LLVM  7.0.0svn
MCMachOStreamer.cpp
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1 //===- MCMachOStreamer.cpp - MachO Streamer -------------------------------===//
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 #include "llvm/ADT/DenseMap.h"
11 #include "llvm/ADT/SmallString.h"
12 #include "llvm/ADT/SmallVector.h"
13 #include "llvm/ADT/StringRef.h"
14 #include "llvm/ADT/Triple.h"
15 #include "llvm/MC/MCAsmBackend.h"
16 #include "llvm/MC/MCAssembler.h"
17 #include "llvm/MC/MCCodeEmitter.h"
18 #include "llvm/MC/MCContext.h"
19 #include "llvm/MC/MCDirectives.h"
20 #include "llvm/MC/MCExpr.h"
21 #include "llvm/MC/MCFixup.h"
22 #include "llvm/MC/MCFragment.h"
23 #include "llvm/MC/MCInst.h"
27 #include "llvm/MC/MCSection.h"
28 #include "llvm/MC/MCSectionMachO.h"
29 #include "llvm/MC/MCStreamer.h"
30 #include "llvm/MC/MCSymbol.h"
31 #include "llvm/MC/MCSymbolMachO.h"
32 #include "llvm/MC/MCValue.h"
33 #include "llvm/Support/Casting.h"
37 #include <cassert>
38 #include <vector>
39 
40 using namespace llvm;
41 
42 namespace {
43 
44 class MCMachOStreamer : public MCObjectStreamer {
45 private:
46  /// LabelSections - true if each section change should emit a linker local
47  /// label for use in relocations for assembler local references. Obviates the
48  /// need for local relocations. False by default.
49  bool LabelSections;
50 
51  bool DWARFMustBeAtTheEnd;
52  bool CreatedADWARFSection;
53 
54  /// HasSectionLabel - map of which sections have already had a non-local
55  /// label emitted to them. Used so we don't emit extraneous linker local
56  /// labels in the middle of the section.
57  DenseMap<const MCSection*, bool> HasSectionLabel;
58 
59  void EmitInstToData(const MCInst &Inst, const MCSubtargetInfo &STI) override;
60 
61  void EmitDataRegion(DataRegionData::KindTy Kind);
62  void EmitDataRegionEnd();
63 
64 public:
65  MCMachOStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> MAB,
66  raw_pwrite_stream &OS, std::unique_ptr<MCCodeEmitter> Emitter,
67  bool DWARFMustBeAtTheEnd, bool label)
68  : MCObjectStreamer(Context, std::move(MAB), OS, std::move(Emitter)),
69  LabelSections(label), DWARFMustBeAtTheEnd(DWARFMustBeAtTheEnd),
70  CreatedADWARFSection(false) {}
71 
72  /// state management
73  void reset() override {
74  CreatedADWARFSection = false;
75  HasSectionLabel.clear();
77  }
78 
79  /// @name MCStreamer Interface
80  /// @{
81 
82  void ChangeSection(MCSection *Sect, const MCExpr *Subsect) override;
83  void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
84  void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override;
85  void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol) override;
86  void EmitAssemblerFlag(MCAssemblerFlag Flag) override;
87  void EmitLinkerOptions(ArrayRef<std::string> Options) override;
88  void EmitDataRegion(MCDataRegionType Kind) override;
89  void EmitVersionMin(MCVersionMinType Kind, unsigned Major,
90  unsigned Minor, unsigned Update) override;
91  void EmitBuildVersion(unsigned Platform, unsigned Major,
92  unsigned Minor, unsigned Update) override;
93  void EmitThumbFunc(MCSymbol *Func) override;
94  bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
95  void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override;
96  void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
97  unsigned ByteAlignment) override;
98 
99  void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
100  unsigned ByteAlignment) override;
101  void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
102  uint64_t Size = 0, unsigned ByteAlignment = 0) override;
103  void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
104  unsigned ByteAlignment = 0) override;
105 
106  void EmitIdent(StringRef IdentString) override {
107  llvm_unreachable("macho doesn't support this directive");
108  }
109 
110  void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) override {
111  getAssembler().getLOHContainer().addDirective(Kind, Args);
112  }
113 
114  void FinishImpl() override;
115 };
116 
117 } // end anonymous namespace.
118 
119 static bool canGoAfterDWARF(const MCSectionMachO &MSec) {
120  // These sections are created by the assembler itself after the end of
121  // the .s file.
122  StringRef SegName = MSec.getSegmentName();
123  StringRef SecName = MSec.getSectionName();
124 
125  if (SegName == "__LD" && SecName == "__compact_unwind")
126  return true;
127 
128  if (SegName == "__IMPORT") {
129  if (SecName == "__jump_table")
130  return true;
131 
132  if (SecName == "__pointers")
133  return true;
134  }
135 
136  if (SegName == "__TEXT" && SecName == "__eh_frame")
137  return true;
138 
139  if (SegName == "__DATA" && (SecName == "__nl_symbol_ptr" ||
140  SecName == "__thread_ptr"))
141  return true;
142 
143  return false;
144 }
145 
146 void MCMachOStreamer::ChangeSection(MCSection *Section,
147  const MCExpr *Subsection) {
148  // Change the section normally.
149  bool Created = changeSectionImpl(Section, Subsection);
150  const MCSectionMachO &MSec = *cast<MCSectionMachO>(Section);
151  StringRef SegName = MSec.getSegmentName();
152  if (SegName == "__DWARF")
153  CreatedADWARFSection = true;
154  else if (Created && DWARFMustBeAtTheEnd && !canGoAfterDWARF(MSec))
155  assert(!CreatedADWARFSection && "Creating regular section after DWARF");
156 
157  // Output a linker-local symbol so we don't need section-relative local
158  // relocations. The linker hates us when we do that.
159  if (LabelSections && !HasSectionLabel[Section] &&
160  !Section->getBeginSymbol()) {
161  MCSymbol *Label = getContext().createLinkerPrivateTempSymbol();
162  Section->setBeginSymbol(Label);
163  HasSectionLabel[Section] = true;
164  }
165 }
166 
167 void MCMachOStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
168  MCSymbol *EHSymbol) {
169  getAssembler().registerSymbol(*Symbol);
170  if (Symbol->isExternal())
171  EmitSymbolAttribute(EHSymbol, MCSA_Global);
172  if (cast<MCSymbolMachO>(Symbol)->isWeakDefinition())
173  EmitSymbolAttribute(EHSymbol, MCSA_WeakDefinition);
174  if (Symbol->isPrivateExtern())
175  EmitSymbolAttribute(EHSymbol, MCSA_PrivateExtern);
176 }
177 
178 void MCMachOStreamer::EmitLabel(MCSymbol *Symbol, SMLoc Loc) {
179  // We have to create a new fragment if this is an atom defining symbol,
180  // fragments cannot span atoms.
181  if (getAssembler().isSymbolLinkerVisible(*Symbol))
182  insert(new MCDataFragment());
183 
184  MCObjectStreamer::EmitLabel(Symbol, Loc);
185 
186  // This causes the reference type flag to be cleared. Darwin 'as' was "trying"
187  // to clear the weak reference and weak definition bits too, but the
188  // implementation was buggy. For now we just try to match 'as', for
189  // diffability.
190  //
191  // FIXME: Cleanup this code, these bits should be emitted based on semantic
192  // properties, not on the order of definition, etc.
193  cast<MCSymbolMachO>(Symbol)->clearReferenceType();
194 }
195 
196 void MCMachOStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
197  MCValue Res;
198 
199  if (Value->evaluateAsRelocatable(Res, nullptr, nullptr)) {
200  if (const MCSymbolRefExpr *SymAExpr = Res.getSymA()) {
201  const MCSymbol &SymA = SymAExpr->getSymbol();
202  if (!Res.getSymB() && (SymA.getName() == "" || Res.getConstant() != 0))
203  cast<MCSymbolMachO>(Symbol)->setAltEntry();
204  }
205  }
206  MCObjectStreamer::EmitAssignment(Symbol, Value);
207 }
208 
209 void MCMachOStreamer::EmitDataRegion(DataRegionData::KindTy Kind) {
210  // Create a temporary label to mark the start of the data region.
211  MCSymbol *Start = getContext().createTempSymbol();
212  EmitLabel(Start);
213  // Record the region for the object writer to use.
214  DataRegionData Data = { Kind, Start, nullptr };
215  std::vector<DataRegionData> &Regions = getAssembler().getDataRegions();
216  Regions.push_back(Data);
217 }
218 
219 void MCMachOStreamer::EmitDataRegionEnd() {
220  std::vector<DataRegionData> &Regions = getAssembler().getDataRegions();
221  assert(!Regions.empty() && "Mismatched .end_data_region!");
222  DataRegionData &Data = Regions.back();
223  assert(!Data.End && "Mismatched .end_data_region!");
224  // Create a temporary label to mark the end of the data region.
225  Data.End = getContext().createTempSymbol();
226  EmitLabel(Data.End);
227 }
228 
229 void MCMachOStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
230  // Let the target do whatever target specific stuff it needs to do.
231  getAssembler().getBackend().handleAssemblerFlag(Flag);
232  // Do any generic stuff we need to do.
233  switch (Flag) {
234  case MCAF_SyntaxUnified: return; // no-op here.
235  case MCAF_Code16: return; // Change parsing mode; no-op here.
236  case MCAF_Code32: return; // Change parsing mode; no-op here.
237  case MCAF_Code64: return; // Change parsing mode; no-op here.
239  getAssembler().setSubsectionsViaSymbols(true);
240  return;
241  }
242 }
243 
244 void MCMachOStreamer::EmitLinkerOptions(ArrayRef<std::string> Options) {
245  getAssembler().getLinkerOptions().push_back(Options);
246 }
247 
248 void MCMachOStreamer::EmitDataRegion(MCDataRegionType Kind) {
249  switch (Kind) {
250  case MCDR_DataRegion:
251  EmitDataRegion(DataRegionData::Data);
252  return;
253  case MCDR_DataRegionJT8:
254  EmitDataRegion(DataRegionData::JumpTable8);
255  return;
256  case MCDR_DataRegionJT16:
257  EmitDataRegion(DataRegionData::JumpTable16);
258  return;
259  case MCDR_DataRegionJT32:
260  EmitDataRegion(DataRegionData::JumpTable32);
261  return;
262  case MCDR_DataRegionEnd:
263  EmitDataRegionEnd();
264  return;
265  }
266 }
267 
268 void MCMachOStreamer::EmitVersionMin(MCVersionMinType Kind, unsigned Major,
269  unsigned Minor, unsigned Update) {
270  getAssembler().setVersionMin(Kind, Major, Minor, Update);
271 }
272 
273 void MCMachOStreamer::EmitBuildVersion(unsigned Platform, unsigned Major,
274  unsigned Minor, unsigned Update) {
275  getAssembler().setBuildVersion((MachO::PlatformType)Platform, Major, Minor,
276  Update);
277 }
278 
279 void MCMachOStreamer::EmitThumbFunc(MCSymbol *Symbol) {
280  // Remember that the function is a thumb function. Fixup and relocation
281  // values will need adjusted.
282  getAssembler().setIsThumbFunc(Symbol);
283  cast<MCSymbolMachO>(Symbol)->setThumbFunc();
284 }
285 
286 bool MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Sym,
288  MCSymbolMachO *Symbol = cast<MCSymbolMachO>(Sym);
289 
290  // Indirect symbols are handled differently, to match how 'as' handles
291  // them. This makes writing matching .o files easier.
292  if (Attribute == MCSA_IndirectSymbol) {
293  // Note that we intentionally cannot use the symbol data here; this is
294  // important for matching the string table that 'as' generates.
295  IndirectSymbolData ISD;
296  ISD.Symbol = Symbol;
297  ISD.Section = getCurrentSectionOnly();
298  getAssembler().getIndirectSymbols().push_back(ISD);
299  return true;
300  }
301 
302  // Adding a symbol attribute always introduces the symbol, note that an
303  // important side effect of calling registerSymbol here is to register
304  // the symbol with the assembler.
305  getAssembler().registerSymbol(*Symbol);
306 
307  // The implementation of symbol attributes is designed to match 'as', but it
308  // leaves much to desired. It doesn't really make sense to arbitrarily add and
309  // remove flags, but 'as' allows this (in particular, see .desc).
310  //
311  // In the future it might be worth trying to make these operations more well
312  // defined.
313  switch (Attribute) {
314  case MCSA_Invalid:
317  case MCSA_ELF_TypeObject:
318  case MCSA_ELF_TypeTLS:
319  case MCSA_ELF_TypeCommon:
320  case MCSA_ELF_TypeNoType:
322  case MCSA_Hidden:
323  case MCSA_IndirectSymbol:
324  case MCSA_Internal:
325  case MCSA_Protected:
326  case MCSA_Weak:
327  case MCSA_Local:
328  return false;
329 
330  case MCSA_Global:
331  Symbol->setExternal(true);
332  // This effectively clears the undefined lazy bit, in Darwin 'as', although
333  // it isn't very consistent because it implements this as part of symbol
334  // lookup.
335  //
336  // FIXME: Cleanup this code, these bits should be emitted based on semantic
337  // properties, not on the order of definition, etc.
338  Symbol->setReferenceTypeUndefinedLazy(false);
339  break;
340 
341  case MCSA_LazyReference:
342  // FIXME: This requires -dynamic.
343  Symbol->setNoDeadStrip();
344  if (Symbol->isUndefined())
345  Symbol->setReferenceTypeUndefinedLazy(true);
346  break;
347 
348  // Since .reference sets the no dead strip bit, it is equivalent to
349  // .no_dead_strip in practice.
350  case MCSA_Reference:
351  case MCSA_NoDeadStrip:
352  Symbol->setNoDeadStrip();
353  break;
354 
355  case MCSA_SymbolResolver:
356  Symbol->setSymbolResolver();
357  break;
358 
359  case MCSA_AltEntry:
360  Symbol->setAltEntry();
361  break;
362 
363  case MCSA_PrivateExtern:
364  Symbol->setExternal(true);
365  Symbol->setPrivateExtern(true);
366  break;
367 
368  case MCSA_WeakReference:
369  // FIXME: This requires -dynamic.
370  if (Symbol->isUndefined())
371  Symbol->setWeakReference();
372  break;
373 
374  case MCSA_WeakDefinition:
375  // FIXME: 'as' enforces that this is defined and global. The manual claims
376  // it has to be in a coalesced section, but this isn't enforced.
377  Symbol->setWeakDefinition();
378  break;
379 
381  Symbol->setWeakDefinition();
382  Symbol->setWeakReference();
383  break;
384  }
385 
386  return true;
387 }
388 
389 void MCMachOStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
390  // Encode the 'desc' value into the lowest implementation defined bits.
391  getAssembler().registerSymbol(*Symbol);
392  cast<MCSymbolMachO>(Symbol)->setDesc(DescValue);
393 }
394 
395 void MCMachOStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
396  unsigned ByteAlignment) {
397  // FIXME: Darwin 'as' does appear to allow redef of a .comm by itself.
398  assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
399 
400  getAssembler().registerSymbol(*Symbol);
401  Symbol->setExternal(true);
402  Symbol->setCommon(Size, ByteAlignment);
403 }
404 
405 void MCMachOStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
406  unsigned ByteAlignment) {
407  // '.lcomm' is equivalent to '.zerofill'.
408  return EmitZerofill(getContext().getObjectFileInfo()->getDataBSSSection(),
409  Symbol, Size, ByteAlignment);
410 }
411 
412 void MCMachOStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
413  uint64_t Size, unsigned ByteAlignment) {
414  // On darwin all virtual sections have zerofill type.
415  assert(Section->isVirtualSection() && "Section does not have zerofill type!");
416 
417  PushSection();
418  SwitchSection(Section);
419 
420  // The symbol may not be present, which only creates the section.
421  if (Symbol) {
422  EmitValueToAlignment(ByteAlignment, 0, 1, 0);
423  EmitLabel(Symbol);
424  EmitZeros(Size);
425  }
426  PopSection();
427 }
428 
429 // This should always be called with the thread local bss section. Like the
430 // .zerofill directive this doesn't actually switch sections on us.
431 void MCMachOStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
432  uint64_t Size, unsigned ByteAlignment) {
433  EmitZerofill(Section, Symbol, Size, ByteAlignment);
434 }
435 
436 void MCMachOStreamer::EmitInstToData(const MCInst &Inst,
437  const MCSubtargetInfo &STI) {
438  MCDataFragment *DF = getOrCreateDataFragment();
439 
441  SmallString<256> Code;
442  raw_svector_ostream VecOS(Code);
443  getAssembler().getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
444 
445  // Add the fixups and data.
446  for (MCFixup &Fixup : Fixups) {
447  Fixup.setOffset(Fixup.getOffset() + DF->getContents().size());
448  DF->getFixups().push_back(Fixup);
449  }
450  DF->getContents().append(Code.begin(), Code.end());
451 }
452 
453 void MCMachOStreamer::FinishImpl() {
454  EmitFrames(&getAssembler().getBackend());
455 
456  // We have to set the fragment atom associations so we can relax properly for
457  // Mach-O.
458 
459  // First, scan the symbol table to build a lookup table from fragments to
460  // defining symbols.
462  for (const MCSymbol &Symbol : getAssembler().symbols()) {
463  if (getAssembler().isSymbolLinkerVisible(Symbol) && Symbol.isInSection() &&
464  !Symbol.isVariable()) {
465  // An atom defining symbol should never be internal to a fragment.
466  assert(Symbol.getOffset() == 0 &&
467  "Invalid offset in atom defining symbol!");
468  DefiningSymbolMap[Symbol.getFragment()] = &Symbol;
469  }
470  }
471 
472  // Set the fragment atom associations by tracking the last seen atom defining
473  // symbol.
474  for (MCSection &Sec : getAssembler()) {
475  const MCSymbol *CurrentAtom = nullptr;
476  for (MCFragment &Frag : Sec) {
477  if (const MCSymbol *Symbol = DefiningSymbolMap.lookup(&Frag))
478  CurrentAtom = Symbol;
479  Frag.setAtom(CurrentAtom);
480  }
481  }
482 
484 }
485 
487  std::unique_ptr<MCAsmBackend> &&MAB,
488  raw_pwrite_stream &OS,
489  std::unique_ptr<MCCodeEmitter> &&CE,
490  bool RelaxAll, bool DWARFMustBeAtTheEnd,
491  bool LabelSections) {
492  MCMachOStreamer *S =
493  new MCMachOStreamer(Context, std::move(MAB), OS, std::move(CE),
494  DWARFMustBeAtTheEnd, LabelSections);
495  const Triple &Target = Context.getObjectFileInfo()->getTargetTriple();
496  S->EmitVersionForTarget(Target);
497  if (RelaxAll)
498  S->getAssembler().setRelaxAll(true);
499  return S;
500 }
Instances of this class represent a uniqued identifier for a section in the current translation unit...
Definition: MCSection.h:39
void setPrivateExtern(bool Value)
Definition: MCSymbol.h:395
void setReferenceTypeUndefinedLazy(bool Value) const
Definition: MCSymbolMachO.h:54
This represents a section on a Mach-O system (used by Mac OS X).
LLVMContext & Context
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
bool isVariable() const
isVariable - Check if this is a variable symbol.
Definition: MCSymbol.h:294
.type _foo, STT_OBJECT # aka
Definition: MCDirectives.h:25
This represents an "assembler immediate".
Definition: MCValue.h:40
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:42
Not a valid directive.
Definition: MCDirectives.h:20
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:136
MCStreamer * createMachOStreamer(MCContext &Ctx, std::unique_ptr< MCAsmBackend > &&TAB, raw_pwrite_stream &OS, std::unique_ptr< MCCodeEmitter > &&CE, bool RelaxAll, bool DWARFMustBeAtTheEnd, bool LabelSections=false)
A raw_ostream that writes to an SmallVector or SmallString.
Definition: raw_ostream.h:489
MCDataRegionType
Definition: MCDirectives.h:56
.type _foo, STT_NOTYPE # aka
Definition: MCDirectives.h:28
Encode information on a single operation to perform on a byte sequence (e.g., an encoded instruction)...
Definition: MCFixup.h:66
int64_t getConstant() const
Definition: MCValue.h:47
const MCSymbolRefExpr * getSymB() const
Definition: MCValue.h:49
Definition: BitVector.h:921
void setExternal(bool Value) const
Definition: MCSymbol.h:392
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:42
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:36
bool isInSection() const
isInSection - Check if this symbol is defined in some section (i.e., it is defined but not absolute)...
Definition: MCSymbol.h:252
.data_region jt16
Definition: MCDirectives.h:59
Represent a reference to a symbol from inside an expression.
Definition: MCExpr.h:165
void setCommon(uint64_t Size, unsigned Align)
Mark this symbol as being &#39;common&#39;.
Definition: MCSymbol.h:343
.local (ELF)
Definition: MCDirectives.h:35
StringRef getSectionName() const
.no_dead_strip (MachO)
Definition: MCDirectives.h:36
PlatformType
Definition: MachO.h:484
Context object for machine code objects.
Definition: MCContext.h:63
void setSymbolResolver() const
Definition: MCSymbolMachO.h:89
.code16 (X86) / .code 16 (ARM)
Definition: MCDirectives.h:51
bool evaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout, const MCFixup *Fixup) const
Try to evaluate the expression to a relocatable value, i.e.
Definition: MCExpr.cpp:604
Streaming object file generation interface.
.type _foo, STT_GNU_IFUNC
Definition: MCDirectives.h:24
.alt_entry (MachO)
Definition: MCDirectives.h:38
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:33
.protected (ELF)
Definition: MCDirectives.h:40
.lazy_reference (MachO)
Definition: MCDirectives.h:34
SmallVectorImpl< char > & getContents()
Definition: MCFragment.h:183
.reference (MachO)
Definition: MCDirectives.h:41
StringRef getSegmentName() const
Instances of this class represent a single low-level machine instruction.
Definition: MCInst.h:159
Flag
These should be considered private to the implementation of the MCInstrDesc class.
Definition: MCInstrDesc.h:121
.hidden (ELF)
Definition: MCDirectives.h:31
.data_region jt32
Definition: MCDirectives.h:60
Streaming machine code generation interface.
Definition: MCStreamer.h:183
void setWeakDefinition() const
Definition: MCSymbolMachO.h:82
void EmitLabel(MCSymbol *Symbol, SMLoc Loc=SMLoc()) override
Emit a label for Symbol into the current section.
.weak_def_can_be_hidden (MachO)
Definition: MCDirectives.h:45
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:116
SmallVectorImpl< MCFixup > & getFixups()
Definition: MCFragment.h:208
MCLOHType
Linker Optimization Hint Type.
const MCSymbolRefExpr * getSymA() const
Definition: MCValue.h:48
const MCObjectFileInfo * getObjectFileInfo() const
Definition: MCContext.h:294
.subsections_via_symbols (MachO)
Definition: MCDirectives.h:50
uint64_t getOffset() const
Definition: MCSymbol.h:319
.weak_reference (MachO)
Definition: MCDirectives.h:44
bool isExternal() const
Definition: MCSymbol.h:391
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:44
static bool canGoAfterDWARF(const MCSectionMachO &MSec)
PowerPC TLS Dynamic Call Fixup
virtual bool isVirtualSection() const =0
Check whether this section is "virtual", that is has no actual object file contents.
void setAltEntry() const
Definition: MCSymbolMachO.h:93
bool isUndefined(bool SetUsed=true) const
isUndefined - Check if this symbol undefined (i.e., implicitly defined).
Definition: MCSymbol.h:257
MCFragment * getFragment(bool SetUsed=true) const
Definition: MCSymbol.h:382
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:862
.indirect_symbol (MachO)
Definition: MCDirectives.h:32
.type _foo, STT_TLS # aka
Definition: MCDirectives.h:26
MCSymbol * getBeginSymbol()
Definition: MCSection.h:106
const Triple & getTargetTriple() const
MCSymbolAttr
Definition: MCDirectives.h:19
Target - Wrapper for Target specific information.
.syntax (ARM/ELF)
Definition: MCDirectives.h:49
.internal (ELF)
Definition: MCDirectives.h:33
void append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:396
.code32 (X86) / .code 32 (ARM)
Definition: MCDirectives.h:52
.type _foo, STT_COMMON # aka
Definition: MCDirectives.h:27
.code64 (X86)
Definition: MCDirectives.h:53
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator end()
Definition: SmallVector.h:120
.symbol_resolver (MachO)
Definition: MCDirectives.h:37
.type _foo,
Definition: MCDirectives.h:30
void FinishImpl() override
Streamer specific finalization.
MCAssemblerFlag
Definition: MCDirectives.h:48
.type _foo, STT_FUNC # aka
Definition: MCDirectives.h:23
void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override
Emit an assignment of Value to Symbol.
void reset() override
state management
MCSubtargetInfo - Generic base class for all target subtargets.
void setNoDeadStrip() const
Definition: MCSymbolMachO.h:68
.weak_definition (MachO)
Definition: MCDirectives.h:43
ValueT lookup(const_arg_type_t< KeyT > Val) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: DenseMap.h:181
StringRef getName() const
getName - Get the symbol name.
Definition: MCSymbol.h:203
An abstract base class for streams implementations that also support a pwrite operation.
Definition: raw_ostream.h:337
const unsigned Kind
Fragment for data and encoded instructions.
Definition: MCFragment.h:226
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
.private_extern (MachO)
Definition: MCDirectives.h:39
.data_region jt8
Definition: MCDirectives.h:58
MCVersionMinType
Definition: MCDirectives.h:64
LLVM Value Representation.
Definition: Value.h:73
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
Represents a location in source code.
Definition: SMLoc.h:24
void setWeakReference() const
Definition: MCSymbolMachO.h:75
bool isPrivateExtern() const
Definition: MCSymbol.h:394
constexpr char Args[]
Key for Kernel::Metadata::mArgs.
.end_data_region
Definition: MCDirectives.h:61
void setBeginSymbol(MCSymbol *Sym)
Definition: MCSection.h:110