Coverage Report

Created: 2019-01-21 03:01

/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/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"
29
#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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38
namespace llvm {
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40
class AssemblerConstantPools;
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class formatted_raw_ostream;
42
class MCAsmBackend;
43
class MCCodeEmitter;
44
struct MCCodePaddingContext;
45
class MCContext;
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class MCExpr;
47
class MCInst;
48
class MCInstPrinter;
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class MCSection;
50
class MCStreamer;
51
class MCSymbolRefExpr;
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class MCSubtargetInfo;
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class raw_ostream;
54
class Twine;
55
56
using MCSectionSubPair = std::pair<MCSection *, const MCExpr *>;
57
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
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
///
74
/// 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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///
77
/// MCTargetStreamer &TS = OutStreamer.getTargetStreamer();
78
/// FooTargetStreamer &ATS = static_cast<FooTargetStreamer &>(TS);
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///
80
/// The base classes FooTargetAsmStreamer and FooTargetELFStreamer should
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/// *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
15.1k
  MCStreamer &getStreamer() { return Streamer; }
92
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);
97
98
  virtual void prettyPrintAsm(MCInstPrinter &InstPrinter, raw_ostream &OS,
99
                              const MCInst &Inst, const MCSubtargetInfo &STI);
100
101
  virtual void emitDwarfFileDirective(StringRef Directive);
102
103
  /// Update streamer for a new active section.
104
  ///
105
  /// This is called by PopSection and SwitchSection, if the current
106
  /// section changes.
107
  virtual void changeSection(const MCSection *CurSection, MCSection *Section,
108
                             const MCExpr *SubSection, raw_ostream &OS);
109
110
  virtual void emitValue(const MCExpr *Value);
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112
  /// 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);
116
117
  virtual void finish();
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};
119
120
// FIXME: declared here because it is used from
121
// lib/CodeGen/AsmPrinter/ARMException.cpp.
122
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();
128
  virtual void emitFnEnd();
129
  virtual void emitCantUnwind();
130
  virtual void emitPersonality(const MCSymbol *Personality);
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  virtual void emitPersonalityIndex(unsigned Index);
132
  virtual void emitHandlerData();
133
  virtual void emitSetFP(unsigned FpReg, unsigned SpReg,
134
                         int64_t Offset = 0);
135
  virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
136
  virtual void emitPad(int64_t Offset);
137
  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);
151
  void emitTargetAttributes(const MCSubtargetInfo &STI);
152
  virtual void finishAttributeSection();
153
  virtual void emitInst(uint32_t Inst, char Suffix = '\0');
154
155
  virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
156
157
  virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value);
158
159
  void finish() override;
160
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  /// Reset any state between object emissions, i.e. the equivalent of
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  /// MCStreamer's reset method.
163
  virtual void reset();
164
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  /// Callback used to implement the ldr= pseudo.
166
  /// Add a new entry to the constant pool for the current section and return an
167
  /// MCExpr that can be used to refer to the constant pool location.
168
  const MCExpr *addConstantPoolEntry(const MCExpr *, SMLoc Loc);
169
170
  /// Callback used to implemnt the .ltorg directive.
171
  /// Emit contents of constant pool for the current section.
172
  void emitCurrentConstantPool();
173
174
private:
175
  std::unique_ptr<AssemblerConstantPools> ConstantPools;
176
};
177
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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
182
/// to emit bytes, handle directives, etc.  The implementation of this interface
183
/// retains state to know what the current section is etc.
184
///
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.
187
///
188
class MCStreamer {
189
  MCContext &Context;
190
  std::unique_ptr<MCTargetStreamer> TargetStreamer;
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192
  std::vector<MCDwarfFrameInfo> DwarfFrameInfos;
193
  MCDwarfFrameInfo *getCurrentDwarfFrameInfo();
194
195
  /// 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;
198
199
  WinEH::FrameInfo *CurrentWinFrameInfo;
200
201
  /// 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;
204
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
211
  /// code section to unwind info section, which MSVC's incremental linker
212
  /// requires.
213
  unsigned NextWinCFIID = 0;
214
215
  bool UseAssemblerInfoForParsing;
216
217
protected:
218
  MCStreamer(MCContext &Ctx);
219
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  virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
221
  virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
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670
  WinEH::FrameInfo *getCurrentWinFrameInfo() {
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670
    return CurrentWinFrameInfo;
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670
  }
226
227
  virtual void EmitWindowsUnwindTables();
228
229
  virtual void EmitRawTextImpl(StringRef String);
230
231
  /// 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;
236
  MCStreamer &operator=(const MCStreamer &) = delete;
237
  virtual ~MCStreamer();
238
239
  void visitUsedExpr(const MCExpr &Expr);
240
  virtual void visitUsedSymbol(const MCSymbol &Sym);
241
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28.5k
  void setTargetStreamer(MCTargetStreamer *TS) {
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28.5k
    TargetStreamer.reset(TS);
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28.5k
  }
245
246
  /// State management
247
  ///
248
  virtual void reset();
249
250
53.6M
  MCContext &getContext() const { return Context; }
251
252
939
  virtual MCAssembler *getAssemblerPtr() { return nullptr; }
253
254
18.6k
  void setUseAssemblerInfoForParsing(bool v) { UseAssemblerInfoForParsing = v; }
255
2.54M
  bool getUseAssemblerInfoForParsing() { return UseAssemblerInfoForParsing; }
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27.5M
  MCTargetStreamer *getTargetStreamer() {
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27.5M
    return TargetStreamer.get();
259
27.5M
  }
260
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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
266
  /// closed. Otherwise, issue an error and return null.
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  WinEH::FrameInfo *EnsureValidWinFrameInfo(SMLoc Loc);
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21.4k
  unsigned getNumFrameInfos() { return DwarfFrameInfos.size(); }
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7.57k
  ArrayRef<MCDwarfFrameInfo> getDwarfFrameInfos() const {
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7.57k
    return DwarfFrameInfos;
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7.57k
  }
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  bool hasUnfinishedDwarfFrameInfo();
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452
  unsigned getNumWinFrameInfos() { return WinFrameInfos.size(); }
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136
  ArrayRef<std::unique_ptr<WinEH::FrameInfo>> getWinFrameInfos() const {
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    return WinFrameInfos;
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  }
280
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  void generateCompactUnwindEncodings(MCAsmBackend *MAB);
282
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  /// \name Assembly File Formatting.
284
  /// @{
285
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  /// Return true if this streamer supports verbose assembly and if it is
287
  /// enabled.
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42.9k
  virtual bool isVerboseAsm() const { return false; }
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  /// Return true if this asm streamer supports emitting unformatted text
291
  /// to the .s file with EmitRawText.
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1.32M
  virtual bool hasRawTextSupport() const { return false; }
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294
  /// Is the integrated assembler required for this streamer to function
295
  /// correctly?
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1.88k
  virtual bool isIntegratedAssemblerRequired() const { return false; }
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  /// Add a textual comment.
299
  ///
300
  /// Typically for comments that can be emitted to the generated .s
301
  /// 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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  ///
305
  /// If the comment includes embedded \n's, they will each get the comment
306
  /// prefix as appropriate.  The added comment should not end with a \n.
307
  /// By default, each comment is terminated with an end of line, i.e. the
308
  /// EOL param is set to true by default. If one prefers not to end the
309
  /// comment with a new line then the EOL param should be passed
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  /// with a false value.
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926k
  virtual void AddComment(const Twine &T, bool EOL = true) {}
312
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  /// Return a raw_ostream that comments can be written to. Unlike
314
  /// AddComment, you are required to terminate comments with \n if you use this
315
  /// method.
316
  virtual raw_ostream &GetCommentOS();
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  /// Print T and prefix it with the comment string (normally #) and
319
  /// optionally a tab. This prints the comment immediately, not at the end of
320
  /// the current line. It is basically a safe version of EmitRawText: since it
321
  /// only prints comments, the object streamer ignores it instead of asserting.
322
  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.
329
  virtual void emitExplicitComments();
330
331
  /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
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961k
  virtual void AddBlankLine() {}
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  /// @}
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336
  /// \name Symbol & Section Management
337
  /// @{
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339
  /// Return the current section that the streamer is emitting code to.
340
120M
  MCSectionSubPair getCurrentSection() const {
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120M
    if (!SectionStack.empty())
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120M
      return SectionStack.back().first;
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18.4E
    return MCSectionSubPair();
344
18.4E
  }
345
120M
  MCSection *getCurrentSectionOnly() const { return getCurrentSection().first; }
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347
  /// Return the previous section that the streamer is emitting code to.
348
17.1k
  MCSectionSubPair getPreviousSection() const {
349
17.1k
    if (!SectionStack.empty())
350
17.1k
      return SectionStack.back().second;
351
0
    return MCSectionSubPair();
352
0
  }
353
354
  /// Returns an index to represent the order a symbol was emitted in.
355
  /// (zero if we did not emit that symbol)
356
14
  unsigned GetSymbolOrder(const MCSymbol *Sym) const {
357
14
    return SymbolOrdering.lookup(Sym);
358
14
  }
359
360
  /// Update streamer for a new active section.
361
  ///
362
  /// This is called by PopSection and SwitchSection, if the current
363
  /// section changes.
364
  virtual void ChangeSection(MCSection *, const MCExpr *);
365
366
  /// Save the current and previous section on the section stack.
367
10.0k
  void PushSection() {
368
10.0k
    SectionStack.push_back(
369
10.0k
        std::make_pair(getCurrentSection(), getPreviousSection()));
370
10.0k
  }
371
372
  /// Restore the current and previous section from the section stack.
373
  /// Calls ChangeSection as needed.
374
  ///
375
  /// Returns false if the stack was empty.
376
10.0k
  bool PopSection() {
377
10.0k
    if (SectionStack.size() <= 1)
378
0
      return false;
379
10.0k
    auto I = SectionStack.end();
380
10.0k
    --I;
381
10.0k
    MCSectionSubPair OldSection = I->first;
382
10.0k
    --I;
383
10.0k
    MCSectionSubPair NewSection = I->first;
384
10.0k
385
10.0k
    if (OldSection != NewSection)
386
9.75k
      ChangeSection(NewSection.first, NewSection.second);
387
10.0k
    SectionStack.pop_back();
388
10.0k
    return true;
389
10.0k
  }
390
391
4
  bool SubSection(const MCExpr *Subsection) {
392
4
    if (SectionStack.empty())
393
0
      return false;
394
4
395
4
    SwitchSection(SectionStack.back().first.first, Subsection);
396
4
    return true;
397
4
  }
398
399
  /// Set the current section where code is being emitted to \p Section.  This
400
  /// is required to update CurSection.
401
  ///
402
  /// This corresponds to assembler directives like .section, .text, etc.
403
  virtual void SwitchSection(MCSection *Section,
404
                             const MCExpr *Subsection = nullptr);
405
406
  /// Set the current section where code is being emitted to \p Section.
407
  /// This is required to update CurSection. This version does not call
408
  /// ChangeSection.
409
  void SwitchSectionNoChange(MCSection *Section,
410
550
                             const MCExpr *Subsection = nullptr) {
411
550
    assert(Section && "Cannot switch to a null section!");
412
550
    MCSectionSubPair curSection = SectionStack.back().first;
413
550
    SectionStack.back().second = curSection;
414
550
    if (MCSectionSubPair(Section, Subsection) != curSection)
415
465
      SectionStack.back().first = MCSectionSubPair(Section, Subsection);
416
550
  }
417
418
  /// Create the default sections and set the initial one.
419
  virtual void InitSections(bool NoExecStack);
420
421
  MCSymbol *endSection(MCSection *Section);
422
423
  /// Sets the symbol's section.
424
  ///
425
  /// Each emitted symbol will be tracked in the ordering table,
426
  /// so we can sort on them later.
427
  void AssignFragment(MCSymbol *Symbol, MCFragment *Fragment);
428
429
  /// Emit a label for \p Symbol into the current section.
430
  ///
431
  /// This corresponds to an assembler statement such as:
432
  ///   foo:
433
  ///
434
  /// \param Symbol - The symbol to emit. A given symbol should only be
435
  /// emitted as a label once, and symbols emitted as a label should never be
436
  /// used in an assignment.
437
  // FIXME: These emission are non-const because we mutate the symbol to
438
  // add the section we're emitting it to later.
439
  virtual void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc());
440
441
  virtual void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol);
442
443
  /// Note in the output the specified \p Flag.
444
  virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
445
446
  /// Emit the given list \p Options of strings as linker
447
  /// options into the output.
448
0
  virtual void EmitLinkerOptions(ArrayRef<std::string> Kind) {}
449
450
  /// Note in the output the specified region \p Kind.
451
136
  virtual void EmitDataRegion(MCDataRegionType Kind) {}
452
453
  /// Specify the Mach-O minimum deployment target version.
454
  virtual void EmitVersionMin(MCVersionMinType Type, unsigned Major,
455
                              unsigned Minor, unsigned Update,
456
2
                              VersionTuple SDKVersion) {}
457
458
  /// Emit/Specify Mach-O build version command.
459
  /// \p Platform should be one of MachO::PlatformType.
460
  virtual void EmitBuildVersion(unsigned Platform, unsigned Major,
461
                                unsigned Minor, unsigned Update,
462
0
                                VersionTuple SDKVersion) {}
463
464
  void EmitVersionForTarget(const Triple &Target,
465
                            const VersionTuple &SDKVersion);
466
467
  /// Note in the output that the specified \p Func is a Thumb mode
468
  /// function (ARM target only).
469
  virtual void EmitThumbFunc(MCSymbol *Func);
470
471
  /// Emit an assignment of \p Value to \p Symbol.
472
  ///
473
  /// This corresponds to an assembler statement such as:
474
  ///  symbol = value
475
  ///
476
  /// The assignment generates no code, but has the side effect of binding the
477
  /// value in the current context. For the assembly streamer, this prints the
478
  /// binding into the .s file.
479
  ///
480
  /// \param Symbol - The symbol being assigned to.
481
  /// \param Value - The value for the symbol.
482
  virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
483
484
  /// Emit an weak reference from \p Alias to \p Symbol.
485
  ///
486
  /// This corresponds to an assembler statement such as:
487
  ///  .weakref alias, symbol
488
  ///
489
  /// \param Alias - The alias that is being created.
490
  /// \param Symbol - The symbol being aliased.
491
  virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
492
493
  /// Add the given \p Attribute to \p Symbol.
494
  virtual bool EmitSymbolAttribute(MCSymbol *Symbol,
495
                                   MCSymbolAttr Attribute) = 0;
496
497
  /// Set the \p DescValue for the \p Symbol.
498
  ///
499
  /// \param Symbol - The symbol to have its n_desc field set.
500
  /// \param DescValue - The value to set into the n_desc field.
501
  virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
502
503
  /// Start emitting COFF symbol definition
504
  ///
505
  /// \param Symbol - The symbol to have its External & Type fields set.
506
  virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
507
508
  /// Emit the storage class of the symbol.
509
  ///
510
  /// \param StorageClass - The storage class the symbol should have.
511
  virtual void EmitCOFFSymbolStorageClass(int StorageClass);
512
513
  /// Emit the type of the symbol.
514
  ///
515
  /// \param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
516
  virtual void EmitCOFFSymbolType(int Type);
517
518
  /// Marks the end of the symbol definition.
519
  virtual void EndCOFFSymbolDef();
520
521
  virtual void EmitCOFFSafeSEH(MCSymbol const *Symbol);
522
523
  /// Emits the symbol table index of a Symbol into the current section.
524
  virtual void EmitCOFFSymbolIndex(MCSymbol const *Symbol);
525
526
  /// Emits a COFF section index.
527
  ///
528
  /// \param Symbol - Symbol the section number relocation should point to.
529
  virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
530
531
  /// Emits a COFF section relative relocation.
532
  ///
533
  /// \param Symbol - Symbol the section relative relocation should point to.
534
  virtual void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset);
535
536
  /// Emits a COFF image relative relocation.
537
  ///
538
  /// \param Symbol - Symbol the image relative relocation should point to.
539
  virtual void EmitCOFFImgRel32(MCSymbol const *Symbol, int64_t Offset);
540
541
  /// Emit an ELF .size directive.
542
  ///
543
  /// This corresponds to an assembler statement such as:
544
  ///  .size symbol, expression
545
  virtual void emitELFSize(MCSymbol *Symbol, const MCExpr *Value);
546
547
  /// Emit an ELF .symver directive.
548
  ///
549
  /// This corresponds to an assembler statement such as:
550
  ///  .symver _start, foo@@SOME_VERSION
551
  /// \param AliasName - The versioned alias (i.e. "foo@@SOME_VERSION")
552
  /// \param Aliasee - The aliased symbol (i.e. "_start")
553
  virtual void emitELFSymverDirective(StringRef AliasName,
554
                                      const MCSymbol *Aliasee);
555
556
  /// Emit a Linker Optimization Hint (LOH) directive.
557
  /// \param Args - Arguments of the LOH.
558
0
  virtual void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {}
559
560
  /// Emit a common symbol.
561
  ///
562
  /// \param Symbol - The common symbol to emit.
563
  /// \param Size - The size of the common symbol.
564
  /// \param ByteAlignment - The alignment of the symbol if
565
  /// non-zero. This must be a power of 2.
566
  virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
567
                                unsigned ByteAlignment) = 0;
568
569
  /// Emit a local common (.lcomm) symbol.
570
  ///
571
  /// \param Symbol - The common symbol to emit.
572
  /// \param Size - The size of the common symbol.
573
  /// \param ByteAlignment - The alignment of the common symbol in bytes.
574
  virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
575
                                     unsigned ByteAlignment);
576
577
  /// Emit the zerofill section and an optional symbol.
578
  ///
579
  /// \param Section - The zerofill section to create and or to put the symbol
580
  /// \param Symbol - The zerofill symbol to emit, if non-NULL.
581
  /// \param Size - The size of the zerofill symbol.
582
  /// \param ByteAlignment - The alignment of the zerofill symbol if
583
  /// non-zero. This must be a power of 2 on some targets.
584
  virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
585
                            uint64_t Size = 0, unsigned ByteAlignment = 0,
586
                            SMLoc Loc = SMLoc()) = 0;
587
588
  /// Emit a thread local bss (.tbss) symbol.
589
  ///
590
  /// \param Section - The thread local common section.
591
  /// \param Symbol - The thread local common symbol to emit.
592
  /// \param Size - The size of the symbol.
593
  /// \param ByteAlignment - The alignment of the thread local common symbol
594
  /// if non-zero.  This must be a power of 2 on some targets.
595
  virtual void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
596
                              uint64_t Size, unsigned ByteAlignment = 0);
597
598
  /// @}
599
  /// \name Generating Data
600
  /// @{
601
602
  /// Emit the bytes in \p Data into the output.
603
  ///
604
  /// This is used to implement assembler directives such as .byte, .ascii,
605
  /// etc.
606
  virtual void EmitBytes(StringRef Data);
607
608
  /// Functionally identical to EmitBytes. When emitting textual assembly, this
609
  /// method uses .byte directives instead of .ascii or .asciz for readability.
610
  virtual void EmitBinaryData(StringRef Data);
611
612
  /// Emit the expression \p Value into the output as a native
613
  /// integer of the given \p Size bytes.
614
  ///
615
  /// This is used to implement assembler directives such as .word, .quad,
616
  /// etc.
617
  ///
618
  /// \param Value - The value to emit.
619
  /// \param Size - The size of the integer (in bytes) to emit. This must
620
  /// match a native machine width.
621
  /// \param Loc - The location of the expression for error reporting.
622
  virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
623
                             SMLoc Loc = SMLoc());
624
625
  void EmitValue(const MCExpr *Value, unsigned Size, SMLoc Loc = SMLoc());
626
627
  /// Special case of EmitValue that avoids the client having
628
  /// to pass in a MCExpr for constant integers.
629
  virtual void EmitIntValue(uint64_t Value, unsigned Size);
630
631
  virtual void EmitULEB128Value(const MCExpr *Value);
632
633
  virtual void EmitSLEB128Value(const MCExpr *Value);
634
635
  /// Special case of EmitULEB128Value that avoids the client having to
636
  /// pass in a MCExpr for constant integers.
637
  void EmitULEB128IntValue(uint64_t Value);
638
639
  /// Special case of EmitSLEB128Value that avoids the client having to
640
  /// pass in a MCExpr for constant integers.
641
  void EmitSLEB128IntValue(int64_t Value);
642
643
  /// Special case of EmitValue that avoids the client having to pass in
644
  /// a MCExpr for MCSymbols.
645
  void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
646
                       bool IsSectionRelative = false);
647
648
  /// Emit the expression \p Value into the output as a dtprel
649
  /// (64-bit DTP relative) value.
650
  ///
651
  /// This is used to implement assembler directives such as .dtpreldword on
652
  /// targets that support them.
653
  virtual void EmitDTPRel64Value(const MCExpr *Value);
654
655
  /// Emit the expression \p Value into the output as a dtprel
656
  /// (32-bit DTP relative) value.
657
  ///
658
  /// This is used to implement assembler directives such as .dtprelword on
659
  /// targets that support them.
660
  virtual void EmitDTPRel32Value(const MCExpr *Value);
661
662
  /// Emit the expression \p Value into the output as a tprel
663
  /// (64-bit TP relative) value.
664
  ///
665
  /// This is used to implement assembler directives such as .tpreldword on
666
  /// targets that support them.
667
  virtual void EmitTPRel64Value(const MCExpr *Value);
668
669
  /// Emit the expression \p Value into the output as a tprel
670
  /// (32-bit TP relative) value.
671
  ///
672
  /// This is used to implement assembler directives such as .tprelword on
673
  /// targets that support them.
674
  virtual void EmitTPRel32Value(const MCExpr *Value);
675
676
  /// Emit the expression \p Value into the output as a gprel64 (64-bit
677
  /// GP relative) value.
678
  ///
679
  /// This is used to implement assembler directives such as .gpdword on
680
  /// targets that support them.
681
  virtual void EmitGPRel64Value(const MCExpr *Value);
682
683
  /// Emit the expression \p Value into the output as a gprel32 (32-bit
684
  /// GP relative) value.
685
  ///
686
  /// This is used to implement assembler directives such as .gprel32 on
687
  /// targets that support them.
688
  virtual void EmitGPRel32Value(const MCExpr *Value);
689
690
  /// Emit NumBytes bytes worth of the value specified by FillValue.
691
  /// This implements directives such as '.space'.
692
  void emitFill(uint64_t NumBytes, uint8_t FillValue);
693
694
  /// Emit \p Size bytes worth of the value specified by \p FillValue.
695
  ///
696
  /// This is used to implement assembler directives such as .space or .skip.
697
  ///
698
  /// \param NumBytes - The number of bytes to emit.
699
  /// \param FillValue - The value to use when filling bytes.
700
  /// \param Loc - The location of the expression for error reporting.
701
  virtual void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
702
                        SMLoc Loc = SMLoc());
703
704
  /// Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is
705
  /// taken from the lowest order 4 bytes of \p Expr expression.
706
  ///
707
  /// This is used to implement assembler directives such as .fill.
708
  ///
709
  /// \param NumValues - The number of copies of \p Size bytes to emit.
710
  /// \param Size - The size (in bytes) of each repeated value.
711
  /// \param Expr - The expression from which \p Size bytes are used.
712
  virtual void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
713
                        SMLoc Loc = SMLoc());
714
715
  /// Emit NumBytes worth of zeros.
716
  /// This function properly handles data in virtual sections.
717
  void EmitZeros(uint64_t NumBytes);
718
719
  /// Emit some number of copies of \p Value until the byte alignment \p
720
  /// ByteAlignment is reached.
721
  ///
722
  /// If the number of bytes need to emit for the alignment is not a multiple
723
  /// of \p ValueSize, then the contents of the emitted fill bytes is
724
  /// undefined.
725
  ///
726
  /// This used to implement the .align assembler directive.
727
  ///
728
  /// \param ByteAlignment - The alignment to reach. This must be a power of
729
  /// two on some targets.
730
  /// \param Value - The value to use when filling bytes.
731
  /// \param ValueSize - The size of the integer (in bytes) to emit for
732
  /// \p Value. This must match a native machine width.
733
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
734
  /// the alignment cannot be reached in this many bytes, no bytes are
735
  /// emitted.
736
  virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
737
                                    unsigned ValueSize = 1,
738
                                    unsigned MaxBytesToEmit = 0);
739
740
  /// Emit nops until the byte alignment \p ByteAlignment is reached.
741
  ///
742
  /// This used to align code where the alignment bytes may be executed.  This
743
  /// can emit different bytes for different sizes to optimize execution.
744
  ///
745
  /// \param ByteAlignment - The alignment to reach. This must be a power of
746
  /// two on some targets.
747
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
748
  /// the alignment cannot be reached in this many bytes, no bytes are
749
  /// emitted.
750
  virtual void EmitCodeAlignment(unsigned ByteAlignment,
751
                                 unsigned MaxBytesToEmit = 0);
752
753
  /// Emit some number of copies of \p Value until the byte offset \p
754
  /// Offset is reached.
755
  ///
756
  /// This is used to implement assembler directives such as .org.
757
  ///
758
  /// \param Offset - The offset to reach. This may be an expression, but the
759
  /// expression must be associated with the current section.
760
  /// \param Value - The value to use when filling bytes.
761
  virtual void emitValueToOffset(const MCExpr *Offset, unsigned char Value,
762
                                 SMLoc Loc);
763
764
  virtual void
765
253k
  EmitCodePaddingBasicBlockStart(const MCCodePaddingContext &Context) {}
766
767
  virtual void
768
253k
  EmitCodePaddingBasicBlockEnd(const MCCodePaddingContext &Context) {}
769
770
  /// @}
771
772
  /// Switch to a new logical file.  This is used to implement the '.file
773
  /// "foo.c"' assembler directive.
774
  virtual void EmitFileDirective(StringRef Filename);
775
776
  /// Emit the "identifiers" directive.  This implements the
777
  /// '.ident "version foo"' assembler directive.
778
3
  virtual void EmitIdent(StringRef IdentString) {}
779
780
  /// Associate a filename with a specified logical file number.  This
781
  /// implements the DWARF2 '.file 4 "foo.c"' assembler directive.
782
  unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
783
                                  StringRef Filename,
784
                                  MD5::MD5Result *Checksum = nullptr,
785
                                  Optional<StringRef> Source = None,
786
1.29M
                                  unsigned CUID = 0) {
787
1.29M
    return cantFail(
788
1.29M
        tryEmitDwarfFileDirective(FileNo, Directory, Filename, Checksum,
789
1.29M
                                  Source, CUID));
790
1.29M
  }
791
792
  /// Associate a filename with a specified logical file number.
793
  /// Also associate a directory, optional checksum, and optional source
794
  /// text with the logical file.  This implements the DWARF2
795
  /// '.file 4 "dir/foo.c"' assembler directive, and the DWARF5
796
  /// '.file 4 "dir/foo.c" md5 "..." source "..."' assembler directive.
797
  virtual Expected<unsigned> tryEmitDwarfFileDirective(
798
      unsigned FileNo, StringRef Directory, StringRef Filename,
799
      MD5::MD5Result *Checksum = nullptr, Optional<StringRef> Source = None,
800
      unsigned CUID = 0);
801
802
  /// Specify the "root" file of the compilation, using the ".file 0" extension.
803
  virtual void emitDwarfFile0Directive(StringRef Directory, StringRef Filename,
804
                                       MD5::MD5Result *Checksum,
805
                                       Optional<StringRef> Source,
806
                                       unsigned CUID = 0);
807
808
  virtual void EmitCFIBKeyFrame();
809
810
  /// This implements the DWARF2 '.loc fileno lineno ...' assembler
811
  /// directive.
812
  virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
813
                                     unsigned Column, unsigned Flags,
814
                                     unsigned Isa, unsigned Discriminator,
815
                                     StringRef FileName);
816
817
  /// Associate a filename with a specified logical file number, and also
818
  /// specify that file's checksum information.  This implements the '.cv_file 4
819
  /// "foo.c"' assembler directive. Returns true on success.
820
  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename,
821
                                   ArrayRef<uint8_t> Checksum,
822
                                   unsigned ChecksumKind);
823
824
  /// Introduces a function id for use with .cv_loc.
825
  virtual bool EmitCVFuncIdDirective(unsigned FunctionId);
826
827
  /// Introduces an inline call site id for use with .cv_loc. Includes
828
  /// extra information for inline line table generation.
829
  virtual bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
830
                                           unsigned IAFile, unsigned IALine,
831
                                           unsigned IACol, SMLoc Loc);
832
833
  /// This implements the CodeView '.cv_loc' assembler directive.
834
  virtual void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
835
                                  unsigned Line, unsigned Column,
836
                                  bool PrologueEnd, bool IsStmt,
837
                                  StringRef FileName, SMLoc Loc);
838
839
  /// This implements the CodeView '.cv_linetable' assembler directive.
840
  virtual void EmitCVLinetableDirective(unsigned FunctionId,
841
                                        const MCSymbol *FnStart,
842
                                        const MCSymbol *FnEnd);
843
844
  /// This implements the CodeView '.cv_inline_linetable' assembler
845
  /// directive.
846
  virtual void EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
847
                                              unsigned SourceFileId,
848
                                              unsigned SourceLineNum,
849
                                              const MCSymbol *FnStartSym,
850
                                              const MCSymbol *FnEndSym);
851
852
  /// This implements the CodeView '.cv_def_range' assembler
853
  /// directive.
854
  virtual void EmitCVDefRangeDirective(
855
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
856
      StringRef FixedSizePortion);
857
858
  /// This implements the CodeView '.cv_stringtable' assembler directive.
859
1
  virtual void EmitCVStringTableDirective() {}
860
861
  /// This implements the CodeView '.cv_filechecksums' assembler directive.
862
1
  virtual void EmitCVFileChecksumsDirective() {}
863
864
  /// This implements the CodeView '.cv_filechecksumoffset' assembler
865
  /// directive.
866
0
  virtual void EmitCVFileChecksumOffsetDirective(unsigned FileNo) {}
867
868
  /// This implements the CodeView '.cv_fpo_data' assembler directive.
869
0
  virtual void EmitCVFPOData(const MCSymbol *ProcSym, SMLoc Loc = {}) {}
870
871
  /// Emit the absolute difference between two symbols.
872
  ///
873
  /// \pre Offset of \c Hi is greater than the offset \c Lo.
874
  virtual void emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
875
                                      unsigned Size);
876
877
  /// Emit the absolute difference between two symbols encoded with ULEB128.
878
  virtual void emitAbsoluteSymbolDiffAsULEB128(const MCSymbol *Hi,
879
                                               const MCSymbol *Lo);
880
881
  virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
882
  virtual void EmitCFISections(bool EH, bool Debug);
883
  void EmitCFIStartProc(bool IsSimple, SMLoc Loc = SMLoc());
884
  void EmitCFIEndProc();
885
  virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
886
  virtual void EmitCFIDefCfaOffset(int64_t Offset);
887
  virtual void EmitCFIDefCfaRegister(int64_t Register);
888
  virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
889
  virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
890
  virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
891
  virtual void EmitCFIRememberState();
892
  virtual void EmitCFIRestoreState();
893
  virtual void EmitCFISameValue(int64_t Register);
894
  virtual void EmitCFIRestore(int64_t Register);
895
  virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
896
  virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
897
  virtual void EmitCFIEscape(StringRef Values);
898
  virtual void EmitCFIReturnColumn(int64_t Register);
899
  virtual void EmitCFIGnuArgsSize(int64_t Size);
900
  virtual void EmitCFISignalFrame();
901
  virtual void EmitCFIUndefined(int64_t Register);
902
  virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
903
  virtual void EmitCFIWindowSave();
904
  virtual void EmitCFINegateRAState();
905
906
  virtual void EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc = SMLoc());
907
  virtual void EmitWinCFIEndProc(SMLoc Loc = SMLoc());
908
  /// This is used on platforms, such as Windows on ARM64, that require function
909
  /// or funclet sizes to be emitted in .xdata before the End marker is emitted
910
  /// for the frame.  We cannot use the End marker, as it is not set at the
911
  /// point of emitting .xdata, in order to indicate that the frame is active.
912
  virtual void EmitWinCFIFuncletOrFuncEnd(SMLoc Loc = SMLoc());
913
  virtual void EmitWinCFIStartChained(SMLoc Loc = SMLoc());
914
  virtual void EmitWinCFIEndChained(SMLoc Loc = SMLoc());
915
  virtual void EmitWinCFIPushReg(unsigned Register, SMLoc Loc = SMLoc());
916
  virtual void EmitWinCFISetFrame(unsigned Register, unsigned Offset,
917
                                  SMLoc Loc = SMLoc());
918
  virtual void EmitWinCFIAllocStack(unsigned Size, SMLoc Loc = SMLoc());
919
  virtual void EmitWinCFISaveReg(unsigned Register, unsigned Offset,
920
                                 SMLoc Loc = SMLoc());
921
  virtual void EmitWinCFISaveXMM(unsigned Register, unsigned Offset,
922
                                 SMLoc Loc = SMLoc());
923
  virtual void EmitWinCFIPushFrame(bool Code, SMLoc Loc = SMLoc());
924
  virtual void EmitWinCFIEndProlog(SMLoc Loc = SMLoc());
925
  virtual void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except,
926
                                SMLoc Loc = SMLoc());
927
  virtual void EmitWinEHHandlerData(SMLoc Loc = SMLoc());
928
929
  virtual void emitCGProfileEntry(const MCSymbolRefExpr *From,
930
                                  const MCSymbolRefExpr *To, uint64_t Count);
931
932
  /// Get the .pdata section used for the given section. Typically the given
933
  /// section is either the main .text section or some other COMDAT .text
934
  /// section, but it may be any section containing code.
935
  MCSection *getAssociatedPDataSection(const MCSection *TextSec);
936
937
  /// Get the .xdata section used for the given section.
938
  MCSection *getAssociatedXDataSection(const MCSection *TextSec);
939
940
  virtual void EmitSyntaxDirective();
941
942
  /// Emit a .reloc directive.
943
  /// Returns true if the relocation could not be emitted because Name is not
944
  /// known.
945
  virtual bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
946
                                  const MCExpr *Expr, SMLoc Loc,
947
0
                                  const MCSubtargetInfo &STI) {
948
0
    return true;
949
0
  }
950
951
0
  virtual void EmitAddrsig() {}
952
0
  virtual void EmitAddrsigSym(const MCSymbol *Sym) {}
953
954
  /// Emit the given \p Instruction into the current section.
955
  /// PrintSchedInfo == true then schedul comment should be added to output
956
  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
957
                               bool PrintSchedInfo = false);
958
959
  /// Set the bundle alignment mode from now on in the section.
960
  /// The argument is the power of 2 to which the alignment is set. The
961
  /// value 0 means turn the bundle alignment off.
962
  virtual void EmitBundleAlignMode(unsigned AlignPow2);
963
964
  /// The following instructions are a bundle-locked group.
965
  ///
966
  /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
967
  ///                     the end of a bundle.
968
  virtual void EmitBundleLock(bool AlignToEnd);
969
970
  /// Ends a bundle-locked group.
971
  virtual void EmitBundleUnlock();
972
973
  /// If this file is backed by a assembly streamer, this dumps the
974
  /// specified string in the output .s file.  This capability is indicated by
975
  /// the hasRawTextSupport() predicate.  By default this aborts.
976
  void EmitRawText(const Twine &String);
977
978
  /// Streamer specific finalization.
979
  virtual void FinishImpl();
980
  /// Finish emission of machine code.
981
  void Finish();
982
983
6
  virtual bool mayHaveInstructions(MCSection &Sec) const { return true; }
984
};
985
986
/// Create a dummy machine code streamer, which does nothing. This is useful for
987
/// timing the assembler front end.
988
MCStreamer *createNullStreamer(MCContext &Ctx);
989
990
/// Create a machine code streamer which will print out assembly for the native
991
/// target, suitable for compiling with a native assembler.
992
///
993
/// \param InstPrint - If given, the instruction printer to use. If not given
994
/// the MCInst representation will be printed.  This method takes ownership of
995
/// InstPrint.
996
///
997
/// \param CE - If given, a code emitter to use to show the instruction
998
/// encoding inline with the assembly. This method takes ownership of \p CE.
999
///
1000
/// \param TAB - If given, a target asm backend to use to show the fixup
1001
/// information in conjunction with encoding information. This method takes
1002
/// ownership of \p TAB.
1003
///
1004
/// \param ShowInst - Whether to show the MCInst representation inline with
1005
/// the assembly.
1006
MCStreamer *createAsmStreamer(MCContext &Ctx,
1007
                              std::unique_ptr<formatted_raw_ostream> OS,
1008
                              bool isVerboseAsm, bool useDwarfDirectory,
1009
                              MCInstPrinter *InstPrint, MCCodeEmitter *CE,
1010
                              MCAsmBackend *TAB, bool ShowInst);
1011
1012
} // end namespace llvm
1013
1014
#endif // LLVM_MC_MCSTREAMER_H