contrib/llvm/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/IR/IRBuilder.h"
  16 #include "LLVMContextImpl.h"
  17 #include "llvm/ADT/Optional.h"
  18 #include "llvm/ADT/STLExtras.h"
  19 #include "llvm/BinaryFormat/Dwarf.h"
  20 #include "llvm/IR/Constants.h"
  21 #include "llvm/IR/DebugInfo.h"
  22 #include "llvm/IR/IntrinsicInst.h"
  23 #include "llvm/IR/Module.h"
  24 #include "llvm/Support/Debug.h"
  25
  26 using namespace llvm;
  27 using namespace llvm::dwarf;
  28
  29 cl::opt<bool>
  30     UseDbgAddr("use-dbg-addr",
  31                llvm::cl::desc("Use llvm.dbg.addr for all local variables"),
  32                cl::init(false), cl::Hidden);
  33
  34 DIBuilder::DIBuilder(Module &m, bool AllowUnresolvedNodes, DICompileUnit *CU)
  35   : M(m), VMContext(M.getContext()), CUNode(CU),
  36       DeclareFn(nullptr), ValueFn(nullptr), LabelFn(nullptr),
  37       AllowUnresolvedNodes(AllowUnresolvedNodes) {}
  38
  39 void DIBuilder::trackIfUnresolved(MDNode *N) {
  40   if (!N)
  41     return;
  42   if (N->isResolved())
  43     return;
  44
  45   assert(AllowUnresolvedNodes && "Cannot handle unresolved nodes");
  46   UnresolvedNodes.emplace_back(N);
  47 }
  48
  49 void DIBuilder::finalizeSubprogram(DISubprogram *SP) {
  50   MDTuple *Temp = SP->getRetainedNodes().get();
  51   if (!Temp || !Temp->isTemporary())
  52     return;
  53
  54   SmallVector<Metadata *, 16> RetainedNodes;
  55
  56   auto PV = PreservedVariables.find(SP);
  57   if (PV != PreservedVariables.end())
  58     RetainedNodes.append(PV->second.begin(), PV->second.end());
  59
  60   auto PL = PreservedLabels.find(SP);
  61   if (PL != PreservedLabels.end())
  62     RetainedNodes.append(PL->second.begin(), PL->second.end());
  63
  64   DINodeArray Node = getOrCreateArray(RetainedNodes);
  65
  66   TempMDTuple(Temp)->replaceAllUsesWith(Node.get());
  67 }
  68
  69 void DIBuilder::finalize() {
  70   if (!CUNode) {
  71     assert(!AllowUnresolvedNodes &&
  72            "creating type nodes without a CU is not supported");
  73     return;
  74   }
  75
  76   CUNode->replaceEnumTypes(MDTuple::get(VMContext, AllEnumTypes));
  77
  78   SmallVector<Metadata *, 16> RetainValues;
  79   // Declarations and definitions of the same type may be retained. Some
  80   // clients RAUW these pairs, leaving duplicates in the retained types
  81   // list. Use a set to remove the duplicates while we transform the
  82   // TrackingVHs back into Values.
  83   SmallPtrSet<Metadata *, 16> RetainSet;
  84   for (unsigned I = 0, E = AllRetainTypes.size(); I < E; I++)
  85     if (RetainSet.insert(AllRetainTypes[I]).second)
  86       RetainValues.push_back(AllRetainTypes[I]);
  87
  88   if (!RetainValues.empty())
  89     CUNode->replaceRetainedTypes(MDTuple::get(VMContext, RetainValues));
  90
  91   DISubprogramArray SPs = MDTuple::get(VMContext, AllSubprograms);
  92   for (auto *SP : SPs)
  93     finalizeSubprogram(SP);
  94   for (auto *N : RetainValues)
  95     if (auto *SP = dyn_cast<DISubprogram>(N))
  96       finalizeSubprogram(SP);
  97
  98   if (!AllGVs.empty())
  99     CUNode->replaceGlobalVariables(MDTuple::get(VMContext, AllGVs));
 100
 101   if (!AllImportedModules.empty())
 102     CUNode->replaceImportedEntities(MDTuple::get(
 103         VMContext, SmallVector<Metadata *, 16>(AllImportedModules.begin(),
 104                                                AllImportedModules.end())));
 105
 106   for (const auto &I : AllMacrosPerParent) {
 107     // DIMacroNode's with nullptr parent are DICompileUnit direct children.
 108     if (!I.first) {
 109       CUNode->replaceMacros(MDTuple::get(VMContext, I.second.getArrayRef()));
 110       continue;
 111     }
 112     // Otherwise, it must be a temporary DIMacroFile that need to be resolved.
 113     auto *TMF = cast<DIMacroFile>(I.first);
 114     auto *MF = DIMacroFile::get(VMContext, dwarf::DW_MACINFO_start_file,
 115                                 TMF->getLine(), TMF->getFile(),
 116                                 getOrCreateMacroArray(I.second.getArrayRef()));
 117     replaceTemporary(llvm::TempDIMacroNode(TMF), MF);
 118   }
 119
 120   // Now that all temp nodes have been replaced or deleted, resolve remaining
 121   // cycles.
 122   for (const auto &N : UnresolvedNodes)
 123     if (N && !N->isResolved())
 124       N->resolveCycles();
 125   UnresolvedNodes.clear();
 126
 127   // Can't handle unresolved nodes anymore.
 128   AllowUnresolvedNodes = false;
 129 }
 130
 131 /// If N is compile unit return NULL otherwise return N.
 132 static DIScope *getNonCompileUnitScope(DIScope *N) {
 133   if (!N || isa<DICompileUnit>(N))
 134     return nullptr;
 135   return cast<DIScope>(N);
 136 }
 137
 138 DICompileUnit *DIBuilder::createCompileUnit(
 139     unsigned Lang, DIFile *File, StringRef Producer, bool isOptimized,
 140     StringRef Flags, unsigned RunTimeVer, StringRef SplitName,
 141     DICompileUnit::DebugEmissionKind Kind, uint64_t DWOId,
 142     bool SplitDebugInlining, bool DebugInfoForProfiling,
 143     DICompileUnit::DebugNameTableKind NameTableKind, bool RangesBaseAddress) {
 144
 145   assert(((Lang <= dwarf::DW_LANG_Fortran08 && Lang >= dwarf::DW_LANG_C89) ||
 146           (Lang <= dwarf::DW_LANG_hi_user && Lang >= dwarf::DW_LANG_lo_user)) &&
 147          "Invalid Language tag");
 148
 149   assert(!CUNode && "Can only make one compile unit per DIBuilder instance");
 150   CUNode = DICompileUnit::getDistinct(
 151       VMContext, Lang, File, Producer, isOptimized, Flags, RunTimeVer,
 152       SplitName, Kind, nullptr, nullptr, nullptr, nullptr, nullptr, DWOId,
 153       SplitDebugInlining, DebugInfoForProfiling, NameTableKind,
 154       RangesBaseAddress);
 155
 156   // Create a named metadata so that it is easier to find cu in a module.
 157   NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.cu");
 158   NMD->addOperand(CUNode);
 159   trackIfUnresolved(CUNode);
 160   return CUNode;
 161 }
 162
 163 static DIImportedEntity *
 164 createImportedModule(LLVMContext &C, dwarf::Tag Tag, DIScope *Context,
 165                      Metadata *NS, DIFile *File, unsigned Line, StringRef Name,
 166                      SmallVectorImpl<TrackingMDNodeRef> &AllImportedModules) {
 167   if (Line)
 168     assert(File && "Source location has line number but no file");
 169   unsigned EntitiesCount = C.pImpl->DIImportedEntitys.size();
 170   auto *M =
 171       DIImportedEntity::get(C, Tag, Context, DINodeRef(NS), File, Line, Name);
 172   if (EntitiesCount < C.pImpl->DIImportedEntitys.size())
 173     // A new Imported Entity was just added to the context.
 174     // Add it to the Imported Modules list.
 175     AllImportedModules.emplace_back(M);
 176   return M;
 177 }
 178
 179 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 180                                                   DINamespace *NS, DIFile *File,
 181                                                   unsigned Line) {
 182   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 183                                 Context, NS, File, Line, StringRef(),
 184                                 AllImportedModules);
 185 }
 186
 187 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 188                                                   DIImportedEntity *NS,
 189                                                   DIFile *File, unsigned Line) {
 190   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 191                                 Context, NS, File, Line, StringRef(),
 192                                 AllImportedModules);
 193 }
 194
 195 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context, DIModule *M,
 196                                                   DIFile *File, unsigned Line) {
 197   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 198                                 Context, M, File, Line, StringRef(),
 199                                 AllImportedModules);
 200 }
 201
 202 DIImportedEntity *DIBuilder::createImportedDeclaration(DIScope *Context,
 203                                                        DINode *Decl,
 204                                                        DIFile *File,
 205                                                        unsigned Line,
 206                                                        StringRef Name) {
 207   // Make sure to use the unique identifier based metadata reference for
 208   // types that have one.
 209   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_declaration,
 210                                 Context, Decl, File, Line, Name,
 211                                 AllImportedModules);
 212 }
 213
 214 DIFile *DIBuilder::createFile(StringRef Filename, StringRef Directory,
 215                               Optional<DIFile::ChecksumInfo<StringRef>> CS,
 216                               Optional<StringRef> Source) {
 217   return DIFile::get(VMContext, Filename, Directory, CS, Source);
 218 }
 219
 220 DIMacro *DIBuilder::createMacro(DIMacroFile *Parent, unsigned LineNumber,
 221                                 unsigned MacroType, StringRef Name,
 222                                 StringRef Value) {
 223   assert(!Name.empty() && "Unable to create macro without name");
 224   assert((MacroType == dwarf::DW_MACINFO_undef ||
 225           MacroType == dwarf::DW_MACINFO_define) &&
 226          "Unexpected macro type");
 227   auto *M = DIMacro::get(VMContext, MacroType, LineNumber, Name, Value);
 228   AllMacrosPerParent[Parent].insert(M);
 229   return M;
 230 }
 231
 232 DIMacroFile *DIBuilder::createTempMacroFile(DIMacroFile *Parent,
 233                                             unsigned LineNumber, DIFile *File) {
 234   auto *MF = DIMacroFile::getTemporary(VMContext, dwarf::DW_MACINFO_start_file,
 235                                        LineNumber, File, DIMacroNodeArray())
 236                  .release();
 237   AllMacrosPerParent[Parent].insert(MF);
 238   // Add the new temporary DIMacroFile to the macro per parent map as a parent.
 239   // This is needed to assure DIMacroFile with no children to have an entry in
 240   // the map. Otherwise, it will not be resolved in DIBuilder::finalize().
 241   AllMacrosPerParent.insert({MF, {}});
 242   return MF;
 243 }
 244
 245 DIEnumerator *DIBuilder::createEnumerator(StringRef Name, int64_t Val,
 246                                           bool IsUnsigned) {
 247   assert(!Name.empty() && "Unable to create enumerator without name");
 248   return DIEnumerator::get(VMContext, Val, IsUnsigned, Name);
 249 }
 250
 251 DIBasicType *DIBuilder::createUnspecifiedType(StringRef Name) {
 252   assert(!Name.empty() && "Unable to create type without name");
 253   return DIBasicType::get(VMContext, dwarf::DW_TAG_unspecified_type, Name);
 254 }
 255
 256 DIBasicType *DIBuilder::createNullPtrType() {
 257   return createUnspecifiedType("decltype(nullptr)");
 258 }
 259
 260 DIBasicType *DIBuilder::createBasicType(StringRef Name, uint64_t SizeInBits,
 261                                         unsigned Encoding,
 262                                         DINode::DIFlags Flags) {
 263   assert(!Name.empty() && "Unable to create type without name");
 264   return DIBasicType::get(VMContext, dwarf::DW_TAG_base_type, Name, SizeInBits,
 265                           0, Encoding, Flags);
 266 }
 267
 268 DIDerivedType *DIBuilder::createQualifiedType(unsigned Tag, DIType *FromTy) {
 269   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr, FromTy, 0,
 270                             0, 0, None, DINode::FlagZero);
 271 }
 272
 273 DIDerivedType *DIBuilder::createPointerType(
 274     DIType *PointeeTy,
 275     uint64_t SizeInBits,
 276     uint32_t AlignInBits,
 277     Optional<unsigned> DWARFAddressSpace,
 278     StringRef Name) {
 279   // FIXME: Why is there a name here?
 280   return DIDerivedType::get(VMContext, dwarf::DW_TAG_pointer_type, Name,
 281                             nullptr, 0, nullptr, PointeeTy, SizeInBits,
 282                             AlignInBits, 0, DWARFAddressSpace,
 283                             DINode::FlagZero);
 284 }
 285
 286 DIDerivedType *DIBuilder::createMemberPointerType(DIType *PointeeTy,
 287                                                   DIType *Base,
 288                                                   uint64_t SizeInBits,
 289                                                   uint32_t AlignInBits,
 290                                                   DINode::DIFlags Flags) {
 291   return DIDerivedType::get(VMContext, dwarf::DW_TAG_ptr_to_member_type, "",
 292                             nullptr, 0, nullptr, PointeeTy, SizeInBits,
 293                             AlignInBits, 0, None, Flags, Base);
 294 }
 295
 296 DIDerivedType *DIBuilder::createReferenceType(
 297     unsigned Tag, DIType *RTy,
 298     uint64_t SizeInBits,
 299     uint32_t AlignInBits,
 300     Optional<unsigned> DWARFAddressSpace) {
 301   assert(RTy && "Unable to create reference type");
 302   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr, RTy,
 303                             SizeInBits, AlignInBits, 0, DWARFAddressSpace,
 304                             DINode::FlagZero);
 305 }
 306
 307 DIDerivedType *DIBuilder::createTypedef(DIType *Ty, StringRef Name,
 308                                         DIFile *File, unsigned LineNo,
 309                                         DIScope *Context) {
 310   return DIDerivedType::get(VMContext, dwarf::DW_TAG_typedef, Name, File,
 311                             LineNo, getNonCompileUnitScope(Context), Ty, 0, 0,
 312                             0, None, DINode::FlagZero);
 313 }
 314
 315 DIDerivedType *DIBuilder::createFriend(DIType *Ty, DIType *FriendTy) {
 316   assert(Ty && "Invalid type!");
 317   assert(FriendTy && "Invalid friend type!");
 318   return DIDerivedType::get(VMContext, dwarf::DW_TAG_friend, "", nullptr, 0, Ty,
 319                             FriendTy, 0, 0, 0, None, DINode::FlagZero);
 320 }
 321
 322 DIDerivedType *DIBuilder::createInheritance(DIType *Ty, DIType *BaseTy,
 323                                             uint64_t BaseOffset,
 324                                             uint32_t VBPtrOffset,
 325                                             DINode::DIFlags Flags) {
 326   assert(Ty && "Unable to create inheritance");
 327   Metadata *ExtraData = ConstantAsMetadata::get(
 328       ConstantInt::get(IntegerType::get(VMContext, 32), VBPtrOffset));
 329   return DIDerivedType::get(VMContext, dwarf::DW_TAG_inheritance, "", nullptr,
 330                             0, Ty, BaseTy, 0, 0, BaseOffset, None,
 331                             Flags, ExtraData);
 332 }
 333
 334 DIDerivedType *DIBuilder::createMemberType(DIScope *Scope, StringRef Name,
 335                                            DIFile *File, unsigned LineNumber,
 336                                            uint64_t SizeInBits,
 337                                            uint32_t AlignInBits,
 338                                            uint64_t OffsetInBits,
 339                                            DINode::DIFlags Flags, DIType *Ty) {
 340   return DIDerivedType::get(VMContext, dwarf::DW_TAG_member, Name, File,
 341                             LineNumber, getNonCompileUnitScope(Scope), Ty,
 342                             SizeInBits, AlignInBits, OffsetInBits, None, Flags);
 343 }
 344
 345 static ConstantAsMetadata *getConstantOrNull(Constant *C) {
 346   if (C)
 347     return ConstantAsMetadata::get(C);
 348   return nullptr;
 349 }
 350
 351 DIDerivedType *DIBuilder::createVariantMemberType(
 352     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 353     uint64_t SizeInBits, uint32_t AlignInBits, uint64_t OffsetInBits,
 354     Constant *Discriminant, DINode::DIFlags Flags, DIType *Ty) {
 355   return DIDerivedType::get(VMContext, dwarf::DW_TAG_member, Name, File,
 356                             LineNumber, getNonCompileUnitScope(Scope), Ty,
 357                             SizeInBits, AlignInBits, OffsetInBits, None, Flags,
 358                             getConstantOrNull(Discriminant));
 359 }
 360
 361 DIDerivedType *DIBuilder::createBitFieldMemberType(
 362     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 363     uint64_t SizeInBits, uint64_t OffsetInBits, uint64_t StorageOffsetInBits,
 364     DINode::DIFlags Flags, DIType *Ty) {
 365   Flags |= DINode::FlagBitField;
 366   return DIDerivedType::get(
 367       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 368       getNonCompileUnitScope(Scope), Ty, SizeInBits, /* AlignInBits */ 0,
 369       OffsetInBits, None, Flags,
 370       ConstantAsMetadata::get(ConstantInt::get(IntegerType::get(VMContext, 64),
 371                                                StorageOffsetInBits)));
 372 }
 373
 374 DIDerivedType *
 375 DIBuilder::createStaticMemberType(DIScope *Scope, StringRef Name, DIFile *File,
 376                                   unsigned LineNumber, DIType *Ty,
 377                                   DINode::DIFlags Flags, llvm::Constant *Val,
 378                                   uint32_t AlignInBits) {
 379   Flags |= DINode::FlagStaticMember;
 380   return DIDerivedType::get(VMContext, dwarf::DW_TAG_member, Name, File,
 381                             LineNumber, getNonCompileUnitScope(Scope), Ty, 0,
 382                             AlignInBits, 0, None, Flags,
 383                             getConstantOrNull(Val));
 384 }
 385
 386 DIDerivedType *
 387 DIBuilder::createObjCIVar(StringRef Name, DIFile *File, unsigned LineNumber,
 388                           uint64_t SizeInBits, uint32_t AlignInBits,
 389                           uint64_t OffsetInBits, DINode::DIFlags Flags,
 390                           DIType *Ty, MDNode *PropertyNode) {
 391   return DIDerivedType::get(VMContext, dwarf::DW_TAG_member, Name, File,
 392                             LineNumber, getNonCompileUnitScope(File), Ty,
 393                             SizeInBits, AlignInBits, OffsetInBits, None, Flags,
 394                             PropertyNode);
 395 }
 396
 397 DIObjCProperty *
 398 DIBuilder::createObjCProperty(StringRef Name, DIFile *File, unsigned LineNumber,
 399                               StringRef GetterName, StringRef SetterName,
 400                               unsigned PropertyAttributes, DIType *Ty) {
 401   return DIObjCProperty::get(VMContext, Name, File, LineNumber, GetterName,
 402                              SetterName, PropertyAttributes, Ty);
 403 }
 404
 405 DITemplateTypeParameter *
 406 DIBuilder::createTemplateTypeParameter(DIScope *Context, StringRef Name,
 407                                        DIType *Ty) {
 408   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 409   return DITemplateTypeParameter::get(VMContext, Name, Ty);
 410 }
 411
 412 static DITemplateValueParameter *
 413 createTemplateValueParameterHelper(LLVMContext &VMContext, unsigned Tag,
 414                                    DIScope *Context, StringRef Name, DIType *Ty,
 415                                    Metadata *MD) {
 416   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 417   return DITemplateValueParameter::get(VMContext, Tag, Name, Ty, MD);
 418 }
 419
 420 DITemplateValueParameter *
 421 DIBuilder::createTemplateValueParameter(DIScope *Context, StringRef Name,
 422                                         DIType *Ty, Constant *Val) {
 423   return createTemplateValueParameterHelper(
 424       VMContext, dwarf::DW_TAG_template_value_parameter, Context, Name, Ty,
 425       getConstantOrNull(Val));
 426 }
 427
 428 DITemplateValueParameter *
 429 DIBuilder::createTemplateTemplateParameter(DIScope *Context, StringRef Name,
 430                                            DIType *Ty, StringRef Val) {
 431   return createTemplateValueParameterHelper(
 432       VMContext, dwarf::DW_TAG_GNU_template_template_param, Context, Name, Ty,
 433       MDString::get(VMContext, Val));
 434 }
 435
 436 DITemplateValueParameter *
 437 DIBuilder::createTemplateParameterPack(DIScope *Context, StringRef Name,
 438                                        DIType *Ty, DINodeArray Val) {
 439   return createTemplateValueParameterHelper(
 440       VMContext, dwarf::DW_TAG_GNU_template_parameter_pack, Context, Name, Ty,
 441       Val.get());
 442 }
 443
 444 DICompositeType *DIBuilder::createClassType(
 445     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 446     uint64_t SizeInBits, uint32_t AlignInBits, uint64_t OffsetInBits,
 447     DINode::DIFlags Flags, DIType *DerivedFrom, DINodeArray Elements,
 448     DIType *VTableHolder, MDNode *TemplateParams, StringRef UniqueIdentifier) {
 449   assert((!Context || isa<DIScope>(Context)) &&
 450          "createClassType should be called with a valid Context");
 451
 452   auto *R = DICompositeType::get(
 453       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 454       getNonCompileUnitScope(Context), DerivedFrom, SizeInBits, AlignInBits,
 455       OffsetInBits, Flags, Elements, 0, VTableHolder,
 456       cast_or_null<MDTuple>(TemplateParams), UniqueIdentifier);
 457   trackIfUnresolved(R);
 458   return R;
 459 }
 460
 461 DICompositeType *DIBuilder::createStructType(
 462     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 463     uint64_t SizeInBits, uint32_t AlignInBits, DINode::DIFlags Flags,
 464     DIType *DerivedFrom, DINodeArray Elements, unsigned RunTimeLang,
 465     DIType *VTableHolder, StringRef UniqueIdentifier) {
 466   auto *R = DICompositeType::get(
 467       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 468       getNonCompileUnitScope(Context), DerivedFrom, SizeInBits, AlignInBits, 0,
 469       Flags, Elements, RunTimeLang, VTableHolder, nullptr, UniqueIdentifier);
 470   trackIfUnresolved(R);
 471   return R;
 472 }
 473
 474 DICompositeType *DIBuilder::createUnionType(
 475     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 476     uint64_t SizeInBits, uint32_t AlignInBits, DINode::DIFlags Flags,
 477     DINodeArray Elements, unsigned RunTimeLang, StringRef UniqueIdentifier) {
 478   auto *R = DICompositeType::get(
 479       VMContext, dwarf::DW_TAG_union_type, Name, File, LineNumber,
 480       getNonCompileUnitScope(Scope), nullptr, SizeInBits, AlignInBits, 0, Flags,
 481       Elements, RunTimeLang, nullptr, nullptr, UniqueIdentifier);
 482   trackIfUnresolved(R);
 483   return R;
 484 }
 485
 486 DICompositeType *DIBuilder::createVariantPart(
 487     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 488     uint64_t SizeInBits, uint32_t AlignInBits, DINode::DIFlags Flags,
 489     DIDerivedType *Discriminator, DINodeArray Elements, StringRef UniqueIdentifier) {
 490   auto *R = DICompositeType::get(
 491       VMContext, dwarf::DW_TAG_variant_part, Name, File, LineNumber,
 492       getNonCompileUnitScope(Scope), nullptr, SizeInBits, AlignInBits, 0, Flags,
 493       Elements, 0, nullptr, nullptr, UniqueIdentifier, Discriminator);
 494   trackIfUnresolved(R);
 495   return R;
 496 }
 497
 498 DISubroutineType *DIBuilder::createSubroutineType(DITypeRefArray ParameterTypes,
 499                                                   DINode::DIFlags Flags,
 500                                                   unsigned CC) {
 501   return DISubroutineType::get(VMContext, Flags, CC, ParameterTypes);
 502 }
 503
 504 DICompositeType *DIBuilder::createEnumerationType(
 505     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 506     uint64_t SizeInBits, uint32_t AlignInBits, DINodeArray Elements,
 507     DIType *UnderlyingType, StringRef UniqueIdentifier, bool IsScoped) {
 508   auto *CTy = DICompositeType::get(
 509       VMContext, dwarf::DW_TAG_enumeration_type, Name, File, LineNumber,
 510       getNonCompileUnitScope(Scope), UnderlyingType, SizeInBits, AlignInBits, 0,
 511       IsScoped ? DINode::FlagEnumClass : DINode::FlagZero, Elements, 0, nullptr,
 512       nullptr, UniqueIdentifier);
 513   AllEnumTypes.push_back(CTy);
 514   trackIfUnresolved(CTy);
 515   return CTy;
 516 }
 517
 518 DICompositeType *DIBuilder::createArrayType(uint64_t Size,
 519                                             uint32_t AlignInBits, DIType *Ty,
 520                                             DINodeArray Subscripts) {
 521   auto *R = DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "",
 522                                  nullptr, 0, nullptr, Ty, Size, AlignInBits, 0,
 523                                  DINode::FlagZero, Subscripts, 0, nullptr);
 524   trackIfUnresolved(R);
 525   return R;
 526 }
 527
 528 DICompositeType *DIBuilder::createVectorType(uint64_t Size,
 529                                              uint32_t AlignInBits, DIType *Ty,
 530                                              DINodeArray Subscripts) {
 531   auto *R = DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "",
 532                                  nullptr, 0, nullptr, Ty, Size, AlignInBits, 0,
 533                                  DINode::FlagVector, Subscripts, 0, nullptr);
 534   trackIfUnresolved(R);
 535   return R;
 536 }
 537
 538 DISubprogram *DIBuilder::createArtificialSubprogram(DISubprogram *SP) {
 539   auto NewSP = SP->cloneWithFlags(SP->getFlags() | DINode::FlagArtificial);
 540   return MDNode::replaceWithDistinct(std::move(NewSP));
 541 }
 542
 543 static DIType *createTypeWithFlags(const DIType *Ty,
 544                                    DINode::DIFlags FlagsToSet) {
 545   auto NewTy = Ty->cloneWithFlags(Ty->getFlags() | FlagsToSet);
 546   return MDNode::replaceWithUniqued(std::move(NewTy));
 547 }
 548
 549 DIType *DIBuilder::createArtificialType(DIType *Ty) {
 550   // FIXME: Restrict this to the nodes where it's valid.
 551   if (Ty->isArtificial())
 552     return Ty;
 553   return createTypeWithFlags(Ty, DINode::FlagArtificial);
 554 }
 555
 556 DIType *DIBuilder::createObjectPointerType(DIType *Ty) {
 557   // FIXME: Restrict this to the nodes where it's valid.
 558   if (Ty->isObjectPointer())
 559     return Ty;
 560   DINode::DIFlags Flags = DINode::FlagObjectPointer | DINode::FlagArtificial;
 561   return createTypeWithFlags(Ty, Flags);
 562 }
 563
 564 void DIBuilder::retainType(DIScope *T) {
 565   assert(T && "Expected non-null type");
 566   assert((isa<DIType>(T) || (isa<DISubprogram>(T) &&
 567                              cast<DISubprogram>(T)->isDefinition() == false)) &&
 568          "Expected type or subprogram declaration");
 569   AllRetainTypes.emplace_back(T);
 570 }
 571
 572 DIBasicType *DIBuilder::createUnspecifiedParameter() { return nullptr; }
 573
 574 DICompositeType *
 575 DIBuilder::createForwardDecl(unsigned Tag, StringRef Name, DIScope *Scope,
 576                              DIFile *F, unsigned Line, unsigned RuntimeLang,
 577                              uint64_t SizeInBits, uint32_t AlignInBits,
 578                              StringRef UniqueIdentifier) {
 579   // FIXME: Define in terms of createReplaceableForwardDecl() by calling
 580   // replaceWithUniqued().
 581   auto *RetTy = DICompositeType::get(
 582       VMContext, Tag, Name, F, Line, getNonCompileUnitScope(Scope), nullptr,
 583       SizeInBits, AlignInBits, 0, DINode::FlagFwdDecl, nullptr, RuntimeLang,
 584       nullptr, nullptr, UniqueIdentifier);
 585   trackIfUnresolved(RetTy);
 586   return RetTy;
 587 }
 588
 589 DICompositeType *DIBuilder::createReplaceableCompositeType(
 590     unsigned Tag, StringRef Name, DIScope *Scope, DIFile *F, unsigned Line,
 591     unsigned RuntimeLang, uint64_t SizeInBits, uint32_t AlignInBits,
 592     DINode::DIFlags Flags, StringRef UniqueIdentifier) {
 593   auto *RetTy =
 594       DICompositeType::getTemporary(
 595           VMContext, Tag, Name, F, Line, getNonCompileUnitScope(Scope), nullptr,
 596           SizeInBits, AlignInBits, 0, Flags, nullptr, RuntimeLang, nullptr,
 597           nullptr, UniqueIdentifier)
 598           .release();
 599   trackIfUnresolved(RetTy);
 600   return RetTy;
 601 }
 602
 603 DINodeArray DIBuilder::getOrCreateArray(ArrayRef<Metadata *> Elements) {
 604   return MDTuple::get(VMContext, Elements);
 605 }
 606
 607 DIMacroNodeArray
 608 DIBuilder::getOrCreateMacroArray(ArrayRef<Metadata *> Elements) {
 609   return MDTuple::get(VMContext, Elements);
 610 }
 611
 612 DITypeRefArray DIBuilder::getOrCreateTypeArray(ArrayRef<Metadata *> Elements) {
 613   SmallVector<llvm::Metadata *, 16> Elts;
 614   for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
 615     if (Elements[i] && isa<MDNode>(Elements[i]))
 616       Elts.push_back(cast<DIType>(Elements[i]));
 617     else
 618       Elts.push_back(Elements[i]);
 619   }
 620   return DITypeRefArray(MDNode::get(VMContext, Elts));
 621 }
 622
 623 DISubrange *DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Count) {
 624   return DISubrange::get(VMContext, Count, Lo);
 625 }
 626
 627 DISubrange *DIBuilder::getOrCreateSubrange(int64_t Lo, Metadata *CountNode) {
 628   return DISubrange::get(VMContext, CountNode, Lo);
 629 }
 630
 631 static void checkGlobalVariableScope(DIScope *Context) {
 632 #ifndef NDEBUG
 633   if (auto *CT =
 634           dyn_cast_or_null<DICompositeType>(getNonCompileUnitScope(Context)))
 635     assert(CT->getIdentifier().empty() &&
 636            "Context of a global variable should not be a type with identifier");
 637 #endif
 638 }
 639
 640 DIGlobalVariableExpression *DIBuilder::createGlobalVariableExpression(
 641     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 642     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, DIExpression *Expr,
 643     MDNode *Decl, MDTuple *templateParams, uint32_t AlignInBits) {
 644   checkGlobalVariableScope(Context);
 645
 646   auto *GV = DIGlobalVariable::getDistinct(
 647       VMContext, cast_or_null<DIScope>(Context), Name, LinkageName, F,
 648       LineNumber, Ty, isLocalToUnit, true, cast_or_null<DIDerivedType>(Decl),
 649       templateParams, AlignInBits);
 650   if (!Expr)
 651     Expr = createExpression();
 652   auto *N = DIGlobalVariableExpression::get(VMContext, GV, Expr);
 653   AllGVs.push_back(N);
 654   return N;
 655 }
 656
 657 DIGlobalVariable *DIBuilder::createTempGlobalVariableFwdDecl(
 658     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 659     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, MDNode *Decl,
 660     MDTuple *templateParams, uint32_t AlignInBits) {
 661   checkGlobalVariableScope(Context);
 662
 663   return DIGlobalVariable::getTemporary(
 664              VMContext, cast_or_null<DIScope>(Context), Name, LinkageName, F,
 665              LineNumber, Ty, isLocalToUnit, false,
 666              cast_or_null<DIDerivedType>(Decl), templateParams, AlignInBits)
 667       .release();
 668 }
 669
 670 static DILocalVariable *createLocalVariable(
 671     LLVMContext &VMContext,
 672     DenseMap<MDNode *, SmallVector<TrackingMDNodeRef, 1>> &PreservedVariables,
 673     DIScope *Scope, StringRef Name, unsigned ArgNo, DIFile *File,
 674     unsigned LineNo, DIType *Ty, bool AlwaysPreserve, DINode::DIFlags Flags,
 675     uint32_t AlignInBits) {
 676   // FIXME: Why getNonCompileUnitScope()?
 677   // FIXME: Why is "!Context" okay here?
 678   // FIXME: Why doesn't this check for a subprogram or lexical block (AFAICT
 679   // the only valid scopes)?
 680   DIScope *Context = getNonCompileUnitScope(Scope);
 681
 682   auto *Node =
 683       DILocalVariable::get(VMContext, cast_or_null<DILocalScope>(Context), Name,
 684                            File, LineNo, Ty, ArgNo, Flags, AlignInBits);
 685   if (AlwaysPreserve) {
 686     // The optimizer may remove local variables. If there is an interest
 687     // to preserve variable info in such situation then stash it in a
 688     // named mdnode.
 689     DISubprogram *Fn = getDISubprogram(Scope);
 690     assert(Fn && "Missing subprogram for local variable");
 691     PreservedVariables[Fn].emplace_back(Node);
 692   }
 693   return Node;
 694 }
 695
 696 DILocalVariable *DIBuilder::createAutoVariable(DIScope *Scope, StringRef Name,
 697                                                DIFile *File, unsigned LineNo,
 698                                                DIType *Ty, bool AlwaysPreserve,
 699                                                DINode::DIFlags Flags,
 700                                                uint32_t AlignInBits) {
 701   return createLocalVariable(VMContext, PreservedVariables, Scope, Name,
 702                              /* ArgNo */ 0, File, LineNo, Ty, AlwaysPreserve,
 703                              Flags, AlignInBits);
 704 }
 705
 706 DILocalVariable *DIBuilder::createParameterVariable(
 707     DIScope *Scope, StringRef Name, unsigned ArgNo, DIFile *File,
 708     unsigned LineNo, DIType *Ty, bool AlwaysPreserve, DINode::DIFlags Flags) {
 709   assert(ArgNo && "Expected non-zero argument number for parameter");
 710   return createLocalVariable(VMContext, PreservedVariables, Scope, Name, ArgNo,
 711                              File, LineNo, Ty, AlwaysPreserve, Flags,
 712                              /* AlignInBits */0);
 713 }
 714
 715 DILabel *DIBuilder::createLabel(
 716     DIScope *Scope, StringRef Name, DIFile *File,
 717     unsigned LineNo, bool AlwaysPreserve) {
 718   DIScope *Context = getNonCompileUnitScope(Scope);
 719
 720   auto *Node =
 721       DILabel::get(VMContext, cast_or_null<DILocalScope>(Context), Name,
 722                    File, LineNo);
 723
 724   if (AlwaysPreserve) {
 725     /// The optimizer may remove labels. If there is an interest
 726     /// to preserve label info in such situation then append it to
 727     /// the list of retained nodes of the DISubprogram.
 728     DISubprogram *Fn = getDISubprogram(Scope);
 729     assert(Fn && "Missing subprogram for label");
 730     PreservedLabels[Fn].emplace_back(Node);
 731   }
 732   return Node;
 733 }
 734
 735 DIExpression *DIBuilder::createExpression(ArrayRef<uint64_t> Addr) {
 736   return DIExpression::get(VMContext, Addr);
 737 }
 738
 739 DIExpression *DIBuilder::createExpression(ArrayRef<int64_t> Signed) {
 740   // TODO: Remove the callers of this signed version and delete.
 741   SmallVector<uint64_t, 8> Addr(Signed.begin(), Signed.end());
 742   return createExpression(Addr);
 743 }
 744
 745 template <class... Ts>
 746 static DISubprogram *getSubprogram(bool IsDistinct, Ts &&... Args) {
 747   if (IsDistinct)
 748     return DISubprogram::getDistinct(std::forward<Ts>(Args)...);
 749   return DISubprogram::get(std::forward<Ts>(Args)...);
 750 }
 751
 752 DISubprogram *DIBuilder::createFunction(
 753     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *File,
 754     unsigned LineNo, DISubroutineType *Ty, unsigned ScopeLine,
 755     DINode::DIFlags Flags, DISubprogram::DISPFlags SPFlags,
 756     DITemplateParameterArray TParams, DISubprogram *Decl,
 757     DITypeArray ThrownTypes) {
 758   bool IsDefinition = SPFlags & DISubprogram::SPFlagDefinition;
 759   auto *Node = getSubprogram(
 760       /*IsDistinct=*/IsDefinition, VMContext, getNonCompileUnitScope(Context),
 761       Name, LinkageName, File, LineNo, Ty, ScopeLine, nullptr, 0, 0, Flags,
 762       SPFlags, IsDefinition ? CUNode : nullptr, TParams, Decl,
 763       MDTuple::getTemporary(VMContext, None).release(), ThrownTypes);
 764
 765   if (IsDefinition)
 766     AllSubprograms.push_back(Node);
 767   trackIfUnresolved(Node);
 768   return Node;
 769 }
 770
 771 DISubprogram *DIBuilder::createTempFunctionFwdDecl(
 772     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *File,
 773     unsigned LineNo, DISubroutineType *Ty, unsigned ScopeLine,
 774     DINode::DIFlags Flags, DISubprogram::DISPFlags SPFlags,
 775     DITemplateParameterArray TParams, DISubprogram *Decl,
 776     DITypeArray ThrownTypes) {
 777   bool IsDefinition = SPFlags & DISubprogram::SPFlagDefinition;
 778   return DISubprogram::getTemporary(VMContext, getNonCompileUnitScope(Context),
 779                                     Name, LinkageName, File, LineNo, Ty,
 780                                     ScopeLine, nullptr, 0, 0, Flags, SPFlags,
 781                                     IsDefinition ? CUNode : nullptr, TParams,
 782                                     Decl, nullptr, ThrownTypes)
 783       .release();
 784 }
 785
 786 DISubprogram *DIBuilder::createMethod(
 787     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 788     unsigned LineNo, DISubroutineType *Ty, unsigned VIndex, int ThisAdjustment,
 789     DIType *VTableHolder, DINode::DIFlags Flags,
 790     DISubprogram::DISPFlags SPFlags, DITemplateParameterArray TParams,
 791     DITypeArray ThrownTypes) {
 792   assert(getNonCompileUnitScope(Context) &&
 793          "Methods should have both a Context and a context that isn't "
 794          "the compile unit.");
 795   // FIXME: Do we want to use different scope/lines?
 796   bool IsDefinition = SPFlags & DISubprogram::SPFlagDefinition;
 797   auto *SP = getSubprogram(
 798       /*IsDistinct=*/IsDefinition, VMContext, cast<DIScope>(Context), Name,
 799       LinkageName, F, LineNo, Ty, LineNo, VTableHolder, VIndex, ThisAdjustment,
 800       Flags, SPFlags, IsDefinition ? CUNode : nullptr, TParams, nullptr,
 801       nullptr, ThrownTypes);
 802
 803   if (IsDefinition)
 804     AllSubprograms.push_back(SP);
 805   trackIfUnresolved(SP);
 806   return SP;
 807 }
 808
 809 DINamespace *DIBuilder::createNameSpace(DIScope *Scope, StringRef Name,
 810                                         bool ExportSymbols) {
 811
 812   // It is okay to *not* make anonymous top-level namespaces distinct, because
 813   // all nodes that have an anonymous namespace as their parent scope are
 814   // guaranteed to be unique and/or are linked to their containing
 815   // DICompileUnit. This decision is an explicit tradeoff of link time versus
 816   // memory usage versus code simplicity and may get revisited in the future.
 817   return DINamespace::get(VMContext, getNonCompileUnitScope(Scope), Name,
 818                           ExportSymbols);
 819 }
 820
 821 DIModule *DIBuilder::createModule(DIScope *Scope, StringRef Name,
 822                                   StringRef ConfigurationMacros,
 823                                   StringRef IncludePath,
 824                                   StringRef ISysRoot) {
 825  return DIModule::get(VMContext, getNonCompileUnitScope(Scope), Name,
 826                       ConfigurationMacros, IncludePath, ISysRoot);
 827 }
 828
 829 DILexicalBlockFile *DIBuilder::createLexicalBlockFile(DIScope *Scope,
 830                                                       DIFile *File,
 831                                                       unsigned Discriminator) {
 832   return DILexicalBlockFile::get(VMContext, Scope, File, Discriminator);
 833 }
 834
 835 DILexicalBlock *DIBuilder::createLexicalBlock(DIScope *Scope, DIFile *File,
 836                                               unsigned Line, unsigned Col) {
 837   // Make these distinct, to avoid merging two lexical blocks on the same
 838   // file/line/column.
 839   return DILexicalBlock::getDistinct(VMContext, getNonCompileUnitScope(Scope),
 840                                      File, Line, Col);
 841 }
 842
 843 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 844                                       DIExpression *Expr, const DILocation *DL,
 845                                       Instruction *InsertBefore) {
 846   return insertDeclare(Storage, VarInfo, Expr, DL, InsertBefore->getParent(),
 847                        InsertBefore);
 848 }
 849
 850 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 851                                       DIExpression *Expr, const DILocation *DL,
 852                                       BasicBlock *InsertAtEnd) {
 853   // If this block already has a terminator then insert this intrinsic before
 854   // the terminator. Otherwise, put it at the end of the block.
 855   Instruction *InsertBefore = InsertAtEnd->getTerminator();
 856   return insertDeclare(Storage, VarInfo, Expr, DL, InsertAtEnd, InsertBefore);
 857 }
 858
 859 Instruction *DIBuilder::insertLabel(DILabel *LabelInfo, const DILocation *DL,
 860                                     Instruction *InsertBefore) {
 861   return insertLabel(
 862       LabelInfo, DL, InsertBefore ? InsertBefore->getParent() : nullptr,
 863       InsertBefore);
 864 }
 865
 866 Instruction *DIBuilder::insertLabel(DILabel *LabelInfo, const DILocation *DL,
 867                                     BasicBlock *InsertAtEnd) {
 868   return insertLabel(LabelInfo, DL, InsertAtEnd, nullptr);
 869 }
 870
 871 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V,
 872                                                 DILocalVariable *VarInfo,
 873                                                 DIExpression *Expr,
 874                                                 const DILocation *DL,
 875                                                 Instruction *InsertBefore) {
 876   return insertDbgValueIntrinsic(
 877       V, VarInfo, Expr, DL, InsertBefore ? InsertBefore->getParent() : nullptr,
 878       InsertBefore);
 879 }
 880
 881 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V,
 882                                                 DILocalVariable *VarInfo,
 883                                                 DIExpression *Expr,
 884                                                 const DILocation *DL,
 885                                                 BasicBlock *InsertAtEnd) {
 886   return insertDbgValueIntrinsic(V, VarInfo, Expr, DL, InsertAtEnd, nullptr);
 887 }
 888
 889 /// Return an IRBuilder for inserting dbg.declare and dbg.value intrinsics. This
 890 /// abstracts over the various ways to specify an insert position.
 891 static IRBuilder<> getIRBForDbgInsertion(const DILocation *DL,
 892                                          BasicBlock *InsertBB,
 893                                          Instruction *InsertBefore) {
 894   IRBuilder<> B(DL->getContext());
 895   if (InsertBefore)
 896     B.SetInsertPoint(InsertBefore);
 897   else if (InsertBB)
 898     B.SetInsertPoint(InsertBB);
 899   B.SetCurrentDebugLocation(DL);
 900   return B;
 901 }
 902
 903 static Value *getDbgIntrinsicValueImpl(LLVMContext &VMContext, Value *V) {
 904   assert(V && "no value passed to dbg intrinsic");
 905   return MetadataAsValue::get(VMContext, ValueAsMetadata::get(V));
 906 }
 907
 908 static Function *getDeclareIntrin(Module &M) {
 909   return Intrinsic::getDeclaration(&M, UseDbgAddr ? Intrinsic::dbg_addr
 910                                                   : Intrinsic::dbg_declare);
 911 }
 912
 913 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 914                                       DIExpression *Expr, const DILocation *DL,
 915                                       BasicBlock *InsertBB, Instruction *InsertBefore) {
 916   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
 917   assert(DL && "Expected debug loc");
 918   assert(DL->getScope()->getSubprogram() ==
 919              VarInfo->getScope()->getSubprogram() &&
 920          "Expected matching subprograms");
 921   if (!DeclareFn)
 922     DeclareFn = getDeclareIntrin(M);
 923
 924   trackIfUnresolved(VarInfo);
 925   trackIfUnresolved(Expr);
 926   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
 927                    MetadataAsValue::get(VMContext, VarInfo),
 928                    MetadataAsValue::get(VMContext, Expr)};
 929
 930   IRBuilder<> B = getIRBForDbgInsertion(DL, InsertBB, InsertBefore);
 931   return B.CreateCall(DeclareFn, Args);
 932 }
 933
 934 Instruction *DIBuilder::insertDbgValueIntrinsic(
 935     Value *V, DILocalVariable *VarInfo, DIExpression *Expr,
 936     const DILocation *DL, BasicBlock *InsertBB, Instruction *InsertBefore) {
 937   assert(V && "no value passed to dbg.value");
 938   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
 939   assert(DL && "Expected debug loc");
 940   assert(DL->getScope()->getSubprogram() ==
 941              VarInfo->getScope()->getSubprogram() &&
 942          "Expected matching subprograms");
 943   if (!ValueFn)
 944     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
 945
 946   trackIfUnresolved(VarInfo);
 947   trackIfUnresolved(Expr);
 948   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
 949                    MetadataAsValue::get(VMContext, VarInfo),
 950                    MetadataAsValue::get(VMContext, Expr)};
 951
 952   IRBuilder<> B = getIRBForDbgInsertion(DL, InsertBB, InsertBefore);
 953   return B.CreateCall(ValueFn, Args);
 954 }
 955
 956 Instruction *DIBuilder::insertLabel(
 957     DILabel *LabelInfo, const DILocation *DL,
 958     BasicBlock *InsertBB, Instruction *InsertBefore) {
 959   assert(LabelInfo && "empty or invalid DILabel* passed to dbg.label");
 960   assert(DL && "Expected debug loc");
 961   assert(DL->getScope()->getSubprogram() ==
 962              LabelInfo->getScope()->getSubprogram() &&
 963          "Expected matching subprograms");
 964   if (!LabelFn)
 965     LabelFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_label);
 966
 967   trackIfUnresolved(LabelInfo);
 968   Value *Args[] = {MetadataAsValue::get(VMContext, LabelInfo)};
 969
 970   IRBuilder<> B = getIRBForDbgInsertion(DL, InsertBB, InsertBefore);
 971   return B.CreateCall(LabelFn, Args);
 972 }
 973
 974 void DIBuilder::replaceVTableHolder(DICompositeType *&T,
 975                                     DIType *VTableHolder) {
 976   {
 977     TypedTrackingMDRef<DICompositeType> N(T);
 978     N->replaceVTableHolder(VTableHolder);
 979     T = N.get();
 980   }
 981
 982   // If this didn't create a self-reference, just return.
 983   if (T != VTableHolder)
 984     return;
 985
 986   // Look for unresolved operands.  T will drop RAUW support, orphaning any
 987   // cycles underneath it.
 988   if (T->isResolved())
 989     for (const MDOperand &O : T->operands())
 990       if (auto *N = dyn_cast_or_null<MDNode>(O))
 991         trackIfUnresolved(N);
 992 }
 993
 994 void DIBuilder::replaceArrays(DICompositeType *&T, DINodeArray Elements,
 995                               DINodeArray TParams) {
 996   {
 997     TypedTrackingMDRef<DICompositeType> N(T);
 998     if (Elements)
 999       N->replaceElements(Elements);
1000     if (TParams)
1001       N->replaceTemplateParams(DITemplateParameterArray(TParams));
1002     T = N.get();
1003   }
1004
1005   // If T isn't resolved, there's no problem.
1006   if (!T->isResolved())
1007     return;
1008
1009   // If T is resolved, it may be due to a self-reference cycle.  Track the
1010   // arrays explicitly if they're unresolved, or else the cycles will be
1011   // orphaned.
1012   if (Elements)
1013     trackIfUnresolved(Elements.get());
1014   if (TParams)
1015     trackIfUnresolved(TParams.get());
1016 }