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 #include "LLVMContextImpl.h"
  23
  24 using namespace llvm;
  25 using namespace llvm::dwarf;
  26
  27 DIBuilder::DIBuilder(Module &m, bool AllowUnresolvedNodes)
  28   : M(m), VMContext(M.getContext()), CUNode(nullptr),
  29       DeclareFn(nullptr), ValueFn(nullptr),
  30       AllowUnresolvedNodes(AllowUnresolvedNodes) {}
  31
  32 void DIBuilder::trackIfUnresolved(MDNode *N) {
  33   if (!N)
  34     return;
  35   if (N->isResolved())
  36     return;
  37
  38   assert(AllowUnresolvedNodes && "Cannot handle unresolved nodes");
  39   UnresolvedNodes.emplace_back(N);
  40 }
  41
  42 void DIBuilder::finalize() {
  43   if (!CUNode) {
  44     assert(!AllowUnresolvedNodes &&
  45            "creating type nodes without a CU is not supported");
  46     return;
  47   }
  48
  49   CUNode->replaceEnumTypes(MDTuple::get(VMContext, AllEnumTypes));
  50
  51   SmallVector<Metadata *, 16> RetainValues;
  52   // Declarations and definitions of the same type may be retained. Some
  53   // clients RAUW these pairs, leaving duplicates in the retained types
  54   // list. Use a set to remove the duplicates while we transform the
  55   // TrackingVHs back into Values.
  56   SmallPtrSet<Metadata *, 16> RetainSet;
  57   for (unsigned I = 0, E = AllRetainTypes.size(); I < E; I++)
  58     if (RetainSet.insert(AllRetainTypes[I]).second)
  59       RetainValues.push_back(AllRetainTypes[I]);
  60
  61   if (!RetainValues.empty())
  62     CUNode->replaceRetainedTypes(MDTuple::get(VMContext, RetainValues));
  63
  64   DISubprogramArray SPs = MDTuple::get(VMContext, AllSubprograms);
  65   auto resolveVariables = [&](DISubprogram *SP) {
  66     MDTuple *Temp = SP->getVariables().get();
  67     if (!Temp)
  68       return;
  69
  70     SmallVector<Metadata *, 4> Variables;
  71
  72     auto PV = PreservedVariables.find(SP);
  73     if (PV != PreservedVariables.end())
  74       Variables.append(PV->second.begin(), PV->second.end());
  75
  76     DINodeArray AV = getOrCreateArray(Variables);
  77     TempMDTuple(Temp)->replaceAllUsesWith(AV.get());
  78   };
  79   for (auto *SP : SPs)
  80     resolveVariables(SP);
  81   for (auto *N : RetainValues)
  82     if (auto *SP = dyn_cast<DISubprogram>(N))
  83       resolveVariables(SP);
  84
  85   if (!AllGVs.empty())
  86     CUNode->replaceGlobalVariables(MDTuple::get(VMContext, AllGVs));
  87
  88   if (!AllImportedModules.empty())
  89     CUNode->replaceImportedEntities(MDTuple::get(
  90         VMContext, SmallVector<Metadata *, 16>(AllImportedModules.begin(),
  91                                                AllImportedModules.end())));
  92
  93   for (const auto &I : AllMacrosPerParent) {
  94     // DIMacroNode's with nullptr parent are DICompileUnit direct children.
  95     if (!I.first) {
  96       CUNode->replaceMacros(MDTuple::get(VMContext, I.second.getArrayRef()));
  97       continue;
  98     }
  99     // Otherwise, it must be a temporary DIMacroFile that need to be resolved.
 100     auto *TMF = cast<DIMacroFile>(I.first);
 101     auto *MF = DIMacroFile::get(VMContext, dwarf::DW_MACINFO_start_file,
 102                                 TMF->getLine(), TMF->getFile(),
 103                                 getOrCreateMacroArray(I.second.getArrayRef()));
 104     replaceTemporary(llvm::TempDIMacroNode(TMF), MF);
 105   }
 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, DIFile *File, StringRef Producer, bool isOptimized,
 127     StringRef Flags, unsigned RunTimeVer, StringRef SplitName,
 128     DICompileUnit::DebugEmissionKind Kind, uint64_t DWOId,
 129     bool SplitDebugInlining, bool DebugInfoForProfiling) {
 130
 131   assert(((Lang <= dwarf::DW_LANG_Fortran08 && Lang >= dwarf::DW_LANG_C89) ||
 132           (Lang <= dwarf::DW_LANG_hi_user && Lang >= dwarf::DW_LANG_lo_user)) &&
 133          "Invalid Language tag");
 134
 135   assert(!CUNode && "Can only make one compile unit per DIBuilder instance");
 136   CUNode = DICompileUnit::getDistinct(
 137       VMContext, Lang, File, Producer, isOptimized, Flags, RunTimeVer,
 138       SplitName, Kind, nullptr, nullptr, nullptr, nullptr, nullptr, DWOId,
 139       SplitDebugInlining, DebugInfoForProfiling);
 140
 141   // Create a named metadata so that it is easier to find cu in a module.
 142   NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.cu");
 143   NMD->addOperand(CUNode);
 144   trackIfUnresolved(CUNode);
 145   return CUNode;
 146 }
 147
 148 static DIImportedEntity *
 149 createImportedModule(LLVMContext &C, dwarf::Tag Tag, DIScope *Context,
 150                      Metadata *NS, unsigned Line, StringRef Name,
 151                      SmallVectorImpl<TrackingMDNodeRef> &AllImportedModules) {
 152   unsigned EntitiesCount = C.pImpl->DIImportedEntitys.size();
 153   auto *M = DIImportedEntity::get(C, Tag, Context, DINodeRef(NS), Line, Name);
 154   if (EntitiesCount < C.pImpl->DIImportedEntitys.size())
 155     // A new Imported Entity was just added to the context.
 156     // Add it to the Imported Modules list.
 157     AllImportedModules.emplace_back(M);
 158   return M;
 159 }
 160
 161 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 162                                                   DINamespace *NS,
 163                                                   unsigned Line) {
 164   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 165                                 Context, NS, Line, StringRef(), AllImportedModules);
 166 }
 167
 168 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 169                                                   DIImportedEntity *NS,
 170                                                   unsigned Line) {
 171   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 172                                 Context, NS, Line, StringRef(), AllImportedModules);
 173 }
 174
 175 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context, DIModule *M,
 176                                                   unsigned Line) {
 177   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 178                                 Context, M, Line, StringRef(), AllImportedModules);
 179 }
 180
 181 DIImportedEntity *DIBuilder::createImportedDeclaration(DIScope *Context,
 182                                                        DINode *Decl,
 183                                                        unsigned Line,
 184                                                        StringRef Name) {
 185   // Make sure to use the unique identifier based metadata reference for
 186   // types that have one.
 187   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_declaration,
 188                                 Context, Decl, Line, Name, AllImportedModules);
 189 }
 190
 191 DIFile *DIBuilder::createFile(StringRef Filename, StringRef Directory,
 192                               DIFile::ChecksumKind CSKind, StringRef Checksum) {
 193   return DIFile::get(VMContext, Filename, Directory, CSKind, Checksum);
 194 }
 195
 196 DIMacro *DIBuilder::createMacro(DIMacroFile *Parent, unsigned LineNumber,
 197                                 unsigned MacroType, StringRef Name,
 198                                 StringRef Value) {
 199   assert(!Name.empty() && "Unable to create macro without name");
 200   assert((MacroType == dwarf::DW_MACINFO_undef ||
 201           MacroType == dwarf::DW_MACINFO_define) &&
 202          "Unexpected macro type");
 203   auto *M = DIMacro::get(VMContext, MacroType, LineNumber, Name, Value);
 204   AllMacrosPerParent[Parent].insert(M);
 205   return M;
 206 }
 207
 208 DIMacroFile *DIBuilder::createTempMacroFile(DIMacroFile *Parent,
 209                                             unsigned LineNumber, DIFile *File) {
 210   auto *MF = DIMacroFile::getTemporary(VMContext, dwarf::DW_MACINFO_start_file,
 211                                        LineNumber, File, DIMacroNodeArray())
 212                  .release();
 213   AllMacrosPerParent[Parent].insert(MF);
 214   // Add the new temporary DIMacroFile to the macro per parent map as a parent.
 215   // This is needed to assure DIMacroFile with no children to have an entry in
 216   // the map. Otherwise, it will not be resolved in DIBuilder::finalize().
 217   AllMacrosPerParent.insert({MF, {}});
 218   return MF;
 219 }
 220
 221 DIEnumerator *DIBuilder::createEnumerator(StringRef Name, int64_t Val) {
 222   assert(!Name.empty() && "Unable to create enumerator without name");
 223   return DIEnumerator::get(VMContext, Val, Name);
 224 }
 225
 226 DIBasicType *DIBuilder::createUnspecifiedType(StringRef Name) {
 227   assert(!Name.empty() && "Unable to create type without name");
 228   return DIBasicType::get(VMContext, dwarf::DW_TAG_unspecified_type, Name);
 229 }
 230
 231 DIBasicType *DIBuilder::createNullPtrType() {
 232   return createUnspecifiedType("decltype(nullptr)");
 233 }
 234
 235 DIBasicType *DIBuilder::createBasicType(StringRef Name, uint64_t SizeInBits,
 236                                         unsigned Encoding) {
 237   assert(!Name.empty() && "Unable to create type without name");
 238   return DIBasicType::get(VMContext, dwarf::DW_TAG_base_type, Name, SizeInBits,
 239                           0, Encoding);
 240 }
 241
 242 DIDerivedType *DIBuilder::createQualifiedType(unsigned Tag, DIType *FromTy) {
 243   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr, FromTy, 0,
 244                             0, 0, None, DINode::FlagZero);
 245 }
 246
 247 DIDerivedType *DIBuilder::createPointerType(
 248     DIType *PointeeTy,
 249     uint64_t SizeInBits,
 250     uint32_t AlignInBits,
 251     Optional<unsigned> DWARFAddressSpace,
 252     StringRef Name) {
 253   // FIXME: Why is there a name here?
 254   return DIDerivedType::get(VMContext, dwarf::DW_TAG_pointer_type, Name,
 255                             nullptr, 0, nullptr, PointeeTy, SizeInBits,
 256                             AlignInBits, 0, DWARFAddressSpace,
 257                             DINode::FlagZero);
 258 }
 259
 260 DIDerivedType *DIBuilder::createMemberPointerType(DIType *PointeeTy,
 261                                                   DIType *Base,
 262                                                   uint64_t SizeInBits,
 263                                                   uint32_t AlignInBits,
 264                                                   DINode::DIFlags Flags) {
 265   return DIDerivedType::get(VMContext, dwarf::DW_TAG_ptr_to_member_type, "",
 266                             nullptr, 0, nullptr, PointeeTy, SizeInBits,
 267                             AlignInBits, 0, None, Flags, Base);
 268 }
 269
 270 DIDerivedType *DIBuilder::createReferenceType(
 271     unsigned Tag, DIType *RTy,
 272     uint64_t SizeInBits,
 273     uint32_t AlignInBits,
 274     Optional<unsigned> DWARFAddressSpace) {
 275   assert(RTy && "Unable to create reference type");
 276   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr, RTy,
 277                             SizeInBits, AlignInBits, 0, DWARFAddressSpace,
 278                             DINode::FlagZero);
 279 }
 280
 281 DIDerivedType *DIBuilder::createTypedef(DIType *Ty, StringRef Name,
 282                                         DIFile *File, unsigned LineNo,
 283                                         DIScope *Context) {
 284   return DIDerivedType::get(VMContext, dwarf::DW_TAG_typedef, Name, File,
 285                             LineNo, getNonCompileUnitScope(Context), Ty, 0, 0,
 286                             0, None, DINode::FlagZero);
 287 }
 288
 289 DIDerivedType *DIBuilder::createFriend(DIType *Ty, DIType *FriendTy) {
 290   assert(Ty && "Invalid type!");
 291   assert(FriendTy && "Invalid friend type!");
 292   return DIDerivedType::get(VMContext, dwarf::DW_TAG_friend, "", nullptr, 0, Ty,
 293                             FriendTy, 0, 0, 0, None, DINode::FlagZero);
 294 }
 295
 296 DIDerivedType *DIBuilder::createInheritance(DIType *Ty, DIType *BaseTy,
 297                                             uint64_t BaseOffset,
 298                                             DINode::DIFlags Flags) {
 299   assert(Ty && "Unable to create inheritance");
 300   return DIDerivedType::get(VMContext, dwarf::DW_TAG_inheritance, "", nullptr,
 301                             0, Ty, BaseTy, 0, 0, BaseOffset, None, Flags);
 302 }
 303
 304 DIDerivedType *DIBuilder::createMemberType(DIScope *Scope, StringRef Name,
 305                                            DIFile *File, unsigned LineNumber,
 306                                            uint64_t SizeInBits,
 307                                            uint32_t AlignInBits,
 308                                            uint64_t OffsetInBits,
 309                                            DINode::DIFlags Flags, DIType *Ty) {
 310   return DIDerivedType::get(VMContext, dwarf::DW_TAG_member, Name, File,
 311                             LineNumber, getNonCompileUnitScope(Scope), Ty,
 312                             SizeInBits, AlignInBits, OffsetInBits, None, Flags);
 313 }
 314
 315 static ConstantAsMetadata *getConstantOrNull(Constant *C) {
 316   if (C)
 317     return ConstantAsMetadata::get(C);
 318   return nullptr;
 319 }
 320
 321 DIDerivedType *DIBuilder::createBitFieldMemberType(
 322     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 323     uint64_t SizeInBits, uint64_t OffsetInBits, uint64_t StorageOffsetInBits,
 324     DINode::DIFlags Flags, DIType *Ty) {
 325   Flags |= DINode::FlagBitField;
 326   return DIDerivedType::get(
 327       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 328       getNonCompileUnitScope(Scope), Ty, SizeInBits, /* AlignInBits */ 0,
 329       OffsetInBits, None, Flags,
 330       ConstantAsMetadata::get(ConstantInt::get(IntegerType::get(VMContext, 64),
 331                                                StorageOffsetInBits)));
 332 }
 333
 334 DIDerivedType *
 335 DIBuilder::createStaticMemberType(DIScope *Scope, StringRef Name, DIFile *File,
 336                                   unsigned LineNumber, DIType *Ty,
 337                                   DINode::DIFlags Flags, llvm::Constant *Val,
 338                                   uint32_t AlignInBits) {
 339   Flags |= DINode::FlagStaticMember;
 340   return DIDerivedType::get(VMContext, dwarf::DW_TAG_member, Name, File,
 341                             LineNumber, getNonCompileUnitScope(Scope), Ty, 0,
 342                             AlignInBits, 0, None, Flags,
 343                             getConstantOrNull(Val));
 344 }
 345
 346 DIDerivedType *
 347 DIBuilder::createObjCIVar(StringRef Name, DIFile *File, unsigned LineNumber,
 348                           uint64_t SizeInBits, uint32_t AlignInBits,
 349                           uint64_t OffsetInBits, DINode::DIFlags Flags,
 350                           DIType *Ty, MDNode *PropertyNode) {
 351   return DIDerivedType::get(VMContext, dwarf::DW_TAG_member, Name, File,
 352                             LineNumber, getNonCompileUnitScope(File), Ty,
 353                             SizeInBits, AlignInBits, OffsetInBits, None, Flags,
 354                             PropertyNode);
 355 }
 356
 357 DIObjCProperty *
 358 DIBuilder::createObjCProperty(StringRef Name, DIFile *File, unsigned LineNumber,
 359                               StringRef GetterName, StringRef SetterName,
 360                               unsigned PropertyAttributes, DIType *Ty) {
 361   return DIObjCProperty::get(VMContext, Name, File, LineNumber, GetterName,
 362                              SetterName, PropertyAttributes, Ty);
 363 }
 364
 365 DITemplateTypeParameter *
 366 DIBuilder::createTemplateTypeParameter(DIScope *Context, StringRef Name,
 367                                        DIType *Ty) {
 368   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 369   return DITemplateTypeParameter::get(VMContext, Name, Ty);
 370 }
 371
 372 static DITemplateValueParameter *
 373 createTemplateValueParameterHelper(LLVMContext &VMContext, unsigned Tag,
 374                                    DIScope *Context, StringRef Name, DIType *Ty,
 375                                    Metadata *MD) {
 376   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 377   return DITemplateValueParameter::get(VMContext, Tag, Name, Ty, MD);
 378 }
 379
 380 DITemplateValueParameter *
 381 DIBuilder::createTemplateValueParameter(DIScope *Context, StringRef Name,
 382                                         DIType *Ty, Constant *Val) {
 383   return createTemplateValueParameterHelper(
 384       VMContext, dwarf::DW_TAG_template_value_parameter, Context, Name, Ty,
 385       getConstantOrNull(Val));
 386 }
 387
 388 DITemplateValueParameter *
 389 DIBuilder::createTemplateTemplateParameter(DIScope *Context, StringRef Name,
 390                                            DIType *Ty, StringRef Val) {
 391   return createTemplateValueParameterHelper(
 392       VMContext, dwarf::DW_TAG_GNU_template_template_param, Context, Name, Ty,
 393       MDString::get(VMContext, Val));
 394 }
 395
 396 DITemplateValueParameter *
 397 DIBuilder::createTemplateParameterPack(DIScope *Context, StringRef Name,
 398                                        DIType *Ty, DINodeArray Val) {
 399   return createTemplateValueParameterHelper(
 400       VMContext, dwarf::DW_TAG_GNU_template_parameter_pack, Context, Name, Ty,
 401       Val.get());
 402 }
 403
 404 DICompositeType *DIBuilder::createClassType(
 405     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 406     uint64_t SizeInBits, uint32_t AlignInBits, uint64_t OffsetInBits,
 407     DINode::DIFlags Flags, DIType *DerivedFrom, DINodeArray Elements,
 408     DIType *VTableHolder, MDNode *TemplateParams, StringRef UniqueIdentifier) {
 409   assert((!Context || isa<DIScope>(Context)) &&
 410          "createClassType should be called with a valid Context");
 411
 412   auto *R = DICompositeType::get(
 413       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 414       getNonCompileUnitScope(Context), DerivedFrom, SizeInBits, AlignInBits,
 415       OffsetInBits, Flags, Elements, 0, VTableHolder,
 416       cast_or_null<MDTuple>(TemplateParams), UniqueIdentifier);
 417   trackIfUnresolved(R);
 418   return R;
 419 }
 420
 421 DICompositeType *DIBuilder::createStructType(
 422     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 423     uint64_t SizeInBits, uint32_t AlignInBits, DINode::DIFlags Flags,
 424     DIType *DerivedFrom, DINodeArray Elements, unsigned RunTimeLang,
 425     DIType *VTableHolder, StringRef UniqueIdentifier) {
 426   auto *R = DICompositeType::get(
 427       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 428       getNonCompileUnitScope(Context), DerivedFrom, SizeInBits, AlignInBits, 0,
 429       Flags, Elements, RunTimeLang, VTableHolder, nullptr, UniqueIdentifier);
 430   trackIfUnresolved(R);
 431   return R;
 432 }
 433
 434 DICompositeType *DIBuilder::createUnionType(
 435     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 436     uint64_t SizeInBits, uint32_t AlignInBits, DINode::DIFlags Flags,
 437     DINodeArray Elements, unsigned RunTimeLang, StringRef UniqueIdentifier) {
 438   auto *R = DICompositeType::get(
 439       VMContext, dwarf::DW_TAG_union_type, Name, File, LineNumber,
 440       getNonCompileUnitScope(Scope), nullptr, SizeInBits, AlignInBits, 0, Flags,
 441       Elements, RunTimeLang, nullptr, nullptr, UniqueIdentifier);
 442   trackIfUnresolved(R);
 443   return R;
 444 }
 445
 446 DISubroutineType *DIBuilder::createSubroutineType(DITypeRefArray ParameterTypes,
 447                                                   DINode::DIFlags Flags,
 448                                                   unsigned CC) {
 449   return DISubroutineType::get(VMContext, Flags, CC, ParameterTypes);
 450 }
 451
 452 DICompositeType *DIBuilder::createEnumerationType(
 453     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 454     uint64_t SizeInBits, uint32_t AlignInBits, DINodeArray Elements,
 455     DIType *UnderlyingType, StringRef UniqueIdentifier) {
 456   auto *CTy = DICompositeType::get(
 457       VMContext, dwarf::DW_TAG_enumeration_type, Name, File, LineNumber,
 458       getNonCompileUnitScope(Scope), UnderlyingType, SizeInBits, AlignInBits, 0,
 459       DINode::FlagZero, Elements, 0, nullptr, nullptr, UniqueIdentifier);
 460   AllEnumTypes.push_back(CTy);
 461   trackIfUnresolved(CTy);
 462   return CTy;
 463 }
 464
 465 DICompositeType *DIBuilder::createArrayType(uint64_t Size,
 466                                             uint32_t AlignInBits, DIType *Ty,
 467                                             DINodeArray Subscripts) {
 468   auto *R = DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "",
 469                                  nullptr, 0, nullptr, Ty, Size, AlignInBits, 0,
 470                                  DINode::FlagZero, Subscripts, 0, nullptr);
 471   trackIfUnresolved(R);
 472   return R;
 473 }
 474
 475 DICompositeType *DIBuilder::createVectorType(uint64_t Size,
 476                                              uint32_t AlignInBits, DIType *Ty,
 477                                              DINodeArray Subscripts) {
 478   auto *R = DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "",
 479                                  nullptr, 0, nullptr, Ty, Size, AlignInBits, 0,
 480                                  DINode::FlagVector, Subscripts, 0, nullptr);
 481   trackIfUnresolved(R);
 482   return R;
 483 }
 484
 485 static DIType *createTypeWithFlags(LLVMContext &Context, DIType *Ty,
 486                                    DINode::DIFlags FlagsToSet) {
 487   auto NewTy = Ty->clone();
 488   NewTy->setFlags(NewTy->getFlags() | FlagsToSet);
 489   return MDNode::replaceWithUniqued(std::move(NewTy));
 490 }
 491
 492 DIType *DIBuilder::createArtificialType(DIType *Ty) {
 493   // FIXME: Restrict this to the nodes where it's valid.
 494   if (Ty->isArtificial())
 495     return Ty;
 496   return createTypeWithFlags(VMContext, Ty, DINode::FlagArtificial);
 497 }
 498
 499 DIType *DIBuilder::createObjectPointerType(DIType *Ty) {
 500   // FIXME: Restrict this to the nodes where it's valid.
 501   if (Ty->isObjectPointer())
 502     return Ty;
 503   DINode::DIFlags Flags = DINode::FlagObjectPointer | DINode::FlagArtificial;
 504   return createTypeWithFlags(VMContext, Ty, Flags);
 505 }
 506
 507 void DIBuilder::retainType(DIScope *T) {
 508   assert(T && "Expected non-null type");
 509   assert((isa<DIType>(T) || (isa<DISubprogram>(T) &&
 510                              cast<DISubprogram>(T)->isDefinition() == false)) &&
 511          "Expected type or subprogram declaration");
 512   AllRetainTypes.emplace_back(T);
 513 }
 514
 515 DIBasicType *DIBuilder::createUnspecifiedParameter() { return nullptr; }
 516
 517 DICompositeType *
 518 DIBuilder::createForwardDecl(unsigned Tag, StringRef Name, DIScope *Scope,
 519                              DIFile *F, unsigned Line, unsigned RuntimeLang,
 520                              uint64_t SizeInBits, uint32_t AlignInBits,
 521                              StringRef UniqueIdentifier) {
 522   // FIXME: Define in terms of createReplaceableForwardDecl() by calling
 523   // replaceWithUniqued().
 524   auto *RetTy = DICompositeType::get(
 525       VMContext, Tag, Name, F, Line, getNonCompileUnitScope(Scope), nullptr,
 526       SizeInBits, AlignInBits, 0, DINode::FlagFwdDecl, nullptr, RuntimeLang,
 527       nullptr, nullptr, UniqueIdentifier);
 528   trackIfUnresolved(RetTy);
 529   return RetTy;
 530 }
 531
 532 DICompositeType *DIBuilder::createReplaceableCompositeType(
 533     unsigned Tag, StringRef Name, DIScope *Scope, DIFile *F, unsigned Line,
 534     unsigned RuntimeLang, uint64_t SizeInBits, uint32_t AlignInBits,
 535     DINode::DIFlags Flags, StringRef UniqueIdentifier) {
 536   auto *RetTy =
 537       DICompositeType::getTemporary(
 538           VMContext, Tag, Name, F, Line, getNonCompileUnitScope(Scope), nullptr,
 539           SizeInBits, AlignInBits, 0, Flags, nullptr, RuntimeLang, nullptr,
 540           nullptr, UniqueIdentifier)
 541           .release();
 542   trackIfUnresolved(RetTy);
 543   return RetTy;
 544 }
 545
 546 DINodeArray DIBuilder::getOrCreateArray(ArrayRef<Metadata *> Elements) {
 547   return MDTuple::get(VMContext, Elements);
 548 }
 549
 550 DIMacroNodeArray
 551 DIBuilder::getOrCreateMacroArray(ArrayRef<Metadata *> Elements) {
 552   return MDTuple::get(VMContext, Elements);
 553 }
 554
 555 DITypeRefArray DIBuilder::getOrCreateTypeArray(ArrayRef<Metadata *> Elements) {
 556   SmallVector<llvm::Metadata *, 16> Elts;
 557   for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
 558     if (Elements[i] && isa<MDNode>(Elements[i]))
 559       Elts.push_back(cast<DIType>(Elements[i]));
 560     else
 561       Elts.push_back(Elements[i]);
 562   }
 563   return DITypeRefArray(MDNode::get(VMContext, Elts));
 564 }
 565
 566 DISubrange *DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Count) {
 567   return DISubrange::get(VMContext, Count, Lo);
 568 }
 569
 570 static void checkGlobalVariableScope(DIScope *Context) {
 571 #ifndef NDEBUG
 572   if (auto *CT =
 573           dyn_cast_or_null<DICompositeType>(getNonCompileUnitScope(Context)))
 574     assert(CT->getIdentifier().empty() &&
 575            "Context of a global variable should not be a type with identifier");
 576 #endif
 577 }
 578
 579 DIGlobalVariableExpression *DIBuilder::createGlobalVariableExpression(
 580     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 581     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, DIExpression *Expr,
 582     MDNode *Decl, uint32_t AlignInBits) {
 583   checkGlobalVariableScope(Context);
 584
 585   auto *GV = DIGlobalVariable::getDistinct(
 586       VMContext, cast_or_null<DIScope>(Context), Name, LinkageName, F,
 587       LineNumber, Ty, isLocalToUnit, true, cast_or_null<DIDerivedType>(Decl),
 588       AlignInBits);
 589   auto *N = DIGlobalVariableExpression::get(VMContext, GV, Expr);
 590   AllGVs.push_back(N);
 591   return N;
 592 }
 593
 594 DIGlobalVariable *DIBuilder::createTempGlobalVariableFwdDecl(
 595     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 596     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, MDNode *Decl,
 597     uint32_t AlignInBits) {
 598   checkGlobalVariableScope(Context);
 599
 600   return DIGlobalVariable::getTemporary(
 601              VMContext, cast_or_null<DIScope>(Context), Name, LinkageName, F,
 602              LineNumber, Ty, isLocalToUnit, false,
 603              cast_or_null<DIDerivedType>(Decl), AlignInBits)
 604       .release();
 605 }
 606
 607 static DILocalVariable *createLocalVariable(
 608     LLVMContext &VMContext,
 609     DenseMap<MDNode *, SmallVector<TrackingMDNodeRef, 1>> &PreservedVariables,
 610     DIScope *Scope, StringRef Name, unsigned ArgNo, DIFile *File,
 611     unsigned LineNo, DIType *Ty, bool AlwaysPreserve, DINode::DIFlags Flags,
 612     uint32_t AlignInBits) {
 613   // FIXME: Why getNonCompileUnitScope()?
 614   // FIXME: Why is "!Context" okay here?
 615   // FIXME: Why doesn't this check for a subprogram or lexical block (AFAICT
 616   // the only valid scopes)?
 617   DIScope *Context = getNonCompileUnitScope(Scope);
 618
 619   auto *Node =
 620       DILocalVariable::get(VMContext, cast_or_null<DILocalScope>(Context), Name,
 621                            File, LineNo, Ty, ArgNo, Flags, AlignInBits);
 622   if (AlwaysPreserve) {
 623     // The optimizer may remove local variables. If there is an interest
 624     // to preserve variable info in such situation then stash it in a
 625     // named mdnode.
 626     DISubprogram *Fn = getDISubprogram(Scope);
 627     assert(Fn && "Missing subprogram for local variable");
 628     PreservedVariables[Fn].emplace_back(Node);
 629   }
 630   return Node;
 631 }
 632
 633 DILocalVariable *DIBuilder::createAutoVariable(DIScope *Scope, StringRef Name,
 634                                                DIFile *File, unsigned LineNo,
 635                                                DIType *Ty, bool AlwaysPreserve,
 636                                                DINode::DIFlags Flags,
 637                                                uint32_t AlignInBits) {
 638   return createLocalVariable(VMContext, PreservedVariables, Scope, Name,
 639                              /* ArgNo */ 0, File, LineNo, Ty, AlwaysPreserve,
 640                              Flags, AlignInBits);
 641 }
 642
 643 DILocalVariable *DIBuilder::createParameterVariable(
 644     DIScope *Scope, StringRef Name, unsigned ArgNo, DIFile *File,
 645     unsigned LineNo, DIType *Ty, bool AlwaysPreserve, DINode::DIFlags Flags) {
 646   assert(ArgNo && "Expected non-zero argument number for parameter");
 647   return createLocalVariable(VMContext, PreservedVariables, Scope, Name, ArgNo,
 648                              File, LineNo, Ty, AlwaysPreserve, Flags,
 649                              /* AlignInBits */0);
 650 }
 651
 652 DIExpression *DIBuilder::createExpression(ArrayRef<uint64_t> Addr) {
 653   return DIExpression::get(VMContext, Addr);
 654 }
 655
 656 DIExpression *DIBuilder::createExpression(ArrayRef<int64_t> Signed) {
 657   // TODO: Remove the callers of this signed version and delete.
 658   SmallVector<uint64_t, 8> Addr(Signed.begin(), Signed.end());
 659   return createExpression(Addr);
 660 }
 661
 662 DIExpression *DIBuilder::createFragmentExpression(unsigned OffsetInBytes,
 663                                                   unsigned SizeInBytes) {
 664   uint64_t Addr[] = {dwarf::DW_OP_LLVM_fragment, OffsetInBytes, SizeInBytes};
 665   return DIExpression::get(VMContext, Addr);
 666 }
 667
 668 template <class... Ts>
 669 static DISubprogram *getSubprogram(bool IsDistinct, Ts &&... Args) {
 670   if (IsDistinct)
 671     return DISubprogram::getDistinct(std::forward<Ts>(Args)...);
 672   return DISubprogram::get(std::forward<Ts>(Args)...);
 673 }
 674
 675 DISubprogram *DIBuilder::createFunction(
 676     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *File,
 677     unsigned LineNo, DISubroutineType *Ty, bool isLocalToUnit,
 678     bool isDefinition, unsigned ScopeLine, DINode::DIFlags Flags,
 679     bool isOptimized, DITemplateParameterArray TParams, DISubprogram *Decl,
 680     DITypeArray ThrownTypes) {
 681   auto *Node = getSubprogram(
 682       /* IsDistinct = */ isDefinition, VMContext,
 683       getNonCompileUnitScope(Context), Name, LinkageName, File, LineNo, Ty,
 684       isLocalToUnit, isDefinition, ScopeLine, nullptr, 0, 0, 0, Flags,
 685       isOptimized, isDefinition ? CUNode : nullptr, TParams, Decl,
 686       MDTuple::getTemporary(VMContext, None).release(), ThrownTypes);
 687
 688   if (isDefinition)
 689     AllSubprograms.push_back(Node);
 690   trackIfUnresolved(Node);
 691   return Node;
 692 }
 693
 694 DISubprogram *DIBuilder::createTempFunctionFwdDecl(
 695     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *File,
 696     unsigned LineNo, DISubroutineType *Ty, bool isLocalToUnit,
 697     bool isDefinition, unsigned ScopeLine, DINode::DIFlags Flags,
 698     bool isOptimized, DITemplateParameterArray TParams, DISubprogram *Decl,
 699     DITypeArray ThrownTypes) {
 700   return DISubprogram::getTemporary(
 701              VMContext, getNonCompileUnitScope(Context), Name, LinkageName,
 702              File, LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine, nullptr,
 703              0, 0, 0, Flags, isOptimized, isDefinition ? CUNode : nullptr,
 704              TParams, Decl, nullptr, ThrownTypes)
 705       .release();
 706 }
 707
 708 DISubprogram *DIBuilder::createMethod(
 709     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 710     unsigned LineNo, DISubroutineType *Ty, bool isLocalToUnit,
 711     bool isDefinition, unsigned VK, unsigned VIndex, int ThisAdjustment,
 712     DIType *VTableHolder, DINode::DIFlags Flags, bool isOptimized,
 713     DITemplateParameterArray TParams, DITypeArray ThrownTypes) {
 714   assert(getNonCompileUnitScope(Context) &&
 715          "Methods should have both a Context and a context that isn't "
 716          "the compile unit.");
 717   // FIXME: Do we want to use different scope/lines?
 718   auto *SP = getSubprogram(
 719       /* IsDistinct = */ isDefinition, VMContext, cast<DIScope>(Context), Name,
 720       LinkageName, F, LineNo, Ty, isLocalToUnit, isDefinition, LineNo,
 721       VTableHolder, VK, VIndex, ThisAdjustment, Flags, isOptimized,
 722       isDefinition ? CUNode : nullptr, TParams, nullptr, nullptr, ThrownTypes);
 723
 724   if (isDefinition)
 725     AllSubprograms.push_back(SP);
 726   trackIfUnresolved(SP);
 727   return SP;
 728 }
 729
 730 DINamespace *DIBuilder::createNameSpace(DIScope *Scope, StringRef Name,
 731                                         bool ExportSymbols) {
 732
 733   // It is okay to *not* make anonymous top-level namespaces distinct, because
 734   // all nodes that have an anonymous namespace as their parent scope are
 735   // guaranteed to be unique and/or are linked to their containing
 736   // DICompileUnit. This decision is an explicit tradeoff of link time versus
 737   // memory usage versus code simplicity and may get revisited in the future.
 738   return DINamespace::get(VMContext, getNonCompileUnitScope(Scope), Name,
 739                           ExportSymbols);
 740 }
 741
 742 DIModule *DIBuilder::createModule(DIScope *Scope, StringRef Name,
 743                                   StringRef ConfigurationMacros,
 744                                   StringRef IncludePath,
 745                                   StringRef ISysRoot) {
 746  return DIModule::get(VMContext, getNonCompileUnitScope(Scope), Name,
 747                       ConfigurationMacros, IncludePath, ISysRoot);
 748 }
 749
 750 DILexicalBlockFile *DIBuilder::createLexicalBlockFile(DIScope *Scope,
 751                                                       DIFile *File,
 752                                                       unsigned Discriminator) {
 753   return DILexicalBlockFile::get(VMContext, Scope, File, Discriminator);
 754 }
 755
 756 DILexicalBlock *DIBuilder::createLexicalBlock(DIScope *Scope, DIFile *File,
 757                                               unsigned Line, unsigned Col) {
 758   // Make these distinct, to avoid merging two lexical blocks on the same
 759   // file/line/column.
 760   return DILexicalBlock::getDistinct(VMContext, getNonCompileUnitScope(Scope),
 761                                      File, Line, Col);
 762 }
 763
 764 static Value *getDbgIntrinsicValueImpl(LLVMContext &VMContext, Value *V) {
 765   assert(V && "no value passed to dbg intrinsic");
 766   return MetadataAsValue::get(VMContext, ValueAsMetadata::get(V));
 767 }
 768
 769 static Instruction *withDebugLoc(Instruction *I, const DILocation *DL) {
 770   I->setDebugLoc(const_cast<DILocation *>(DL));
 771   return I;
 772 }
 773
 774 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 775                                       DIExpression *Expr, const DILocation *DL,
 776                                       Instruction *InsertBefore) {
 777   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
 778   assert(DL && "Expected debug loc");
 779   assert(DL->getScope()->getSubprogram() ==
 780              VarInfo->getScope()->getSubprogram() &&
 781          "Expected matching subprograms");
 782   if (!DeclareFn)
 783     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 784
 785   trackIfUnresolved(VarInfo);
 786   trackIfUnresolved(Expr);
 787   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
 788                    MetadataAsValue::get(VMContext, VarInfo),
 789                    MetadataAsValue::get(VMContext, Expr)};
 790   return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertBefore), DL);
 791 }
 792
 793 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 794                                       DIExpression *Expr, const DILocation *DL,
 795                                       BasicBlock *InsertAtEnd) {
 796   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
 797   assert(DL && "Expected debug loc");
 798   assert(DL->getScope()->getSubprogram() ==
 799              VarInfo->getScope()->getSubprogram() &&
 800          "Expected matching subprograms");
 801   if (!DeclareFn)
 802     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 803
 804   trackIfUnresolved(VarInfo);
 805   trackIfUnresolved(Expr);
 806   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
 807                    MetadataAsValue::get(VMContext, VarInfo),
 808                    MetadataAsValue::get(VMContext, Expr)};
 809
 810   // If this block already has a terminator then insert this intrinsic
 811   // before the terminator.
 812   if (TerminatorInst *T = InsertAtEnd->getTerminator())
 813     return withDebugLoc(CallInst::Create(DeclareFn, Args, "", T), DL);
 814   return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertAtEnd), DL);
 815 }
 816
 817 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
 818                                                 DILocalVariable *VarInfo,
 819                                                 DIExpression *Expr,
 820                                                 const DILocation *DL,
 821                                                 Instruction *InsertBefore) {
 822   assert(V && "no value passed to dbg.value");
 823   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
 824   assert(DL && "Expected debug loc");
 825   assert(DL->getScope()->getSubprogram() ==
 826              VarInfo->getScope()->getSubprogram() &&
 827          "Expected matching subprograms");
 828   if (!ValueFn)
 829     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
 830
 831   trackIfUnresolved(VarInfo);
 832   trackIfUnresolved(Expr);
 833   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
 834                    ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
 835                    MetadataAsValue::get(VMContext, VarInfo),
 836                    MetadataAsValue::get(VMContext, Expr)};
 837   return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertBefore), DL);
 838 }
 839
 840 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
 841                                                 DILocalVariable *VarInfo,
 842                                                 DIExpression *Expr,
 843                                                 const DILocation *DL,
 844                                                 BasicBlock *InsertAtEnd) {
 845   assert(V && "no value passed to dbg.value");
 846   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
 847   assert(DL && "Expected debug loc");
 848   assert(DL->getScope()->getSubprogram() ==
 849              VarInfo->getScope()->getSubprogram() &&
 850          "Expected matching subprograms");
 851   if (!ValueFn)
 852     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
 853
 854   trackIfUnresolved(VarInfo);
 855   trackIfUnresolved(Expr);
 856   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
 857                    ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
 858                    MetadataAsValue::get(VMContext, VarInfo),
 859                    MetadataAsValue::get(VMContext, Expr)};
 860
 861   return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertAtEnd), DL);
 862 }
 863
 864 void DIBuilder::replaceVTableHolder(DICompositeType *&T,
 865                                     DICompositeType *VTableHolder) {
 866   {
 867     TypedTrackingMDRef<DICompositeType> N(T);
 868     N->replaceVTableHolder(VTableHolder);
 869     T = N.get();
 870   }
 871
 872   // If this didn't create a self-reference, just return.
 873   if (T != VTableHolder)
 874     return;
 875
 876   // Look for unresolved operands.  T will drop RAUW support, orphaning any
 877   // cycles underneath it.
 878   if (T->isResolved())
 879     for (const MDOperand &O : T->operands())
 880       if (auto *N = dyn_cast_or_null<MDNode>(O))
 881         trackIfUnresolved(N);
 882 }
 883
 884 void DIBuilder::replaceArrays(DICompositeType *&T, DINodeArray Elements,
 885                               DINodeArray TParams) {
 886   {
 887     TypedTrackingMDRef<DICompositeType> N(T);
 888     if (Elements)
 889       N->replaceElements(Elements);
 890     if (TParams)
 891       N->replaceTemplateParams(DITemplateParameterArray(TParams));
 892     T = N.get();
 893   }
 894
 895   // If T isn't resolved, there's no problem.
 896   if (!T->isResolved())
 897     return;
 898
 899   // If T is resolved, it may be due to a self-reference cycle.  Track the
 900   // arrays explicitly if they're unresolved, or else the cycles will be
 901   // orphaned.
 902   if (Elements)
 903     trackIfUnresolved(Elements.get());
 904   if (TParams)
 905     trackIfUnresolved(TParams.get());
 906 }