Coverage Report

Created: 2019-07-24 05:18

/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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13
#ifndef LLVM_MC_MCSTREAMER_H
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#define LLVM_MC_MCSTREAMER_H
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16
#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/DenseMap.h"
18
#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"
23
#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"
27
#include "llvm/Support/SMLoc.h"
28
#include "llvm/Support/TargetParser.h"
29
#include "llvm/Support/VersionTuple.h"
30
#include <cassert>
31
#include <cstdint>
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#include <memory>
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#include <string>
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#include <utility>
35
#include <vector>
36
37
namespace llvm {
38
39
class AssemblerConstantPools;
40
class formatted_raw_ostream;
41
class MCAsmBackend;
42
class MCCodeEmitter;
43
struct MCCodePaddingContext;
44
class MCContext;
45
struct MCDwarfFrameInfo;
46
class MCExpr;
47
class MCInst;
48
class MCInstPrinter;
49
class MCSection;
50
class MCStreamer;
51
class MCSymbolRefExpr;
52
class MCSubtargetInfo;
53
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
///
70
/// 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:
76
///
77
/// MCTargetStreamer &TS = OutStreamer.getTargetStreamer();
78
/// FooTargetStreamer &ATS = static_cast<FooTargetStreamer &>(TS);
79
///
80
/// The base classes FooTargetAsmStreamer and FooTargetELFStreamer should
81
/// *never* be treated differently. Callers should always talk to a
82
/// FooTargetStreamer.
83
class MCTargetStreamer {
84
protected:
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  MCStreamer &Streamer;
86
87
public:
88
  MCTargetStreamer(MCStreamer &S);
89
  virtual ~MCTargetStreamer();
90
91
16.9k
  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);
111
112
  /// Emit the bytes in \p Data into the output.
113
  ///
114
  /// 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();
118
};
119
120
// FIXME: declared here because it is used from
121
// lib/CodeGen/AsmPrinter/ARMException.cpp.
122
class ARMTargetStreamer : public MCTargetStreamer {
123
public:
124
  ARMTargetStreamer(MCStreamer &S);
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  ~ARMTargetStreamer() override;
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127
  virtual void emitFnStart();
128
  virtual void emitFnEnd();
129
  virtual void emitCantUnwind();
130
  virtual void emitPersonality(const MCSymbol *Personality);
131
  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');
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  virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
156
157
  virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value);
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159
  void finish() override;
160
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  /// Reset any state between object emissions, i.e. the equivalent of
162
  /// MCStreamer's reset method.
163
  virtual void reset();
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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
186
/// 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;
191
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
209
  /// 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
220
  virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
221
  virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
222
223
893
  WinEH::FrameInfo *getCurrentWinFrameInfo() {
224
893
    return CurrentWinFrameInfo;
225
893
  }
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  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
234
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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32.2k
  void setTargetStreamer(MCTargetStreamer *TS) {
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32.2k
    TargetStreamer.reset(TS);
244
32.2k
  }
245
246
  /// State management
247
  ///
248
  virtual void reset();
249
250
55.9M
  MCContext &getContext() const { return Context; }
251
252
1.01k
  virtual MCAssembler *getAssemblerPtr() { return nullptr; }
253
254
18.2k
  void setUseAssemblerInfoForParsing(bool v) { UseAssemblerInfoForParsing = v; }
255
2.48M
  bool getUseAssemblerInfoForParsing() { return UseAssemblerInfoForParsing; }
256
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28.6M
  MCTargetStreamer *getTargetStreamer() {
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28.6M
    return TargetStreamer.get();
259
28.6M
  }
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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.
267
  WinEH::FrameInfo *EnsureValidWinFrameInfo(SMLoc Loc);
268
269
  unsigned getNumFrameInfos();
270
  ArrayRef<MCDwarfFrameInfo> getDwarfFrameInfos() const;
271
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  bool hasUnfinishedDwarfFrameInfo();
273
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556
  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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182
  }
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  void generateCompactUnwindEncodings(MCAsmBackend *MAB);
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  /// \name Assembly File Formatting.
282
  /// @{
283
284
  /// Return true if this streamer supports verbose assembly and if it is
285
  /// enabled.
286
48.3k
  virtual bool isVerboseAsm() const { return false; }
287
288
  /// Return true if this asm streamer supports emitting unformatted text
289
  /// to the .s file with EmitRawText.
290
1.28M
  virtual bool hasRawTextSupport() const { return false; }
291
292
  /// Is the integrated assembler required for this streamer to function
293
  /// correctly?
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2.15k
  virtual bool isIntegratedAssemblerRequired() const { return false; }
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296
  /// Add a textual comment.
297
  ///
298
  /// Typically for comments that can be emitted to the generated .s
299
  /// file if applicable as a QoI issue to make the output of the compiler
300
  /// more readable.  This only affects the MCAsmStreamer, and only when
301
  /// verbose assembly output is enabled.
302
  ///
303
  /// If the comment includes embedded \n's, they will each get the comment
304
  /// prefix as appropriate.  The added comment should not end with a \n.
305
  /// By default, each comment is terminated with an end of line, i.e. the
306
  /// EOL param is set to true by default. If one prefers not to end the
307
  /// comment with a new line then the EOL param should be passed
308
  /// with a false value.
309
965k
  virtual void AddComment(const Twine &T, bool EOL = true) {}
310
311
  /// Return a raw_ostream that comments can be written to. Unlike
312
  /// AddComment, you are required to terminate comments with \n if you use this
313
  /// method.
314
  virtual raw_ostream &GetCommentOS();
315
316
  /// 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
319
  /// only prints comments, the object streamer ignores it instead of asserting.
320
  virtual void emitRawComment(const Twine &T, bool TabPrefix = true);
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  /// Add explicit comment T. T is required to be a valid
323
  /// comment in the output and does not need to be escaped.
324
  virtual void addExplicitComment(const Twine &T);
325
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  /// Emit added explicit comments.
327
  virtual void emitExplicitComments();
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  /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
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985k
  virtual void AddBlankLine() {}
331
332
  /// @}
333
334
  /// \name Symbol & Section Management
335
  /// @{
336
337
  /// Return the current section that the streamer is emitting code to.
338
124M
  MCSectionSubPair getCurrentSection() const {
339
124M
    if (!SectionStack.empty())
340
124M
      return SectionStack.back().first;
341
18.4E
    return MCSectionSubPair();
342
18.4E
  }
343
124M
  MCSection *getCurrentSectionOnly() const { return getCurrentSection().first; }
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345
  /// Return the previous section that the streamer is emitting code to.
346
19.3k
  MCSectionSubPair getPreviousSection() const {
347
19.3k
    if (!SectionStack.empty())
348
19.3k
      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
14
  unsigned GetSymbolOrder(const MCSymbol *Sym) const {
355
14
    return SymbolOrdering.lookup(Sym);
356
14
  }
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
11.6k
  void PushSection() {
366
11.6k
    SectionStack.push_back(
367
11.6k
        std::make_pair(getCurrentSection(), getPreviousSection()));
368
11.6k
  }
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
11.6k
  bool PopSection() {
375
11.6k
    if (SectionStack.size() <= 1)
376
0
      return false;
377
11.6k
    auto I = SectionStack.end();
378
11.6k
    --I;
379
11.6k
    MCSectionSubPair OldSection = I->first;
380
11.6k
    --I;
381
11.6k
    MCSectionSubPair NewSection = I->first;
382
11.6k
383
11.6k
    if (OldSection != NewSection)
384
11.3k
      ChangeSection(NewSection.first, NewSection.second);
385
11.6k
    SectionStack.pop_back();
386
11.6k
    return true;
387
11.6k
  }
388
389
4
  bool SubSection(const MCExpr *Subsection) {
390
4
    if (SectionStack.empty())
391
0
      return false;
392
4
393
4
    SwitchSection(SectionStack.back().first.first, Subsection);
394
4
    return true;
395
4
  }
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
685
                             const MCExpr *Subsection = nullptr) {
409
685
    assert(Section && "Cannot switch to a null section!");
410
685
    MCSectionSubPair curSection = SectionStack.back().first;
411
685
    SectionStack.back().second = curSection;
412
685
    if (MCSectionSubPair(Section, Subsection) != curSection)
413
544
      SectionStack.back().first = MCSectionSubPair(Section, Subsection);
414
685
  }
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
136
  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
2
                              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
  /// Special case of EmitValue that avoids the client having to pass
630
  /// in a MCExpr for constant integers & prints in Hex format for certain
631
  /// modes.
632
25.4k
  virtual void EmitIntValueInHex(uint64_t Value, unsigned Size) {
633
25.4k
    EmitIntValue(Value, Size);
634
25.4k
  }
635
636
  virtual void EmitULEB128Value(const MCExpr *Value);
637
638
  virtual void EmitSLEB128Value(const MCExpr *Value);
639
640
  /// Special case of EmitULEB128Value that avoids the client having to
641
  /// pass in a MCExpr for constant integers.
642
  void EmitULEB128IntValue(uint64_t Value, unsigned PadTo = 0);
643
644
  /// Special case of EmitSLEB128Value that avoids the client having to
645
  /// pass in a MCExpr for constant integers.
646
  void EmitSLEB128IntValue(int64_t Value);
647
648
  /// Special case of EmitValue that avoids the client having to pass in
649
  /// a MCExpr for MCSymbols.
650
  void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
651
                       bool IsSectionRelative = false);
652
653
  /// Emit the expression \p Value into the output as a dtprel
654
  /// (64-bit DTP relative) value.
655
  ///
656
  /// This is used to implement assembler directives such as .dtpreldword on
657
  /// targets that support them.
658
  virtual void EmitDTPRel64Value(const MCExpr *Value);
659
660
  /// Emit the expression \p Value into the output as a dtprel
661
  /// (32-bit DTP relative) value.
662
  ///
663
  /// This is used to implement assembler directives such as .dtprelword on
664
  /// targets that support them.
665
  virtual void EmitDTPRel32Value(const MCExpr *Value);
666
667
  /// Emit the expression \p Value into the output as a tprel
668
  /// (64-bit TP relative) value.
669
  ///
670
  /// This is used to implement assembler directives such as .tpreldword on
671
  /// targets that support them.
672
  virtual void EmitTPRel64Value(const MCExpr *Value);
673
674
  /// Emit the expression \p Value into the output as a tprel
675
  /// (32-bit TP relative) value.
676
  ///
677
  /// This is used to implement assembler directives such as .tprelword on
678
  /// targets that support them.
679
  virtual void EmitTPRel32Value(const MCExpr *Value);
680
681
  /// Emit the expression \p Value into the output as a gprel64 (64-bit
682
  /// GP relative) value.
683
  ///
684
  /// This is used to implement assembler directives such as .gpdword on
685
  /// targets that support them.
686
  virtual void EmitGPRel64Value(const MCExpr *Value);
687
688
  /// Emit the expression \p Value into the output as a gprel32 (32-bit
689
  /// GP relative) value.
690
  ///
691
  /// This is used to implement assembler directives such as .gprel32 on
692
  /// targets that support them.
693
  virtual void EmitGPRel32Value(const MCExpr *Value);
694
695
  /// Emit NumBytes bytes worth of the value specified by FillValue.
696
  /// This implements directives such as '.space'.
697
  void emitFill(uint64_t NumBytes, uint8_t FillValue);
698
699
  /// Emit \p Size bytes worth of the value specified by \p FillValue.
700
  ///
701
  /// This is used to implement assembler directives such as .space or .skip.
702
  ///
703
  /// \param NumBytes - The number of bytes to emit.
704
  /// \param FillValue - The value to use when filling bytes.
705
  /// \param Loc - The location of the expression for error reporting.
706
  virtual void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
707
                        SMLoc Loc = SMLoc());
708
709
  /// Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is
710
  /// taken from the lowest order 4 bytes of \p Expr expression.
711
  ///
712
  /// This is used to implement assembler directives such as .fill.
713
  ///
714
  /// \param NumValues - The number of copies of \p Size bytes to emit.
715
  /// \param Size - The size (in bytes) of each repeated value.
716
  /// \param Expr - The expression from which \p Size bytes are used.
717
  virtual void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
718
                        SMLoc Loc = SMLoc());
719
720
  /// Emit NumBytes worth of zeros.
721
  /// This function properly handles data in virtual sections.
722
  void EmitZeros(uint64_t NumBytes);
723
724
  /// Emit some number of copies of \p Value until the byte alignment \p
725
  /// ByteAlignment is reached.
726
  ///
727
  /// If the number of bytes need to emit for the alignment is not a multiple
728
  /// of \p ValueSize, then the contents of the emitted fill bytes is
729
  /// undefined.
730
  ///
731
  /// This used to implement the .align assembler directive.
732
  ///
733
  /// \param ByteAlignment - The alignment to reach. This must be a power of
734
  /// two on some targets.
735
  /// \param Value - The value to use when filling bytes.
736
  /// \param ValueSize - The size of the integer (in bytes) to emit for
737
  /// \p Value. This must match a native machine width.
738
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
739
  /// the alignment cannot be reached in this many bytes, no bytes are
740
  /// emitted.
741
  virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
742
                                    unsigned ValueSize = 1,
743
                                    unsigned MaxBytesToEmit = 0);
744
745
  /// Emit nops until the byte alignment \p ByteAlignment is reached.
746
  ///
747
  /// This used to align code where the alignment bytes may be executed.  This
748
  /// can emit different bytes for different sizes to optimize execution.
749
  ///
750
  /// \param ByteAlignment - The alignment to reach. This must be a power of
751
  /// two on some targets.
752
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
753
  /// the alignment cannot be reached in this many bytes, no bytes are
754
  /// emitted.
755
  virtual void EmitCodeAlignment(unsigned ByteAlignment,
756
                                 unsigned MaxBytesToEmit = 0);
757
758
  /// Emit some number of copies of \p Value until the byte offset \p
759
  /// Offset is reached.
760
  ///
761
  /// This is used to implement assembler directives such as .org.
762
  ///
763
  /// \param Offset - The offset to reach. This may be an expression, but the
764
  /// expression must be associated with the current section.
765
  /// \param Value - The value to use when filling bytes.
766
  virtual void emitValueToOffset(const MCExpr *Offset, unsigned char Value,
767
                                 SMLoc Loc);
768
769
  virtual void
770
278k
  EmitCodePaddingBasicBlockStart(const MCCodePaddingContext &Context) {}
771
772
  virtual void
773
278k
  EmitCodePaddingBasicBlockEnd(const MCCodePaddingContext &Context) {}
774
775
  /// @}
776
777
  /// Switch to a new logical file.  This is used to implement the '.file
778
  /// "foo.c"' assembler directive.
779
  virtual void EmitFileDirective(StringRef Filename);
780
781
  /// Emit the "identifiers" directive.  This implements the
782
  /// '.ident "version foo"' assembler directive.
783
3
  virtual void EmitIdent(StringRef IdentString) {}
784
785
  /// Associate a filename with a specified logical file number.  This
786
  /// implements the DWARF2 '.file 4 "foo.c"' assembler directive.
787
  unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
788
                                  StringRef Filename,
789
                                  Optional<MD5::MD5Result> Checksum = None,
790
                                  Optional<StringRef> Source = None,
791
1.25M
                                  unsigned CUID = 0) {
792
1.25M
    return cantFail(
793
1.25M
        tryEmitDwarfFileDirective(FileNo, Directory, Filename, Checksum,
794
1.25M
                                  Source, CUID));
795
1.25M
  }
796
797
  /// Associate a filename with a specified logical file number.
798
  /// Also associate a directory, optional checksum, and optional source
799
  /// text with the logical file.  This implements the DWARF2
800
  /// '.file 4 "dir/foo.c"' assembler directive, and the DWARF5
801
  /// '.file 4 "dir/foo.c" md5 "..." source "..."' assembler directive.
802
  virtual Expected<unsigned> tryEmitDwarfFileDirective(
803
      unsigned FileNo, StringRef Directory, StringRef Filename,
804
      Optional<MD5::MD5Result> Checksum = None, Optional<StringRef> Source = None,
805
      unsigned CUID = 0);
806
807
  /// Specify the "root" file of the compilation, using the ".file 0" extension.
808
  virtual void emitDwarfFile0Directive(StringRef Directory, StringRef Filename,
809
                                       Optional<MD5::MD5Result> Checksum,
810
                                       Optional<StringRef> Source,
811
                                       unsigned CUID = 0);
812
813
  virtual void EmitCFIBKeyFrame();
814
815
  /// This implements the DWARF2 '.loc fileno lineno ...' assembler
816
  /// directive.
817
  virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
818
                                     unsigned Column, unsigned Flags,
819
                                     unsigned Isa, unsigned Discriminator,
820
                                     StringRef FileName);
821
822
  /// Associate a filename with a specified logical file number, and also
823
  /// specify that file's checksum information.  This implements the '.cv_file 4
824
  /// "foo.c"' assembler directive. Returns true on success.
825
  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename,
826
                                   ArrayRef<uint8_t> Checksum,
827
                                   unsigned ChecksumKind);
828
829
  /// Introduces a function id for use with .cv_loc.
830
  virtual bool EmitCVFuncIdDirective(unsigned FunctionId);
831
832
  /// Introduces an inline call site id for use with .cv_loc. Includes
833
  /// extra information for inline line table generation.
834
  virtual bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
835
                                           unsigned IAFile, unsigned IALine,
836
                                           unsigned IACol, SMLoc Loc);
837
838
  /// This implements the CodeView '.cv_loc' assembler directive.
839
  virtual void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
840
                                  unsigned Line, unsigned Column,
841
                                  bool PrologueEnd, bool IsStmt,
842
                                  StringRef FileName, SMLoc Loc);
843
844
  /// This implements the CodeView '.cv_linetable' assembler directive.
845
  virtual void EmitCVLinetableDirective(unsigned FunctionId,
846
                                        const MCSymbol *FnStart,
847
                                        const MCSymbol *FnEnd);
848
849
  /// This implements the CodeView '.cv_inline_linetable' assembler
850
  /// directive.
851
  virtual void EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
852
                                              unsigned SourceFileId,
853
                                              unsigned SourceLineNum,
854
                                              const MCSymbol *FnStartSym,
855
                                              const MCSymbol *FnEndSym);
856
857
  /// This implements the CodeView '.cv_def_range' assembler
858
  /// directive.
859
  virtual void EmitCVDefRangeDirective(
860
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
861
      StringRef FixedSizePortion);
862
863
  /// This implements the CodeView '.cv_stringtable' assembler directive.
864
1
  virtual void EmitCVStringTableDirective() {}
865
866
  /// This implements the CodeView '.cv_filechecksums' assembler directive.
867
1
  virtual void EmitCVFileChecksumsDirective() {}
868
869
  /// This implements the CodeView '.cv_filechecksumoffset' assembler
870
  /// directive.
871
0
  virtual void EmitCVFileChecksumOffsetDirective(unsigned FileNo) {}
872
873
  /// This implements the CodeView '.cv_fpo_data' assembler directive.
874
0
  virtual void EmitCVFPOData(const MCSymbol *ProcSym, SMLoc Loc = {}) {}
875
876
  /// Emit the absolute difference between two symbols.
877
  ///
878
  /// \pre Offset of \c Hi is greater than the offset \c Lo.
879
  virtual void emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
880
                                      unsigned Size);
881
882
  /// Emit the absolute difference between two symbols encoded with ULEB128.
883
  virtual void emitAbsoluteSymbolDiffAsULEB128(const MCSymbol *Hi,
884
                                               const MCSymbol *Lo);
885
886
  virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
887
  virtual void EmitCFISections(bool EH, bool Debug);
888
  void EmitCFIStartProc(bool IsSimple, SMLoc Loc = SMLoc());
889
  void EmitCFIEndProc();
890
  virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
891
  virtual void EmitCFIDefCfaOffset(int64_t Offset);
892
  virtual void EmitCFIDefCfaRegister(int64_t Register);
893
  virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
894
  virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
895
  virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
896
  virtual void EmitCFIRememberState();
897
  virtual void EmitCFIRestoreState();
898
  virtual void EmitCFISameValue(int64_t Register);
899
  virtual void EmitCFIRestore(int64_t Register);
900
  virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
901
  virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
902
  virtual void EmitCFIEscape(StringRef Values);
903
  virtual void EmitCFIReturnColumn(int64_t Register);
904
  virtual void EmitCFIGnuArgsSize(int64_t Size);
905
  virtual void EmitCFISignalFrame();
906
  virtual void EmitCFIUndefined(int64_t Register);
907
  virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
908
  virtual void EmitCFIWindowSave();
909
  virtual void EmitCFINegateRAState();
910
911
  virtual void EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc = SMLoc());
912
  virtual void EmitWinCFIEndProc(SMLoc Loc = SMLoc());
913
  /// This is used on platforms, such as Windows on ARM64, that require function
914
  /// or funclet sizes to be emitted in .xdata before the End marker is emitted
915
  /// for the frame.  We cannot use the End marker, as it is not set at the
916
  /// point of emitting .xdata, in order to indicate that the frame is active.
917
  virtual void EmitWinCFIFuncletOrFuncEnd(SMLoc Loc = SMLoc());
918
  virtual void EmitWinCFIStartChained(SMLoc Loc = SMLoc());
919
  virtual void EmitWinCFIEndChained(SMLoc Loc = SMLoc());
920
  virtual void EmitWinCFIPushReg(unsigned Register, SMLoc Loc = SMLoc());
921
  virtual void EmitWinCFISetFrame(unsigned Register, unsigned Offset,
922
                                  SMLoc Loc = SMLoc());
923
  virtual void EmitWinCFIAllocStack(unsigned Size, SMLoc Loc = SMLoc());
924
  virtual void EmitWinCFISaveReg(unsigned Register, unsigned Offset,
925
                                 SMLoc Loc = SMLoc());
926
  virtual void EmitWinCFISaveXMM(unsigned Register, unsigned Offset,
927
                                 SMLoc Loc = SMLoc());
928
  virtual void EmitWinCFIPushFrame(bool Code, SMLoc Loc = SMLoc());
929
  virtual void EmitWinCFIEndProlog(SMLoc Loc = SMLoc());
930
  virtual void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except,
931
                                SMLoc Loc = SMLoc());
932
  virtual void EmitWinEHHandlerData(SMLoc Loc = SMLoc());
933
934
  virtual void emitCGProfileEntry(const MCSymbolRefExpr *From,
935
                                  const MCSymbolRefExpr *To, uint64_t Count);
936
937
  /// Get the .pdata section used for the given section. Typically the given
938
  /// section is either the main .text section or some other COMDAT .text
939
  /// section, but it may be any section containing code.
940
  MCSection *getAssociatedPDataSection(const MCSection *TextSec);
941
942
  /// Get the .xdata section used for the given section.
943
  MCSection *getAssociatedXDataSection(const MCSection *TextSec);
944
945
  virtual void EmitSyntaxDirective();
946
947
  /// Emit a .reloc directive.
948
  /// Returns true if the relocation could not be emitted because Name is not
949
  /// known.
950
  virtual bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
951
                                  const MCExpr *Expr, SMLoc Loc,
952
0
                                  const MCSubtargetInfo &STI) {
953
0
    return true;
954
0
  }
955
956
0
  virtual void EmitAddrsig() {}
957
0
  virtual void EmitAddrsigSym(const MCSymbol *Sym) {}
958
959
  /// Emit the given \p Instruction into the current section.
960
  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI);
961
962
  /// Set the bundle alignment mode from now on in the section.
963
  /// The argument is the power of 2 to which the alignment is set. The
964
  /// value 0 means turn the bundle alignment off.
965
  virtual void EmitBundleAlignMode(unsigned AlignPow2);
966
967
  /// The following instructions are a bundle-locked group.
968
  ///
969
  /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
970
  ///                     the end of a bundle.
971
  virtual void EmitBundleLock(bool AlignToEnd);
972
973
  /// Ends a bundle-locked group.
974
  virtual void EmitBundleUnlock();
975
976
  /// If this file is backed by a assembly streamer, this dumps the
977
  /// specified string in the output .s file.  This capability is indicated by
978
  /// the hasRawTextSupport() predicate.  By default this aborts.
979
  void EmitRawText(const Twine &String);
980
981
  /// Streamer specific finalization.
982
  virtual void FinishImpl();
983
  /// Finish emission of machine code.
984
  void Finish();
985
986
10
  virtual bool mayHaveInstructions(MCSection &Sec) const { return true; }
987
};
988
989
/// Create a dummy machine code streamer, which does nothing. This is useful for
990
/// timing the assembler front end.
991
MCStreamer *createNullStreamer(MCContext &Ctx);
992
993
/// Create a machine code streamer which will print out assembly for the native
994
/// target, suitable for compiling with a native assembler.
995
///
996
/// \param InstPrint - If given, the instruction printer to use. If not given
997
/// the MCInst representation will be printed.  This method takes ownership of
998
/// InstPrint.
999
///
1000
/// \param CE - If given, a code emitter to use to show the instruction
1001
/// encoding inline with the assembly. This method takes ownership of \p CE.
1002
///
1003
/// \param TAB - If given, a target asm backend to use to show the fixup
1004
/// information in conjunction with encoding information. This method takes
1005
/// ownership of \p TAB.
1006
///
1007
/// \param ShowInst - Whether to show the MCInst representation inline with
1008
/// the assembly.
1009
MCStreamer *createAsmStreamer(MCContext &Ctx,
1010
                              std::unique_ptr<formatted_raw_ostream> OS,
1011
                              bool isVerboseAsm, bool useDwarfDirectory,
1012
                              MCInstPrinter *InstPrint, MCCodeEmitter *CE,
1013
                              MCAsmBackend *TAB, bool ShowInst);
1014
1015
} // end namespace llvm
1016
1017
#endif // LLVM_MC_MCSTREAMER_H