MCAssembler.h revision c90e30aa6f3792a460202017523171f435e2ba34
1//===- MCAssembler.h - Object File Generation -------------------*- 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#ifndef LLVM_MC_MCASSEMBLER_H
11#define LLVM_MC_MCASSEMBLER_H
12
13#include "llvm/ADT/DenseMap.h"
14#include "llvm/ADT/SmallString.h"
15#include "llvm/ADT/ilist.h"
16#include "llvm/ADT/ilist_node.h"
17#include "llvm/Support/Casting.h"
18#include "llvm/MC/MCFixup.h"
19#include "llvm/MC/MCInst.h"
20#include "llvm/System/DataTypes.h"
21#include <vector> // FIXME: Shouldn't be needed.
22
23namespace llvm {
24class raw_ostream;
25class MCAsmLayout;
26class MCAssembler;
27class MCContext;
28class MCCodeEmitter;
29class MCExpr;
30class MCFragment;
31class MCObjectWriter;
32class MCSection;
33class MCSectionData;
34class MCSymbol;
35class MCSymbolData;
36class MCValue;
37class TargetAsmBackend;
38
39class MCFragment : public ilist_node<MCFragment> {
40  friend class MCAsmLayout;
41
42  MCFragment(const MCFragment&);     // DO NOT IMPLEMENT
43  void operator=(const MCFragment&); // DO NOT IMPLEMENT
44
45public:
46  enum FragmentType {
47    FT_Align,
48    FT_Data,
49    FT_Fill,
50    FT_Inst,
51    FT_Org
52  };
53
54private:
55  FragmentType Kind;
56
57  /// Parent - The data for the section this fragment is in.
58  MCSectionData *Parent;
59
60  /// Atom - The atom this fragment is in, as represented by it's defining
61  /// symbol. Atom's are only used by backends which set
62  /// \see MCAsmBackend::hasReliableSymbolDifference().
63  MCSymbolData *Atom;
64
65  /// @name Assembler Backend Data
66  /// @{
67  //
68  // FIXME: This could all be kept private to the assembler implementation.
69
70  /// Offset - The offset of this fragment in its section. This is ~0 until
71  /// initialized.
72  uint64_t Offset;
73
74  /// EffectiveSize - The compute size of this section. This is ~0 until
75  /// initialized.
76  uint64_t EffectiveSize;
77
78  /// LayoutOrder - The global layout order of this fragment. This is the index
79  /// across all fragments in the file, not just within the section.
80  unsigned LayoutOrder;
81
82  /// @}
83
84protected:
85  MCFragment(FragmentType _Kind, MCSectionData *_Parent = 0);
86
87public:
88  // Only for sentinel.
89  MCFragment();
90
91  FragmentType getKind() const { return Kind; }
92
93  MCSectionData *getParent() const { return Parent; }
94  void setParent(MCSectionData *Value) { Parent = Value; }
95
96  MCSymbolData *getAtom() const { return Atom; }
97  void setAtom(MCSymbolData *Value) { Atom = Value; }
98
99  unsigned getLayoutOrder() const { return LayoutOrder; }
100  void setLayoutOrder(unsigned Value) { LayoutOrder = Value; }
101
102  static bool classof(const MCFragment *O) { return true; }
103
104  void dump();
105};
106
107class MCDataFragment : public MCFragment {
108  SmallString<32> Contents;
109
110  /// Fixups - The list of fixups in this fragment.
111  std::vector<MCFixup> Fixups;
112
113public:
114  typedef std::vector<MCFixup>::const_iterator const_fixup_iterator;
115  typedef std::vector<MCFixup>::iterator fixup_iterator;
116
117public:
118  MCDataFragment(MCSectionData *SD = 0) : MCFragment(FT_Data, SD) {}
119
120  /// @name Accessors
121  /// @{
122
123  SmallString<32> &getContents() { return Contents; }
124  const SmallString<32> &getContents() const { return Contents; }
125
126  /// @}
127  /// @name Fixup Access
128  /// @{
129
130  void addFixup(MCFixup Fixup) {
131    // Enforce invariant that fixups are in offset order.
132    assert((Fixups.empty() || Fixup.getOffset() > Fixups.back().getOffset()) &&
133           "Fixups must be added in order!");
134    Fixups.push_back(Fixup);
135  }
136
137  std::vector<MCFixup> &getFixups() { return Fixups; }
138  const std::vector<MCFixup> &getFixups() const { return Fixups; }
139
140  fixup_iterator fixup_begin() { return Fixups.begin(); }
141  const_fixup_iterator fixup_begin() const { return Fixups.begin(); }
142
143  fixup_iterator fixup_end() {return Fixups.end();}
144  const_fixup_iterator fixup_end() const {return Fixups.end();}
145
146  size_t fixup_size() const { return Fixups.size(); }
147
148  /// @}
149
150  static bool classof(const MCFragment *F) {
151    return F->getKind() == MCFragment::FT_Data;
152  }
153  static bool classof(const MCDataFragment *) { return true; }
154};
155
156// FIXME: This current incarnation of MCInstFragment doesn't make much sense, as
157// it is almost entirely a duplicate of MCDataFragment. If we decide to stick
158// with this approach (as opposed to making MCInstFragment a very light weight
159// object with just the MCInst and a code size, then we should just change
160// MCDataFragment to have an optional MCInst at its end.
161class MCInstFragment : public MCFragment {
162  /// Inst - The instruction this is a fragment for.
163  MCInst Inst;
164
165  /// InstSize - The size of the currently encoded instruction.
166  SmallString<8> Code;
167
168  /// Fixups - The list of fixups in this fragment.
169  SmallVector<MCFixup, 1> Fixups;
170
171public:
172  typedef SmallVectorImpl<MCFixup>::const_iterator const_fixup_iterator;
173  typedef SmallVectorImpl<MCFixup>::iterator fixup_iterator;
174
175public:
176  MCInstFragment(MCInst _Inst, MCSectionData *SD = 0)
177    : MCFragment(FT_Inst, SD), Inst(_Inst) {
178  }
179
180  /// @name Accessors
181  /// @{
182
183  SmallVectorImpl<char> &getCode() { return Code; }
184  const SmallVectorImpl<char> &getCode() const { return Code; }
185
186  unsigned getInstSize() const { return Code.size(); }
187
188  MCInst &getInst() { return Inst; }
189  const MCInst &getInst() const { return Inst; }
190
191  void setInst(MCInst Value) { Inst = Value; }
192
193  /// @}
194  /// @name Fixup Access
195  /// @{
196
197  SmallVectorImpl<MCFixup> &getFixups() { return Fixups; }
198  const SmallVectorImpl<MCFixup> &getFixups() const { return Fixups; }
199
200  fixup_iterator fixup_begin() { return Fixups.begin(); }
201  const_fixup_iterator fixup_begin() const { return Fixups.begin(); }
202
203  fixup_iterator fixup_end() {return Fixups.end();}
204  const_fixup_iterator fixup_end() const {return Fixups.end();}
205
206  size_t fixup_size() const { return Fixups.size(); }
207
208  /// @}
209
210  static bool classof(const MCFragment *F) {
211    return F->getKind() == MCFragment::FT_Inst;
212  }
213  static bool classof(const MCInstFragment *) { return true; }
214};
215
216class MCAlignFragment : public MCFragment {
217  /// Alignment - The alignment to ensure, in bytes.
218  unsigned Alignment;
219
220  /// Value - Value to use for filling padding bytes.
221  int64_t Value;
222
223  /// ValueSize - The size of the integer (in bytes) of \arg Value.
224  unsigned ValueSize;
225
226  /// MaxBytesToEmit - The maximum number of bytes to emit; if the alignment
227  /// cannot be satisfied in this width then this fragment is ignored.
228  unsigned MaxBytesToEmit;
229
230  /// EmitNops - Flag to indicate that (optimal) NOPs should be emitted instead
231  /// of using the provided value. The exact interpretation of this flag is
232  /// target dependent.
233  bool EmitNops : 1;
234
235  /// OnlyAlignAddress - Flag to indicate that this align is only used to adjust
236  /// the address space size of a section and that it should not be included as
237  /// part of the section size. This flag can only be used on the last fragment
238  /// in a section.
239  bool OnlyAlignAddress : 1;
240
241public:
242  MCAlignFragment(unsigned _Alignment, int64_t _Value, unsigned _ValueSize,
243                  unsigned _MaxBytesToEmit, MCSectionData *SD = 0)
244    : MCFragment(FT_Align, SD), Alignment(_Alignment),
245      Value(_Value),ValueSize(_ValueSize),
246      MaxBytesToEmit(_MaxBytesToEmit), EmitNops(false),
247      OnlyAlignAddress(false) {}
248
249  /// @name Accessors
250  /// @{
251
252  unsigned getAlignment() const { return Alignment; }
253
254  int64_t getValue() const { return Value; }
255
256  unsigned getValueSize() const { return ValueSize; }
257
258  unsigned getMaxBytesToEmit() const { return MaxBytesToEmit; }
259
260  bool hasEmitNops() const { return EmitNops; }
261  void setEmitNops(bool Value) { EmitNops = Value; }
262
263  bool hasOnlyAlignAddress() const { return OnlyAlignAddress; }
264  void setOnlyAlignAddress(bool Value) { OnlyAlignAddress = Value; }
265
266  /// @}
267
268  static bool classof(const MCFragment *F) {
269    return F->getKind() == MCFragment::FT_Align;
270  }
271  static bool classof(const MCAlignFragment *) { return true; }
272};
273
274class MCFillFragment : public MCFragment {
275  /// Value - Value to use for filling bytes.
276  int64_t Value;
277
278  /// ValueSize - The size (in bytes) of \arg Value to use when filling, or 0 if
279  /// this is a virtual fill fragment.
280  unsigned ValueSize;
281
282  /// Size - The number of bytes to insert.
283  uint64_t Size;
284
285public:
286  MCFillFragment(int64_t _Value, unsigned _ValueSize, uint64_t _Size,
287                 MCSectionData *SD = 0)
288    : MCFragment(FT_Fill, SD),
289      Value(_Value), ValueSize(_ValueSize), Size(_Size) {
290    assert((!ValueSize || (Size % ValueSize) == 0) &&
291           "Fill size must be a multiple of the value size!");
292  }
293
294  /// @name Accessors
295  /// @{
296
297  int64_t getValue() const { return Value; }
298
299  unsigned getValueSize() const { return ValueSize; }
300
301  uint64_t getSize() const { return Size; }
302
303  /// @}
304
305  static bool classof(const MCFragment *F) {
306    return F->getKind() == MCFragment::FT_Fill;
307  }
308  static bool classof(const MCFillFragment *) { return true; }
309};
310
311class MCOrgFragment : public MCFragment {
312  /// Offset - The offset this fragment should start at.
313  const MCExpr *Offset;
314
315  /// Value - Value to use for filling bytes.
316  int8_t Value;
317
318public:
319  MCOrgFragment(const MCExpr &_Offset, int8_t _Value, MCSectionData *SD = 0)
320    : MCFragment(FT_Org, SD),
321      Offset(&_Offset), Value(_Value) {}
322
323  /// @name Accessors
324  /// @{
325
326  const MCExpr &getOffset() const { return *Offset; }
327
328  uint8_t getValue() const { return Value; }
329
330  /// @}
331
332  static bool classof(const MCFragment *F) {
333    return F->getKind() == MCFragment::FT_Org;
334  }
335  static bool classof(const MCOrgFragment *) { return true; }
336};
337
338// FIXME: Should this be a separate class, or just merged into MCSection? Since
339// we anticipate the fast path being through an MCAssembler, the only reason to
340// keep it out is for API abstraction.
341class MCSectionData : public ilist_node<MCSectionData> {
342  friend class MCAsmLayout;
343
344  MCSectionData(const MCSectionData&);  // DO NOT IMPLEMENT
345  void operator=(const MCSectionData&); // DO NOT IMPLEMENT
346
347public:
348  typedef iplist<MCFragment> FragmentListType;
349
350  typedef FragmentListType::const_iterator const_iterator;
351  typedef FragmentListType::iterator iterator;
352
353  typedef FragmentListType::const_reverse_iterator const_reverse_iterator;
354  typedef FragmentListType::reverse_iterator reverse_iterator;
355
356private:
357  iplist<MCFragment> Fragments;
358  const MCSection *Section;
359
360  /// Ordinal - The section index in the assemblers section list.
361  unsigned Ordinal;
362
363  /// LayoutOrder - The index of this section in the layout order.
364  unsigned LayoutOrder;
365
366  /// Alignment - The maximum alignment seen in this section.
367  unsigned Alignment;
368
369  /// @name Assembler Backend Data
370  /// @{
371  //
372  // FIXME: This could all be kept private to the assembler implementation.
373
374  /// Address - The computed address of this section. This is ~0 until
375  /// initialized.
376  uint64_t Address;
377
378  /// HasInstructions - Whether this section has had instructions emitted into
379  /// it.
380  unsigned HasInstructions : 1;
381
382  /// @}
383
384public:
385  // Only for use as sentinel.
386  MCSectionData();
387  MCSectionData(const MCSection &Section, MCAssembler *A = 0);
388
389  const MCSection &getSection() const { return *Section; }
390
391  unsigned getAlignment() const { return Alignment; }
392  void setAlignment(unsigned Value) { Alignment = Value; }
393
394  bool hasInstructions() const { return HasInstructions; }
395  void setHasInstructions(bool Value) { HasInstructions = Value; }
396
397  unsigned getOrdinal() const { return Ordinal; }
398  void setOrdinal(unsigned Value) { Ordinal = Value; }
399
400  unsigned getLayoutOrder() const { return LayoutOrder; }
401  void setLayoutOrder(unsigned Value) { LayoutOrder = Value; }
402
403  /// @name Fragment Access
404  /// @{
405
406  const FragmentListType &getFragmentList() const { return Fragments; }
407  FragmentListType &getFragmentList() { return Fragments; }
408
409  iterator begin() { return Fragments.begin(); }
410  const_iterator begin() const { return Fragments.begin(); }
411
412  iterator end() { return Fragments.end(); }
413  const_iterator end() const { return Fragments.end(); }
414
415  reverse_iterator rbegin() { return Fragments.rbegin(); }
416  const_reverse_iterator rbegin() const { return Fragments.rbegin(); }
417
418  reverse_iterator rend() { return Fragments.rend(); }
419  const_reverse_iterator rend() const { return Fragments.rend(); }
420
421  size_t size() const { return Fragments.size(); }
422
423  bool empty() const { return Fragments.empty(); }
424
425  void dump();
426
427  /// @}
428};
429
430// FIXME: Same concerns as with SectionData.
431class MCSymbolData : public ilist_node<MCSymbolData> {
432public:
433  const MCSymbol *Symbol;
434
435  /// Fragment - The fragment this symbol's value is relative to, if any.
436  MCFragment *Fragment;
437
438  /// Offset - The offset to apply to the fragment address to form this symbol's
439  /// value.
440  uint64_t Offset;
441
442  /// IsExternal - True if this symbol is visible outside this translation
443  /// unit.
444  unsigned IsExternal : 1;
445
446  /// IsPrivateExtern - True if this symbol is private extern.
447  unsigned IsPrivateExtern : 1;
448
449  /// CommonSize - The size of the symbol, if it is 'common', or 0.
450  //
451  // FIXME: Pack this in with other fields? We could put it in offset, since a
452  // common symbol can never get a definition.
453  uint64_t CommonSize;
454
455  /// CommonAlign - The alignment of the symbol, if it is 'common'.
456  //
457  // FIXME: Pack this in with other fields?
458  unsigned CommonAlign;
459
460  /// Flags - The Flags field is used by object file implementations to store
461  /// additional per symbol information which is not easily classified.
462  uint32_t Flags;
463
464  /// Index - Index field, for use by the object file implementation.
465  uint64_t Index;
466
467public:
468  // Only for use as sentinel.
469  MCSymbolData();
470  MCSymbolData(const MCSymbol &_Symbol, MCFragment *_Fragment, uint64_t _Offset,
471               MCAssembler *A = 0);
472
473  /// @name Accessors
474  /// @{
475
476  const MCSymbol &getSymbol() const { return *Symbol; }
477
478  MCFragment *getFragment() const { return Fragment; }
479  void setFragment(MCFragment *Value) { Fragment = Value; }
480
481  uint64_t getOffset() const { return Offset; }
482  void setOffset(uint64_t Value) { Offset = Value; }
483
484  /// @}
485  /// @name Symbol Attributes
486  /// @{
487
488  bool isExternal() const { return IsExternal; }
489  void setExternal(bool Value) { IsExternal = Value; }
490
491  bool isPrivateExtern() const { return IsPrivateExtern; }
492  void setPrivateExtern(bool Value) { IsPrivateExtern = Value; }
493
494  /// isCommon - Is this a 'common' symbol.
495  bool isCommon() const { return CommonSize != 0; }
496
497  /// setCommon - Mark this symbol as being 'common'.
498  ///
499  /// \param Size - The size of the symbol.
500  /// \param Align - The alignment of the symbol.
501  void setCommon(uint64_t Size, unsigned Align) {
502    CommonSize = Size;
503    CommonAlign = Align;
504  }
505
506  /// getCommonSize - Return the size of a 'common' symbol.
507  uint64_t getCommonSize() const {
508    assert(isCommon() && "Not a 'common' symbol!");
509    return CommonSize;
510  }
511
512  /// getCommonAlignment - Return the alignment of a 'common' symbol.
513  unsigned getCommonAlignment() const {
514    assert(isCommon() && "Not a 'common' symbol!");
515    return CommonAlign;
516  }
517
518  /// getFlags - Get the (implementation defined) symbol flags.
519  uint32_t getFlags() const { return Flags; }
520
521  /// setFlags - Set the (implementation defined) symbol flags.
522  void setFlags(uint32_t Value) { Flags = Value; }
523
524  /// modifyFlags - Modify the flags via a mask
525  void modifyFlags(uint32_t Value, uint32_t Mask) {
526    Flags = (Flags & ~Mask) | Value;
527  }
528
529  /// getIndex - Get the (implementation defined) index.
530  uint64_t getIndex() const { return Index; }
531
532  /// setIndex - Set the (implementation defined) index.
533  void setIndex(uint64_t Value) { Index = Value; }
534
535  /// @}
536
537  void dump();
538};
539
540// FIXME: This really doesn't belong here. See comments below.
541struct IndirectSymbolData {
542  MCSymbol *Symbol;
543  MCSectionData *SectionData;
544};
545
546class MCAssembler {
547  friend class MCAsmLayout;
548
549public:
550  typedef iplist<MCSectionData> SectionDataListType;
551  typedef iplist<MCSymbolData> SymbolDataListType;
552
553  typedef SectionDataListType::const_iterator const_iterator;
554  typedef SectionDataListType::iterator iterator;
555
556  typedef SymbolDataListType::const_iterator const_symbol_iterator;
557  typedef SymbolDataListType::iterator symbol_iterator;
558
559  typedef std::vector<IndirectSymbolData>::const_iterator
560    const_indirect_symbol_iterator;
561  typedef std::vector<IndirectSymbolData>::iterator indirect_symbol_iterator;
562
563private:
564  MCAssembler(const MCAssembler&);    // DO NOT IMPLEMENT
565  void operator=(const MCAssembler&); // DO NOT IMPLEMENT
566
567  MCContext &Context;
568
569  TargetAsmBackend &Backend;
570
571  MCCodeEmitter &Emitter;
572
573  raw_ostream &OS;
574
575  iplist<MCSectionData> Sections;
576
577  iplist<MCSymbolData> Symbols;
578
579  /// The map of sections to their associated assembler backend data.
580  //
581  // FIXME: Avoid this indirection?
582  DenseMap<const MCSection*, MCSectionData*> SectionMap;
583
584  /// The map of symbols to their associated assembler backend data.
585  //
586  // FIXME: Avoid this indirection?
587  DenseMap<const MCSymbol*, MCSymbolData*> SymbolMap;
588
589  std::vector<IndirectSymbolData> IndirectSymbols;
590
591  unsigned RelaxAll : 1;
592  unsigned SubsectionsViaSymbols : 1;
593
594private:
595  /// Evaluate a fixup to a relocatable expression and the value which should be
596  /// placed into the fixup.
597  ///
598  /// \param Layout The layout to use for evaluation.
599  /// \param Fixup The fixup to evaluate.
600  /// \param DF The fragment the fixup is inside.
601  /// \param Target [out] On return, the relocatable expression the fixup
602  /// evaluates to.
603  /// \param Value [out] On return, the value of the fixup as currently layed
604  /// out.
605  /// \return Whether the fixup value was fully resolved. This is true if the
606  /// \arg Value result is fixed, otherwise the value may change due to
607  /// relocation.
608  bool EvaluateFixup(const MCAsmLayout &Layout,
609                     const MCFixup &Fixup, const MCFragment *DF,
610                     MCValue &Target, uint64_t &Value) const;
611
612  /// Check whether a fixup can be satisfied, or whether it needs to be relaxed
613  /// (increased in size, in order to hold its value correctly).
614  bool FixupNeedsRelaxation(const MCFixup &Fixup, const MCFragment *DF,
615                            const MCAsmLayout &Layout) const;
616
617  /// Check whether the given fragment needs relaxation.
618  bool FragmentNeedsRelaxation(const MCInstFragment *IF,
619                               const MCAsmLayout &Layout) const;
620
621  /// Compute the effective fragment size assuming it is layed out at the given
622  /// \arg SectionAddress and \arg FragmentOffset.
623  uint64_t ComputeFragmentSize(MCAsmLayout &Layout, const MCFragment &F,
624                               uint64_t SectionAddress,
625                               uint64_t FragmentOffset) const;
626
627  /// LayoutOnce - Perform one layout iteration and return true if any offsets
628  /// were adjusted.
629  bool LayoutOnce(MCAsmLayout &Layout);
630
631  /// FinishLayout - Finalize a layout, including fragment lowering.
632  void FinishLayout(MCAsmLayout &Layout);
633
634public:
635  /// Find the symbol which defines the atom containing the given symbol, or
636  /// null if there is no such symbol.
637  const MCSymbolData *getAtom(const MCAsmLayout &Layout,
638                              const MCSymbolData *Symbol) const;
639
640  /// Check whether a particular symbol is visible to the linker and is required
641  /// in the symbol table, or whether it can be discarded by the assembler. This
642  /// also effects whether the assembler treats the label as potentially
643  /// defining a separate atom.
644  bool isSymbolLinkerVisible(const MCSymbolData *SD) const;
645
646  /// Emit the section contents using the given object writer.
647  //
648  // FIXME: Should MCAssembler always have a reference to the object writer?
649  void WriteSectionData(const MCSectionData *Section, const MCAsmLayout &Layout,
650                        MCObjectWriter *OW) const;
651
652public:
653  /// Construct a new assembler instance.
654  ///
655  /// \arg OS - The stream to output to.
656  //
657  // FIXME: How are we going to parameterize this? Two obvious options are stay
658  // concrete and require clients to pass in a target like object. The other
659  // option is to make this abstract, and have targets provide concrete
660  // implementations as we do with AsmParser.
661  MCAssembler(MCContext &_Context, TargetAsmBackend &_Backend,
662              MCCodeEmitter &_Emitter, raw_ostream &OS);
663  ~MCAssembler();
664
665  MCContext &getContext() const { return Context; }
666
667  TargetAsmBackend &getBackend() const { return Backend; }
668
669  MCCodeEmitter &getEmitter() const { return Emitter; }
670
671  /// Finish - Do final processing and write the object to the output stream.
672  void Finish();
673
674  // FIXME: This does not belong here.
675  bool getSubsectionsViaSymbols() const {
676    return SubsectionsViaSymbols;
677  }
678  void setSubsectionsViaSymbols(bool Value) {
679    SubsectionsViaSymbols = Value;
680  }
681
682  bool getRelaxAll() const { return RelaxAll; }
683  void setRelaxAll(bool Value) { RelaxAll = Value; }
684
685  /// @name Section List Access
686  /// @{
687
688  const SectionDataListType &getSectionList() const { return Sections; }
689  SectionDataListType &getSectionList() { return Sections; }
690
691  iterator begin() { return Sections.begin(); }
692  const_iterator begin() const { return Sections.begin(); }
693
694  iterator end() { return Sections.end(); }
695  const_iterator end() const { return Sections.end(); }
696
697  size_t size() const { return Sections.size(); }
698
699  /// @}
700  /// @name Symbol List Access
701  /// @{
702
703  const SymbolDataListType &getSymbolList() const { return Symbols; }
704  SymbolDataListType &getSymbolList() { return Symbols; }
705
706  symbol_iterator symbol_begin() { return Symbols.begin(); }
707  const_symbol_iterator symbol_begin() const { return Symbols.begin(); }
708
709  symbol_iterator symbol_end() { return Symbols.end(); }
710  const_symbol_iterator symbol_end() const { return Symbols.end(); }
711
712  size_t symbol_size() const { return Symbols.size(); }
713
714  /// @}
715  /// @name Indirect Symbol List Access
716  /// @{
717
718  // FIXME: This is a total hack, this should not be here. Once things are
719  // factored so that the streamer has direct access to the .o writer, it can
720  // disappear.
721  std::vector<IndirectSymbolData> &getIndirectSymbols() {
722    return IndirectSymbols;
723  }
724
725  indirect_symbol_iterator indirect_symbol_begin() {
726    return IndirectSymbols.begin();
727  }
728  const_indirect_symbol_iterator indirect_symbol_begin() const {
729    return IndirectSymbols.begin();
730  }
731
732  indirect_symbol_iterator indirect_symbol_end() {
733    return IndirectSymbols.end();
734  }
735  const_indirect_symbol_iterator indirect_symbol_end() const {
736    return IndirectSymbols.end();
737  }
738
739  size_t indirect_symbol_size() const { return IndirectSymbols.size(); }
740
741  /// @}
742  /// @name Backend Data Access
743  /// @{
744
745  MCSectionData &getSectionData(const MCSection &Section) const {
746    MCSectionData *Entry = SectionMap.lookup(&Section);
747    assert(Entry && "Missing section data!");
748    return *Entry;
749  }
750
751  MCSectionData &getOrCreateSectionData(const MCSection &Section,
752                                        bool *Created = 0) {
753    MCSectionData *&Entry = SectionMap[&Section];
754
755    if (Created) *Created = !Entry;
756    if (!Entry)
757      Entry = new MCSectionData(Section, this);
758
759    return *Entry;
760  }
761
762  MCSymbolData &getSymbolData(const MCSymbol &Symbol) const {
763    MCSymbolData *Entry = SymbolMap.lookup(&Symbol);
764    assert(Entry && "Missing symbol data!");
765    return *Entry;
766  }
767
768  MCSymbolData &getOrCreateSymbolData(const MCSymbol &Symbol,
769                                      bool *Created = 0) {
770    MCSymbolData *&Entry = SymbolMap[&Symbol];
771
772    if (Created) *Created = !Entry;
773    if (!Entry)
774      Entry = new MCSymbolData(Symbol, 0, 0, this);
775
776    return *Entry;
777  }
778
779  /// @}
780
781  void dump();
782};
783
784} // end namespace llvm
785
786#endif
787