) {}
868
869
  /// Emit the absolute difference between two symbols.
870
  ///
871
  /// \pre Offset of \c Hi is greater than the offset \c Lo.
872
  virtual void emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
873
                                      unsigned Size);
874
875
  /// Emit the absolute difference between two symbols encoded with ULEB128.
876
  virtual void emitAbsoluteSymbolDiffAsULEB128(const MCSymbol *Hi,
877
                                               const MCSymbol *Lo);
878
879
  virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
880
  virtual void EmitCFISections(bool EH, bool Debug);
881
  void EmitCFIStartProc(bool IsSimple, SMLoc Loc = SMLoc());
882
  void EmitCFIEndProc();
883
  virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
884
  virtual void EmitCFIDefCfaOffset(int64_t Offset);
885
  virtual void EmitCFIDefCfaRegister(int64_t Register);
886
  virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
887
  virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
888
  virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
889
  virtual void EmitCFIRememberState();
890
  virtual void EmitCFIRestoreState();
891
  virtual void EmitCFISameValue(int64_t Register);
892
  virtual void EmitCFIRestore(int64_t Register);
893
  virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
894
  virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
895
  virtual void EmitCFIEscape(StringRef Values);
896
  virtual void EmitCFIReturnColumn(int64_t Register);
897
  virtual void EmitCFIGnuArgsSize(int64_t Size);
898
  virtual void EmitCFISignalFrame();
899
  virtual void EmitCFIUndefined(int64_t Register);
900
  virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
901
  virtual void EmitCFIWindowSave();
902
  virtual void EmitCFINegateRAState();
903
904
  virtual void EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc = SMLoc());
905
  virtual void EmitWinCFIEndProc(SMLoc Loc = SMLoc());
906
  /// This is used on platforms, such as Windows on ARM64, that require function
907
  /// or funclet sizes to be emitted in .xdata before the End marker is emitted
908
  /// for the frame.  We cannot use the End marker, as it is not set at the
909
  /// point of emitting .xdata, in order to indicate that the frame is active.
910
  virtual void EmitWinCFIFuncletOrFuncEnd(SMLoc Loc = SMLoc());
911
  virtual void EmitWinCFIStartChained(SMLoc Loc = SMLoc());
912
  virtual void EmitWinCFIEndChained(SMLoc Loc = SMLoc());
913
  virtual void EmitWinCFIPushReg(unsigned Register, SMLoc Loc = SMLoc());
914
  virtual void EmitWinCFISetFrame(unsigned Register, unsigned Offset,
915
                                  SMLoc Loc = SMLoc());
916
  virtual void EmitWinCFIAllocStack(unsigned Size, SMLoc Loc = SMLoc());
917
  virtual void EmitWinCFISaveReg(unsigned Register, unsigned Offset,
918
                                 SMLoc Loc = SMLoc());
919
  virtual void EmitWinCFISaveXMM(unsigned Register, unsigned Offset,
920
                                 SMLoc Loc = SMLoc());
921
  virtual void EmitWinCFIPushFrame(bool Code, SMLoc Loc = SMLoc());
922
  virtual void EmitWinCFIEndProlog(SMLoc Loc = SMLoc());
923
  virtual void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except,
924
                                SMLoc Loc = SMLoc());
925
  virtual void EmitWinEHHandlerData(SMLoc Loc = SMLoc());
926
927
  virtual void emitCGProfileEntry(const MCSymbolRefExpr *From,
928
                                  const MCSymbolRefExpr *To, uint64_t Count);
929
930
  /// Get the .pdata section used for the given section. Typically the given
931
  /// section is either the main .text section or some other COMDAT .text
932
  /// section, but it may be any section containing code.
933
  MCSection *getAssociatedPDataSection(const MCSection *TextSec);
934
935
  /// Get the .xdata section used for the given section.
936
  MCSection *getAssociatedXDataSection(const MCSection *TextSec);
937
938
  virtual void EmitSyntaxDirective();
939
940
  /// Emit a .reloc directive.
941
  /// Returns true if the relocation could not be emitted because Name is not
942
  /// known.
943
  virtual bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
944
                                  const MCExpr *Expr, SMLoc Loc,
945
0
                                  const MCSubtargetInfo &STI) {
946
0
    return true;
947
0
  }
948
949
0
  virtual void EmitAddrsig() {}
950
0
  virtual void EmitAddrsigSym(const MCSymbol *Sym) {}
951
952
  /// Emit the given \p Instruction into the current section.
953
  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI);
954
955
  /// Set the bundle alignment mode from now on in the section.
956
  /// The argument is the power of 2 to which the alignment is set. The
957
  /// value 0 means turn the bundle alignment off.
958
  virtual void EmitBundleAlignMode(unsigned AlignPow2);
959
960
  /// The following instructions are a bundle-locked group.
961
  ///
962
  /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
963
  ///                     the end of a bundle.
964
  virtual void EmitBundleLock(bool AlignToEnd);
965
966
  /// Ends a bundle-locked group.
967
  virtual void EmitBundleUnlock();
968
969
  /// If this file is backed by a assembly streamer, this dumps the
970
  /// specified string in the output .s file.  This capability is indicated by
971
  /// the hasRawTextSupport() predicate.  By default this aborts.
972
  void EmitRawText(const Twine &String);
973
974
  /// Streamer specific finalization.
975
  virtual void FinishImpl();
976
  /// Finish emission of machine code.
977
  void Finish();
978
979
8
  virtual bool mayHaveInstructions(MCSection &Sec) const { return true; }
980
};
981
982
/// Create a dummy machine code streamer, which does nothing. This is useful for
983
/// timing the assembler front end.
984
MCStreamer *createNullStreamer(MCContext &Ctx);
985
986
/// Create a machine code streamer which will print out assembly for the native
987
/// target, suitable for compiling with a native assembler.
988
///
989
/// \param InstPrint - If given, the instruction printer to use. If not given
990
/// the MCInst representation will be printed.  This method takes ownership of
991
/// InstPrint.
992
///
993
/// \param CE - If given, a code emitter to use to show the instruction
994
/// encoding inline with the assembly. This method takes ownership of \p CE.
995
///
996
/// \param TAB - If given, a target asm backend to use to show the fixup
997
/// information in conjunction with encoding information. This method takes
998
/// ownership of \p TAB.
999
///
1000
/// \param ShowInst - Whether to show the MCInst representation inline with
1001
/// the assembly.
1002
MCStreamer *createAsmStreamer(MCContext &Ctx,
1003
                              std::unique_ptr<formatted_raw_ostream> OS,
1004
                              bool isVerboseAsm, bool useDwarfDirectory,
1005
                              MCInstPrinter *InstPrint, MCCodeEmitter *CE,
1006
                              MCAsmBackend *TAB, bool ShowInst);
1007
1008
} // end namespace llvm
1009
1010
#endif // LLVM_MC_MCSTREAMER_H