Coverage Report

Created: 2018-09-23 16:00

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/include/llvm/MC/MCStreamer.h
Line
Count
Source (jump to first uncovered line)
1
//===- MCStreamer.h - High-level Streaming Machine Code Output --*- C++ -*-===//
2
//
3
//                     The LLVM Compiler Infrastructure
4
//
5
// This file is distributed under the University of Illinois Open Source
6
// License. See LICENSE.TXT for details.
7
//
8
//===----------------------------------------------------------------------===//
9
//
10
// This file declares the MCStreamer class.
11
//
12
//===----------------------------------------------------------------------===//
13
14
#ifndef LLVM_MC_MCSTREAMER_H
15
#define LLVM_MC_MCSTREAMER_H
16
17
#include "llvm/ADT/ArrayRef.h"
18
#include "llvm/ADT/DenseMap.h"
19
#include "llvm/ADT/Optional.h"
20
#include "llvm/ADT/SmallVector.h"
21
#include "llvm/ADT/StringRef.h"
22
#include "llvm/MC/MCDirectives.h"
23
#include "llvm/MC/MCDwarf.h"
24
#include "llvm/MC/MCLinkerOptimizationHint.h"
25
#include "llvm/MC/MCSymbol.h"
26
#include "llvm/MC/MCWinEH.h"
27
#include "llvm/Support/Error.h"
28
#include "llvm/Support/MD5.h"
29
#include "llvm/Support/SMLoc.h"
30
#include "llvm/Support/TargetParser.h"
31
#include <cassert>
32
#include <cstdint>
33
#include <memory>
34
#include <string>
35
#include <utility>
36
#include <vector>
37
38
namespace llvm {
39
40
class AssemblerConstantPools;
41
class formatted_raw_ostream;
42
class MCAsmBackend;
43
class MCCodeEmitter;
44
struct MCCodePaddingContext;
45
class MCContext;
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:
62
/// * FooTargetStreamer : public MCTargetStreamer
63
/// * FooTargetAsmStreamer : public FooTargetStreamer
64
/// * 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:
85
  MCStreamer &Streamer;
86
87
public:
88
  MCTargetStreamer(MCStreamer &S);
89
  virtual ~MCTargetStreamer();
90
91
12.6k
  MCStreamer &getStreamer() { return Streamer; }
92
93
  // Allow a target to add behavior to the EmitLabel of MCStreamer.
94
  virtual void emitLabel(MCSymbol *Symbol);
95
  // 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
  virtual void finish();
113
};
114
115
// FIXME: declared here because it is used from
116
// lib/CodeGen/AsmPrinter/ARMException.cpp.
117
class ARMTargetStreamer : public MCTargetStreamer {
118
public:
119
  ARMTargetStreamer(MCStreamer &S);
120
  ~ARMTargetStreamer() override;
121
122
  virtual void emitFnStart();
123
  virtual void emitFnEnd();
124
  virtual void emitCantUnwind();
125
  virtual void emitPersonality(const MCSymbol *Personality);
126
  virtual void emitPersonalityIndex(unsigned Index);
127
  virtual void emitHandlerData();
128
  virtual void emitSetFP(unsigned FpReg, unsigned SpReg,
129
                         int64_t Offset = 0);
130
  virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
131
  virtual void emitPad(int64_t Offset);
132
  virtual void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
133
                           bool isVector);
134
  virtual void emitUnwindRaw(int64_t StackOffset,
135
                             const SmallVectorImpl<uint8_t> &Opcodes);
136
137
  virtual void switchVendor(StringRef Vendor);
138
  virtual void emitAttribute(unsigned Attribute, unsigned Value);
139
  virtual void emitTextAttribute(unsigned Attribute, StringRef String);
140
  virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
141
                                    StringRef StringValue = "");
142
  virtual void emitFPU(unsigned FPU);
143
  virtual void emitArch(ARM::ArchKind Arch);
144
  virtual void emitArchExtension(unsigned ArchExt);
145
  virtual void emitObjectArch(ARM::ArchKind Arch);
146
  void emitTargetAttributes(const MCSubtargetInfo &STI);
147
  virtual void finishAttributeSection();
148
  virtual void emitInst(uint32_t Inst, char Suffix = '\0');
149
150
  virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
151
152
  virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value);
153
154
  void finish() override;
155
156
  /// Reset any state between object emissions, i.e. the equivalent of
157
  /// MCStreamer's reset method.
158
  virtual void reset();
159
160
  /// Callback used to implement the ldr= pseudo.
161
  /// Add a new entry to the constant pool for the current section and return an
162
  /// MCExpr that can be used to refer to the constant pool location.
163
  const MCExpr *addConstantPoolEntry(const MCExpr *, SMLoc Loc);
164
165
  /// Callback used to implemnt the .ltorg directive.
166
  /// Emit contents of constant pool for the current section.
167
  void emitCurrentConstantPool();
168
169
private:
170
  std::unique_ptr<AssemblerConstantPools> ConstantPools;
171
};
172
173
/// Streaming machine code generation interface.
174
///
175
/// This interface is intended to provide a programatic interface that is very
176
/// similar to the level that an assembler .s file provides.  It has callbacks
177
/// to emit bytes, handle directives, etc.  The implementation of this interface
178
/// retains state to know what the current section is etc.
179
///
180
/// There are multiple implementations of this interface: one for writing out
181
/// a .s file, and implementations that write out .o files of various formats.
182
///
183
class MCStreamer {
184
  MCContext &Context;
185
  std::unique_ptr<MCTargetStreamer> TargetStreamer;
186
187
  std::vector<MCDwarfFrameInfo> DwarfFrameInfos;
188
  MCDwarfFrameInfo *getCurrentDwarfFrameInfo();
189
190
  /// Similar to DwarfFrameInfos, but for SEH unwind info. Chained frames may
191
  /// refer to each other, so use std::unique_ptr to provide pointer stability.
192
  std::vector<std::unique_ptr<WinEH::FrameInfo>> WinFrameInfos;
193
194
  WinEH::FrameInfo *CurrentWinFrameInfo;
195
196
  /// Retreive the current frame info if one is available and it is not yet
197
  /// closed. Otherwise, issue an error and return null.
198
  WinEH::FrameInfo *EnsureValidWinFrameInfo(SMLoc Loc);
199
200
  /// Tracks an index to represent the order a symbol was emitted in.
201
  /// Zero means we did not emit that symbol.
202
  DenseMap<const MCSymbol *, unsigned> SymbolOrdering;
203
204
  /// This is stack of current and previous section values saved by
205
  /// PushSection.
206
  SmallVector<std::pair<MCSectionSubPair, MCSectionSubPair>, 4> SectionStack;
207
208
  /// The next unique ID to use when creating a WinCFI-related section (.pdata
209
  /// or .xdata). This ID ensures that we have a one-to-one mapping from
210
  /// code section to unwind info section, which MSVC's incremental linker
211
  /// requires.
212
  unsigned NextWinCFIID = 0;
213
214
  bool UseAssemblerInfoForParsing;
215
216
protected:
217
  MCStreamer(MCContext &Ctx);
218
219
  virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
220
  virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
221
222
  /// When emitting an object file, create and emit a real label. When emitting
223
  /// textual assembly, this should do nothing to avoid polluting our output.
224
  virtual MCSymbol *EmitCFILabel();
225
226
551
  WinEH::FrameInfo *getCurrentWinFrameInfo() {
227
551
    return CurrentWinFrameInfo;
228
551
  }
229
230
  virtual void EmitWindowsUnwindTables();
231
232
  virtual void EmitRawTextImpl(StringRef String);
233
234
  /// Returns true if the the .cv_loc directive is in the right section.
235
  bool checkCVLocSection(unsigned FuncId, unsigned FileNo, SMLoc Loc);
236
237
public:
238
  MCStreamer(const MCStreamer &) = delete;
239
  MCStreamer &operator=(const MCStreamer &) = delete;
240
  virtual ~MCStreamer();
241
242
  void visitUsedExpr(const MCExpr &Expr);
243
  virtual void visitUsedSymbol(const MCSymbol &Sym);
244
245
26.8k
  void setTargetStreamer(MCTargetStreamer *TS) {
246
26.8k
    TargetStreamer.reset(TS);
247
26.8k
  }
248
249
  /// State management
250
  ///
251
  virtual void reset();
252
253
54.5M
  MCContext &getContext() const { return Context; }
254
255
862
  virtual MCAssembler *getAssemblerPtr() { return nullptr; }
256
257
18.2k
  void setUseAssemblerInfoForParsing(bool v) { UseAssemblerInfoForParsing = v; }
258
2.66M
  bool getUseAssemblerInfoForParsing() { return UseAssemblerInfoForParsing; }
259
260
12.5M
  MCTargetStreamer *getTargetStreamer() {
261
12.5M
    return TargetStreamer.get();
262
12.5M
  }
263
264
23.0k
  unsigned getNumFrameInfos() { return DwarfFrameInfos.size(); }
265
9.53k
  ArrayRef<MCDwarfFrameInfo> getDwarfFrameInfos() const {
266
9.53k
    return DwarfFrameInfos;
267
9.53k
  }
268
269
  bool hasUnfinishedDwarfFrameInfo();
270
271
379
  unsigned getNumWinFrameInfos() { return WinFrameInfos.size(); }
272
100
  ArrayRef<std::unique_ptr<WinEH::FrameInfo>> getWinFrameInfos() const {
273
100
    return WinFrameInfos;
274
100
  }
275
276
  void generateCompactUnwindEncodings(MCAsmBackend *MAB);
277
278
  /// \name Assembly File Formatting.
279
  /// @{
280
281
  /// Return true if this streamer supports verbose assembly and if it is
282
  /// enabled.
283
41.9k
  virtual bool isVerboseAsm() const { return false; }
284
285
  /// Return true if this asm streamer supports emitting unformatted text
286
  /// to the .s file with EmitRawText.
287
1.39M
  virtual bool hasRawTextSupport() const { return false; }
288
289
  /// Is the integrated assembler required for this streamer to function
290
  /// correctly?
291
1.87k
  virtual bool isIntegratedAssemblerRequired() const { return false; }
292
293
  /// Add a textual comment.
294
  ///
295
  /// Typically for comments that can be emitted to the generated .s
296
  /// file if applicable as a QoI issue to make the output of the compiler
297
  /// more readable.  This only affects the MCAsmStreamer, and only when
298
  /// verbose assembly output is enabled.
299
  ///
300
  /// If the comment includes embedded \n's, they will each get the comment
301
  /// prefix as appropriate.  The added comment should not end with a \n.
302
  /// By default, each comment is terminated with an end of line, i.e. the
303
  /// EOL param is set to true by default. If one prefers not to end the
304
  /// comment with a new line then the EOL param should be passed
305
  /// with a false value.
306
969k
  virtual void AddComment(const Twine &T, bool EOL = true) {}
307
308
  /// Return a raw_ostream that comments can be written to. Unlike
309
  /// AddComment, you are required to terminate comments with \n if you use this
310
  /// method.
311
  virtual raw_ostream &GetCommentOS();
312
313
  /// Print T and prefix it with the comment string (normally #) and
314
  /// optionally a tab. This prints the comment immediately, not at the end of
315
  /// the current line. It is basically a safe version of EmitRawText: since it
316
  /// only prints comments, the object streamer ignores it instead of asserting.
317
  virtual void emitRawComment(const Twine &T, bool TabPrefix = true);
318
319
  /// Add explicit comment T. T is required to be a valid
320
  /// comment in the output and does not need to be escaped.
321
  virtual void addExplicitComment(const Twine &T);
322
323
  /// Emit added explicit comments.
324
  virtual void emitExplicitComments();
325
326
  /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
327
960k
  virtual void AddBlankLine() {}
328
329
  /// @}
330
331
  /// \name Symbol & Section Management
332
  /// @{
333
334
  /// Return the current section that the streamer is emitting code to.
335
122M
  MCSectionSubPair getCurrentSection() const {
336
122M
    if (!SectionStack.empty())
337
122M
      return SectionStack.back().first;
338
18.4E
    return MCSectionSubPair();
339
18.4E
  }
340
122M
  MCSection *getCurrentSectionOnly() const { return getCurrentSection().first; }
341
342
  /// Return the previous section that the streamer is emitting code to.
343
15.4k
  MCSectionSubPair getPreviousSection() const {
344
15.4k
    if (!SectionStack.empty())
345
15.4k
      return SectionStack.back().second;
346
0
    return MCSectionSubPair();
347
0
  }
348
349
  /// Returns an index to represent the order a symbol was emitted in.
350
  /// (zero if we did not emit that symbol)
351
14
  unsigned GetSymbolOrder(const MCSymbol *Sym) const {
352
14
    return SymbolOrdering.lookup(Sym);
353
14
  }
354
355
  /// Update streamer for a new active section.
356
  ///
357
  /// This is called by PopSection and SwitchSection, if the current
358
  /// section changes.
359
  virtual void ChangeSection(MCSection *, const MCExpr *);
360
361
  /// Save the current and previous section on the section stack.
362
8.31k
  void PushSection() {
363
8.31k
    SectionStack.push_back(
364
8.31k
        std::make_pair(getCurrentSection(), getPreviousSection()));
365
8.31k
  }
366
367
  /// Restore the current and previous section from the section stack.
368
  /// Calls ChangeSection as needed.
369
  ///
370
  /// Returns false if the stack was empty.
371
8.31k
  bool PopSection() {
372
8.31k
    if (SectionStack.size() <= 1)
373
0
      return false;
374
8.31k
    auto I = SectionStack.end();
375
8.31k
    --I;
376
8.31k
    MCSectionSubPair OldSection = I->first;
377
8.31k
    --I;
378
8.31k
    MCSectionSubPair NewSection = I->first;
379
8.31k
380
8.31k
    if (OldSection != NewSection)
381
8.02k
      ChangeSection(NewSection.first, NewSection.second);
382
8.31k
    SectionStack.pop_back();
383
8.31k
    return true;
384
8.31k
  }
385
386
4
  bool SubSection(const MCExpr *Subsection) {
387
4
    if (SectionStack.empty())
388
0
      return false;
389
4
390
4
    SwitchSection(SectionStack.back().first.first, Subsection);
391
4
    return true;
392
4
  }
393
394
  /// Set the current section where code is being emitted to \p Section.  This
395
  /// is required to update CurSection.
396
  ///
397
  /// This corresponds to assembler directives like .section, .text, etc.
398
  virtual void SwitchSection(MCSection *Section,
399
                             const MCExpr *Subsection = nullptr);
400
401
  /// Set the current section where code is being emitted to \p Section.
402
  /// This is required to update CurSection. This version does not call
403
  /// ChangeSection.
404
  void SwitchSectionNoChange(MCSection *Section,
405
465
                             const MCExpr *Subsection = nullptr) {
406
465
    assert(Section && "Cannot switch to a null section!");
407
465
    MCSectionSubPair curSection = SectionStack.back().first;
408
465
    SectionStack.back().second = curSection;
409
465
    if (MCSectionSubPair(Section, Subsection) != curSection)
410
465
      SectionStack.back().first = MCSectionSubPair(Section, Subsection);
411
465
  }
412
413
  /// Create the default sections and set the initial one.
414
  virtual void InitSections(bool NoExecStack);
415
416
  MCSymbol *endSection(MCSection *Section);
417
418
  /// Sets the symbol's section.
419
  ///
420
  /// Each emitted symbol will be tracked in the ordering table,
421
  /// so we can sort on them later.
422
  void AssignFragment(MCSymbol *Symbol, MCFragment *Fragment);
423
424
  /// Emit a label for \p Symbol into the current section.
425
  ///
426
  /// This corresponds to an assembler statement such as:
427
  ///   foo:
428
  ///
429
  /// \param Symbol - The symbol to emit. A given symbol should only be
430
  /// emitted as a label once, and symbols emitted as a label should never be
431
  /// used in an assignment.
432
  // FIXME: These emission are non-const because we mutate the symbol to
433
  // add the section we're emitting it to later.
434
  virtual void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc());
435
436
  virtual void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol);
437
438
  /// Note in the output the specified \p Flag.
439
  virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
440
441
  /// Emit the given list \p Options of strings as linker
442
  /// options into the output.
443
0
  virtual void EmitLinkerOptions(ArrayRef<std::string> Kind) {}
444
445
  /// Note in the output the specified region \p Kind.
446
136
  virtual void EmitDataRegion(MCDataRegionType Kind) {}
447
448
  /// Specify the Mach-O minimum deployment target version.
449
  virtual void EmitVersionMin(MCVersionMinType Type, unsigned Major,
450
2
                              unsigned Minor, unsigned Update) {}
451
452
  /// Emit/Specify Mach-O build version command.
453
  /// \p Platform should be one of MachO::PlatformType.
454
  virtual void EmitBuildVersion(unsigned Platform, unsigned Major,
455
0
                                unsigned Minor, unsigned Update) {}
456
457
  void EmitVersionForTarget(const Triple &Target);
458
459
  /// Note in the output that the specified \p Func is a Thumb mode
460
  /// function (ARM target only).
461
  virtual void EmitThumbFunc(MCSymbol *Func);
462
463
  /// Emit an assignment of \p Value to \p Symbol.
464
  ///
465
  /// This corresponds to an assembler statement such as:
466
  ///  symbol = value
467
  ///
468
  /// The assignment generates no code, but has the side effect of binding the
469
  /// value in the current context. For the assembly streamer, this prints the
470
  /// binding into the .s file.
471
  ///
472
  /// \param Symbol - The symbol being assigned to.
473
  /// \param Value - The value for the symbol.
474
  virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
475
476
  /// Emit an weak reference from \p Alias to \p Symbol.
477
  ///
478
  /// This corresponds to an assembler statement such as:
479
  ///  .weakref alias, symbol
480
  ///
481
  /// \param Alias - The alias that is being created.
482
  /// \param Symbol - The symbol being aliased.
483
  virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
484
485
  /// Add the given \p Attribute to \p Symbol.
486
  virtual bool EmitSymbolAttribute(MCSymbol *Symbol,
487
                                   MCSymbolAttr Attribute) = 0;
488
489
  /// Set the \p DescValue for the \p Symbol.
490
  ///
491
  /// \param Symbol - The symbol to have its n_desc field set.
492
  /// \param DescValue - The value to set into the n_desc field.
493
  virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
494
495
  /// Start emitting COFF symbol definition
496
  ///
497
  /// \param Symbol - The symbol to have its External & Type fields set.
498
  virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
499
500
  /// Emit the storage class of the symbol.
501
  ///
502
  /// \param StorageClass - The storage class the symbol should have.
503
  virtual void EmitCOFFSymbolStorageClass(int StorageClass);
504
505
  /// Emit the type of the symbol.
506
  ///
507
  /// \param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
508
  virtual void EmitCOFFSymbolType(int Type);
509
510
  /// Marks the end of the symbol definition.
511
  virtual void EndCOFFSymbolDef();
512
513
  virtual void EmitCOFFSafeSEH(MCSymbol const *Symbol);
514
515
  /// Emits the symbol table index of a Symbol into the current section.
516
  virtual void EmitCOFFSymbolIndex(MCSymbol const *Symbol);
517
518
  /// Emits a COFF section index.
519
  ///
520
  /// \param Symbol - Symbol the section number relocation should point to.
521
  virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
522
523
  /// Emits a COFF section relative relocation.
524
  ///
525
  /// \param Symbol - Symbol the section relative relocation should point to.
526
  virtual void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset);
527
528
  /// Emits a COFF image relative relocation.
529
  ///
530
  /// \param Symbol - Symbol the image relative relocation should point to.
531
  virtual void EmitCOFFImgRel32(MCSymbol const *Symbol, int64_t Offset);
532
533
  /// Emit an ELF .size directive.
534
  ///
535
  /// This corresponds to an assembler statement such as:
536
  ///  .size symbol, expression
537
  virtual void emitELFSize(MCSymbol *Symbol, const MCExpr *Value);
538
539
  /// Emit an ELF .symver directive.
540
  ///
541
  /// This corresponds to an assembler statement such as:
542
  ///  .symver _start, foo@@SOME_VERSION
543
  /// \param AliasName - The versioned alias (i.e. "foo@@SOME_VERSION")
544
  /// \param Aliasee - The aliased symbol (i.e. "_start")
545
  virtual void emitELFSymverDirective(StringRef AliasName,
546
                                      const MCSymbol *Aliasee);
547
548
  /// Emit a Linker Optimization Hint (LOH) directive.
549
  /// \param Args - Arguments of the LOH.
550
0
  virtual void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {}
551
552
  /// Emit a common symbol.
553
  ///
554
  /// \param Symbol - The common symbol to emit.
555
  /// \param Size - The size of the common symbol.
556
  /// \param ByteAlignment - The alignment of the symbol if
557
  /// non-zero. This must be a power of 2.
558
  virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
559
                                unsigned ByteAlignment) = 0;
560
561
  /// Emit a local common (.lcomm) symbol.
562
  ///
563
  /// \param Symbol - The common symbol to emit.
564
  /// \param Size - The size of the common symbol.
565
  /// \param ByteAlignment - The alignment of the common symbol in bytes.
566
  virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
567
                                     unsigned ByteAlignment);
568
569
  /// Emit the zerofill section and an optional symbol.
570
  ///
571
  /// \param Section - The zerofill section to create and or to put the symbol
572
  /// \param Symbol - The zerofill symbol to emit, if non-NULL.
573
  /// \param Size - The size of the zerofill symbol.
574
  /// \param ByteAlignment - The alignment of the zerofill symbol if
575
  /// non-zero. This must be a power of 2 on some targets.
576
  virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
577
                            uint64_t Size = 0, unsigned ByteAlignment = 0,
578
                            SMLoc Loc = SMLoc()) = 0;
579
580
  /// Emit a thread local bss (.tbss) symbol.
581
  ///
582
  /// \param Section - The thread local common section.
583
  /// \param Symbol - The thread local common symbol to emit.
584
  /// \param Size - The size of the symbol.
585
  /// \param ByteAlignment - The alignment of the thread local common symbol
586
  /// if non-zero.  This must be a power of 2 on some targets.
587
  virtual void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
588
                              uint64_t Size, unsigned ByteAlignment = 0);
589
590
  /// @}
591
  /// \name Generating Data
592
  /// @{
593
594
  /// Emit the bytes in \p Data into the output.
595
  ///
596
  /// This is used to implement assembler directives such as .byte, .ascii,
597
  /// etc.
598
  virtual void EmitBytes(StringRef Data);
599
600
  /// Functionally identical to EmitBytes. When emitting textual assembly, this
601
  /// method uses .byte directives instead of .ascii or .asciz for readability.
602
  virtual void EmitBinaryData(StringRef Data);
603
604
  /// Emit the expression \p Value into the output as a native
605
  /// integer of the given \p Size bytes.
606
  ///
607
  /// This is used to implement assembler directives such as .word, .quad,
608
  /// etc.
609
  ///
610
  /// \param Value - The value to emit.
611
  /// \param Size - The size of the integer (in bytes) to emit. This must
612
  /// match a native machine width.
613
  /// \param Loc - The location of the expression for error reporting.
614
  virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
615
                             SMLoc Loc = SMLoc());
616
617
  void EmitValue(const MCExpr *Value, unsigned Size, SMLoc Loc = SMLoc());
618
619
  /// Special case of EmitValue that avoids the client having
620
  /// to pass in a MCExpr for constant integers.
621
  virtual void EmitIntValue(uint64_t Value, unsigned Size);
622
623
  virtual void EmitULEB128Value(const MCExpr *Value);
624
625
  virtual void EmitSLEB128Value(const MCExpr *Value);
626
627
  /// Special case of EmitULEB128Value that avoids the client having to
628
  /// pass in a MCExpr for constant integers.
629
  void EmitULEB128IntValue(uint64_t Value);
630
631
  /// Special case of EmitSLEB128Value that avoids the client having to
632
  /// pass in a MCExpr for constant integers.
633
  void EmitSLEB128IntValue(int64_t Value);
634
635
  /// Special case of EmitValue that avoids the client having to pass in
636
  /// a MCExpr for MCSymbols.
637
  void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
638
                       bool IsSectionRelative = false);
639
640
  /// Emit the expression \p Value into the output as a dtprel
641
  /// (64-bit DTP relative) value.
642
  ///
643
  /// This is used to implement assembler directives such as .dtpreldword on
644
  /// targets that support them.
645
  virtual void EmitDTPRel64Value(const MCExpr *Value);
646
647
  /// Emit the expression \p Value into the output as a dtprel
648
  /// (32-bit DTP relative) value.
649
  ///
650
  /// This is used to implement assembler directives such as .dtprelword on
651
  /// targets that support them.
652
  virtual void EmitDTPRel32Value(const MCExpr *Value);
653
654
  /// Emit the expression \p Value into the output as a tprel
655
  /// (64-bit TP relative) value.
656
  ///
657
  /// This is used to implement assembler directives such as .tpreldword on
658
  /// targets that support them.
659
  virtual void EmitTPRel64Value(const MCExpr *Value);
660
661
  /// Emit the expression \p Value into the output as a tprel
662
  /// (32-bit TP relative) value.
663
  ///
664
  /// This is used to implement assembler directives such as .tprelword on
665
  /// targets that support them.
666
  virtual void EmitTPRel32Value(const MCExpr *Value);
667
668
  /// Emit the expression \p Value into the output as a gprel64 (64-bit
669
  /// GP relative) value.
670
  ///
671
  /// This is used to implement assembler directives such as .gpdword on
672
  /// targets that support them.
673
  virtual void EmitGPRel64Value(const MCExpr *Value);
674
675
  /// Emit the expression \p Value into the output as a gprel32 (32-bit
676
  /// GP relative) value.
677
  ///
678
  /// This is used to implement assembler directives such as .gprel32 on
679
  /// targets that support them.
680
  virtual void EmitGPRel32Value(const MCExpr *Value);
681
682
  /// Emit NumBytes bytes worth of the value specified by FillValue.
683
  /// This implements directives such as '.space'.
684
  void emitFill(uint64_t NumBytes, uint8_t FillValue);
685
686
  /// Emit \p Size bytes worth of the value specified by \p FillValue.
687
  ///
688
  /// This is used to implement assembler directives such as .space or .skip.
689
  ///
690
  /// \param NumBytes - The number of bytes to emit.
691
  /// \param FillValue - The value to use when filling bytes.
692
  /// \param Loc - The location of the expression for error reporting.
693
  virtual void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
694
                        SMLoc Loc = SMLoc());
695
696
  /// Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is
697
  /// taken from the lowest order 4 bytes of \p Expr expression.
698
  ///
699
  /// This is used to implement assembler directives such as .fill.
700
  ///
701
  /// \param NumValues - The number of copies of \p Size bytes to emit.
702
  /// \param Size - The size (in bytes) of each repeated value.
703
  /// \param Expr - The expression from which \p Size bytes are used.
704
  virtual void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
705
                        SMLoc Loc = SMLoc());
706
707
  /// Emit NumBytes worth of zeros.
708
  /// This function properly handles data in virtual sections.
709
  void EmitZeros(uint64_t NumBytes);
710
711
  /// Emit some number of copies of \p Value until the byte alignment \p
712
  /// ByteAlignment is reached.
713
  ///
714
  /// If the number of bytes need to emit for the alignment is not a multiple
715
  /// of \p ValueSize, then the contents of the emitted fill bytes is
716
  /// undefined.
717
  ///
718
  /// This used to implement the .align assembler directive.
719
  ///
720
  /// \param ByteAlignment - The alignment to reach. This must be a power of
721
  /// two on some targets.
722
  /// \param Value - The value to use when filling bytes.
723
  /// \param ValueSize - The size of the integer (in bytes) to emit for
724
  /// \p Value. This must match a native machine width.
725
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
726
  /// the alignment cannot be reached in this many bytes, no bytes are
727
  /// emitted.
728
  virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
729
                                    unsigned ValueSize = 1,
730
                                    unsigned MaxBytesToEmit = 0);
731
732
  /// Emit nops until the byte alignment \p ByteAlignment is reached.
733
  ///
734
  /// This used to align code where the alignment bytes may be executed.  This
735
  /// can emit different bytes for different sizes to optimize execution.
736
  ///
737
  /// \param ByteAlignment - The alignment to reach. This must be a power of
738
  /// two on some targets.
739
  /// \param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
740
  /// the alignment cannot be reached in this many bytes, no bytes are
741
  /// emitted.
742
  virtual void EmitCodeAlignment(unsigned ByteAlignment,
743
                                 unsigned MaxBytesToEmit = 0);
744
745
  /// Emit some number of copies of \p Value until the byte offset \p
746
  /// Offset is reached.
747
  ///
748
  /// This is used to implement assembler directives such as .org.
749
  ///
750
  /// \param Offset - The offset to reach. This may be an expression, but the
751
  /// expression must be associated with the current section.
752
  /// \param Value - The value to use when filling bytes.
753
  virtual void emitValueToOffset(const MCExpr *Offset, unsigned char Value,
754
                                 SMLoc Loc);
755
756
  virtual void
757
227k
  EmitCodePaddingBasicBlockStart(const MCCodePaddingContext &Context) {}
758
759
  virtual void
760
227k
  EmitCodePaddingBasicBlockEnd(const MCCodePaddingContext &Context) {}
761
762
  /// @}
763
764
  /// Switch to a new logical file.  This is used to implement the '.file
765
  /// "foo.c"' assembler directive.
766
  virtual void EmitFileDirective(StringRef Filename);
767
768
  /// Emit the "identifiers" directive.  This implements the
769
  /// '.ident "version foo"' assembler directive.
770
3
  virtual void EmitIdent(StringRef IdentString) {}
771
772
  /// Associate a filename with a specified logical file number.  This
773
  /// implements the DWARF2 '.file 4 "foo.c"' assembler directive.
774
  unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
775
                                  StringRef Filename,
776
                                  MD5::MD5Result *Checksum = nullptr,
777
                                  Optional<StringRef> Source = None,
778
1.36M
                                  unsigned CUID = 0) {
779
1.36M
    return cantFail(
780
1.36M
        tryEmitDwarfFileDirective(FileNo, Directory, Filename, Checksum,
781
1.36M
                                  Source, CUID));
782
1.36M
  }
783
784
  /// Associate a filename with a specified logical file number.
785
  /// Also associate a directory, optional checksum, and optional source
786
  /// text with the logical file.  This implements the DWARF2
787
  /// '.file 4 "dir/foo.c"' assembler directive, and the DWARF5
788
  /// '.file 4 "dir/foo.c" md5 "..." source "..."' assembler directive.
789
  virtual Expected<unsigned> tryEmitDwarfFileDirective(
790
      unsigned FileNo, StringRef Directory, StringRef Filename,
791
      MD5::MD5Result *Checksum = nullptr, Optional<StringRef> Source = None,
792
      unsigned CUID = 0);
793
794
  /// Specify the "root" file of the compilation, using the ".file 0" extension.
795
  virtual void emitDwarfFile0Directive(StringRef Directory, StringRef Filename,
796
                                       MD5::MD5Result *Checksum,
797
                                       Optional<StringRef> Source,
798
                                       unsigned CUID = 0);
799
800
  /// This implements the DWARF2 '.loc fileno lineno ...' assembler
801
  /// directive.
802
  virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
803
                                     unsigned Column, unsigned Flags,
804
                                     unsigned Isa, unsigned Discriminator,
805
                                     StringRef FileName);
806
807
  /// Associate a filename with a specified logical file number, and also
808
  /// specify that file's checksum information.  This implements the '.cv_file 4
809
  /// "foo.c"' assembler directive. Returns true on success.
810
  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename,
811
                                   ArrayRef<uint8_t> Checksum,
812
                                   unsigned ChecksumKind);
813
814
  /// Introduces a function id for use with .cv_loc.
815
  virtual bool EmitCVFuncIdDirective(unsigned FunctionId);
816
817
  /// Introduces an inline call site id for use with .cv_loc. Includes
818
  /// extra information for inline line table generation.
819
  virtual bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
820
                                           unsigned IAFile, unsigned IALine,
821
                                           unsigned IACol, SMLoc Loc);
822
823
  /// This implements the CodeView '.cv_loc' assembler directive.
824
  virtual void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
825
                                  unsigned Line, unsigned Column,
826
                                  bool PrologueEnd, bool IsStmt,
827
                                  StringRef FileName, SMLoc Loc);
828
829
  /// This implements the CodeView '.cv_linetable' assembler directive.
830
  virtual void EmitCVLinetableDirective(unsigned FunctionId,
831
                                        const MCSymbol *FnStart,
832
                                        const MCSymbol *FnEnd);
833
834
  /// This implements the CodeView '.cv_inline_linetable' assembler
835
  /// directive.
836
  virtual void EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
837
                                              unsigned SourceFileId,
838
                                              unsigned SourceLineNum,
839
                                              const MCSymbol *FnStartSym,
840
                                              const MCSymbol *FnEndSym);
841
842
  /// This implements the CodeView '.cv_def_range' assembler
843
  /// directive.
844
  virtual void EmitCVDefRangeDirective(
845
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
846
      StringRef FixedSizePortion);
847
848
  /// This implements the CodeView '.cv_stringtable' assembler directive.
849
0
  virtual void EmitCVStringTableDirective() {}
850
851
  /// This implements the CodeView '.cv_filechecksums' assembler directive.
852
0
  virtual void EmitCVFileChecksumsDirective() {}
853
854
  /// This implements the CodeView '.cv_filechecksumoffset' assembler
855
  /// directive.
856
0
  virtual void EmitCVFileChecksumOffsetDirective(unsigned FileNo) {}
857
858
  /// This implements the CodeView '.cv_fpo_data' assembler directive.
859
0
  virtual void EmitCVFPOData(const MCSymbol *ProcSym, SMLoc Loc = {}) {}
860
861
  /// Emit the absolute difference between two symbols.
862
  ///
863
  /// \pre Offset of \c Hi is greater than the offset \c Lo.
864
  virtual void emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
865
                                      unsigned Size);
866
867
  /// Emit the absolute difference between two symbols encoded with ULEB128.
868
  virtual void emitAbsoluteSymbolDiffAsULEB128(const MCSymbol *Hi,
869
                                               const MCSymbol *Lo);
870
871
  virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
872
  virtual void EmitCFISections(bool EH, bool Debug);
873
  void EmitCFIStartProc(bool IsSimple);
874
  void EmitCFIEndProc();
875
  virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
876
  virtual void EmitCFIDefCfaOffset(int64_t Offset);
877
  virtual void EmitCFIDefCfaRegister(int64_t Register);
878
  virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
879
  virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
880
  virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
881
  virtual void EmitCFIRememberState();
882
  virtual void EmitCFIRestoreState();
883
  virtual void EmitCFISameValue(int64_t Register);
884
  virtual void EmitCFIRestore(int64_t Register);
885
  virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
886
  virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
887
  virtual void EmitCFIEscape(StringRef Values);
888
  virtual void EmitCFIReturnColumn(int64_t Register);
889
  virtual void EmitCFIGnuArgsSize(int64_t Size);
890
  virtual void EmitCFISignalFrame();
891
  virtual void EmitCFIUndefined(int64_t Register);
892
  virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
893
  virtual void EmitCFIWindowSave();
894
895
  virtual void EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc = SMLoc());
896
  virtual void EmitWinCFIEndProc(SMLoc Loc = SMLoc());
897
  virtual void EmitWinCFIStartChained(SMLoc Loc = SMLoc());
898
  virtual void EmitWinCFIEndChained(SMLoc Loc = SMLoc());
899
  virtual void EmitWinCFIPushReg(unsigned Register, SMLoc Loc = SMLoc());
900
  virtual void EmitWinCFISetFrame(unsigned Register, unsigned Offset,
901
                                  SMLoc Loc = SMLoc());
902
  virtual void EmitWinCFIAllocStack(unsigned Size, SMLoc Loc = SMLoc());
903
  virtual void EmitWinCFISaveReg(unsigned Register, unsigned Offset,
904
                                 SMLoc Loc = SMLoc());
905
  virtual void EmitWinCFISaveXMM(unsigned Register, unsigned Offset,
906
                                 SMLoc Loc = SMLoc());
907
  virtual void EmitWinCFIPushFrame(bool Code, SMLoc Loc = SMLoc());
908
  virtual void EmitWinCFIEndProlog(SMLoc Loc = SMLoc());
909
  virtual void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except,
910
                                SMLoc Loc = SMLoc());
911
  virtual void EmitWinEHHandlerData(SMLoc Loc = SMLoc());
912
913
  virtual void emitCGProfileEntry(const MCSymbolRefExpr *From,
914
                                  const MCSymbolRefExpr *To, uint64_t Count);
915
916
  /// Get the .pdata section used for the given section. Typically the given
917
  /// section is either the main .text section or some other COMDAT .text
918
  /// section, but it may be any section containing code.
919
  MCSection *getAssociatedPDataSection(const MCSection *TextSec);
920
921
  /// Get the .xdata section used for the given section.
922
  MCSection *getAssociatedXDataSection(const MCSection *TextSec);
923
924
  virtual void EmitSyntaxDirective();
925
926
  /// Emit a .reloc directive.
927
  /// Returns true if the relocation could not be emitted because Name is not
928
  /// known.
929
  virtual bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
930
                                  const MCExpr *Expr, SMLoc Loc,
931
0
                                  const MCSubtargetInfo &STI) {
932
0
    return true;
933
0
  }
934
935
0
  virtual void EmitAddrsig() {}
936
0
  virtual void EmitAddrsigSym(const MCSymbol *Sym) {}
937
938
  /// Emit the given \p Instruction into the current section.
939
  /// PrintSchedInfo == true then schedul comment should be added to output
940
  virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
941
                               bool PrintSchedInfo = false);
942
943
  /// Set the bundle alignment mode from now on in the section.
944
  /// The argument is the power of 2 to which the alignment is set. The
945
  /// value 0 means turn the bundle alignment off.
946
  virtual void EmitBundleAlignMode(unsigned AlignPow2);
947
948
  /// The following instructions are a bundle-locked group.
949
  ///
950
  /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
951
  ///                     the end of a bundle.
952
  virtual void EmitBundleLock(bool AlignToEnd);
953
954
  /// Ends a bundle-locked group.
955
  virtual void EmitBundleUnlock();
956
957
  /// If this file is backed by a assembly streamer, this dumps the
958
  /// specified string in the output .s file.  This capability is indicated by
959
  /// the hasRawTextSupport() predicate.  By default this aborts.
960
  void EmitRawText(const Twine &String);
961
962
  /// Streamer specific finalization.
963
  virtual void FinishImpl();
964
  /// Finish emission of machine code.
965
  void Finish();
966
967
6
  virtual bool mayHaveInstructions(MCSection &Sec) const { return true; }
968
};
969
970
/// Create a dummy machine code streamer, which does nothing. This is useful for
971
/// timing the assembler front end.
972
MCStreamer *createNullStreamer(MCContext &Ctx);
973
974
/// Create a machine code streamer which will print out assembly for the native
975
/// target, suitable for compiling with a native assembler.
976
///
977
/// \param InstPrint - If given, the instruction printer to use. If not given
978
/// the MCInst representation will be printed.  This method takes ownership of
979
/// InstPrint.
980
///
981
/// \param CE - If given, a code emitter to use to show the instruction
982
/// encoding inline with the assembly. This method takes ownership of \p CE.
983
///
984
/// \param TAB - If given, a target asm backend to use to show the fixup
985
/// information in conjunction with encoding information. This method takes
986
/// ownership of \p TAB.
987
///
988
/// \param ShowInst - Whether to show the MCInst representation inline with
989
/// the assembly.
990
MCStreamer *createAsmStreamer(MCContext &Ctx,
991
                              std::unique_ptr<formatted_raw_ostream> OS,
992
                              bool isVerboseAsm, bool useDwarfDirectory,
993
                              MCInstPrinter *InstPrint, MCCodeEmitter *CE,
994
                              MCAsmBackend *TAB, bool ShowInst);
995
996
} // end namespace llvm
997
998
#endif // LLVM_MC_MCSTREAMER_H