lib/IR/DIBuilder.cpp

   1 //===--- DIBuilder.cpp - Debug Information Builder ------------------------===//
   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 implements the DIBuilder.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/IR/DIBuilder.h"
  15 #include "llvm/ADT/STLExtras.h"
  16 #include "llvm/IR/Constants.h"
  17 #include "llvm/IR/DebugInfo.h"
  18 #include "llvm/IR/IntrinsicInst.h"
  19 #include "llvm/IR/Module.h"
  20 #include "llvm/Support/Debug.h"
  21 #include "llvm/Support/Dwarf.h"
  22
  23 using namespace llvm;
  24 using namespace llvm::dwarf;
  25
  26 namespace {
  27 class HeaderBuilder {
  28   /// \brief Whether there are any fields yet.
  29   ///
  30   /// Note that this is not equivalent to \c Chars.empty(), since \a concat()
  31   /// may have been called already with an empty string.
  32   bool IsEmpty;
  33   SmallVector<char, 256> Chars;
  34
  35 public:
  36   HeaderBuilder() : IsEmpty(true) {}
  37   HeaderBuilder(const HeaderBuilder &X) : IsEmpty(X.IsEmpty), Chars(X.Chars) {}
  38   HeaderBuilder(HeaderBuilder &&X)
  39       : IsEmpty(X.IsEmpty), Chars(std::move(X.Chars)) {}
  40
  41   template <class Twineable> HeaderBuilder &concat(Twineable &&X) {
  42     if (IsEmpty)
  43       IsEmpty = false;
  44     else
  45       Chars.push_back(0);
  46     Twine(X).toVector(Chars);
  47     return *this;
  48   }
  49
  50   MDString *get(LLVMContext &Context) const {
  51     return MDString::get(Context, StringRef(Chars.begin(), Chars.size()));
  52   }
  53
  54   static HeaderBuilder get(unsigned Tag) {
  55     return HeaderBuilder().concat("0x" + Twine::utohexstr(Tag));
  56   }
  57 };
  58 }
  59
  60 DIBuilder::DIBuilder(Module &m, bool AllowUnresolvedNodes)
  61     : M(m), VMContext(M.getContext()), TempEnumTypes(nullptr),
  62       TempRetainTypes(nullptr), TempSubprograms(nullptr), TempGVs(nullptr),
  63       DeclareFn(nullptr), ValueFn(nullptr),
  64       AllowUnresolvedNodes(AllowUnresolvedNodes) {}
  65
  66 void DIBuilder::trackIfUnresolved(MDNode *N) {
  67   if (!N)
  68     return;
  69   if (N->isResolved())
  70     return;
  71
  72   assert(AllowUnresolvedNodes && "Cannot handle unresolved nodes");
  73   UnresolvedNodes.emplace_back(N);
  74 }
  75
  76 void DIBuilder::finalize() {
  77   TempEnumTypes->replaceAllUsesWith(MDTuple::get(VMContext, AllEnumTypes));
  78
  79   SmallVector<Metadata *, 16> RetainValues;
  80   // Declarations and definitions of the same type may be retained. Some
  81   // clients RAUW these pairs, leaving duplicates in the retained types
  82   // list. Use a set to remove the duplicates while we transform the
  83   // TrackingVHs back into Values.
  84   SmallPtrSet<Metadata *, 16> RetainSet;
  85   for (unsigned I = 0, E = AllRetainTypes.size(); I < E; I++)
  86     if (RetainSet.insert(AllRetainTypes[I]).second)
  87       RetainValues.push_back(AllRetainTypes[I]);
  88   TempRetainTypes->replaceAllUsesWith(MDTuple::get(VMContext, RetainValues));
  89
  90   DISubprogramArray SPs = MDTuple::get(VMContext, AllSubprograms);
  91   TempSubprograms->replaceAllUsesWith(SPs.get());
  92   for (auto *SP : SPs) {
  93     if (MDTuple *Temp = SP->getVariables().get()) {
  94       const auto &PV = PreservedVariables.lookup(SP);
  95       SmallVector<Metadata *, 4> Variables(PV.begin(), PV.end());
  96       DINodeArray AV = getOrCreateArray(Variables);
  97       TempMDTuple(Temp)->replaceAllUsesWith(AV.get());
  98     }
  99   }
 100
 101   TempGVs->replaceAllUsesWith(MDTuple::get(VMContext, AllGVs));
 102
 103   TempImportedModules->replaceAllUsesWith(MDTuple::get(
 104       VMContext, SmallVector<Metadata *, 16>(AllImportedModules.begin(),
 105                                              AllImportedModules.end())));
 106
 107   // Now that all temp nodes have been replaced or deleted, resolve remaining
 108   // cycles.
 109   for (const auto &N : UnresolvedNodes)
 110     if (N && !N->isResolved())
 111       N->resolveCycles();
 112   UnresolvedNodes.clear();
 113
 114   // Can't handle unresolved nodes anymore.
 115   AllowUnresolvedNodes = false;
 116 }
 117
 118 /// If N is compile unit return NULL otherwise return N.
 119 static DIScope *getNonCompileUnitScope(DIScope *N) {
 120   if (!N || isa<DICompileUnit>(N))
 121     return nullptr;
 122   return cast<DIScope>(N);
 123 }
 124
 125 DICompileUnit *DIBuilder::createCompileUnit(
 126     unsigned Lang, StringRef Filename, StringRef Directory, StringRef Producer,
 127     bool isOptimized, StringRef Flags, unsigned RunTimeVer, StringRef SplitName,
 128     DebugEmissionKind Kind, uint64_t DWOId, bool EmitDebugInfo) {
 129
 130   assert(((Lang <= dwarf::DW_LANG_Fortran08 && Lang >= dwarf::DW_LANG_C89) ||
 131           (Lang <= dwarf::DW_LANG_hi_user && Lang >= dwarf::DW_LANG_lo_user)) &&
 132          "Invalid Language tag");
 133   assert(!Filename.empty() &&
 134          "Unable to create compile unit without filename");
 135
 136   // TODO: Once we make DICompileUnit distinct, stop using temporaries here
 137   // (just start with operands assigned to nullptr).
 138   TempEnumTypes = MDTuple::getTemporary(VMContext, None);
 139   TempRetainTypes = MDTuple::getTemporary(VMContext, None);
 140   TempSubprograms = MDTuple::getTemporary(VMContext, None);
 141   TempGVs = MDTuple::getTemporary(VMContext, None);
 142   TempImportedModules = MDTuple::getTemporary(VMContext, None);
 143
 144   DICompileUnit *CUNode = DICompileUnit::getDistinct(
 145       VMContext, Lang, DIFile::get(VMContext, Filename, Directory), Producer,
 146       isOptimized, Flags, RunTimeVer, SplitName, Kind, TempEnumTypes.get(),
 147       TempRetainTypes.get(), TempSubprograms.get(), TempGVs.get(),
 148       TempImportedModules.get(), DWOId);
 149
 150   // Create a named metadata so that it is easier to find cu in a module.
 151   // Note that we only generate this when the caller wants to actually
 152   // emit debug information. When we are only interested in tracking
 153   // source line locations throughout the backend, we prevent codegen from
 154   // emitting debug info in the final output by not generating llvm.dbg.cu.
 155   if (EmitDebugInfo) {
 156     NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.cu");
 157     NMD->addOperand(CUNode);
 158   }
 159
 160   trackIfUnresolved(CUNode);
 161   return CUNode;
 162 }
 163
 164 static DIImportedEntity *
 165 createImportedModule(LLVMContext &C, dwarf::Tag Tag, DIScope *Context,
 166                      Metadata *NS, unsigned Line, StringRef Name,
 167                      SmallVectorImpl<TrackingMDNodeRef> &AllImportedModules) {
 168   auto *M = DIImportedEntity::get(C, Tag, Context, DINodeRef(NS), Line, Name);
 169   AllImportedModules.emplace_back(M);
 170   return M;
 171 }
 172
 173 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 174                                                   DINamespace *NS,
 175                                                   unsigned Line) {
 176   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 177                                 Context, NS, Line, StringRef(), AllImportedModules);
 178 }
 179
 180 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 181                                                   DIImportedEntity *NS,
 182                                                   unsigned Line) {
 183   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 184                                 Context, NS, Line, StringRef(), AllImportedModules);
 185 }
 186
 187 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context, DIModule *M,
 188                                                   unsigned Line) {
 189   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 190                                 Context, M, Line, StringRef(), AllImportedModules);
 191 }
 192
 193 DIImportedEntity *DIBuilder::createImportedDeclaration(DIScope *Context,
 194                                                        DINode *Decl,
 195                                                        unsigned Line,
 196                                                        StringRef Name) {
 197   // Make sure to use the unique identifier based metadata reference for
 198   // types that have one.
 199   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_declaration,
 200                                 Context, DINodeRef::get(Decl), Line, Name,
 201                                 AllImportedModules);
 202 }
 203
 204 DIFile *DIBuilder::createFile(StringRef Filename, StringRef Directory) {
 205   return DIFile::get(VMContext, Filename, Directory);
 206 }
 207
 208 DIEnumerator *DIBuilder::createEnumerator(StringRef Name, int64_t Val) {
 209   assert(!Name.empty() && "Unable to create enumerator without name");
 210   return DIEnumerator::get(VMContext, Val, Name);
 211 }
 212
 213 DIBasicType *DIBuilder::createUnspecifiedType(StringRef Name) {
 214   assert(!Name.empty() && "Unable to create type without name");
 215   return DIBasicType::get(VMContext, dwarf::DW_TAG_unspecified_type, Name);
 216 }
 217
 218 DIBasicType *DIBuilder::createNullPtrType() {
 219   return createUnspecifiedType("decltype(nullptr)");
 220 }
 221
 222 DIBasicType *DIBuilder::createBasicType(StringRef Name, uint64_t SizeInBits,
 223                                         uint64_t AlignInBits,
 224                                         unsigned Encoding) {
 225   assert(!Name.empty() && "Unable to create type without name");
 226   return DIBasicType::get(VMContext, dwarf::DW_TAG_base_type, Name, SizeInBits,
 227                           AlignInBits, Encoding);
 228 }
 229
 230 DIDerivedType *DIBuilder::createQualifiedType(unsigned Tag, DIType *FromTy) {
 231   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr,
 232                             DITypeRef::get(FromTy), 0, 0, 0, 0);
 233 }
 234
 235 DIDerivedType *DIBuilder::createPointerType(DIType *PointeeTy,
 236                                             uint64_t SizeInBits,
 237                                             uint64_t AlignInBits,
 238                                             StringRef Name) {
 239   // FIXME: Why is there a name here?
 240   return DIDerivedType::get(VMContext, dwarf::DW_TAG_pointer_type, Name,
 241                             nullptr, 0, nullptr, DITypeRef::get(PointeeTy),
 242                             SizeInBits, AlignInBits, 0, 0);
 243 }
 244
 245 DIDerivedType *DIBuilder::createMemberPointerType(DIType *PointeeTy,
 246                                                   DIType *Base,
 247                                                   uint64_t SizeInBits,
 248                                                   uint64_t AlignInBits) {
 249   return DIDerivedType::get(VMContext, dwarf::DW_TAG_ptr_to_member_type, "",
 250                             nullptr, 0, nullptr, DITypeRef::get(PointeeTy),
 251                             SizeInBits, AlignInBits, 0, 0,
 252                             DITypeRef::get(Base));
 253 }
 254
 255 DIDerivedType *DIBuilder::createReferenceType(unsigned Tag, DIType *RTy) {
 256   assert(RTy && "Unable to create reference type");
 257   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr,
 258                             DITypeRef::get(RTy), 0, 0, 0, 0);
 259 }
 260
 261 DIDerivedType *DIBuilder::createTypedef(DIType *Ty, StringRef Name,
 262                                         DIFile *File, unsigned LineNo,
 263                                         DIScope *Context) {
 264   return DIDerivedType::get(VMContext, dwarf::DW_TAG_typedef, Name, File,
 265                             LineNo,
 266                             DIScopeRef::get(getNonCompileUnitScope(Context)),
 267                             DITypeRef::get(Ty), 0, 0, 0, 0);
 268 }
 269
 270 DIDerivedType *DIBuilder::createFriend(DIType *Ty, DIType *FriendTy) {
 271   assert(Ty && "Invalid type!");
 272   assert(FriendTy && "Invalid friend type!");
 273   return DIDerivedType::get(VMContext, dwarf::DW_TAG_friend, "", nullptr, 0,
 274                             DITypeRef::get(Ty), DITypeRef::get(FriendTy), 0, 0,
 275                             0, 0);
 276 }
 277
 278 DIDerivedType *DIBuilder::createInheritance(DIType *Ty, DIType *BaseTy,
 279                                             uint64_t BaseOffset,
 280                                             unsigned Flags) {
 281   assert(Ty && "Unable to create inheritance");
 282   return DIDerivedType::get(VMContext, dwarf::DW_TAG_inheritance, "", nullptr,
 283                             0, DITypeRef::get(Ty), DITypeRef::get(BaseTy), 0, 0,
 284                             BaseOffset, Flags);
 285 }
 286
 287 DIDerivedType *DIBuilder::createMemberType(DIScope *Scope, StringRef Name,
 288                                            DIFile *File, unsigned LineNumber,
 289                                            uint64_t SizeInBits,
 290                                            uint64_t AlignInBits,
 291                                            uint64_t OffsetInBits,
 292                                            unsigned Flags, DIType *Ty) {
 293   return DIDerivedType::get(
 294       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 295       DIScopeRef::get(getNonCompileUnitScope(Scope)), DITypeRef::get(Ty),
 296       SizeInBits, AlignInBits, OffsetInBits, Flags);
 297 }
 298
 299 static ConstantAsMetadata *getConstantOrNull(Constant *C) {
 300   if (C)
 301     return ConstantAsMetadata::get(C);
 302   return nullptr;
 303 }
 304
 305 DIDerivedType *DIBuilder::createStaticMemberType(DIScope *Scope, StringRef Name,
 306                                                  DIFile *File,
 307                                                  unsigned LineNumber,
 308                                                  DIType *Ty, unsigned Flags,
 309                                                  llvm::Constant *Val) {
 310   Flags |= DINode::FlagStaticMember;
 311   return DIDerivedType::get(
 312       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 313       DIScopeRef::get(getNonCompileUnitScope(Scope)), DITypeRef::get(Ty), 0, 0,
 314       0, Flags, getConstantOrNull(Val));
 315 }
 316
 317 DIDerivedType *DIBuilder::createObjCIVar(StringRef Name, DIFile *File,
 318                                          unsigned LineNumber,
 319                                          uint64_t SizeInBits,
 320                                          uint64_t AlignInBits,
 321                                          uint64_t OffsetInBits, unsigned Flags,
 322                                          DIType *Ty, MDNode *PropertyNode) {
 323   return DIDerivedType::get(
 324       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 325       DIScopeRef::get(getNonCompileUnitScope(File)), DITypeRef::get(Ty),
 326       SizeInBits, AlignInBits, OffsetInBits, Flags, PropertyNode);
 327 }
 328
 329 DIObjCProperty *
 330 DIBuilder::createObjCProperty(StringRef Name, DIFile *File, unsigned LineNumber,
 331                               StringRef GetterName, StringRef SetterName,
 332                               unsigned PropertyAttributes, DIType *Ty) {
 333   return DIObjCProperty::get(VMContext, Name, File, LineNumber, GetterName,
 334                              SetterName, PropertyAttributes,
 335                              DITypeRef::get(Ty));
 336 }
 337
 338 DITemplateTypeParameter *
 339 DIBuilder::createTemplateTypeParameter(DIScope *Context, StringRef Name,
 340                                        DIType *Ty) {
 341   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 342   return DITemplateTypeParameter::get(VMContext, Name, DITypeRef::get(Ty));
 343 }
 344
 345 static DITemplateValueParameter *
 346 createTemplateValueParameterHelper(LLVMContext &VMContext, unsigned Tag,
 347                                    DIScope *Context, StringRef Name, DIType *Ty,
 348                                    Metadata *MD) {
 349   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 350   return DITemplateValueParameter::get(VMContext, Tag, Name, DITypeRef::get(Ty),
 351                                        MD);
 352 }
 353
 354 DITemplateValueParameter *
 355 DIBuilder::createTemplateValueParameter(DIScope *Context, StringRef Name,
 356                                         DIType *Ty, Constant *Val) {
 357   return createTemplateValueParameterHelper(
 358       VMContext, dwarf::DW_TAG_template_value_parameter, Context, Name, Ty,
 359       getConstantOrNull(Val));
 360 }
 361
 362 DITemplateValueParameter *
 363 DIBuilder::createTemplateTemplateParameter(DIScope *Context, StringRef Name,
 364                                            DIType *Ty, StringRef Val) {
 365   return createTemplateValueParameterHelper(
 366       VMContext, dwarf::DW_TAG_GNU_template_template_param, Context, Name, Ty,
 367       MDString::get(VMContext, Val));
 368 }
 369
 370 DITemplateValueParameter *
 371 DIBuilder::createTemplateParameterPack(DIScope *Context, StringRef Name,
 372                                        DIType *Ty, DINodeArray Val) {
 373   return createTemplateValueParameterHelper(
 374       VMContext, dwarf::DW_TAG_GNU_template_parameter_pack, Context, Name, Ty,
 375       Val.get());
 376 }
 377
 378 DICompositeType *DIBuilder::createClassType(
 379     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 380     uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits,
 381     unsigned Flags, DIType *DerivedFrom, DINodeArray Elements,
 382     DIType *VTableHolder, MDNode *TemplateParams, StringRef UniqueIdentifier) {
 383   assert((!Context || isa<DIScope>(Context)) &&
 384          "createClassType should be called with a valid Context");
 385
 386   auto *R = DICompositeType::get(
 387       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 388       DIScopeRef::get(getNonCompileUnitScope(Context)),
 389       DITypeRef::get(DerivedFrom), SizeInBits, AlignInBits, OffsetInBits, Flags,
 390       Elements, 0, DITypeRef::get(VTableHolder),
 391       cast_or_null<MDTuple>(TemplateParams), UniqueIdentifier);
 392   if (!UniqueIdentifier.empty())
 393     retainType(R);
 394   trackIfUnresolved(R);
 395   return R;
 396 }
 397
 398 DICompositeType *DIBuilder::createStructType(
 399     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 400     uint64_t SizeInBits, uint64_t AlignInBits, unsigned Flags,
 401     DIType *DerivedFrom, DINodeArray Elements, unsigned RunTimeLang,
 402     DIType *VTableHolder, StringRef UniqueIdentifier) {
 403   auto *R = DICompositeType::get(
 404       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 405       DIScopeRef::get(getNonCompileUnitScope(Context)),
 406       DITypeRef::get(DerivedFrom), SizeInBits, AlignInBits, 0, Flags, Elements,
 407       RunTimeLang, DITypeRef::get(VTableHolder), nullptr, UniqueIdentifier);
 408   if (!UniqueIdentifier.empty())
 409     retainType(R);
 410   trackIfUnresolved(R);
 411   return R;
 412 }
 413
 414 DICompositeType *DIBuilder::createUnionType(
 415     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 416     uint64_t SizeInBits, uint64_t AlignInBits, unsigned Flags,
 417     DINodeArray Elements, unsigned RunTimeLang, StringRef UniqueIdentifier) {
 418   auto *R = DICompositeType::get(
 419       VMContext, dwarf::DW_TAG_union_type, Name, File, LineNumber,
 420       DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr, SizeInBits,
 421       AlignInBits, 0, Flags, Elements, RunTimeLang, nullptr, nullptr,
 422       UniqueIdentifier);
 423   if (!UniqueIdentifier.empty())
 424     retainType(R);
 425   trackIfUnresolved(R);
 426   return R;
 427 }
 428
 429 DISubroutineType *DIBuilder::createSubroutineType(DIFile *File,
 430                                                   DITypeRefArray ParameterTypes,
 431                                                   unsigned Flags) {
 432   return DISubroutineType::get(VMContext, Flags, ParameterTypes);
 433 }
 434
 435 DICompositeType *DIBuilder::createEnumerationType(
 436     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 437     uint64_t SizeInBits, uint64_t AlignInBits, DINodeArray Elements,
 438     DIType *UnderlyingType, StringRef UniqueIdentifier) {
 439   auto *CTy = DICompositeType::get(
 440       VMContext, dwarf::DW_TAG_enumeration_type, Name, File, LineNumber,
 441       DIScopeRef::get(getNonCompileUnitScope(Scope)),
 442       DITypeRef::get(UnderlyingType), SizeInBits, AlignInBits, 0, 0, Elements,
 443       0, nullptr, nullptr, UniqueIdentifier);
 444   AllEnumTypes.push_back(CTy);
 445   if (!UniqueIdentifier.empty())
 446     retainType(CTy);
 447   trackIfUnresolved(CTy);
 448   return CTy;
 449 }
 450
 451 DICompositeType *DIBuilder::createArrayType(uint64_t Size, uint64_t AlignInBits,
 452                                             DIType *Ty,
 453                                             DINodeArray Subscripts) {
 454   auto *R = DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "",
 455                                  nullptr, 0, nullptr, DITypeRef::get(Ty), Size,
 456                                  AlignInBits, 0, 0, Subscripts, 0, nullptr);
 457   trackIfUnresolved(R);
 458   return R;
 459 }
 460
 461 DICompositeType *DIBuilder::createVectorType(uint64_t Size,
 462                                              uint64_t AlignInBits, DIType *Ty,
 463                                              DINodeArray Subscripts) {
 464   auto *R =
 465       DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "", nullptr, 0,
 466                            nullptr, DITypeRef::get(Ty), Size, AlignInBits, 0,
 467                            DINode::FlagVector, Subscripts, 0, nullptr);
 468   trackIfUnresolved(R);
 469   return R;
 470 }
 471
 472 static DIType *createTypeWithFlags(LLVMContext &Context, DIType *Ty,
 473                                    unsigned FlagsToSet) {
 474   auto NewTy = Ty->clone();
 475   NewTy->setFlags(NewTy->getFlags() | FlagsToSet);
 476   return MDNode::replaceWithUniqued(std::move(NewTy));
 477 }
 478
 479 DIType *DIBuilder::createArtificialType(DIType *Ty) {
 480   // FIXME: Restrict this to the nodes where it's valid.
 481   if (Ty->isArtificial())
 482     return Ty;
 483   return createTypeWithFlags(VMContext, Ty, DINode::FlagArtificial);
 484 }
 485
 486 DIType *DIBuilder::createObjectPointerType(DIType *Ty) {
 487   // FIXME: Restrict this to the nodes where it's valid.
 488   if (Ty->isObjectPointer())
 489     return Ty;
 490   unsigned Flags = DINode::FlagObjectPointer | DINode::FlagArtificial;
 491   return createTypeWithFlags(VMContext, Ty, Flags);
 492 }
 493
 494 void DIBuilder::retainType(DIType *T) {
 495   assert(T && "Expected non-null type");
 496   AllRetainTypes.emplace_back(T);
 497 }
 498
 499 DIBasicType *DIBuilder::createUnspecifiedParameter() { return nullptr; }
 500
 501 DICompositeType *
 502 DIBuilder::createForwardDecl(unsigned Tag, StringRef Name, DIScope *Scope,
 503                              DIFile *F, unsigned Line, unsigned RuntimeLang,
 504                              uint64_t SizeInBits, uint64_t AlignInBits,
 505                              StringRef UniqueIdentifier) {
 506   // FIXME: Define in terms of createReplaceableForwardDecl() by calling
 507   // replaceWithUniqued().
 508   auto *RetTy = DICompositeType::get(
 509       VMContext, Tag, Name, F, Line,
 510       DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr, SizeInBits,
 511       AlignInBits, 0, DINode::FlagFwdDecl, nullptr, RuntimeLang, nullptr,
 512       nullptr, UniqueIdentifier);
 513   if (!UniqueIdentifier.empty())
 514     retainType(RetTy);
 515   trackIfUnresolved(RetTy);
 516   return RetTy;
 517 }
 518
 519 DICompositeType *DIBuilder::createReplaceableCompositeType(
 520     unsigned Tag, StringRef Name, DIScope *Scope, DIFile *F, unsigned Line,
 521     unsigned RuntimeLang, uint64_t SizeInBits, uint64_t AlignInBits,
 522     unsigned Flags, StringRef UniqueIdentifier) {
 523   auto *RetTy = DICompositeType::getTemporary(
 524                     VMContext, Tag, Name, F, Line,
 525                     DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr,
 526                     SizeInBits, AlignInBits, 0, Flags, nullptr, RuntimeLang,
 527                     nullptr, nullptr, UniqueIdentifier)
 528                     .release();
 529   if (!UniqueIdentifier.empty())
 530     retainType(RetTy);
 531   trackIfUnresolved(RetTy);
 532   return RetTy;
 533 }
 534
 535 DINodeArray DIBuilder::getOrCreateArray(ArrayRef<Metadata *> Elements) {
 536   return MDTuple::get(VMContext, Elements);
 537 }
 538
 539 DITypeRefArray DIBuilder::getOrCreateTypeArray(ArrayRef<Metadata *> Elements) {
 540   SmallVector<llvm::Metadata *, 16> Elts;
 541   for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
 542     if (Elements[i] && isa<MDNode>(Elements[i]))
 543       Elts.push_back(DITypeRef::get(cast<DIType>(Elements[i])));
 544     else
 545       Elts.push_back(Elements[i]);
 546   }
 547   return DITypeRefArray(MDNode::get(VMContext, Elts));
 548 }
 549
 550 DISubrange *DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Count) {
 551   return DISubrange::get(VMContext, Count, Lo);
 552 }
 553
 554 static void checkGlobalVariableScope(DIScope *Context) {
 555 #ifndef NDEBUG
 556   if (auto *CT =
 557           dyn_cast_or_null<DICompositeType>(getNonCompileUnitScope(Context)))
 558     assert(CT->getIdentifier().empty() &&
 559            "Context of a global variable should not be a type with identifier");
 560 #endif
 561 }
 562
 563 DIGlobalVariable *DIBuilder::createGlobalVariable(
 564     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 565     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, Constant *Val,
 566     MDNode *Decl) {
 567   checkGlobalVariableScope(Context);
 568
 569   auto *N = DIGlobalVariable::get(VMContext, cast_or_null<DIScope>(Context),
 570                                   Name, LinkageName, F, LineNumber,
 571                                   DITypeRef::get(Ty), isLocalToUnit, true, Val,
 572                                   cast_or_null<DIDerivedType>(Decl));
 573   AllGVs.push_back(N);
 574   return N;
 575 }
 576
 577 DIGlobalVariable *DIBuilder::createTempGlobalVariableFwdDecl(
 578     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 579     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, Constant *Val,
 580     MDNode *Decl) {
 581   checkGlobalVariableScope(Context);
 582
 583   return DIGlobalVariable::getTemporary(
 584              VMContext, cast_or_null<DIScope>(Context), Name, LinkageName, F,
 585              LineNumber, DITypeRef::get(Ty), isLocalToUnit, false, Val,
 586              cast_or_null<DIDerivedType>(Decl))
 587       .release();
 588 }
 589
 590 DILocalVariable *DIBuilder::createLocalVariable(
 591     unsigned Tag, DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNo,
 592     DIType *Ty, bool AlwaysPreserve, unsigned Flags, unsigned ArgNo) {
 593   // FIXME: Why getNonCompileUnitScope()?
 594   // FIXME: Why is "!Context" okay here?
 595   // FIXME: WHy doesn't this check for a subprogram or lexical block (AFAICT
 596   // the only valid scopes)?
 597   DIScope *Context = getNonCompileUnitScope(Scope);
 598
 599   auto *Node = DILocalVariable::get(
 600       VMContext, Tag, cast_or_null<DILocalScope>(Context), Name, File, LineNo,
 601       DITypeRef::get(Ty), ArgNo, Flags);
 602   if (AlwaysPreserve) {
 603     // The optimizer may remove local variable. If there is an interest
 604     // to preserve variable info in such situation then stash it in a
 605     // named mdnode.
 606     DISubprogram *Fn = getDISubprogram(Scope);
 607     assert(Fn && "Missing subprogram for local variable");
 608     PreservedVariables[Fn].emplace_back(Node);
 609   }
 610   return Node;
 611 }
 612
 613 DIExpression *DIBuilder::createExpression(ArrayRef<uint64_t> Addr) {
 614   return DIExpression::get(VMContext, Addr);
 615 }
 616
 617 DIExpression *DIBuilder::createExpression(ArrayRef<int64_t> Signed) {
 618   // TODO: Remove the callers of this signed version and delete.
 619   SmallVector<uint64_t, 8> Addr(Signed.begin(), Signed.end());
 620   return createExpression(Addr);
 621 }
 622
 623 DIExpression *DIBuilder::createBitPieceExpression(unsigned OffsetInBytes,
 624                                                   unsigned SizeInBytes) {
 625   uint64_t Addr[] = {dwarf::DW_OP_bit_piece, OffsetInBytes, SizeInBytes};
 626   return DIExpression::get(VMContext, Addr);
 627 }
 628
 629 DISubprogram *DIBuilder::createFunction(DIScopeRef Context, StringRef Name,
 630                                         StringRef LinkageName, DIFile *File,
 631                                         unsigned LineNo, DISubroutineType *Ty,
 632                                         bool isLocalToUnit, bool isDefinition,
 633                                         unsigned ScopeLine, unsigned Flags,
 634                                         bool isOptimized, Function *Fn,
 635                                         MDNode *TParams, MDNode *Decl) {
 636   // dragonegg does not generate identifier for types, so using an empty map
 637   // to resolve the context should be fine.
 638   DITypeIdentifierMap EmptyMap;
 639   return createFunction(Context.resolve(EmptyMap), Name, LinkageName, File,
 640                         LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine,
 641                         Flags, isOptimized, Fn, TParams, Decl);
 642 }
 643
 644 DISubprogram *DIBuilder::createFunction(DIScope *Context, StringRef Name,
 645                                         StringRef LinkageName, DIFile *File,
 646                                         unsigned LineNo, DISubroutineType *Ty,
 647                                         bool isLocalToUnit, bool isDefinition,
 648                                         unsigned ScopeLine, unsigned Flags,
 649                                         bool isOptimized, Function *Fn,
 650                                         MDNode *TParams, MDNode *Decl) {
 651   assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
 652          "function types should be subroutines");
 653   auto *Node = DISubprogram::get(
 654       VMContext, DIScopeRef::get(getNonCompileUnitScope(Context)), Name,
 655       LinkageName, File, LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine,
 656       nullptr, 0, 0, Flags, isOptimized, Fn, cast_or_null<MDTuple>(TParams),
 657       cast_or_null<DISubprogram>(Decl),
 658       MDTuple::getTemporary(VMContext, None).release());
 659
 660   if (isDefinition)
 661     AllSubprograms.push_back(Node);
 662   trackIfUnresolved(Node);
 663   return Node;
 664 }
 665
 666 DISubprogram *DIBuilder::createTempFunctionFwdDecl(
 667     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *File,
 668     unsigned LineNo, DISubroutineType *Ty, bool isLocalToUnit,
 669     bool isDefinition, unsigned ScopeLine, unsigned Flags, bool isOptimized,
 670     Function *Fn, MDNode *TParams, MDNode *Decl) {
 671   return DISubprogram::getTemporary(
 672              VMContext, DIScopeRef::get(getNonCompileUnitScope(Context)), Name,
 673              LinkageName, File, LineNo, Ty, isLocalToUnit, isDefinition,
 674              ScopeLine, nullptr, 0, 0, Flags, isOptimized, Fn,
 675              cast_or_null<MDTuple>(TParams), cast_or_null<DISubprogram>(Decl),
 676              nullptr)
 677       .release();
 678 }
 679
 680 DISubprogram *
 681 DIBuilder::createMethod(DIScope *Context, StringRef Name, StringRef LinkageName,
 682                         DIFile *F, unsigned LineNo, DISubroutineType *Ty,
 683                         bool isLocalToUnit, bool isDefinition, unsigned VK,
 684                         unsigned VIndex, DIType *VTableHolder, unsigned Flags,
 685                         bool isOptimized, Function *Fn, MDNode *TParam) {
 686   assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
 687          "function types should be subroutines");
 688   assert(getNonCompileUnitScope(Context) &&
 689          "Methods should have both a Context and a context that isn't "
 690          "the compile unit.");
 691   // FIXME: Do we want to use different scope/lines?
 692   auto *SP = DISubprogram::get(
 693       VMContext, DIScopeRef::get(cast<DIScope>(Context)), Name, LinkageName, F,
 694       LineNo, Ty, isLocalToUnit, isDefinition, LineNo,
 695       DITypeRef::get(VTableHolder), VK, VIndex, Flags, isOptimized, Fn,
 696       cast_or_null<MDTuple>(TParam), nullptr, nullptr);
 697
 698   if (isDefinition)
 699     AllSubprograms.push_back(SP);
 700   trackIfUnresolved(SP);
 701   return SP;
 702 }
 703
 704 DINamespace *DIBuilder::createNameSpace(DIScope *Scope, StringRef Name,
 705                                         DIFile *File, unsigned LineNo) {
 706   return DINamespace::get(VMContext, getNonCompileUnitScope(Scope), File, Name,
 707                           LineNo);
 708 }
 709
 710 DIModule *DIBuilder::createModule(DIScope *Scope, StringRef Name,
 711                                   StringRef ConfigurationMacros,
 712                                   StringRef IncludePath,
 713                                   StringRef ISysRoot) {
 714  return DIModule::get(VMContext, getNonCompileUnitScope(Scope), Name,
 715                       ConfigurationMacros, IncludePath, ISysRoot);
 716 }
 717
 718 DILexicalBlockFile *DIBuilder::createLexicalBlockFile(DIScope *Scope,
 719                                                       DIFile *File,
 720                                                       unsigned Discriminator) {
 721   return DILexicalBlockFile::get(VMContext, Scope, File, Discriminator);
 722 }
 723
 724 DILexicalBlock *DIBuilder::createLexicalBlock(DIScope *Scope, DIFile *File,
 725                                               unsigned Line, unsigned Col) {
 726   // Make these distinct, to avoid merging two lexical blocks on the same
 727   // file/line/column.
 728   return DILexicalBlock::getDistinct(VMContext, getNonCompileUnitScope(Scope),
 729                                      File, Line, Col);
 730 }
 731
 732 static Value *getDbgIntrinsicValueImpl(LLVMContext &VMContext, Value *V) {
 733   assert(V && "no value passed to dbg intrinsic");
 734   return MetadataAsValue::get(VMContext, ValueAsMetadata::get(V));
 735 }
 736
 737 static Instruction *withDebugLoc(Instruction *I, const DILocation *DL) {
 738   I->setDebugLoc(const_cast<DILocation *>(DL));
 739   return I;
 740 }
 741
 742 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 743                                       DIExpression *Expr, const DILocation *DL,
 744                                       Instruction *InsertBefore) {
 745   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
 746   assert(DL && "Expected debug loc");
 747   assert(DL->getScope()->getSubprogram() ==
 748              VarInfo->getScope()->getSubprogram() &&
 749          "Expected matching subprograms");
 750   if (!DeclareFn)
 751     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 752
 753   trackIfUnresolved(VarInfo);
 754   trackIfUnresolved(Expr);
 755   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
 756                    MetadataAsValue::get(VMContext, VarInfo),
 757                    MetadataAsValue::get(VMContext, Expr)};
 758   return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertBefore), DL);
 759 }
 760
 761 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 762                                       DIExpression *Expr, const DILocation *DL,
 763                                       BasicBlock *InsertAtEnd) {
 764   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
 765   assert(DL && "Expected debug loc");
 766   assert(DL->getScope()->getSubprogram() ==
 767              VarInfo->getScope()->getSubprogram() &&
 768          "Expected matching subprograms");
 769   if (!DeclareFn)
 770     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 771
 772   trackIfUnresolved(VarInfo);
 773   trackIfUnresolved(Expr);
 774   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
 775                    MetadataAsValue::get(VMContext, VarInfo),
 776                    MetadataAsValue::get(VMContext, Expr)};
 777
 778   // If this block already has a terminator then insert this intrinsic
 779   // before the terminator.
 780   if (TerminatorInst *T = InsertAtEnd->getTerminator())
 781     return withDebugLoc(CallInst::Create(DeclareFn, Args, "", T), DL);
 782   return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertAtEnd), DL);
 783 }
 784
 785 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
 786                                                 DILocalVariable *VarInfo,
 787                                                 DIExpression *Expr,
 788                                                 const DILocation *DL,
 789                                                 Instruction *InsertBefore) {
 790   assert(V && "no value passed to dbg.value");
 791   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
 792   assert(DL && "Expected debug loc");
 793   assert(DL->getScope()->getSubprogram() ==
 794              VarInfo->getScope()->getSubprogram() &&
 795          "Expected matching subprograms");
 796   if (!ValueFn)
 797     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
 798
 799   trackIfUnresolved(VarInfo);
 800   trackIfUnresolved(Expr);
 801   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
 802                    ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
 803                    MetadataAsValue::get(VMContext, VarInfo),
 804                    MetadataAsValue::get(VMContext, Expr)};
 805   return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertBefore), DL);
 806 }
 807
 808 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
 809                                                 DILocalVariable *VarInfo,
 810                                                 DIExpression *Expr,
 811                                                 const DILocation *DL,
 812                                                 BasicBlock *InsertAtEnd) {
 813   assert(V && "no value passed to dbg.value");
 814   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
 815   assert(DL && "Expected debug loc");
 816   assert(DL->getScope()->getSubprogram() ==
 817              VarInfo->getScope()->getSubprogram() &&
 818          "Expected matching subprograms");
 819   if (!ValueFn)
 820     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
 821
 822   trackIfUnresolved(VarInfo);
 823   trackIfUnresolved(Expr);
 824   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
 825                    ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
 826                    MetadataAsValue::get(VMContext, VarInfo),
 827                    MetadataAsValue::get(VMContext, Expr)};
 828
 829   return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertAtEnd), DL);
 830 }
 831
 832 void DIBuilder::replaceVTableHolder(DICompositeType *&T,
 833                                     DICompositeType *VTableHolder) {
 834   {
 835     TypedTrackingMDRef<DICompositeType> N(T);
 836     N->replaceVTableHolder(DITypeRef::get(VTableHolder));
 837     T = N.get();
 838   }
 839
 840   // If this didn't create a self-reference, just return.
 841   if (T != VTableHolder)
 842     return;
 843
 844   // Look for unresolved operands.  T will drop RAUW support, orphaning any
 845   // cycles underneath it.
 846   if (T->isResolved())
 847     for (const MDOperand &O : T->operands())
 848       if (auto *N = dyn_cast_or_null<MDNode>(O))
 849         trackIfUnresolved(N);
 850 }
 851
 852 void DIBuilder::replaceArrays(DICompositeType *&T, DINodeArray Elements,
 853                               DINodeArray TParams) {
 854   {
 855     TypedTrackingMDRef<DICompositeType> N(T);
 856     if (Elements)
 857       N->replaceElements(Elements);
 858     if (TParams)
 859       N->replaceTemplateParams(DITemplateParameterArray(TParams));
 860     T = N.get();
 861   }
 862
 863   // If T isn't resolved, there's no problem.
 864   if (!T->isResolved())
 865     return;
 866
 867   // If "T" is resolved, it may be due to a self-reference cycle.  Track the
 868   // arrays explicitly if they're unresolved, or else the cycles will be
 869   // orphaned.
 870   if (Elements)
 871     trackIfUnresolved(Elements.get());
 872   if (TParams)
 873     trackIfUnresolved(TParams.get());
 874 }