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