MCAsmStreamer.cpp revision ec0b428398c5fb91fdce5d3d003ab0e4b75b5d6a 
1//===- lib/MC/MCAsmStreamer.cpp - Text Assembly Output --------------------===//
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/MC/MCStreamer.h"
11#include "llvm/MC/MCAsmInfo.h"
12#include "llvm/MC/MCCodeEmitter.h"
13#include "llvm/MC/MCContext.h"
14#include "llvm/MC/MCExpr.h"
15#include "llvm/MC/MCInst.h"
16#include "llvm/MC/MCInstPrinter.h"
17#include "llvm/MC/MCSectionMachO.h"
18#include "llvm/MC/MCSymbol.h"
19#include "llvm/ADT/OwningPtr.h"
20#include "llvm/ADT/SmallString.h"
21#include "llvm/ADT/Twine.h"
22#include "llvm/Support/ErrorHandling.h"
23#include "llvm/Support/MathExtras.h"
24#include "llvm/Support/Format.h"
25#include "llvm/Support/FormattedStream.h"
26#include "llvm/Target/TargetLoweringObjectFile.h"
27using namespace llvm;
28
29namespace {
30
31class MCAsmStreamer : public MCStreamer {
32  formatted_raw_ostream &OS;
33  const MCAsmInfo &MAI;
34  OwningPtr<MCInstPrinter> InstPrinter;
35  OwningPtr<MCCodeEmitter> Emitter;
36
37  SmallString<128> CommentToEmit;
38  raw_svector_ostream CommentStream;
39
40  const TargetLoweringObjectFile *TLOF;
41  int PointerSize;
42
43  unsigned IsLittleEndian : 1;
44  unsigned IsVerboseAsm : 1;
45  unsigned ShowInst : 1;
46
47public:
48  MCAsmStreamer(MCContext &Context, formatted_raw_ostream &os,
49                bool isLittleEndian, bool isVerboseAsm,
50                const TargetLoweringObjectFile *tlof, int pointerSize,
51                MCInstPrinter *printer, MCCodeEmitter *emitter, bool showInst)
52    : MCStreamer(Context), OS(os), MAI(Context.getAsmInfo()),
53      InstPrinter(printer), Emitter(emitter), CommentStream(CommentToEmit),
54      TLOF(tlof), PointerSize(pointerSize),
55      IsLittleEndian(isLittleEndian), IsVerboseAsm(isVerboseAsm),
56      ShowInst(showInst) {
57    if (InstPrinter && IsVerboseAsm)
58      InstPrinter->setCommentStream(CommentStream);
59  }
60  ~MCAsmStreamer() {}
61
62  bool isLittleEndian() const { return IsLittleEndian; }
63
64  inline void EmitEOL() {
65    // If we don't have any comments, just emit a \n.
66    if (!IsVerboseAsm) {
67      OS << '\n';
68      return;
69    }
70    EmitCommentsAndEOL();
71  }
72  void EmitCommentsAndEOL();
73
74  /// isVerboseAsm - Return true if this streamer supports verbose assembly at
75  /// all.
76  virtual bool isVerboseAsm() const { return IsVerboseAsm; }
77
78  /// hasRawTextSupport - We support EmitRawText.
79  virtual bool hasRawTextSupport() const { return true; }
80
81  /// AddComment - Add a comment that can be emitted to the generated .s
82  /// file if applicable as a QoI issue to make the output of the compiler
83  /// more readable.  This only affects the MCAsmStreamer, and only when
84  /// verbose assembly output is enabled.
85  virtual void AddComment(const Twine &T);
86
87  /// AddEncodingComment - Add a comment showing the encoding of an instruction.
88  virtual void AddEncodingComment(const MCInst &Inst);
89
90  /// GetCommentOS - Return a raw_ostream that comments can be written to.
91  /// Unlike AddComment, you are required to terminate comments with \n if you
92  /// use this method.
93  virtual raw_ostream &GetCommentOS() {
94    if (!IsVerboseAsm)
95      return nulls();  // Discard comments unless in verbose asm mode.
96    return CommentStream;
97  }
98
99  /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
100  virtual void AddBlankLine() {
101    EmitEOL();
102  }
103
104  /// @name MCStreamer Interface
105  /// @{
106
107  virtual void SwitchSection(const MCSection *Section);
108
109  virtual void InitSections() {
110    // FIXME, this is MachO specific, but the testsuite
111    // expects this.
112    SwitchSection(getContext().getMachOSection("__TEXT", "__text",
113                         MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
114                         0, SectionKind::getText()));
115  }
116
117  virtual void EmitLabel(MCSymbol *Symbol);
118
119  virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
120  virtual void EmitThumbFunc(MCSymbol *Func);
121
122  virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
123  virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
124
125  virtual void EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute);
126
127  virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
128  virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
129  virtual void EmitCOFFSymbolStorageClass(int StorageClass);
130  virtual void EmitCOFFSymbolType(int Type);
131  virtual void EndCOFFSymbolDef();
132  virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value);
133  virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
134                                unsigned ByteAlignment);
135
136  /// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol.
137  ///
138  /// @param Symbol - The common symbol to emit.
139  /// @param Size - The size of the common symbol.
140  virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size);
141
142  virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
143                            unsigned Size = 0, unsigned ByteAlignment = 0);
144
145  virtual void EmitTBSSSymbol (const MCSection *Section, MCSymbol *Symbol,
146                               uint64_t Size, unsigned ByteAlignment = 0);
147
148  virtual void EmitBytes(StringRef Data, unsigned AddrSpace);
149
150  virtual void EmitValue(const MCExpr *Value, unsigned Size,unsigned AddrSpace);
151
152  virtual void EmitULEB128Value(const MCExpr *Value, unsigned AddrSpace = 0);
153
154  virtual void EmitSLEB128Value(const MCExpr *Value, unsigned AddrSpace = 0);
155
156  virtual void EmitGPRel32Value(const MCExpr *Value);
157
158
159  virtual void EmitFill(uint64_t NumBytes, uint8_t FillValue,
160                        unsigned AddrSpace);
161
162  virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
163                                    unsigned ValueSize = 1,
164                                    unsigned MaxBytesToEmit = 0);
165
166  virtual void EmitCodeAlignment(unsigned ByteAlignment,
167                                 unsigned MaxBytesToEmit = 0);
168
169  virtual void EmitValueToOffset(const MCExpr *Offset,
170                                 unsigned char Value = 0);
171
172  virtual void EmitFileDirective(StringRef Filename);
173  virtual bool EmitDwarfFileDirective(unsigned FileNo, StringRef Filename);
174  virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
175                                     unsigned Column, unsigned Flags,
176                                     unsigned Isa, unsigned Discriminator);
177
178  virtual bool EmitCFIStartProc();
179  virtual bool EmitCFIEndProc();
180  virtual bool EmitCFIDefCfaOffset(int64_t Offset);
181  virtual bool EmitCFIDefCfaRegister(int64_t Register);
182  virtual bool EmitCFIOffset(int64_t Register, int64_t Offset);
183  virtual bool EmitCFIPersonality(const MCSymbol *Sym);
184  virtual bool EmitCFILsda(const MCSymbol *Sym);
185
186  virtual void EmitInstruction(const MCInst &Inst);
187
188  /// EmitRawText - If this file is backed by an assembly streamer, this dumps
189  /// the specified string in the output .s file.  This capability is
190  /// indicated by the hasRawTextSupport() predicate.
191  virtual void EmitRawText(StringRef String);
192
193  virtual void Finish();
194
195  /// @}
196};
197
198} // end anonymous namespace.
199
200/// AddComment - Add a comment that can be emitted to the generated .s
201/// file if applicable as a QoI issue to make the output of the compiler
202/// more readable.  This only affects the MCAsmStreamer, and only when
203/// verbose assembly output is enabled.
204void MCAsmStreamer::AddComment(const Twine &T) {
205  if (!IsVerboseAsm) return;
206
207  // Make sure that CommentStream is flushed.
208  CommentStream.flush();
209
210  T.toVector(CommentToEmit);
211  // Each comment goes on its own line.
212  CommentToEmit.push_back('\n');
213
214  // Tell the comment stream that the vector changed underneath it.
215  CommentStream.resync();
216}
217
218void MCAsmStreamer::EmitCommentsAndEOL() {
219  if (CommentToEmit.empty() && CommentStream.GetNumBytesInBuffer() == 0) {
220    OS << '\n';
221    return;
222  }
223
224  CommentStream.flush();
225  StringRef Comments = CommentToEmit.str();
226
227  assert(Comments.back() == '\n' &&
228         "Comment array not newline terminated");
229  do {
230    // Emit a line of comments.
231    OS.PadToColumn(MAI.getCommentColumn());
232    size_t Position = Comments.find('\n');
233    OS << MAI.getCommentString() << ' ' << Comments.substr(0, Position) << '\n';
234
235    Comments = Comments.substr(Position+1);
236  } while (!Comments.empty());
237
238  CommentToEmit.clear();
239  // Tell the comment stream that the vector changed underneath it.
240  CommentStream.resync();
241}
242
243static inline int64_t truncateToSize(int64_t Value, unsigned Bytes) {
244  assert(Bytes && "Invalid size!");
245  return Value & ((uint64_t) (int64_t) -1 >> (64 - Bytes * 8));
246}
247
248void MCAsmStreamer::SwitchSection(const MCSection *Section) {
249  assert(Section && "Cannot switch to a null section!");
250  if (Section != CurSection) {
251    PrevSection = CurSection;
252    CurSection = Section;
253    Section->PrintSwitchToSection(MAI, OS);
254  }
255}
256
257void MCAsmStreamer::EmitLabel(MCSymbol *Symbol) {
258  assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
259  assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
260  assert(CurSection && "Cannot emit before setting section!");
261
262  OS << *Symbol << MAI.getLabelSuffix();
263  EmitEOL();
264  Symbol->setSection(*CurSection);
265}
266
267void MCAsmStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
268  switch (Flag) {
269  default: assert(0 && "Invalid flag!");
270  case MCAF_SyntaxUnified:         OS << "\t.syntax unified"; break;
271  case MCAF_SubsectionsViaSymbols: OS << ".subsections_via_symbols"; break;
272  case MCAF_Code16:                OS << "\t.code\t16"; break;
273  case MCAF_Code32:                OS << "\t.code\t32"; break;
274  }
275  EmitEOL();
276}
277
278void MCAsmStreamer::EmitThumbFunc(MCSymbol *Func) {
279  // This needs to emit to a temporary string to get properly quoted
280  // MCSymbols when they have spaces in them.
281  OS << "\t.thumb_func";
282  if (Func)
283    OS << '\t' << *Func;
284  EmitEOL();
285}
286
287void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
288  OS << *Symbol << " = " << *Value;
289  EmitEOL();
290
291  // FIXME: Lift context changes into super class.
292  Symbol->setVariableValue(Value);
293}
294
295void MCAsmStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
296  OS << ".weakref " << *Alias << ", " << *Symbol;
297  EmitEOL();
298}
299
300void MCAsmStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
301                                        MCSymbolAttr Attribute) {
302  switch (Attribute) {
303  case MCSA_Invalid: assert(0 && "Invalid symbol attribute");
304  case MCSA_ELF_TypeFunction:    /// .type _foo, STT_FUNC  # aka @function
305  case MCSA_ELF_TypeIndFunction: /// .type _foo, STT_GNU_IFUNC
306  case MCSA_ELF_TypeObject:      /// .type _foo, STT_OBJECT  # aka @object
307  case MCSA_ELF_TypeTLS:         /// .type _foo, STT_TLS     # aka @tls_object
308  case MCSA_ELF_TypeCommon:      /// .type _foo, STT_COMMON  # aka @common
309  case MCSA_ELF_TypeNoType:      /// .type _foo, STT_NOTYPE  # aka @notype
310  case MCSA_ELF_TypeGnuUniqueObject:  /// .type _foo, @gnu_unique_object
311    assert(MAI.hasDotTypeDotSizeDirective() && "Symbol Attr not supported");
312    OS << "\t.type\t" << *Symbol << ','
313       << ((MAI.getCommentString()[0] != '@') ? '@' : '%');
314    switch (Attribute) {
315    default: assert(0 && "Unknown ELF .type");
316    case MCSA_ELF_TypeFunction:    OS << "function"; break;
317    case MCSA_ELF_TypeIndFunction: OS << "gnu_indirect_function"; break;
318    case MCSA_ELF_TypeObject:      OS << "object"; break;
319    case MCSA_ELF_TypeTLS:         OS << "tls_object"; break;
320    case MCSA_ELF_TypeCommon:      OS << "common"; break;
321    case MCSA_ELF_TypeNoType:      OS << "no_type"; break;
322    case MCSA_ELF_TypeGnuUniqueObject: OS << "gnu_unique_object"; break;
323    }
324    EmitEOL();
325    return;
326  case MCSA_Global: // .globl/.global
327    OS << MAI.getGlobalDirective();
328    break;
329  case MCSA_Hidden:         OS << "\t.hidden\t";          break;
330  case MCSA_IndirectSymbol: OS << "\t.indirect_symbol\t"; break;
331  case MCSA_Internal:       OS << "\t.internal\t";        break;
332  case MCSA_LazyReference:  OS << "\t.lazy_reference\t";  break;
333  case MCSA_Local:          OS << "\t.local\t";           break;
334  case MCSA_NoDeadStrip:    OS << "\t.no_dead_strip\t";   break;
335  case MCSA_SymbolResolver: OS << "\t.symbol_resolver\t"; break;
336  case MCSA_PrivateExtern:  OS << "\t.private_extern\t";  break;
337  case MCSA_Protected:      OS << "\t.protected\t";       break;
338  case MCSA_Reference:      OS << "\t.reference\t";       break;
339  case MCSA_Weak:           OS << "\t.weak\t";            break;
340  case MCSA_WeakDefinition: OS << "\t.weak_definition\t"; break;
341      // .weak_reference
342  case MCSA_WeakReference:  OS << MAI.getWeakRefDirective(); break;
343  case MCSA_WeakDefAutoPrivate: OS << "\t.weak_def_can_be_hidden\t"; break;
344  }
345
346  OS << *Symbol;
347  EmitEOL();
348}
349
350void MCAsmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
351  OS << ".desc" << ' ' << *Symbol << ',' << DescValue;
352  EmitEOL();
353}
354
355void MCAsmStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {
356  OS << "\t.def\t " << *Symbol << ';';
357  EmitEOL();
358}
359
360void MCAsmStreamer::EmitCOFFSymbolStorageClass (int StorageClass) {
361  OS << "\t.scl\t" << StorageClass << ';';
362  EmitEOL();
363}
364
365void MCAsmStreamer::EmitCOFFSymbolType (int Type) {
366  OS << "\t.type\t" << Type << ';';
367  EmitEOL();
368}
369
370void MCAsmStreamer::EndCOFFSymbolDef() {
371  OS << "\t.endef";
372  EmitEOL();
373}
374
375void MCAsmStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
376  assert(MAI.hasDotTypeDotSizeDirective());
377  OS << "\t.size\t" << *Symbol << ", " << *Value << '\n';
378}
379
380void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
381                                     unsigned ByteAlignment) {
382  OS << "\t.comm\t" << *Symbol << ',' << Size;
383  if (ByteAlignment != 0) {
384    if (MAI.getCOMMDirectiveAlignmentIsInBytes())
385      OS << ',' << ByteAlignment;
386    else
387      OS << ',' << Log2_32(ByteAlignment);
388  }
389  EmitEOL();
390}
391
392/// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol.
393///
394/// @param Symbol - The common symbol to emit.
395/// @param Size - The size of the common symbol.
396void MCAsmStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size) {
397  assert(MAI.hasLCOMMDirective() && "Doesn't have .lcomm, can't emit it!");
398  OS << "\t.lcomm\t" << *Symbol << ',' << Size;
399  EmitEOL();
400}
401
402void MCAsmStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
403                                 unsigned Size, unsigned ByteAlignment) {
404  // Note: a .zerofill directive does not switch sections.
405  OS << ".zerofill ";
406
407  // This is a mach-o specific directive.
408  const MCSectionMachO *MOSection = ((const MCSectionMachO*)Section);
409  OS << MOSection->getSegmentName() << "," << MOSection->getSectionName();
410
411  if (Symbol != NULL) {
412    OS << ',' << *Symbol << ',' << Size;
413    if (ByteAlignment != 0)
414      OS << ',' << Log2_32(ByteAlignment);
415  }
416  EmitEOL();
417}
418
419// .tbss sym, size, align
420// This depends that the symbol has already been mangled from the original,
421// e.g. _a.
422void MCAsmStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
423                                   uint64_t Size, unsigned ByteAlignment) {
424  assert(Symbol != NULL && "Symbol shouldn't be NULL!");
425  // Instead of using the Section we'll just use the shortcut.
426  // This is a mach-o specific directive and section.
427  OS << ".tbss " << *Symbol << ", " << Size;
428
429  // Output align if we have it.  We default to 1 so don't bother printing
430  // that.
431  if (ByteAlignment > 1) OS << ", " << Log2_32(ByteAlignment);
432
433  EmitEOL();
434}
435
436static inline char toOctal(int X) { return (X&7)+'0'; }
437
438static void PrintQuotedString(StringRef Data, raw_ostream &OS) {
439  OS << '"';
440
441  for (unsigned i = 0, e = Data.size(); i != e; ++i) {
442    unsigned char C = Data[i];
443    if (C == '"' || C == '\\') {
444      OS << '\\' << (char)C;
445      continue;
446    }
447
448    if (isprint((unsigned char)C)) {
449      OS << (char)C;
450      continue;
451    }
452
453    switch (C) {
454      case '\b': OS << "\\b"; break;
455      case '\f': OS << "\\f"; break;
456      case '\n': OS << "\\n"; break;
457      case '\r': OS << "\\r"; break;
458      case '\t': OS << "\\t"; break;
459      default:
460        OS << '\\';
461        OS << toOctal(C >> 6);
462        OS << toOctal(C >> 3);
463        OS << toOctal(C >> 0);
464        break;
465    }
466  }
467
468  OS << '"';
469}
470
471
472void MCAsmStreamer::EmitBytes(StringRef Data, unsigned AddrSpace) {
473  assert(CurSection && "Cannot emit contents before setting section!");
474  if (Data.empty()) return;
475
476  if (Data.size() == 1) {
477    OS << MAI.getData8bitsDirective(AddrSpace);
478    OS << (unsigned)(unsigned char)Data[0];
479    EmitEOL();
480    return;
481  }
482
483  // If the data ends with 0 and the target supports .asciz, use it, otherwise
484  // use .ascii
485  if (MAI.getAscizDirective() && Data.back() == 0) {
486    OS << MAI.getAscizDirective();
487    Data = Data.substr(0, Data.size()-1);
488  } else {
489    OS << MAI.getAsciiDirective();
490  }
491
492  OS << ' ';
493  PrintQuotedString(Data, OS);
494  EmitEOL();
495}
496
497void MCAsmStreamer::EmitValue(const MCExpr *Value, unsigned Size,
498                              unsigned AddrSpace) {
499  assert(CurSection && "Cannot emit contents before setting section!");
500  const char *Directive = 0;
501  switch (Size) {
502  default: break;
503  case 1: Directive = MAI.getData8bitsDirective(AddrSpace); break;
504  case 2: Directive = MAI.getData16bitsDirective(AddrSpace); break;
505  case 4: Directive = MAI.getData32bitsDirective(AddrSpace); break;
506  case 8:
507    Directive = MAI.getData64bitsDirective(AddrSpace);
508    // If the target doesn't support 64-bit data, emit as two 32-bit halves.
509    if (Directive) break;
510    int64_t IntValue;
511    if (!Value->EvaluateAsAbsolute(IntValue))
512      report_fatal_error("Don't know how to emit this value.");
513    if (isLittleEndian()) {
514      EmitIntValue((uint32_t)(IntValue >> 0 ), 4, AddrSpace);
515      EmitIntValue((uint32_t)(IntValue >> 32), 4, AddrSpace);
516    } else {
517      EmitIntValue((uint32_t)(IntValue >> 32), 4, AddrSpace);
518      EmitIntValue((uint32_t)(IntValue >> 0 ), 4, AddrSpace);
519    }
520    return;
521  }
522
523  assert(Directive && "Invalid size for machine code value!");
524  OS << Directive << *Value;
525  EmitEOL();
526}
527
528void MCAsmStreamer::EmitULEB128Value(const MCExpr *Value, unsigned AddrSpace) {
529  int64_t IntValue;
530  if (Value->EvaluateAsAbsolute(IntValue)) {
531    SmallString<32> Tmp;
532    raw_svector_ostream OSE(Tmp);
533    MCObjectWriter::EncodeULEB128(IntValue, OSE);
534    EmitBytes(OSE.str(), AddrSpace);
535    return;
536  }
537  assert(MAI.hasLEB128() && "Cannot print a .uleb");
538  OS << ".uleb128 " << *Value;
539  EmitEOL();
540}
541
542void MCAsmStreamer::EmitSLEB128Value(const MCExpr *Value, unsigned AddrSpace) {
543  int64_t IntValue;
544  if (Value->EvaluateAsAbsolute(IntValue)) {
545    SmallString<32> Tmp;
546    raw_svector_ostream OSE(Tmp);
547    MCObjectWriter::EncodeSLEB128(IntValue, OSE);
548    EmitBytes(OSE.str(), AddrSpace);
549    return;
550  }
551  assert(MAI.hasLEB128() && "Cannot print a .sleb");
552  OS << ".sleb128 " << *Value;
553  EmitEOL();
554}
555
556void MCAsmStreamer::EmitGPRel32Value(const MCExpr *Value) {
557  assert(MAI.getGPRel32Directive() != 0);
558  OS << MAI.getGPRel32Directive() << *Value;
559  EmitEOL();
560}
561
562
563/// EmitFill - Emit NumBytes bytes worth of the value specified by
564/// FillValue.  This implements directives such as '.space'.
565void MCAsmStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue,
566                             unsigned AddrSpace) {
567  if (NumBytes == 0) return;
568
569  if (AddrSpace == 0)
570    if (const char *ZeroDirective = MAI.getZeroDirective()) {
571      OS << ZeroDirective << NumBytes;
572      if (FillValue != 0)
573        OS << ',' << (int)FillValue;
574      EmitEOL();
575      return;
576    }
577
578  // Emit a byte at a time.
579  MCStreamer::EmitFill(NumBytes, FillValue, AddrSpace);
580}
581
582void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
583                                         unsigned ValueSize,
584                                         unsigned MaxBytesToEmit) {
585  // Some assemblers don't support non-power of two alignments, so we always
586  // emit alignments as a power of two if possible.
587  if (isPowerOf2_32(ByteAlignment)) {
588    switch (ValueSize) {
589    default: llvm_unreachable("Invalid size for machine code value!");
590    case 1: OS << MAI.getAlignDirective(); break;
591    // FIXME: use MAI for this!
592    case 2: OS << ".p2alignw "; break;
593    case 4: OS << ".p2alignl "; break;
594    case 8: llvm_unreachable("Unsupported alignment size!");
595    }
596
597    if (MAI.getAlignmentIsInBytes())
598      OS << ByteAlignment;
599    else
600      OS << Log2_32(ByteAlignment);
601
602    if (Value || MaxBytesToEmit) {
603      OS << ", 0x";
604      OS.write_hex(truncateToSize(Value, ValueSize));
605
606      if (MaxBytesToEmit)
607        OS << ", " << MaxBytesToEmit;
608    }
609    EmitEOL();
610    return;
611  }
612
613  // Non-power of two alignment.  This is not widely supported by assemblers.
614  // FIXME: Parameterize this based on MAI.
615  switch (ValueSize) {
616  default: llvm_unreachable("Invalid size for machine code value!");
617  case 1: OS << ".balign";  break;
618  case 2: OS << ".balignw"; break;
619  case 4: OS << ".balignl"; break;
620  case 8: llvm_unreachable("Unsupported alignment size!");
621  }
622
623  OS << ' ' << ByteAlignment;
624  OS << ", " << truncateToSize(Value, ValueSize);
625  if (MaxBytesToEmit)
626    OS << ", " << MaxBytesToEmit;
627  EmitEOL();
628}
629
630void MCAsmStreamer::EmitCodeAlignment(unsigned ByteAlignment,
631                                      unsigned MaxBytesToEmit) {
632  // Emit with a text fill value.
633  EmitValueToAlignment(ByteAlignment, MAI.getTextAlignFillValue(),
634                       1, MaxBytesToEmit);
635}
636
637void MCAsmStreamer::EmitValueToOffset(const MCExpr *Offset,
638                                      unsigned char Value) {
639  // FIXME: Verify that Offset is associated with the current section.
640  OS << ".org " << *Offset << ", " << (unsigned) Value;
641  EmitEOL();
642}
643
644
645void MCAsmStreamer::EmitFileDirective(StringRef Filename) {
646  assert(MAI.hasSingleParameterDotFile());
647  OS << "\t.file\t";
648  PrintQuotedString(Filename, OS);
649  EmitEOL();
650}
651
652bool MCAsmStreamer::EmitDwarfFileDirective(unsigned FileNo, StringRef Filename){
653  if (!TLOF) {
654    OS << "\t.file\t" << FileNo << ' ';
655    PrintQuotedString(Filename, OS);
656    EmitEOL();
657  }
658  return this->MCStreamer::EmitDwarfFileDirective(FileNo, Filename);
659}
660
661void MCAsmStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
662                                          unsigned Column, unsigned Flags,
663                                          unsigned Isa,
664                                          unsigned Discriminator) {
665  this->MCStreamer::EmitDwarfLocDirective(FileNo, Line, Column, Flags,
666                                          Isa, Discriminator);
667  if (TLOF)
668    return;
669
670  OS << "\t.loc\t" << FileNo << " " << Line << " " << Column;
671  if (Flags & DWARF2_FLAG_BASIC_BLOCK)
672    OS << " basic_block";
673  if (Flags & DWARF2_FLAG_PROLOGUE_END)
674    OS << " prologue_end";
675  if (Flags & DWARF2_FLAG_EPILOGUE_BEGIN)
676    OS << " epilogue_begin";
677
678  unsigned OldFlags = getContext().getCurrentDwarfLoc().getFlags();
679  if ((Flags & DWARF2_FLAG_IS_STMT) != (OldFlags & DWARF2_FLAG_IS_STMT)) {
680    OS << " is_stmt ";
681
682    if (Flags & DWARF2_FLAG_IS_STMT)
683      OS << "1";
684    else
685      OS << "0";
686  }
687
688  if (Isa)
689    OS << "isa " << Isa;
690  if (Discriminator)
691    OS << "discriminator " << Discriminator;
692  EmitEOL();
693}
694
695bool MCAsmStreamer::EmitCFIStartProc() {
696  if (this->MCStreamer::EmitCFIStartProc())
697    return true;
698
699  OS << ".cfi_startproc";
700  EmitEOL();
701
702  return false;
703}
704
705bool MCAsmStreamer::EmitCFIEndProc() {
706  if (this->MCStreamer::EmitCFIEndProc())
707    return true;
708
709  OS << ".cfi_endproc";
710  EmitEOL();
711
712  return false;
713}
714
715bool MCAsmStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
716  if (this->MCStreamer::EmitCFIDefCfaOffset(Offset))
717    return true;
718
719  OS << ".cfi_def_cfa_offset " << Offset;
720  EmitEOL();
721
722  return false;
723}
724
725bool MCAsmStreamer::EmitCFIDefCfaRegister(int64_t Register) {
726  if (this->MCStreamer::EmitCFIDefCfaRegister(Register))
727    return true;
728
729  OS << ".cfi_def_cfa_register " << Register;
730  EmitEOL();
731
732  return false;
733}
734
735bool MCAsmStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
736  if (this->MCStreamer::EmitCFIOffset(Register, Offset))
737    return true;
738
739  OS << ".cfi_offset " << Register << ", " << Offset;
740  EmitEOL();
741
742  return false;
743}
744
745bool MCAsmStreamer::EmitCFIPersonality(const MCSymbol *Sym) {
746  if (this->MCStreamer::EmitCFIPersonality(Sym))
747    return true;
748
749  OS << ".cfi_personality 0, " << *Sym;
750  EmitEOL();
751
752  return false;
753}
754
755bool MCAsmStreamer::EmitCFILsda(const MCSymbol *Sym) {
756  if (this->MCStreamer::EmitCFILsda(Sym))
757    return true;
758
759  OS << ".cfi_lsda 0, " << *Sym;
760  EmitEOL();
761
762  return false;
763}
764
765void MCAsmStreamer::AddEncodingComment(const MCInst &Inst) {
766  raw_ostream &OS = GetCommentOS();
767  SmallString<256> Code;
768  SmallVector<MCFixup, 4> Fixups;
769  raw_svector_ostream VecOS(Code);
770  Emitter->EncodeInstruction(Inst, VecOS, Fixups);
771  VecOS.flush();
772
773  // If we are showing fixups, create symbolic markers in the encoded
774  // representation. We do this by making a per-bit map to the fixup item index,
775  // then trying to display it as nicely as possible.
776  SmallVector<uint8_t, 64> FixupMap;
777  FixupMap.resize(Code.size() * 8);
778  for (unsigned i = 0, e = Code.size() * 8; i != e; ++i)
779    FixupMap[i] = 0;
780
781  for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
782    MCFixup &F = Fixups[i];
783    const MCFixupKindInfo &Info = Emitter->getFixupKindInfo(F.getKind());
784    for (unsigned j = 0; j != Info.TargetSize; ++j) {
785      unsigned Index = F.getOffset() * 8 + Info.TargetOffset + j;
786      assert(Index < Code.size() * 8 && "Invalid offset in fixup!");
787      FixupMap[Index] = 1 + i;
788    }
789  }
790
791  OS << "encoding: [";
792  for (unsigned i = 0, e = Code.size(); i != e; ++i) {
793    if (i)
794      OS << ',';
795
796    // See if all bits are the same map entry.
797    uint8_t MapEntry = FixupMap[i * 8 + 0];
798    for (unsigned j = 1; j != 8; ++j) {
799      if (FixupMap[i * 8 + j] == MapEntry)
800        continue;
801
802      MapEntry = uint8_t(~0U);
803      break;
804    }
805
806    if (MapEntry != uint8_t(~0U)) {
807      if (MapEntry == 0) {
808        OS << format("0x%02x", uint8_t(Code[i]));
809      } else {
810        assert(Code[i] == 0 && "Encoder wrote into fixed up bit!");
811        OS << char('A' + MapEntry - 1);
812      }
813    } else {
814      // Otherwise, write out in binary.
815      OS << "0b";
816      for (unsigned j = 8; j--;) {
817        unsigned Bit = (Code[i] >> j) & 1;
818
819        unsigned FixupBit;
820        if (IsLittleEndian)
821          FixupBit = i * 8 + j;
822        else
823          FixupBit = i * 8 + (7-j);
824
825        if (uint8_t MapEntry = FixupMap[FixupBit]) {
826          assert(Bit == 0 && "Encoder wrote into fixed up bit!");
827          OS << char('A' + MapEntry - 1);
828        } else
829          OS << Bit;
830      }
831    }
832  }
833  OS << "]\n";
834
835  for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
836    MCFixup &F = Fixups[i];
837    const MCFixupKindInfo &Info = Emitter->getFixupKindInfo(F.getKind());
838    OS << "  fixup " << char('A' + i) << " - " << "offset: " << F.getOffset()
839       << ", value: " << *F.getValue() << ", kind: " << Info.Name << "\n";
840  }
841}
842
843void MCAsmStreamer::EmitInstruction(const MCInst &Inst) {
844  assert(CurSection && "Cannot emit contents before setting section!");
845
846  if (TLOF)
847    MCLineEntry::Make(this, getCurrentSection());
848
849  // Show the encoding in a comment if we have a code emitter.
850  if (Emitter)
851    AddEncodingComment(Inst);
852
853  // Show the MCInst if enabled.
854  if (ShowInst) {
855    Inst.dump_pretty(GetCommentOS(), &MAI, InstPrinter.get(), "\n ");
856    GetCommentOS() << "\n";
857  }
858
859  // If we have an AsmPrinter, use that to print, otherwise print the MCInst.
860  if (InstPrinter)
861    InstPrinter->printInst(&Inst, OS);
862  else
863    Inst.print(OS, &MAI);
864  EmitEOL();
865}
866
867/// EmitRawText - If this file is backed by an assembly streamer, this dumps
868/// the specified string in the output .s file.  This capability is
869/// indicated by the hasRawTextSupport() predicate.
870void MCAsmStreamer::EmitRawText(StringRef String) {
871  if (!String.empty() && String.back() == '\n')
872    String = String.substr(0, String.size()-1);
873  OS << String;
874  EmitEOL();
875}
876
877void MCAsmStreamer::Finish() {
878  // Dump out the dwarf file & directory tables and line tables.
879  if (getContext().hasDwarfFiles() && TLOF) {
880    MCDwarfFileTable::Emit(this, TLOF->getDwarfLineSection(), NULL,
881                           PointerSize);
882  }
883}
884
885MCStreamer *llvm::createAsmStreamer(MCContext &Context,
886                                    formatted_raw_ostream &OS,
887                                    bool isLittleEndian,
888                                    bool isVerboseAsm, MCInstPrinter *IP,
889                                    MCCodeEmitter *CE, bool ShowInst) {
890  return new MCAsmStreamer(Context, OS, isLittleEndian, isVerboseAsm,
891                           NULL, 0, IP, CE, ShowInst);
892}
893
894
895MCStreamer *llvm::createAsmStreamerNoLoc(MCContext &Context,
896                                         formatted_raw_ostream &OS,
897                                         bool isLittleEndian,
898                                         bool isVerboseAsm,
899                                         const TargetLoweringObjectFile *TLOF,
900                                         int PointerSize,
901                                         MCInstPrinter *IP,
902                                         MCCodeEmitter *CE, bool ShowInst) {
903  return new MCAsmStreamer(Context, OS, isLittleEndian, isVerboseAsm,
904                           TLOF, PointerSize, IP, CE, ShowInst);
905}
906