LLVM  4.0.0
ARMELFStreamer.cpp
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1 //===- lib/MC/ARMELFStreamer.cpp - ELF Object Output for ARM --------------===//
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 assembles .s files and emits ARM ELF .o object files. Different
11 // from generic ELF streamer in emitting mapping symbols ($a, $t and $d) to
12 // delimit regions of data and code.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #include "ARMRegisterInfo.h"
17 #include "ARMUnwindOpAsm.h"
18 #include "llvm/ADT/StringExtras.h"
19 #include "llvm/ADT/Twine.h"
20 #include "llvm/MC/MCAsmBackend.h"
21 #include "llvm/MC/MCAsmInfo.h"
22 #include "llvm/MC/MCAssembler.h"
23 #include "llvm/MC/MCCodeEmitter.h"
24 #include "llvm/MC/MCContext.h"
25 #include "llvm/MC/MCELFStreamer.h"
26 #include "llvm/MC/MCExpr.h"
27 #include "llvm/MC/MCInst.h"
28 #include "llvm/MC/MCInstPrinter.h"
31 #include "llvm/MC/MCRegisterInfo.h"
32 #include "llvm/MC/MCSection.h"
33 #include "llvm/MC/MCSectionELF.h"
34 #include "llvm/MC/MCStreamer.h"
35 #include "llvm/MC/MCSymbolELF.h"
36 #include "llvm/MC/MCValue.h"
38 #include "llvm/Support/ARMEHABI.h"
40 #include "llvm/Support/Debug.h"
41 #include "llvm/Support/ELF.h"
43 #include "llvm/Support/LEB128.h"
45 #include <algorithm>
46 
47 using namespace llvm;
48 
49 static std::string GetAEABIUnwindPersonalityName(unsigned Index) {
51  "Invalid personality index");
52  return (Twine("__aeabi_unwind_cpp_pr") + Twine(Index)).str();
53 }
54 
55 namespace {
56 
57 class ARMELFStreamer;
58 
59 class ARMTargetAsmStreamer : public ARMTargetStreamer {
61  MCInstPrinter &InstPrinter;
62  bool IsVerboseAsm;
63 
64  void emitFnStart() override;
65  void emitFnEnd() override;
66  void emitCantUnwind() override;
67  void emitPersonality(const MCSymbol *Personality) override;
68  void emitPersonalityIndex(unsigned Index) override;
69  void emitHandlerData() override;
70  void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0) override;
71  void emitMovSP(unsigned Reg, int64_t Offset = 0) override;
72  void emitPad(int64_t Offset) override;
73  void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
74  bool isVector) override;
75  void emitUnwindRaw(int64_t Offset,
76  const SmallVectorImpl<uint8_t> &Opcodes) override;
77 
78  void switchVendor(StringRef Vendor) override;
79  void emitAttribute(unsigned Attribute, unsigned Value) override;
80  void emitTextAttribute(unsigned Attribute, StringRef String) override;
81  void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
82  StringRef StringValue) override;
83  void emitArch(unsigned Arch) override;
84  void emitArchExtension(unsigned ArchExt) override;
85  void emitObjectArch(unsigned Arch) override;
86  void emitFPU(unsigned FPU) override;
87  void emitInst(uint32_t Inst, char Suffix = '\0') override;
88  void finishAttributeSection() override;
89 
90  void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE) override;
91  void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value) override;
92 
93 public:
94  ARMTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS,
95  MCInstPrinter &InstPrinter, bool VerboseAsm);
96 };
97 
98 ARMTargetAsmStreamer::ARMTargetAsmStreamer(MCStreamer &S,
100  MCInstPrinter &InstPrinter,
101  bool VerboseAsm)
102  : ARMTargetStreamer(S), OS(OS), InstPrinter(InstPrinter),
103  IsVerboseAsm(VerboseAsm) {}
104 void ARMTargetAsmStreamer::emitFnStart() { OS << "\t.fnstart\n"; }
105 void ARMTargetAsmStreamer::emitFnEnd() { OS << "\t.fnend\n"; }
106 void ARMTargetAsmStreamer::emitCantUnwind() { OS << "\t.cantunwind\n"; }
107 void ARMTargetAsmStreamer::emitPersonality(const MCSymbol *Personality) {
108  OS << "\t.personality " << Personality->getName() << '\n';
109 }
110 void ARMTargetAsmStreamer::emitPersonalityIndex(unsigned Index) {
111  OS << "\t.personalityindex " << Index << '\n';
112 }
113 void ARMTargetAsmStreamer::emitHandlerData() { OS << "\t.handlerdata\n"; }
114 void ARMTargetAsmStreamer::emitSetFP(unsigned FpReg, unsigned SpReg,
115  int64_t Offset) {
116  OS << "\t.setfp\t";
117  InstPrinter.printRegName(OS, FpReg);
118  OS << ", ";
119  InstPrinter.printRegName(OS, SpReg);
120  if (Offset)
121  OS << ", #" << Offset;
122  OS << '\n';
123 }
124 void ARMTargetAsmStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
125  assert((Reg != ARM::SP && Reg != ARM::PC) &&
126  "the operand of .movsp cannot be either sp or pc");
127 
128  OS << "\t.movsp\t";
129  InstPrinter.printRegName(OS, Reg);
130  if (Offset)
131  OS << ", #" << Offset;
132  OS << '\n';
133 }
134 void ARMTargetAsmStreamer::emitPad(int64_t Offset) {
135  OS << "\t.pad\t#" << Offset << '\n';
136 }
137 void ARMTargetAsmStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
138  bool isVector) {
139  assert(RegList.size() && "RegList should not be empty");
140  if (isVector)
141  OS << "\t.vsave\t{";
142  else
143  OS << "\t.save\t{";
144 
145  InstPrinter.printRegName(OS, RegList[0]);
146 
147  for (unsigned i = 1, e = RegList.size(); i != e; ++i) {
148  OS << ", ";
149  InstPrinter.printRegName(OS, RegList[i]);
150  }
151 
152  OS << "}\n";
153 }
154 void ARMTargetAsmStreamer::switchVendor(StringRef Vendor) {
155 }
156 void ARMTargetAsmStreamer::emitAttribute(unsigned Attribute, unsigned Value) {
157  OS << "\t.eabi_attribute\t" << Attribute << ", " << Twine(Value);
158  if (IsVerboseAsm) {
160  if (!Name.empty())
161  OS << "\t@ " << Name;
162  }
163  OS << "\n";
164 }
165 void ARMTargetAsmStreamer::emitTextAttribute(unsigned Attribute,
166  StringRef String) {
167  switch (Attribute) {
169  OS << "\t.cpu\t" << String.lower();
170  break;
171  default:
172  OS << "\t.eabi_attribute\t" << Attribute << ", \"" << String << "\"";
173  if (IsVerboseAsm) {
175  if (!Name.empty())
176  OS << "\t@ " << Name;
177  }
178  break;
179  }
180  OS << "\n";
181 }
182 void ARMTargetAsmStreamer::emitIntTextAttribute(unsigned Attribute,
183  unsigned IntValue,
184  StringRef StringValue) {
185  switch (Attribute) {
186  default: llvm_unreachable("unsupported multi-value attribute in asm mode");
188  OS << "\t.eabi_attribute\t" << Attribute << ", " << IntValue;
189  if (!StringValue.empty())
190  OS << ", \"" << StringValue << "\"";
191  if (IsVerboseAsm)
192  OS << "\t@ " << ARMBuildAttrs::AttrTypeAsString(Attribute);
193  break;
194  }
195  OS << "\n";
196 }
197 void ARMTargetAsmStreamer::emitArch(unsigned Arch) {
198  OS << "\t.arch\t" << ARM::getArchName(Arch) << "\n";
199 }
200 void ARMTargetAsmStreamer::emitArchExtension(unsigned ArchExt) {
201  OS << "\t.arch_extension\t" << ARM::getArchExtName(ArchExt) << "\n";
202 }
203 void ARMTargetAsmStreamer::emitObjectArch(unsigned Arch) {
204  OS << "\t.object_arch\t" << ARM::getArchName(Arch) << '\n';
205 }
206 void ARMTargetAsmStreamer::emitFPU(unsigned FPU) {
207  OS << "\t.fpu\t" << ARM::getFPUName(FPU) << "\n";
208 }
209 void ARMTargetAsmStreamer::finishAttributeSection() {
210 }
211 void
212 ARMTargetAsmStreamer::AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *S) {
213  OS << "\t.tlsdescseq\t" << S->getSymbol().getName();
214 }
215 
216 void ARMTargetAsmStreamer::emitThumbSet(MCSymbol *Symbol, const MCExpr *Value) {
217  const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo();
218 
219  OS << "\t.thumb_set\t";
220  Symbol->print(OS, MAI);
221  OS << ", ";
222  Value->print(OS, MAI);
223  OS << '\n';
224 }
225 
226 void ARMTargetAsmStreamer::emitInst(uint32_t Inst, char Suffix) {
227  OS << "\t.inst";
228  if (Suffix)
229  OS << "." << Suffix;
230  OS << "\t0x" << Twine::utohexstr(Inst) << "\n";
231 }
232 
233 void ARMTargetAsmStreamer::emitUnwindRaw(int64_t Offset,
234  const SmallVectorImpl<uint8_t> &Opcodes) {
235  OS << "\t.unwind_raw " << Offset;
236  for (SmallVectorImpl<uint8_t>::const_iterator OCI = Opcodes.begin(),
237  OCE = Opcodes.end();
238  OCI != OCE; ++OCI)
239  OS << ", 0x" << Twine::utohexstr(*OCI);
240  OS << '\n';
241 }
242 
243 class ARMTargetELFStreamer : public ARMTargetStreamer {
244 private:
245  // This structure holds all attributes, accounting for
246  // their string/numeric value, so we can later emit them
247  // in declaration order, keeping all in the same vector
248  struct AttributeItem {
249  enum {
250  HiddenAttribute = 0,
251  NumericAttribute,
252  TextAttribute,
253  NumericAndTextAttributes
254  } Type;
255  unsigned Tag;
256  unsigned IntValue;
257  std::string StringValue;
258 
259  static bool LessTag(const AttributeItem &LHS, const AttributeItem &RHS) {
260  // The conformance tag must be emitted first when serialised
261  // into an object file. Specifically, the addenda to the ARM ABI
262  // states that (2.3.7.4):
263  //
264  // "To simplify recognition by consumers in the common case of
265  // claiming conformity for the whole file, this tag should be
266  // emitted first in a file-scope sub-subsection of the first
267  // public subsection of the attributes section."
268  //
269  // So it is special-cased in this comparison predicate when the
270  // attributes are sorted in finishAttributeSection().
271  return (RHS.Tag != ARMBuildAttrs::conformance) &&
272  ((LHS.Tag == ARMBuildAttrs::conformance) || (LHS.Tag < RHS.Tag));
273  }
274  };
275 
276  StringRef CurrentVendor;
277  unsigned FPU;
278  unsigned Arch;
279  unsigned EmittedArch;
281 
282  MCSection *AttributeSection;
283 
284  AttributeItem *getAttributeItem(unsigned Attribute) {
285  for (size_t i = 0; i < Contents.size(); ++i)
286  if (Contents[i].Tag == Attribute)
287  return &Contents[i];
288  return nullptr;
289  }
290 
291  void setAttributeItem(unsigned Attribute, unsigned Value,
292  bool OverwriteExisting) {
293  // Look for existing attribute item
294  if (AttributeItem *Item = getAttributeItem(Attribute)) {
295  if (!OverwriteExisting)
296  return;
297  Item->Type = AttributeItem::NumericAttribute;
298  Item->IntValue = Value;
299  return;
300  }
301 
302  // Create new attribute item
303  AttributeItem Item = {
304  AttributeItem::NumericAttribute,
305  Attribute,
306  Value,
307  StringRef("")
308  };
309  Contents.push_back(Item);
310  }
311 
312  void setAttributeItem(unsigned Attribute, StringRef Value,
313  bool OverwriteExisting) {
314  // Look for existing attribute item
315  if (AttributeItem *Item = getAttributeItem(Attribute)) {
316  if (!OverwriteExisting)
317  return;
318  Item->Type = AttributeItem::TextAttribute;
319  Item->StringValue = Value;
320  return;
321  }
322 
323  // Create new attribute item
324  AttributeItem Item = {
325  AttributeItem::TextAttribute,
326  Attribute,
327  0,
328  Value
329  };
330  Contents.push_back(Item);
331  }
332 
333  void setAttributeItems(unsigned Attribute, unsigned IntValue,
334  StringRef StringValue, bool OverwriteExisting) {
335  // Look for existing attribute item
336  if (AttributeItem *Item = getAttributeItem(Attribute)) {
337  if (!OverwriteExisting)
338  return;
339  Item->Type = AttributeItem::NumericAndTextAttributes;
340  Item->IntValue = IntValue;
341  Item->StringValue = StringValue;
342  return;
343  }
344 
345  // Create new attribute item
346  AttributeItem Item = {
347  AttributeItem::NumericAndTextAttributes,
348  Attribute,
349  IntValue,
350  StringValue
351  };
352  Contents.push_back(Item);
353  }
354 
355  void emitArchDefaultAttributes();
356  void emitFPUDefaultAttributes();
357 
358  ARMELFStreamer &getStreamer();
359 
360  void emitFnStart() override;
361  void emitFnEnd() override;
362  void emitCantUnwind() override;
363  void emitPersonality(const MCSymbol *Personality) override;
364  void emitPersonalityIndex(unsigned Index) override;
365  void emitHandlerData() override;
366  void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0) override;
367  void emitMovSP(unsigned Reg, int64_t Offset = 0) override;
368  void emitPad(int64_t Offset) override;
369  void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
370  bool isVector) override;
371  void emitUnwindRaw(int64_t Offset,
372  const SmallVectorImpl<uint8_t> &Opcodes) override;
373 
374  void switchVendor(StringRef Vendor) override;
375  void emitAttribute(unsigned Attribute, unsigned Value) override;
376  void emitTextAttribute(unsigned Attribute, StringRef String) override;
377  void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
378  StringRef StringValue) override;
379  void emitArch(unsigned Arch) override;
380  void emitObjectArch(unsigned Arch) override;
381  void emitFPU(unsigned FPU) override;
382  void emitInst(uint32_t Inst, char Suffix = '\0') override;
383  void finishAttributeSection() override;
384  void emitLabel(MCSymbol *Symbol) override;
385 
386  void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE) override;
387  void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value) override;
388 
389  size_t calculateContentSize() const;
390 
391  // Reset state between object emissions
392  void reset() override;
393 
394 public:
395  ARMTargetELFStreamer(MCStreamer &S)
396  : ARMTargetStreamer(S), CurrentVendor("aeabi"), FPU(ARM::FK_INVALID),
397  Arch(ARM::AK_INVALID), EmittedArch(ARM::AK_INVALID),
398  AttributeSection(nullptr) {}
399 };
400 
401 /// Extend the generic ELFStreamer class so that it can emit mapping symbols at
402 /// the appropriate points in the object files. These symbols are defined in the
403 /// ARM ELF ABI: infocenter.arm.com/help/topic/com.arm.../IHI0044D_aaelf.pdf.
404 ///
405 /// In brief: $a, $t or $d should be emitted at the start of each contiguous
406 /// region of ARM code, Thumb code or data in a section. In practice, this
407 /// emission does not rely on explicit assembler directives but on inherent
408 /// properties of the directives doing the emission (e.g. ".byte" is data, "add
409 /// r0, r0, r0" an instruction).
410 ///
411 /// As a result this system is orthogonal to the DataRegion infrastructure used
412 /// by MachO. Beware!
413 class ARMELFStreamer : public MCELFStreamer {
414 public:
415  friend class ARMTargetELFStreamer;
416 
417  ARMELFStreamer(MCContext &Context, MCAsmBackend &TAB, raw_pwrite_stream &OS,
418  MCCodeEmitter *Emitter, bool IsThumb)
419  : MCELFStreamer(Context, TAB, OS, Emitter), IsThumb(IsThumb),
420  MappingSymbolCounter(0), LastEMS(EMS_None) {
421  EHReset();
422  }
423 
424  ~ARMELFStreamer() {}
425 
426  void FinishImpl() override;
427 
428  // ARM exception handling directives
429  void emitFnStart();
430  void emitFnEnd();
431  void emitCantUnwind();
432  void emitPersonality(const MCSymbol *Per);
433  void emitPersonalityIndex(unsigned index);
434  void emitHandlerData();
435  void emitSetFP(unsigned NewFpReg, unsigned NewSpReg, int64_t Offset = 0);
436  void emitMovSP(unsigned Reg, int64_t Offset = 0);
437  void emitPad(int64_t Offset);
438  void emitRegSave(const SmallVectorImpl<unsigned> &RegList, bool isVector);
439  void emitUnwindRaw(int64_t Offset, const SmallVectorImpl<uint8_t> &Opcodes);
440 
441  void ChangeSection(MCSection *Section, const MCExpr *Subsection) override {
442  // We have to keep track of the mapping symbol state of any sections we
443  // use. Each one should start off as EMS_None, which is provided as the
444  // default constructor by DenseMap::lookup.
445  LastMappingSymbols[getPreviousSection().first] = LastEMS;
446  LastEMS = LastMappingSymbols.lookup(Section);
447 
448  MCELFStreamer::ChangeSection(Section, Subsection);
449  }
450 
451  /// This function is the one used to emit instruction data into the ELF
452  /// streamer. We override it to add the appropriate mapping symbol if
453  /// necessary.
454  void EmitInstruction(const MCInst& Inst,
455  const MCSubtargetInfo &STI) override {
456  if (IsThumb)
457  EmitThumbMappingSymbol();
458  else
459  EmitARMMappingSymbol();
460 
462  }
463 
464  void emitInst(uint32_t Inst, char Suffix) {
465  unsigned Size;
466  char Buffer[4];
467  const bool LittleEndian = getContext().getAsmInfo()->isLittleEndian();
468 
469  switch (Suffix) {
470  case '\0':
471  Size = 4;
472 
473  assert(!IsThumb);
474  EmitARMMappingSymbol();
475  for (unsigned II = 0, IE = Size; II != IE; II++) {
476  const unsigned I = LittleEndian ? (Size - II - 1) : II;
477  Buffer[Size - II - 1] = uint8_t(Inst >> I * CHAR_BIT);
478  }
479 
480  break;
481  case 'n':
482  case 'w':
483  Size = (Suffix == 'n' ? 2 : 4);
484 
485  assert(IsThumb);
486  EmitThumbMappingSymbol();
487  for (unsigned II = 0, IE = Size; II != IE; II = II + 2) {
488  const unsigned I0 = LittleEndian ? II + 0 : (Size - II - 1);
489  const unsigned I1 = LittleEndian ? II + 1 : (Size - II - 2);
490  Buffer[Size - II - 2] = uint8_t(Inst >> I0 * CHAR_BIT);
491  Buffer[Size - II - 1] = uint8_t(Inst >> I1 * CHAR_BIT);
492  }
493 
494  break;
495  default:
496  llvm_unreachable("Invalid Suffix");
497  }
498 
499  MCELFStreamer::EmitBytes(StringRef(Buffer, Size));
500  }
501 
502  /// This is one of the functions used to emit data into an ELF section, so the
503  /// ARM streamer overrides it to add the appropriate mapping symbol ($d) if
504  /// necessary.
505  void EmitBytes(StringRef Data) override {
506  EmitDataMappingSymbol();
508  }
509 
510  /// This is one of the functions used to emit data into an ELF section, so the
511  /// ARM streamer overrides it to add the appropriate mapping symbol ($d) if
512  /// necessary.
513  void EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override {
514  if (const MCSymbolRefExpr *SRE = dyn_cast_or_null<MCSymbolRefExpr>(Value))
515  if (SRE->getKind() == MCSymbolRefExpr::VK_ARM_SBREL && !(Size == 4)) {
516  getContext().reportError(Loc, "relocated expression must be 32-bit");
517  return;
518  }
519 
520  EmitDataMappingSymbol();
521  MCELFStreamer::EmitValueImpl(Value, Size, Loc);
522  }
523 
524  void EmitAssemblerFlag(MCAssemblerFlag Flag) override {
526 
527  switch (Flag) {
528  case MCAF_SyntaxUnified:
529  return; // no-op here.
530  case MCAF_Code16:
531  IsThumb = true;
532  return; // Change to Thumb mode
533  case MCAF_Code32:
534  IsThumb = false;
535  return; // Change to ARM mode
536  case MCAF_Code64:
537  return;
539  return;
540  }
541  }
542 
543 private:
544  enum ElfMappingSymbol {
545  EMS_None,
546  EMS_ARM,
547  EMS_Thumb,
548  EMS_Data
549  };
550 
551  void EmitDataMappingSymbol() {
552  if (LastEMS == EMS_Data) return;
553  EmitMappingSymbol("$d");
554  LastEMS = EMS_Data;
555  }
556 
557  void EmitThumbMappingSymbol() {
558  if (LastEMS == EMS_Thumb) return;
559  EmitMappingSymbol("$t");
560  LastEMS = EMS_Thumb;
561  }
562 
563  void EmitARMMappingSymbol() {
564  if (LastEMS == EMS_ARM) return;
565  EmitMappingSymbol("$a");
566  LastEMS = EMS_ARM;
567  }
568 
569  void EmitMappingSymbol(StringRef Name) {
570  auto *Symbol = cast<MCSymbolELF>(getContext().getOrCreateSymbol(
571  Name + "." + Twine(MappingSymbolCounter++)));
572  EmitLabel(Symbol);
573 
574  Symbol->setType(ELF::STT_NOTYPE);
575  Symbol->setBinding(ELF::STB_LOCAL);
576  Symbol->setExternal(false);
577  }
578 
579  void EmitThumbFunc(MCSymbol *Func) override {
582  }
583 
584  // Helper functions for ARM exception handling directives
585  void EHReset();
586 
587  // Reset state between object emissions
588  void reset() override;
589 
590  void EmitPersonalityFixup(StringRef Name);
591  void FlushPendingOffset();
592  void FlushUnwindOpcodes(bool NoHandlerData);
593 
594  void SwitchToEHSection(StringRef Prefix, unsigned Type, unsigned Flags,
595  SectionKind Kind, const MCSymbol &Fn);
596  void SwitchToExTabSection(const MCSymbol &FnStart);
597  void SwitchToExIdxSection(const MCSymbol &FnStart);
598 
599  void EmitFixup(const MCExpr *Expr, MCFixupKind Kind);
600 
601  bool IsThumb;
602  int64_t MappingSymbolCounter;
603 
605  ElfMappingSymbol LastEMS;
606 
607  // ARM Exception Handling Frame Information
608  MCSymbol *ExTab;
609  MCSymbol *FnStart;
610  const MCSymbol *Personality;
611  unsigned PersonalityIndex;
612  unsigned FPReg; // Frame pointer register
613  int64_t FPOffset; // Offset: (final frame pointer) - (initial $sp)
614  int64_t SPOffset; // Offset: (final $sp) - (initial $sp)
615  int64_t PendingOffset; // Offset: (final $sp) - (emitted $sp)
616  bool UsedFP;
617  bool CantUnwind;
618  SmallVector<uint8_t, 64> Opcodes;
619  UnwindOpcodeAssembler UnwindOpAsm;
620 };
621 } // end anonymous namespace
622 
623 ARMELFStreamer &ARMTargetELFStreamer::getStreamer() {
624  return static_cast<ARMELFStreamer &>(Streamer);
625 }
626 
627 void ARMTargetELFStreamer::emitFnStart() { getStreamer().emitFnStart(); }
628 void ARMTargetELFStreamer::emitFnEnd() { getStreamer().emitFnEnd(); }
629 void ARMTargetELFStreamer::emitCantUnwind() { getStreamer().emitCantUnwind(); }
630 void ARMTargetELFStreamer::emitPersonality(const MCSymbol *Personality) {
631  getStreamer().emitPersonality(Personality);
632 }
633 void ARMTargetELFStreamer::emitPersonalityIndex(unsigned Index) {
634  getStreamer().emitPersonalityIndex(Index);
635 }
636 void ARMTargetELFStreamer::emitHandlerData() {
637  getStreamer().emitHandlerData();
638 }
639 void ARMTargetELFStreamer::emitSetFP(unsigned FpReg, unsigned SpReg,
640  int64_t Offset) {
641  getStreamer().emitSetFP(FpReg, SpReg, Offset);
642 }
643 void ARMTargetELFStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
644  getStreamer().emitMovSP(Reg, Offset);
645 }
646 void ARMTargetELFStreamer::emitPad(int64_t Offset) {
647  getStreamer().emitPad(Offset);
648 }
649 void ARMTargetELFStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
650  bool isVector) {
651  getStreamer().emitRegSave(RegList, isVector);
652 }
653 void ARMTargetELFStreamer::emitUnwindRaw(int64_t Offset,
654  const SmallVectorImpl<uint8_t> &Opcodes) {
655  getStreamer().emitUnwindRaw(Offset, Opcodes);
656 }
657 void ARMTargetELFStreamer::switchVendor(StringRef Vendor) {
658  assert(!Vendor.empty() && "Vendor cannot be empty.");
659 
660  if (CurrentVendor == Vendor)
661  return;
662 
663  if (!CurrentVendor.empty())
664  finishAttributeSection();
665 
666  assert(Contents.empty() &&
667  ".ARM.attributes should be flushed before changing vendor");
668  CurrentVendor = Vendor;
669 
670 }
671 void ARMTargetELFStreamer::emitAttribute(unsigned Attribute, unsigned Value) {
672  setAttributeItem(Attribute, Value, /* OverwriteExisting= */ true);
673 }
674 void ARMTargetELFStreamer::emitTextAttribute(unsigned Attribute,
675  StringRef Value) {
676  setAttributeItem(Attribute, Value, /* OverwriteExisting= */ true);
677 }
678 void ARMTargetELFStreamer::emitIntTextAttribute(unsigned Attribute,
679  unsigned IntValue,
680  StringRef StringValue) {
681  setAttributeItems(Attribute, IntValue, StringValue,
682  /* OverwriteExisting= */ true);
683 }
684 void ARMTargetELFStreamer::emitArch(unsigned Value) {
685  Arch = Value;
686 }
687 void ARMTargetELFStreamer::emitObjectArch(unsigned Value) {
688  EmittedArch = Value;
689 }
690 void ARMTargetELFStreamer::emitArchDefaultAttributes() {
691  using namespace ARMBuildAttrs;
692 
693  setAttributeItem(CPU_name,
694  ARM::getCPUAttr(Arch),
695  false);
696 
697  if (EmittedArch == ARM::AK_INVALID)
698  setAttributeItem(CPU_arch,
699  ARM::getArchAttr(Arch),
700  false);
701  else
702  setAttributeItem(CPU_arch,
703  ARM::getArchAttr(EmittedArch),
704  false);
705 
706  switch (Arch) {
707  case ARM::AK_ARMV2:
708  case ARM::AK_ARMV2A:
709  case ARM::AK_ARMV3:
710  case ARM::AK_ARMV3M:
711  case ARM::AK_ARMV4:
712  setAttributeItem(ARM_ISA_use, Allowed, false);
713  break;
714 
715  case ARM::AK_ARMV4T:
716  case ARM::AK_ARMV5T:
717  case ARM::AK_ARMV5TE:
718  case ARM::AK_ARMV6:
719  setAttributeItem(ARM_ISA_use, Allowed, false);
720  setAttributeItem(THUMB_ISA_use, Allowed, false);
721  break;
722 
723  case ARM::AK_ARMV6T2:
724  setAttributeItem(ARM_ISA_use, Allowed, false);
725  setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
726  break;
727 
728  case ARM::AK_ARMV6K:
729  case ARM::AK_ARMV6KZ:
730  setAttributeItem(ARM_ISA_use, Allowed, false);
731  setAttributeItem(THUMB_ISA_use, Allowed, false);
732  setAttributeItem(Virtualization_use, AllowTZ, false);
733  break;
734 
735  case ARM::AK_ARMV6M:
736  setAttributeItem(THUMB_ISA_use, Allowed, false);
737  break;
738 
739  case ARM::AK_ARMV7A:
740  setAttributeItem(CPU_arch_profile, ApplicationProfile, false);
741  setAttributeItem(ARM_ISA_use, Allowed, false);
742  setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
743  break;
744 
745  case ARM::AK_ARMV7R:
746  setAttributeItem(CPU_arch_profile, RealTimeProfile, false);
747  setAttributeItem(ARM_ISA_use, Allowed, false);
748  setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
749  break;
750 
751  case ARM::AK_ARMV7M:
752  setAttributeItem(CPU_arch_profile, MicroControllerProfile, false);
753  setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
754  break;
755 
756  case ARM::AK_ARMV8A:
757  case ARM::AK_ARMV8_1A:
758  case ARM::AK_ARMV8_2A:
759  setAttributeItem(CPU_arch_profile, ApplicationProfile, false);
760  setAttributeItem(ARM_ISA_use, Allowed, false);
761  setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
762  setAttributeItem(MPextension_use, Allowed, false);
763  setAttributeItem(Virtualization_use, AllowTZVirtualization, false);
764  break;
765 
766  case ARM::AK_ARMV8MBaseline:
767  case ARM::AK_ARMV8MMainline:
768  setAttributeItem(THUMB_ISA_use, AllowThumbDerived, false);
769  setAttributeItem(CPU_arch_profile, MicroControllerProfile, false);
770  break;
771 
772  case ARM::AK_IWMMXT:
773  setAttributeItem(ARM_ISA_use, Allowed, false);
774  setAttributeItem(THUMB_ISA_use, Allowed, false);
775  setAttributeItem(WMMX_arch, AllowWMMXv1, false);
776  break;
777 
778  case ARM::AK_IWMMXT2:
779  setAttributeItem(ARM_ISA_use, Allowed, false);
780  setAttributeItem(THUMB_ISA_use, Allowed, false);
781  setAttributeItem(WMMX_arch, AllowWMMXv2, false);
782  break;
783 
784  default:
785  report_fatal_error("Unknown Arch: " + Twine(Arch));
786  break;
787  }
788 }
789 void ARMTargetELFStreamer::emitFPU(unsigned Value) {
790  FPU = Value;
791 }
792 void ARMTargetELFStreamer::emitFPUDefaultAttributes() {
793  switch (FPU) {
794  case ARM::FK_VFP:
795  case ARM::FK_VFPV2:
796  setAttributeItem(ARMBuildAttrs::FP_arch,
798  /* OverwriteExisting= */ false);
799  break;
800 
801  case ARM::FK_VFPV3:
802  setAttributeItem(ARMBuildAttrs::FP_arch,
804  /* OverwriteExisting= */ false);
805  break;
806 
807  case ARM::FK_VFPV3_FP16:
808  setAttributeItem(ARMBuildAttrs::FP_arch,
810  /* OverwriteExisting= */ false);
811  setAttributeItem(ARMBuildAttrs::FP_HP_extension,
813  /* OverwriteExisting= */ false);
814  break;
815 
816  case ARM::FK_VFPV3_D16:
817  setAttributeItem(ARMBuildAttrs::FP_arch,
819  /* OverwriteExisting= */ false);
820  break;
821 
822  case ARM::FK_VFPV3_D16_FP16:
823  setAttributeItem(ARMBuildAttrs::FP_arch,
825  /* OverwriteExisting= */ false);
826  setAttributeItem(ARMBuildAttrs::FP_HP_extension,
828  /* OverwriteExisting= */ false);
829  break;
830 
831  case ARM::FK_VFPV3XD:
832  setAttributeItem(ARMBuildAttrs::FP_arch,
834  /* OverwriteExisting= */ false);
835  break;
836  case ARM::FK_VFPV3XD_FP16:
837  setAttributeItem(ARMBuildAttrs::FP_arch,
839  /* OverwriteExisting= */ false);
840  setAttributeItem(ARMBuildAttrs::FP_HP_extension,
842  /* OverwriteExisting= */ false);
843  break;
844 
845  case ARM::FK_VFPV4:
846  setAttributeItem(ARMBuildAttrs::FP_arch,
848  /* OverwriteExisting= */ false);
849  break;
850 
851  // ABI_HardFP_use is handled in ARMAsmPrinter, so _SP_D16 is treated the same
852  // as _D16 here.
853  case ARM::FK_FPV4_SP_D16:
854  case ARM::FK_VFPV4_D16:
855  setAttributeItem(ARMBuildAttrs::FP_arch,
857  /* OverwriteExisting= */ false);
858  break;
859 
860  case ARM::FK_FP_ARMV8:
861  setAttributeItem(ARMBuildAttrs::FP_arch,
863  /* OverwriteExisting= */ false);
864  break;
865 
866  // FPV5_D16 is identical to FP_ARMV8 except for the number of D registers, so
867  // uses the FP_ARMV8_D16 build attribute.
868  case ARM::FK_FPV5_SP_D16:
869  case ARM::FK_FPV5_D16:
870  setAttributeItem(ARMBuildAttrs::FP_arch,
872  /* OverwriteExisting= */ false);
873  break;
874 
875  case ARM::FK_NEON:
876  setAttributeItem(ARMBuildAttrs::FP_arch,
878  /* OverwriteExisting= */ false);
879  setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
881  /* OverwriteExisting= */ false);
882  break;
883 
884  case ARM::FK_NEON_FP16:
885  setAttributeItem(ARMBuildAttrs::FP_arch,
887  /* OverwriteExisting= */ false);
888  setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
890  /* OverwriteExisting= */ false);
891  setAttributeItem(ARMBuildAttrs::FP_HP_extension,
893  /* OverwriteExisting= */ false);
894  break;
895 
896  case ARM::FK_NEON_VFPV4:
897  setAttributeItem(ARMBuildAttrs::FP_arch,
899  /* OverwriteExisting= */ false);
900  setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
902  /* OverwriteExisting= */ false);
903  break;
904 
905  case ARM::FK_NEON_FP_ARMV8:
906  case ARM::FK_CRYPTO_NEON_FP_ARMV8:
907  setAttributeItem(ARMBuildAttrs::FP_arch,
909  /* OverwriteExisting= */ false);
910  // 'Advanced_SIMD_arch' must be emitted not here, but within
911  // ARMAsmPrinter::emitAttributes(), depending on hasV8Ops() and hasV8_1a()
912  break;
913 
914  case ARM::FK_SOFTVFP:
915  case ARM::FK_NONE:
916  break;
917 
918  default:
919  report_fatal_error("Unknown FPU: " + Twine(FPU));
920  break;
921  }
922 }
923 size_t ARMTargetELFStreamer::calculateContentSize() const {
924  size_t Result = 0;
925  for (size_t i = 0; i < Contents.size(); ++i) {
926  AttributeItem item = Contents[i];
927  switch (item.Type) {
928  case AttributeItem::HiddenAttribute:
929  break;
930  case AttributeItem::NumericAttribute:
931  Result += getULEB128Size(item.Tag);
932  Result += getULEB128Size(item.IntValue);
933  break;
934  case AttributeItem::TextAttribute:
935  Result += getULEB128Size(item.Tag);
936  Result += item.StringValue.size() + 1; // string + '\0'
937  break;
938  case AttributeItem::NumericAndTextAttributes:
939  Result += getULEB128Size(item.Tag);
940  Result += getULEB128Size(item.IntValue);
941  Result += item.StringValue.size() + 1; // string + '\0';
942  break;
943  }
944  }
945  return Result;
946 }
947 void ARMTargetELFStreamer::finishAttributeSection() {
948  // <format-version>
949  // [ <section-length> "vendor-name"
950  // [ <file-tag> <size> <attribute>*
951  // | <section-tag> <size> <section-number>* 0 <attribute>*
952  // | <symbol-tag> <size> <symbol-number>* 0 <attribute>*
953  // ]+
954  // ]*
955 
956  if (FPU != ARM::FK_INVALID)
957  emitFPUDefaultAttributes();
958 
959  if (Arch != ARM::AK_INVALID)
960  emitArchDefaultAttributes();
961 
962  if (Contents.empty())
963  return;
964 
965  std::sort(Contents.begin(), Contents.end(), AttributeItem::LessTag);
966 
967  ARMELFStreamer &Streamer = getStreamer();
968 
969  // Switch to .ARM.attributes section
970  if (AttributeSection) {
971  Streamer.SwitchSection(AttributeSection);
972  } else {
973  AttributeSection = Streamer.getContext().getELFSection(
974  ".ARM.attributes", ELF::SHT_ARM_ATTRIBUTES, 0);
975  Streamer.SwitchSection(AttributeSection);
976 
977  // Format version
978  Streamer.EmitIntValue(0x41, 1);
979  }
980 
981  // Vendor size + Vendor name + '\0'
982  const size_t VendorHeaderSize = 4 + CurrentVendor.size() + 1;
983 
984  // Tag + Tag Size
985  const size_t TagHeaderSize = 1 + 4;
986 
987  const size_t ContentsSize = calculateContentSize();
988 
989  Streamer.EmitIntValue(VendorHeaderSize + TagHeaderSize + ContentsSize, 4);
990  Streamer.EmitBytes(CurrentVendor);
991  Streamer.EmitIntValue(0, 1); // '\0'
992 
993  Streamer.EmitIntValue(ARMBuildAttrs::File, 1);
994  Streamer.EmitIntValue(TagHeaderSize + ContentsSize, 4);
995 
996  // Size should have been accounted for already, now
997  // emit each field as its type (ULEB or String)
998  for (size_t i = 0; i < Contents.size(); ++i) {
999  AttributeItem item = Contents[i];
1000  Streamer.EmitULEB128IntValue(item.Tag);
1001  switch (item.Type) {
1002  default: llvm_unreachable("Invalid attribute type");
1003  case AttributeItem::NumericAttribute:
1004  Streamer.EmitULEB128IntValue(item.IntValue);
1005  break;
1006  case AttributeItem::TextAttribute:
1007  Streamer.EmitBytes(item.StringValue);
1008  Streamer.EmitIntValue(0, 1); // '\0'
1009  break;
1010  case AttributeItem::NumericAndTextAttributes:
1011  Streamer.EmitULEB128IntValue(item.IntValue);
1012  Streamer.EmitBytes(item.StringValue);
1013  Streamer.EmitIntValue(0, 1); // '\0'
1014  break;
1015  }
1016  }
1017 
1018  Contents.clear();
1019  FPU = ARM::FK_INVALID;
1020 }
1021 
1022 void ARMTargetELFStreamer::emitLabel(MCSymbol *Symbol) {
1023  ARMELFStreamer &Streamer = getStreamer();
1024  if (!Streamer.IsThumb)
1025  return;
1026 
1027  Streamer.getAssembler().registerSymbol(*Symbol);
1028  unsigned Type = cast<MCSymbolELF>(Symbol)->getType();
1029  if (Type == ELF::STT_FUNC || Type == ELF::STT_GNU_IFUNC)
1030  Streamer.EmitThumbFunc(Symbol);
1031 }
1032 
1033 void
1034 ARMTargetELFStreamer::AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *S) {
1035  getStreamer().EmitFixup(S, FK_Data_4);
1036 }
1037 
1038 void ARMTargetELFStreamer::emitThumbSet(MCSymbol *Symbol, const MCExpr *Value) {
1039  if (const MCSymbolRefExpr *SRE = dyn_cast<MCSymbolRefExpr>(Value)) {
1040  const MCSymbol &Sym = SRE->getSymbol();
1041  if (!Sym.isDefined()) {
1042  getStreamer().EmitAssignment(Symbol, Value);
1043  return;
1044  }
1045  }
1046 
1047  getStreamer().EmitThumbFunc(Symbol);
1048  getStreamer().EmitAssignment(Symbol, Value);
1049 }
1050 
1051 void ARMTargetELFStreamer::emitInst(uint32_t Inst, char Suffix) {
1052  getStreamer().emitInst(Inst, Suffix);
1053 }
1054 
1055 void ARMTargetELFStreamer::reset() { AttributeSection = nullptr; }
1056 
1057 void ARMELFStreamer::FinishImpl() {
1058  MCTargetStreamer &TS = *getTargetStreamer();
1059  ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS);
1060  ATS.finishAttributeSection();
1061 
1062  MCELFStreamer::FinishImpl();
1063 }
1064 
1065 void ARMELFStreamer::reset() {
1066  MCTargetStreamer &TS = *getTargetStreamer();
1067  ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS);
1068  ATS.reset();
1069  MappingSymbolCounter = 0;
1070  MCELFStreamer::reset();
1071  // MCELFStreamer clear's the assembler's e_flags. However, for
1072  // arm we manually set the ABI version on streamer creation, so
1073  // do the same here
1074  getAssembler().setELFHeaderEFlags(ELF::EF_ARM_EABI_VER5);
1075 }
1076 
1077 inline void ARMELFStreamer::SwitchToEHSection(StringRef Prefix,
1078  unsigned Type,
1079  unsigned Flags,
1080  SectionKind Kind,
1081  const MCSymbol &Fn) {
1082  const MCSectionELF &FnSection =
1083  static_cast<const MCSectionELF &>(Fn.getSection());
1084 
1085  // Create the name for new section
1086  StringRef FnSecName(FnSection.getSectionName());
1087  SmallString<128> EHSecName(Prefix);
1088  if (FnSecName != ".text") {
1089  EHSecName += FnSecName;
1090  }
1091 
1092  // Get .ARM.extab or .ARM.exidx section
1093  const MCSymbolELF *Group = FnSection.getGroup();
1094  if (Group)
1095  Flags |= ELF::SHF_GROUP;
1096  MCSectionELF *EHSection =
1097  getContext().getELFSection(EHSecName, Type, Flags, 0, Group,
1098  FnSection.getUniqueID(), nullptr, &FnSection);
1099 
1100  assert(EHSection && "Failed to get the required EH section");
1101 
1102  // Switch to .ARM.extab or .ARM.exidx section
1103  SwitchSection(EHSection);
1104  EmitCodeAlignment(4);
1105 }
1106 
1107 inline void ARMELFStreamer::SwitchToExTabSection(const MCSymbol &FnStart) {
1108  SwitchToEHSection(".ARM.extab", ELF::SHT_PROGBITS, ELF::SHF_ALLOC,
1109  SectionKind::getData(), FnStart);
1110 }
1111 
1112 inline void ARMELFStreamer::SwitchToExIdxSection(const MCSymbol &FnStart) {
1113  SwitchToEHSection(".ARM.exidx", ELF::SHT_ARM_EXIDX,
1115  SectionKind::getData(), FnStart);
1116 }
1117 void ARMELFStreamer::EmitFixup(const MCExpr *Expr, MCFixupKind Kind) {
1118  MCDataFragment *Frag = getOrCreateDataFragment();
1119  Frag->getFixups().push_back(MCFixup::create(Frag->getContents().size(), Expr,
1120  Kind));
1121 }
1122 
1123 void ARMELFStreamer::EHReset() {
1124  ExTab = nullptr;
1125  FnStart = nullptr;
1126  Personality = nullptr;
1127  PersonalityIndex = ARM::EHABI::NUM_PERSONALITY_INDEX;
1128  FPReg = ARM::SP;
1129  FPOffset = 0;
1130  SPOffset = 0;
1131  PendingOffset = 0;
1132  UsedFP = false;
1133  CantUnwind = false;
1134 
1135  Opcodes.clear();
1136  UnwindOpAsm.Reset();
1137 }
1138 
1139 void ARMELFStreamer::emitFnStart() {
1140  assert(FnStart == nullptr);
1141  FnStart = getContext().createTempSymbol();
1142  EmitLabel(FnStart);
1143 }
1144 
1145 void ARMELFStreamer::emitFnEnd() {
1146  assert(FnStart && ".fnstart must precedes .fnend");
1147 
1148  // Emit unwind opcodes if there is no .handlerdata directive
1149  if (!ExTab && !CantUnwind)
1150  FlushUnwindOpcodes(true);
1151 
1152  // Emit the exception index table entry
1153  SwitchToExIdxSection(*FnStart);
1154 
1155  if (PersonalityIndex < ARM::EHABI::NUM_PERSONALITY_INDEX)
1156  EmitPersonalityFixup(GetAEABIUnwindPersonalityName(PersonalityIndex));
1157 
1158  const MCSymbolRefExpr *FnStartRef =
1159  MCSymbolRefExpr::create(FnStart,
1160  MCSymbolRefExpr::VK_ARM_PREL31,
1161  getContext());
1162 
1163  EmitValue(FnStartRef, 4);
1164 
1165  if (CantUnwind) {
1166  EmitIntValue(ARM::EHABI::EXIDX_CANTUNWIND, 4);
1167  } else if (ExTab) {
1168  // Emit a reference to the unwind opcodes in the ".ARM.extab" section.
1169  const MCSymbolRefExpr *ExTabEntryRef =
1170  MCSymbolRefExpr::create(ExTab,
1171  MCSymbolRefExpr::VK_ARM_PREL31,
1172  getContext());
1173  EmitValue(ExTabEntryRef, 4);
1174  } else {
1175  // For the __aeabi_unwind_cpp_pr0, we have to emit the unwind opcodes in
1176  // the second word of exception index table entry. The size of the unwind
1177  // opcodes should always be 4 bytes.
1178  assert(PersonalityIndex == ARM::EHABI::AEABI_UNWIND_CPP_PR0 &&
1179  "Compact model must use __aeabi_unwind_cpp_pr0 as personality");
1180  assert(Opcodes.size() == 4u &&
1181  "Unwind opcode size for __aeabi_unwind_cpp_pr0 must be equal to 4");
1182  uint64_t Intval = Opcodes[0] |
1183  Opcodes[1] << 8 |
1184  Opcodes[2] << 16 |
1185  Opcodes[3] << 24;
1186  EmitIntValue(Intval, Opcodes.size());
1187  }
1188 
1189  // Switch to the section containing FnStart
1190  SwitchSection(&FnStart->getSection());
1191 
1192  // Clean exception handling frame information
1193  EHReset();
1194 }
1195 
1196 void ARMELFStreamer::emitCantUnwind() { CantUnwind = true; }
1197 
1198 // Add the R_ARM_NONE fixup at the same position
1199 void ARMELFStreamer::EmitPersonalityFixup(StringRef Name) {
1200  const MCSymbol *PersonalitySym = getContext().getOrCreateSymbol(Name);
1201 
1202  const MCSymbolRefExpr *PersonalityRef = MCSymbolRefExpr::create(
1203  PersonalitySym, MCSymbolRefExpr::VK_ARM_NONE, getContext());
1204 
1205  visitUsedExpr(*PersonalityRef);
1206  MCDataFragment *DF = getOrCreateDataFragment();
1207  DF->getFixups().push_back(MCFixup::create(DF->getContents().size(),
1208  PersonalityRef,
1209  MCFixup::getKindForSize(4, false)));
1210 }
1211 
1212 void ARMELFStreamer::FlushPendingOffset() {
1213  if (PendingOffset != 0) {
1214  UnwindOpAsm.EmitSPOffset(-PendingOffset);
1215  PendingOffset = 0;
1216  }
1217 }
1218 
1219 void ARMELFStreamer::FlushUnwindOpcodes(bool NoHandlerData) {
1220  // Emit the unwind opcode to restore $sp.
1221  if (UsedFP) {
1222  const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1223  int64_t LastRegSaveSPOffset = SPOffset - PendingOffset;
1224  UnwindOpAsm.EmitSPOffset(LastRegSaveSPOffset - FPOffset);
1225  UnwindOpAsm.EmitSetSP(MRI->getEncodingValue(FPReg));
1226  } else {
1227  FlushPendingOffset();
1228  }
1229 
1230  // Finalize the unwind opcode sequence
1231  UnwindOpAsm.Finalize(PersonalityIndex, Opcodes);
1232 
1233  // For compact model 0, we have to emit the unwind opcodes in the .ARM.exidx
1234  // section. Thus, we don't have to create an entry in the .ARM.extab
1235  // section.
1236  if (NoHandlerData && PersonalityIndex == ARM::EHABI::AEABI_UNWIND_CPP_PR0)
1237  return;
1238 
1239  // Switch to .ARM.extab section.
1240  SwitchToExTabSection(*FnStart);
1241 
1242  // Create .ARM.extab label for offset in .ARM.exidx
1243  assert(!ExTab);
1244  ExTab = getContext().createTempSymbol();
1245  EmitLabel(ExTab);
1246 
1247  // Emit personality
1248  if (Personality) {
1249  const MCSymbolRefExpr *PersonalityRef =
1250  MCSymbolRefExpr::create(Personality,
1251  MCSymbolRefExpr::VK_ARM_PREL31,
1252  getContext());
1253 
1254  EmitValue(PersonalityRef, 4);
1255  }
1256 
1257  // Emit unwind opcodes
1258  assert((Opcodes.size() % 4) == 0 &&
1259  "Unwind opcode size for __aeabi_cpp_unwind_pr0 must be multiple of 4");
1260  for (unsigned I = 0; I != Opcodes.size(); I += 4) {
1261  uint64_t Intval = Opcodes[I] |
1262  Opcodes[I + 1] << 8 |
1263  Opcodes[I + 2] << 16 |
1264  Opcodes[I + 3] << 24;
1265  EmitIntValue(Intval, 4);
1266  }
1267 
1268  // According to ARM EHABI section 9.2, if the __aeabi_unwind_cpp_pr1() or
1269  // __aeabi_unwind_cpp_pr2() is used, then the handler data must be emitted
1270  // after the unwind opcodes. The handler data consists of several 32-bit
1271  // words, and should be terminated by zero.
1272  //
1273  // In case that the .handlerdata directive is not specified by the
1274  // programmer, we should emit zero to terminate the handler data.
1275  if (NoHandlerData && !Personality)
1276  EmitIntValue(0, 4);
1277 }
1278 
1279 void ARMELFStreamer::emitHandlerData() { FlushUnwindOpcodes(false); }
1280 
1281 void ARMELFStreamer::emitPersonality(const MCSymbol *Per) {
1282  Personality = Per;
1283  UnwindOpAsm.setPersonality(Per);
1284 }
1285 
1286 void ARMELFStreamer::emitPersonalityIndex(unsigned Index) {
1287  assert(Index < ARM::EHABI::NUM_PERSONALITY_INDEX && "invalid index");
1288  PersonalityIndex = Index;
1289 }
1290 
1291 void ARMELFStreamer::emitSetFP(unsigned NewFPReg, unsigned NewSPReg,
1292  int64_t Offset) {
1293  assert((NewSPReg == ARM::SP || NewSPReg == FPReg) &&
1294  "the operand of .setfp directive should be either $sp or $fp");
1295 
1296  UsedFP = true;
1297  FPReg = NewFPReg;
1298 
1299  if (NewSPReg == ARM::SP)
1300  FPOffset = SPOffset + Offset;
1301  else
1302  FPOffset += Offset;
1303 }
1304 
1305 void ARMELFStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
1306  assert((Reg != ARM::SP && Reg != ARM::PC) &&
1307  "the operand of .movsp cannot be either sp or pc");
1308  assert(FPReg == ARM::SP && "current FP must be SP");
1309 
1310  FlushPendingOffset();
1311 
1312  FPReg = Reg;
1313  FPOffset = SPOffset + Offset;
1314 
1315  const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1316  UnwindOpAsm.EmitSetSP(MRI->getEncodingValue(FPReg));
1317 }
1318 
1319 void ARMELFStreamer::emitPad(int64_t Offset) {
1320  // Track the change of the $sp offset
1321  SPOffset -= Offset;
1322 
1323  // To squash multiple .pad directives, we should delay the unwind opcode
1324  // until the .save, .vsave, .handlerdata, or .fnend directives.
1325  PendingOffset -= Offset;
1326 }
1327 
1328 void ARMELFStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
1329  bool IsVector) {
1330  // Collect the registers in the register list
1331  unsigned Count = 0;
1332  uint32_t Mask = 0;
1333  const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1334  for (size_t i = 0; i < RegList.size(); ++i) {
1335  unsigned Reg = MRI->getEncodingValue(RegList[i]);
1336  assert(Reg < (IsVector ? 32U : 16U) && "Register out of range");
1337  unsigned Bit = (1u << Reg);
1338  if ((Mask & Bit) == 0) {
1339  Mask |= Bit;
1340  ++Count;
1341  }
1342  }
1343 
1344  // Track the change the $sp offset: For the .save directive, the
1345  // corresponding push instruction will decrease the $sp by (4 * Count).
1346  // For the .vsave directive, the corresponding vpush instruction will
1347  // decrease $sp by (8 * Count).
1348  SPOffset -= Count * (IsVector ? 8 : 4);
1349 
1350  // Emit the opcode
1351  FlushPendingOffset();
1352  if (IsVector)
1353  UnwindOpAsm.EmitVFPRegSave(Mask);
1354  else
1355  UnwindOpAsm.EmitRegSave(Mask);
1356 }
1357 
1358 void ARMELFStreamer::emitUnwindRaw(int64_t Offset,
1359  const SmallVectorImpl<uint8_t> &Opcodes) {
1360  FlushPendingOffset();
1361  SPOffset = SPOffset - Offset;
1362  UnwindOpAsm.EmitRaw(Opcodes);
1363 }
1364 
1365 namespace llvm {
1366 
1369  MCInstPrinter *InstPrint,
1370  bool isVerboseAsm) {
1371  return new ARMTargetAsmStreamer(S, OS, *InstPrint, isVerboseAsm);
1372 }
1373 
1375  return new ARMTargetStreamer(S);
1376 }
1377 
1379  const MCSubtargetInfo &STI) {
1380  const Triple &TT = STI.getTargetTriple();
1381  if (TT.isOSBinFormatELF())
1382  return new ARMTargetELFStreamer(S);
1383  return new ARMTargetStreamer(S);
1384 }
1385 
1387  raw_pwrite_stream &OS,
1388  MCCodeEmitter *Emitter, bool RelaxAll,
1389  bool IsThumb) {
1390  ARMELFStreamer *S = new ARMELFStreamer(Context, TAB, OS, Emitter, IsThumb);
1391  // FIXME: This should eventually end up somewhere else where more
1392  // intelligent flag decisions can be made. For now we are just maintaining
1393  // the status quo for ARM and setting EF_ARM_EABI_VER5 as the default.
1394  S->getAssembler().setELFHeaderEFlags(ELF::EF_ARM_EABI_VER5);
1395 
1396  if (RelaxAll)
1397  S->getAssembler().setRelaxAll(true);
1398  return S;
1399  }
1400 
1401 }
1402 
1403 
void setIsThumbFunc(const MCSymbol *Func)
Flag a function symbol as the target of a .thumb_func directive.
Definition: MCAssembler.h:227
Instances of this class represent a uniqued identifier for a section in the current translation unit...
Definition: MCSection.h:40
virtual void emitInst(uint32_t Inst, char Suffix= '\0')
MCELFStreamer * createARMELFStreamer(MCContext &Context, MCAsmBackend &TAB, raw_pwrite_stream &OS, MCCodeEmitter *Emitter, bool RelaxAll, bool IsThumb)
virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE)
virtual void emitFPU(unsigned FPU)
MCSectionSubPair getPreviousSection() const
Return the previous section that the streamer is emitting code to.
Definition: MCStreamer.h:305
const MCAsmInfo * getAsmInfo() const
Definition: MCContext.h:243
StringRef getSectionName() const
Definition: MCSectionELF.h:74
void EmitBytes(StringRef Data) override
Emit the bytes in Data into the output.
LLVMContext & Context
const MCSymbol & getSymbol() const
Definition: MCExpr.h:311
void print(raw_ostream &OS, const MCAsmInfo *MAI) const
print - Print the value to the stream OS.
Definition: MCSymbol.cpp:53
LLVM_ATTRIBUTE_NORETURN void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
size_t i
void reset() override
state management
Definition: MCELFStreamer.h:36
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:39
formatted_raw_ostream - A raw_ostream that wraps another one and keeps track of line and column posit...
Attribute
Attributes.
Definition: Dwarf.h:94
Target specific streamer interface.
Definition: MCStreamer.h:73
virtual void emitPad(int64_t Offset)
unsigned getUniqueID() const
Definition: MCSectionELF.h:87
virtual void finishAttributeSection()
FunctionType * getType(LLVMContext &Context, ID id, ArrayRef< Type * > Tys=None)
Return the function type for an intrinsic.
Definition: Function.cpp:905
StringRef getArchExtName(unsigned ArchExtKind)
virtual void emitPersonality(const MCSymbol *Personality)
StringRef getFPUName(unsigned FPUKind)
unsigned getArchAttr(unsigned ArchKind)
virtual void reset()
Reset any state between object emissions, i.e.
virtual void emitPersonalityIndex(unsigned Index)
StringRef getArchName(unsigned ArchKind)
struct fuzzer::@269 Flags
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:34
bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override
Add the given Attribute to Symbol.
Reg
All possible values of the reg field in the ModR/M byte.
void EmitLabel(MCSymbol *Symbol) override
Emit a label for Symbol into the current section.
Represent a reference to a symbol from inside an expression.
Definition: MCExpr.h:161
virtual void emitLabel(MCSymbol *Symbol)
Definition: MCStreamer.cpp:40
MCContext & getContext() const
Definition: MCStreamer.h:221
bool isLittleEndian() const
True if the target is little endian.
Definition: MCAsmInfo.h:392
A four-byte fixup.
Definition: MCFixup.h:26
Context object for machine code objects.
Definition: MCContext.h:51
void EmitThumbFunc(MCSymbol *Func) override
Note in the output that the specified Func is a Thumb mode function (ARM target only).
.code16 (X86) / .code 16 (ARM)
Definition: MCDirectives.h:51
void EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc=SMLoc()) override
Emit the expression Value into the output as a native integer of the given Size bytes.
const MCSymbolELF * getGroup() const
Definition: MCSectionELF.h:79
virtual void emitMovSP(unsigned Reg, int64_t Offset=0)
void setExternal(bool Value) const
Definition: MCSymbol.h:387
SmallVectorImpl< char > & getContents()
Definition: MCFragment.h:175
MCTargetStreamer * createARMTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS, MCInstPrinter *InstPrint, bool isVerboseAsm)
Instances of this class represent a single low-level machine instruction.
Definition: MCInst.h:150
virtual void emitAttribute(unsigned Attribute, unsigned Value)
Flag
These should be considered private to the implementation of the MCInstrDesc class.
Definition: MCInstrDesc.h:121
MCRegisterInfo base class - We assume that the target defines a static array of MCRegisterDesc object...
This class is intended to be used as a base class for asm properties and features specific to the tar...
Definition: MCAsmInfo.h:57
StringRef AttrTypeAsString(unsigned Attr, bool HasTagPrefix=true)
void ChangeSection(MCSection *Section, const MCExpr *Subsection) override
Update streamer for a new active section.
MCTargetStreamer * createARMObjectTargetStreamer(MCStreamer &S, const MCSubtargetInfo &STI)
Streaming machine code generation interface.
Definition: MCStreamer.h:161
virtual void emitRegSave(const SmallVectorImpl< unsigned > &RegList, bool isVector)
unsigned const MachineRegisterInfo * MRI
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:115
virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value)
MCAssembler & getAssembler()
virtual void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset=0)
MCCodeEmitter - Generic instruction encoding interface.
Definition: MCCodeEmitter.h:23
virtual void emitObjectArch(unsigned Arch)
MCFixupKind
Extensible enumeration to represent the type of a fixup.
Definition: MCFixup.h:23
SmallVectorImpl< MCFixup > & getFixups()
Definition: MCFragment.h:200
uint32_t Offset
virtual void emitUnwindRaw(int64_t StackOffset, const SmallVectorImpl< uint8_t > &Opcodes)
Special entry for the function never unwind.
Definition: ARMEHABI.h:36
void reportError(SMLoc L, const Twine &Msg)
Definition: MCContext.cpp:510
.subsections_via_symbols (MachO)
Definition: MCDirectives.h:50
SectionKind - This is a simple POD value that classifies the properties of a section.
Definition: SectionKind.h:23
#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
unsigned getULEB128Size(uint64_t Value)
Utility function to get the size of the ULEB128-encoded value.
Definition: LEB128.cpp:20
MCStreamer & getStreamer()
Definition: MCStreamer.h:81
void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override
Emit the given Instruction into the current section.
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:843
bool isVector(MCInstrInfo const &MCII, MCInst const &MCI)
bool isDefined(bool SetUsed=true) const
isDefined - Check if this symbol is defined (i.e., it has an address).
Definition: MCSymbol.h:245
.syntax (ARM/ELF)
Definition: MCDirectives.h:49
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:130
MCSection & getSection(bool SetUsed=true) const
Get the section associated with a defined, non-absolute symbol.
Definition: MCSymbol.h:264
.code32 (X86) / .code 32 (ARM)
Definition: MCDirectives.h:52
.code64 (X86)
Definition: MCDirectives.h:53
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator end()
Definition: SmallVector.h:119
StringRef getCPUAttr(unsigned ArchKind)
This is an instance of a target assembly language printer that converts an MCInst to valid target ass...
Definition: MCInstPrinter.h:41
bool isOSBinFormatELF() const
Tests whether the OS uses the ELF binary format.
Definition: Triple.h:565
StringRef getName() const
getName - Get the symbol name.
Definition: MCSymbol.h:199
MCSymbol * getOrCreateSymbol(const Twine &Name)
Lookup the symbol inside with the specified Name.
Definition: MCContext.cpp:114
MCAssemblerFlag
Definition: MCDirectives.h:48
.type _foo, STT_FUNC # aka
Definition: MCDirectives.h:23
virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue, StringRef StringValue="")
#define I(x, y, z)
Definition: MD5.cpp:54
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:135
MCSubtargetInfo - Generic base class for all target subtargets.
This represents a section on linux, lots of unix variants and some bare metal systems.
Definition: MCSectionELF.h:30
const Triple & getTargetTriple() const
getTargetTriple - Return the target triple string.
static std::string utohexstr(uint64_t X, bool LowerCase=false)
Definition: StringExtras.h:48
void print(raw_ostream &OS, const MCAsmInfo *MAI, bool InParens=false) const
Definition: MCExpr.cpp:33
An abstract base class for streams implementations that also support a pwrite operation.
Definition: raw_ostream.h:333
const unsigned Kind
Fragment for data and encoded instructions.
Definition: MCFragment.h:218
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
MCTargetStreamer * createARMNullTargetStreamer(MCStreamer &S)
cl::opt< bool > RelaxAll("mc-relax-all", cl::desc("When used with filetype=obj, ""relax all fixups in the emitted object file"))
uint16_t getEncodingValue(unsigned RegNo) const
Returns the encoding for RegNo.
LLVM Value Representation.
Definition: Value.h:71
Generic interface to target specific assembler backends.
Definition: MCAsmBackend.h:36
std::underlying_type< E >::type Mask()
Get a bitmask with 1s in all places up to the high-order bit of E's largest value.
Definition: BitmaskEnum.h:81
void EmitAssemblerFlag(MCAssemblerFlag Flag) override
Note in the output the specified Flag.
static TraceState * TS
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:47
virtual void emitArch(unsigned Arch)
static std::string GetAEABIUnwindPersonalityName(unsigned Index)
Represents a location in source code.
Definition: SMLoc.h:24
void FinishImpl() override
Streamer specific finalization.
LLVM_NODISCARD std::string lower() const
Definition: StringRef.cpp:122
virtual void switchVendor(StringRef Vendor)
virtual void emitTextAttribute(unsigned Attribute, StringRef String)
char * PC