lib/IR/DIBuilder.cpp

   1 //===--- DIBuilder.cpp - Debug Information Builder ------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the DIBuilder.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/IR/DIBuilder.h"
  15 #include "llvm/ADT/STLExtras.h"
  16 #include "llvm/IR/Constants.h"
  17 #include "llvm/IR/DebugInfo.h"
  18 #include "llvm/IR/IntrinsicInst.h"
  19 #include "llvm/IR/Module.h"
  20 #include "llvm/Support/Debug.h"
  21 #include "llvm/Support/Dwarf.h"
  22
  23 using namespace llvm;
  24 using namespace llvm::dwarf;
  25
  26 namespace {
  27 class HeaderBuilder {
  28   /// \brief Whether there are any fields yet.
  29   ///
  30   /// Note that this is not equivalent to \c Chars.empty(), since \a concat()
  31   /// may have been called already with an empty string.
  32   bool IsEmpty;
  33   SmallVector<char, 256> Chars;
  34
  35 public:
  36   HeaderBuilder() : IsEmpty(true) {}
  37   HeaderBuilder(const HeaderBuilder &X) : IsEmpty(X.IsEmpty), Chars(X.Chars) {}
  38   HeaderBuilder(HeaderBuilder &&X)
  39       : IsEmpty(X.IsEmpty), Chars(std::move(X.Chars)) {}
  40
  41   template <class Twineable> HeaderBuilder &concat(Twineable &&X) {
  42     if (IsEmpty)
  43       IsEmpty = false;
  44     else
  45       Chars.push_back(0);
  46     Twine(X).toVector(Chars);
  47     return *this;
  48   }
  49
  50   MDString *get(LLVMContext &Context) const {
  51     return MDString::get(Context, StringRef(Chars.begin(), Chars.size()));
  52   }
  53
  54   static HeaderBuilder get(unsigned Tag) {
  55     return HeaderBuilder().concat("0x" + Twine::utohexstr(Tag));
  56   }
  57 };
  58 }
  59
  60 DIBuilder::DIBuilder(Module &m, bool AllowUnresolvedNodes)
  61   : M(m), VMContext(M.getContext()), CUNode(nullptr),
  62       DeclareFn(nullptr), ValueFn(nullptr),
  63       AllowUnresolvedNodes(AllowUnresolvedNodes) {}
  64
  65 void DIBuilder::trackIfUnresolved(MDNode *N) {
  66   if (!N)
  67     return;
  68   if (N->isResolved())
  69     return;
  70
  71   assert(AllowUnresolvedNodes && "Cannot handle unresolved nodes");
  72   UnresolvedNodes.emplace_back(N);
  73 }
  74
  75 void DIBuilder::finalize() {
  76   if (!CUNode) {
  77     assert(!AllowUnresolvedNodes &&
  78            "creating type nodes without a CU is not supported");
  79     return;
  80   }
  81
  82   CUNode->replaceEnumTypes(MDTuple::get(VMContext, AllEnumTypes));
  83
  84   SmallVector<Metadata *, 16> RetainValues;
  85   // Declarations and definitions of the same type may be retained. Some
  86   // clients RAUW these pairs, leaving duplicates in the retained types
  87   // list. Use a set to remove the duplicates while we transform the
  88   // TrackingVHs back into Values.
  89   SmallPtrSet<Metadata *, 16> RetainSet;
  90   for (unsigned I = 0, E = AllRetainTypes.size(); I < E; I++)
  91     if (RetainSet.insert(AllRetainTypes[I]).second)
  92       RetainValues.push_back(AllRetainTypes[I]);
  93   CUNode->replaceRetainedTypes(MDTuple::get(VMContext, RetainValues));
  94
  95   DISubprogramArray SPs = MDTuple::get(VMContext, AllSubprograms);
  96   CUNode->replaceSubprograms(SPs.get());
  97   for (auto *SP : SPs) {
  98     if (MDTuple *Temp = SP->getVariables().get()) {
  99       const auto &PV = PreservedVariables.lookup(SP);
 100       SmallVector<Metadata *, 4> Variables(PV.begin(), PV.end());
 101       DINodeArray AV = getOrCreateArray(Variables);
 102       TempMDTuple(Temp)->replaceAllUsesWith(AV.get());
 103     }
 104   }
 105
 106   CUNode->replaceGlobalVariables(MDTuple::get(VMContext, AllGVs));
 107
 108   CUNode->replaceImportedEntities(MDTuple::get(
 109       VMContext, SmallVector<Metadata *, 16>(AllImportedModules.begin(),
 110                                              AllImportedModules.end())));
 111
 112   // Now that all temp nodes have been replaced or deleted, resolve remaining
 113   // cycles.
 114   for (const auto &N : UnresolvedNodes)
 115     if (N && !N->isResolved())
 116       N->resolveCycles();
 117   UnresolvedNodes.clear();
 118
 119   // Can't handle unresolved nodes anymore.
 120   AllowUnresolvedNodes = false;
 121 }
 122
 123 /// If N is compile unit return NULL otherwise return N.
 124 static DIScope *getNonCompileUnitScope(DIScope *N) {
 125   if (!N || isa<DICompileUnit>(N))
 126     return nullptr;
 127   return cast<DIScope>(N);
 128 }
 129
 130 DICompileUnit *DIBuilder::createCompileUnit(
 131     unsigned Lang, StringRef Filename, StringRef Directory, StringRef Producer,
 132     bool isOptimized, StringRef Flags, unsigned RunTimeVer, StringRef SplitName,
 133     DebugEmissionKind Kind, uint64_t DWOId, bool EmitDebugInfo) {
 134
 135   assert(((Lang <= dwarf::DW_LANG_Fortran08 && Lang >= dwarf::DW_LANG_C89) ||
 136           (Lang <= dwarf::DW_LANG_hi_user && Lang >= dwarf::DW_LANG_lo_user)) &&
 137          "Invalid Language tag");
 138   assert(!Filename.empty() &&
 139          "Unable to create compile unit without filename");
 140
 141   assert(!CUNode && "Can only make one compile unit per DIBuilder instance");
 142   CUNode = DICompileUnit::getDistinct(
 143       VMContext, Lang, DIFile::get(VMContext, Filename, Directory), Producer,
 144       isOptimized, Flags, RunTimeVer, SplitName, Kind, nullptr,
 145       nullptr, nullptr, nullptr, nullptr, DWOId);
 146
 147   // Create a named metadata so that it is easier to find cu in a module.
 148   // Note that we only generate this when the caller wants to actually
 149   // emit debug information. When we are only interested in tracking
 150   // source line locations throughout the backend, we prevent codegen from
 151   // emitting debug info in the final output by not generating llvm.dbg.cu.
 152   if (EmitDebugInfo) {
 153     NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.cu");
 154     NMD->addOperand(CUNode);
 155   }
 156
 157   trackIfUnresolved(CUNode);
 158   return CUNode;
 159 }
 160
 161 static DIImportedEntity *
 162 createImportedModule(LLVMContext &C, dwarf::Tag Tag, DIScope *Context,
 163                      Metadata *NS, unsigned Line, StringRef Name,
 164                      SmallVectorImpl<TrackingMDNodeRef> &AllImportedModules) {
 165   auto *M = DIImportedEntity::get(C, Tag, Context, DINodeRef(NS), Line, Name);
 166   AllImportedModules.emplace_back(M);
 167   return M;
 168 }
 169
 170 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 171                                                   DINamespace *NS,
 172                                                   unsigned Line) {
 173   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 174                                 Context, NS, Line, StringRef(), AllImportedModules);
 175 }
 176
 177 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
 178                                                   DIImportedEntity *NS,
 179                                                   unsigned Line) {
 180   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 181                                 Context, NS, Line, StringRef(), AllImportedModules);
 182 }
 183
 184 DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context, DIModule *M,
 185                                                   unsigned Line) {
 186   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
 187                                 Context, M, Line, StringRef(), AllImportedModules);
 188 }
 189
 190 DIImportedEntity *DIBuilder::createImportedDeclaration(DIScope *Context,
 191                                                        DINode *Decl,
 192                                                        unsigned Line,
 193                                                        StringRef Name) {
 194   // Make sure to use the unique identifier based metadata reference for
 195   // types that have one.
 196   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_declaration,
 197                                 Context, DINodeRef::get(Decl), Line, Name,
 198                                 AllImportedModules);
 199 }
 200
 201 DIFile *DIBuilder::createFile(StringRef Filename, StringRef Directory) {
 202   return DIFile::get(VMContext, Filename, Directory);
 203 }
 204
 205 DIEnumerator *DIBuilder::createEnumerator(StringRef Name, int64_t Val) {
 206   assert(!Name.empty() && "Unable to create enumerator without name");
 207   return DIEnumerator::get(VMContext, Val, Name);
 208 }
 209
 210 DIBasicType *DIBuilder::createUnspecifiedType(StringRef Name) {
 211   assert(!Name.empty() && "Unable to create type without name");
 212   return DIBasicType::get(VMContext, dwarf::DW_TAG_unspecified_type, Name);
 213 }
 214
 215 DIBasicType *DIBuilder::createNullPtrType() {
 216   return createUnspecifiedType("decltype(nullptr)");
 217 }
 218
 219 DIBasicType *DIBuilder::createBasicType(StringRef Name, uint64_t SizeInBits,
 220                                         uint64_t AlignInBits,
 221                                         unsigned Encoding) {
 222   assert(!Name.empty() && "Unable to create type without name");
 223   return DIBasicType::get(VMContext, dwarf::DW_TAG_base_type, Name, SizeInBits,
 224                           AlignInBits, Encoding);
 225 }
 226
 227 DIDerivedType *DIBuilder::createQualifiedType(unsigned Tag, DIType *FromTy) {
 228   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr,
 229                             DITypeRef::get(FromTy), 0, 0, 0, 0);
 230 }
 231
 232 DIDerivedType *DIBuilder::createPointerType(DIType *PointeeTy,
 233                                             uint64_t SizeInBits,
 234                                             uint64_t AlignInBits,
 235                                             StringRef Name) {
 236   // FIXME: Why is there a name here?
 237   return DIDerivedType::get(VMContext, dwarf::DW_TAG_pointer_type, Name,
 238                             nullptr, 0, nullptr, DITypeRef::get(PointeeTy),
 239                             SizeInBits, AlignInBits, 0, 0);
 240 }
 241
 242 DIDerivedType *DIBuilder::createMemberPointerType(DIType *PointeeTy,
 243                                                   DIType *Base,
 244                                                   uint64_t SizeInBits,
 245                                                   uint64_t AlignInBits) {
 246   return DIDerivedType::get(VMContext, dwarf::DW_TAG_ptr_to_member_type, "",
 247                             nullptr, 0, nullptr, DITypeRef::get(PointeeTy),
 248                             SizeInBits, AlignInBits, 0, 0,
 249                             DITypeRef::get(Base));
 250 }
 251
 252 DIDerivedType *DIBuilder::createReferenceType(unsigned Tag, DIType *RTy) {
 253   assert(RTy && "Unable to create reference type");
 254   return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr,
 255                             DITypeRef::get(RTy), 0, 0, 0, 0);
 256 }
 257
 258 DIDerivedType *DIBuilder::createTypedef(DIType *Ty, StringRef Name,
 259                                         DIFile *File, unsigned LineNo,
 260                                         DIScope *Context) {
 261   return DIDerivedType::get(VMContext, dwarf::DW_TAG_typedef, Name, File,
 262                             LineNo,
 263                             DIScopeRef::get(getNonCompileUnitScope(Context)),
 264                             DITypeRef::get(Ty), 0, 0, 0, 0);
 265 }
 266
 267 DIDerivedType *DIBuilder::createFriend(DIType *Ty, DIType *FriendTy) {
 268   assert(Ty && "Invalid type!");
 269   assert(FriendTy && "Invalid friend type!");
 270   return DIDerivedType::get(VMContext, dwarf::DW_TAG_friend, "", nullptr, 0,
 271                             DITypeRef::get(Ty), DITypeRef::get(FriendTy), 0, 0,
 272                             0, 0);
 273 }
 274
 275 DIDerivedType *DIBuilder::createInheritance(DIType *Ty, DIType *BaseTy,
 276                                             uint64_t BaseOffset,
 277                                             unsigned Flags) {
 278   assert(Ty && "Unable to create inheritance");
 279   return DIDerivedType::get(VMContext, dwarf::DW_TAG_inheritance, "", nullptr,
 280                             0, DITypeRef::get(Ty), DITypeRef::get(BaseTy), 0, 0,
 281                             BaseOffset, Flags);
 282 }
 283
 284 DIDerivedType *DIBuilder::createMemberType(DIScope *Scope, StringRef Name,
 285                                            DIFile *File, unsigned LineNumber,
 286                                            uint64_t SizeInBits,
 287                                            uint64_t AlignInBits,
 288                                            uint64_t OffsetInBits,
 289                                            unsigned Flags, DIType *Ty) {
 290   return DIDerivedType::get(
 291       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 292       DIScopeRef::get(getNonCompileUnitScope(Scope)), DITypeRef::get(Ty),
 293       SizeInBits, AlignInBits, OffsetInBits, Flags);
 294 }
 295
 296 static ConstantAsMetadata *getConstantOrNull(Constant *C) {
 297   if (C)
 298     return ConstantAsMetadata::get(C);
 299   return nullptr;
 300 }
 301
 302 DIDerivedType *DIBuilder::createStaticMemberType(DIScope *Scope, StringRef Name,
 303                                                  DIFile *File,
 304                                                  unsigned LineNumber,
 305                                                  DIType *Ty, unsigned Flags,
 306                                                  llvm::Constant *Val) {
 307   Flags |= DINode::FlagStaticMember;
 308   return DIDerivedType::get(
 309       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 310       DIScopeRef::get(getNonCompileUnitScope(Scope)), DITypeRef::get(Ty), 0, 0,
 311       0, Flags, getConstantOrNull(Val));
 312 }
 313
 314 DIDerivedType *DIBuilder::createObjCIVar(StringRef Name, DIFile *File,
 315                                          unsigned LineNumber,
 316                                          uint64_t SizeInBits,
 317                                          uint64_t AlignInBits,
 318                                          uint64_t OffsetInBits, unsigned Flags,
 319                                          DIType *Ty, MDNode *PropertyNode) {
 320   return DIDerivedType::get(
 321       VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
 322       DIScopeRef::get(getNonCompileUnitScope(File)), DITypeRef::get(Ty),
 323       SizeInBits, AlignInBits, OffsetInBits, Flags, PropertyNode);
 324 }
 325
 326 DIObjCProperty *
 327 DIBuilder::createObjCProperty(StringRef Name, DIFile *File, unsigned LineNumber,
 328                               StringRef GetterName, StringRef SetterName,
 329                               unsigned PropertyAttributes, DIType *Ty) {
 330   return DIObjCProperty::get(VMContext, Name, File, LineNumber, GetterName,
 331                              SetterName, PropertyAttributes,
 332                              DITypeRef::get(Ty));
 333 }
 334
 335 DITemplateTypeParameter *
 336 DIBuilder::createTemplateTypeParameter(DIScope *Context, StringRef Name,
 337                                        DIType *Ty) {
 338   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 339   return DITemplateTypeParameter::get(VMContext, Name, DITypeRef::get(Ty));
 340 }
 341
 342 static DITemplateValueParameter *
 343 createTemplateValueParameterHelper(LLVMContext &VMContext, unsigned Tag,
 344                                    DIScope *Context, StringRef Name, DIType *Ty,
 345                                    Metadata *MD) {
 346   assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
 347   return DITemplateValueParameter::get(VMContext, Tag, Name, DITypeRef::get(Ty),
 348                                        MD);
 349 }
 350
 351 DITemplateValueParameter *
 352 DIBuilder::createTemplateValueParameter(DIScope *Context, StringRef Name,
 353                                         DIType *Ty, Constant *Val) {
 354   return createTemplateValueParameterHelper(
 355       VMContext, dwarf::DW_TAG_template_value_parameter, Context, Name, Ty,
 356       getConstantOrNull(Val));
 357 }
 358
 359 DITemplateValueParameter *
 360 DIBuilder::createTemplateTemplateParameter(DIScope *Context, StringRef Name,
 361                                            DIType *Ty, StringRef Val) {
 362   return createTemplateValueParameterHelper(
 363       VMContext, dwarf::DW_TAG_GNU_template_template_param, Context, Name, Ty,
 364       MDString::get(VMContext, Val));
 365 }
 366
 367 DITemplateValueParameter *
 368 DIBuilder::createTemplateParameterPack(DIScope *Context, StringRef Name,
 369                                        DIType *Ty, DINodeArray Val) {
 370   return createTemplateValueParameterHelper(
 371       VMContext, dwarf::DW_TAG_GNU_template_parameter_pack, Context, Name, Ty,
 372       Val.get());
 373 }
 374
 375 DICompositeType *DIBuilder::createClassType(
 376     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 377     uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits,
 378     unsigned Flags, DIType *DerivedFrom, DINodeArray Elements,
 379     DIType *VTableHolder, MDNode *TemplateParams, StringRef UniqueIdentifier) {
 380   assert((!Context || isa<DIScope>(Context)) &&
 381          "createClassType should be called with a valid Context");
 382
 383   auto *R = DICompositeType::get(
 384       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 385       DIScopeRef::get(getNonCompileUnitScope(Context)),
 386       DITypeRef::get(DerivedFrom), SizeInBits, AlignInBits, OffsetInBits, Flags,
 387       Elements, 0, DITypeRef::get(VTableHolder),
 388       cast_or_null<MDTuple>(TemplateParams), UniqueIdentifier);
 389   if (!UniqueIdentifier.empty())
 390     retainType(R);
 391   trackIfUnresolved(R);
 392   return R;
 393 }
 394
 395 DICompositeType *DIBuilder::createStructType(
 396     DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
 397     uint64_t SizeInBits, uint64_t AlignInBits, unsigned Flags,
 398     DIType *DerivedFrom, DINodeArray Elements, unsigned RunTimeLang,
 399     DIType *VTableHolder, StringRef UniqueIdentifier) {
 400   auto *R = DICompositeType::get(
 401       VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
 402       DIScopeRef::get(getNonCompileUnitScope(Context)),
 403       DITypeRef::get(DerivedFrom), SizeInBits, AlignInBits, 0, Flags, Elements,
 404       RunTimeLang, DITypeRef::get(VTableHolder), nullptr, UniqueIdentifier);
 405   if (!UniqueIdentifier.empty())
 406     retainType(R);
 407   trackIfUnresolved(R);
 408   return R;
 409 }
 410
 411 DICompositeType *DIBuilder::createUnionType(
 412     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 413     uint64_t SizeInBits, uint64_t AlignInBits, unsigned Flags,
 414     DINodeArray Elements, unsigned RunTimeLang, StringRef UniqueIdentifier) {
 415   auto *R = DICompositeType::get(
 416       VMContext, dwarf::DW_TAG_union_type, Name, File, LineNumber,
 417       DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr, SizeInBits,
 418       AlignInBits, 0, Flags, Elements, RunTimeLang, nullptr, nullptr,
 419       UniqueIdentifier);
 420   if (!UniqueIdentifier.empty())
 421     retainType(R);
 422   trackIfUnresolved(R);
 423   return R;
 424 }
 425
 426 DISubroutineType *DIBuilder::createSubroutineType(DIFile *File,
 427                                                   DITypeRefArray ParameterTypes,
 428                                                   unsigned Flags) {
 429   return DISubroutineType::get(VMContext, Flags, ParameterTypes);
 430 }
 431
 432 DICompositeType *DIBuilder::createEnumerationType(
 433     DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
 434     uint64_t SizeInBits, uint64_t AlignInBits, DINodeArray Elements,
 435     DIType *UnderlyingType, StringRef UniqueIdentifier) {
 436   auto *CTy = DICompositeType::get(
 437       VMContext, dwarf::DW_TAG_enumeration_type, Name, File, LineNumber,
 438       DIScopeRef::get(getNonCompileUnitScope(Scope)),
 439       DITypeRef::get(UnderlyingType), SizeInBits, AlignInBits, 0, 0, Elements,
 440       0, nullptr, nullptr, UniqueIdentifier);
 441   AllEnumTypes.push_back(CTy);
 442   if (!UniqueIdentifier.empty())
 443     retainType(CTy);
 444   trackIfUnresolved(CTy);
 445   return CTy;
 446 }
 447
 448 DICompositeType *DIBuilder::createArrayType(uint64_t Size, uint64_t AlignInBits,
 449                                             DIType *Ty,
 450                                             DINodeArray Subscripts) {
 451   auto *R = DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "",
 452                                  nullptr, 0, nullptr, DITypeRef::get(Ty), Size,
 453                                  AlignInBits, 0, 0, Subscripts, 0, nullptr);
 454   trackIfUnresolved(R);
 455   return R;
 456 }
 457
 458 DICompositeType *DIBuilder::createVectorType(uint64_t Size,
 459                                              uint64_t AlignInBits, DIType *Ty,
 460                                              DINodeArray Subscripts) {
 461   auto *R =
 462       DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "", nullptr, 0,
 463                            nullptr, DITypeRef::get(Ty), Size, AlignInBits, 0,
 464                            DINode::FlagVector, Subscripts, 0, nullptr);
 465   trackIfUnresolved(R);
 466   return R;
 467 }
 468
 469 static DIType *createTypeWithFlags(LLVMContext &Context, DIType *Ty,
 470                                    unsigned FlagsToSet) {
 471   auto NewTy = Ty->clone();
 472   NewTy->setFlags(NewTy->getFlags() | FlagsToSet);
 473   return MDNode::replaceWithUniqued(std::move(NewTy));
 474 }
 475
 476 DIType *DIBuilder::createArtificialType(DIType *Ty) {
 477   // FIXME: Restrict this to the nodes where it's valid.
 478   if (Ty->isArtificial())
 479     return Ty;
 480   return createTypeWithFlags(VMContext, Ty, DINode::FlagArtificial);
 481 }
 482
 483 DIType *DIBuilder::createObjectPointerType(DIType *Ty) {
 484   // FIXME: Restrict this to the nodes where it's valid.
 485   if (Ty->isObjectPointer())
 486     return Ty;
 487   unsigned Flags = DINode::FlagObjectPointer | DINode::FlagArtificial;
 488   return createTypeWithFlags(VMContext, Ty, Flags);
 489 }
 490
 491 void DIBuilder::retainType(DIType *T) {
 492   assert(T && "Expected non-null type");
 493   AllRetainTypes.emplace_back(T);
 494 }
 495
 496 DIBasicType *DIBuilder::createUnspecifiedParameter() { return nullptr; }
 497
 498 DICompositeType *
 499 DIBuilder::createForwardDecl(unsigned Tag, StringRef Name, DIScope *Scope,
 500                              DIFile *F, unsigned Line, unsigned RuntimeLang,
 501                              uint64_t SizeInBits, uint64_t AlignInBits,
 502                              StringRef UniqueIdentifier) {
 503   // FIXME: Define in terms of createReplaceableForwardDecl() by calling
 504   // replaceWithUniqued().
 505   auto *RetTy = DICompositeType::get(
 506       VMContext, Tag, Name, F, Line,
 507       DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr, SizeInBits,
 508       AlignInBits, 0, DINode::FlagFwdDecl, nullptr, RuntimeLang, nullptr,
 509       nullptr, UniqueIdentifier);
 510   if (!UniqueIdentifier.empty())
 511     retainType(RetTy);
 512   trackIfUnresolved(RetTy);
 513   return RetTy;
 514 }
 515
 516 DICompositeType *DIBuilder::createReplaceableCompositeType(
 517     unsigned Tag, StringRef Name, DIScope *Scope, DIFile *F, unsigned Line,
 518     unsigned RuntimeLang, uint64_t SizeInBits, uint64_t AlignInBits,
 519     unsigned Flags, StringRef UniqueIdentifier) {
 520   auto *RetTy = DICompositeType::getTemporary(
 521                     VMContext, Tag, Name, F, Line,
 522                     DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr,
 523                     SizeInBits, AlignInBits, 0, Flags, nullptr, RuntimeLang,
 524                     nullptr, nullptr, UniqueIdentifier)
 525                     .release();
 526   if (!UniqueIdentifier.empty())
 527     retainType(RetTy);
 528   trackIfUnresolved(RetTy);
 529   return RetTy;
 530 }
 531
 532 DINodeArray DIBuilder::getOrCreateArray(ArrayRef<Metadata *> Elements) {
 533   return MDTuple::get(VMContext, Elements);
 534 }
 535
 536 DITypeRefArray DIBuilder::getOrCreateTypeArray(ArrayRef<Metadata *> Elements) {
 537   SmallVector<llvm::Metadata *, 16> Elts;
 538   for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
 539     if (Elements[i] && isa<MDNode>(Elements[i]))
 540       Elts.push_back(DITypeRef::get(cast<DIType>(Elements[i])));
 541     else
 542       Elts.push_back(Elements[i]);
 543   }
 544   return DITypeRefArray(MDNode::get(VMContext, Elts));
 545 }
 546
 547 DISubrange *DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Count) {
 548   return DISubrange::get(VMContext, Count, Lo);
 549 }
 550
 551 static void checkGlobalVariableScope(DIScope *Context) {
 552 #ifndef NDEBUG
 553   if (auto *CT =
 554           dyn_cast_or_null<DICompositeType>(getNonCompileUnitScope(Context)))
 555     assert(CT->getIdentifier().empty() &&
 556            "Context of a global variable should not be a type with identifier");
 557 #endif
 558 }
 559
 560 DIGlobalVariable *DIBuilder::createGlobalVariable(
 561     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 562     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, Constant *Val,
 563     MDNode *Decl) {
 564   checkGlobalVariableScope(Context);
 565
 566   auto *N = DIGlobalVariable::get(VMContext, cast_or_null<DIScope>(Context),
 567                                   Name, LinkageName, F, LineNumber,
 568                                   DITypeRef::get(Ty), isLocalToUnit, true, Val,
 569                                   cast_or_null<DIDerivedType>(Decl));
 570   AllGVs.push_back(N);
 571   return N;
 572 }
 573
 574 DIGlobalVariable *DIBuilder::createTempGlobalVariableFwdDecl(
 575     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
 576     unsigned LineNumber, DIType *Ty, bool isLocalToUnit, Constant *Val,
 577     MDNode *Decl) {
 578   checkGlobalVariableScope(Context);
 579
 580   return DIGlobalVariable::getTemporary(
 581              VMContext, cast_or_null<DIScope>(Context), Name, LinkageName, F,
 582              LineNumber, DITypeRef::get(Ty), isLocalToUnit, false, Val,
 583              cast_or_null<DIDerivedType>(Decl))
 584       .release();
 585 }
 586
 587 DILocalVariable *DIBuilder::createLocalVariable(
 588     unsigned Tag, DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNo,
 589     DIType *Ty, bool AlwaysPreserve, unsigned Flags, unsigned ArgNo) {
 590   // FIXME: Why getNonCompileUnitScope()?
 591   // FIXME: Why is "!Context" okay here?
 592   // FIXME: WHy doesn't this check for a subprogram or lexical block (AFAICT
 593   // the only valid scopes)?
 594   DIScope *Context = getNonCompileUnitScope(Scope);
 595
 596   auto *Node = DILocalVariable::get(
 597       VMContext, Tag, cast_or_null<DILocalScope>(Context), Name, File, LineNo,
 598       DITypeRef::get(Ty), ArgNo, Flags);
 599   if (AlwaysPreserve) {
 600     // The optimizer may remove local variable. If there is an interest
 601     // to preserve variable info in such situation then stash it in a
 602     // named mdnode.
 603     DISubprogram *Fn = getDISubprogram(Scope);
 604     assert(Fn && "Missing subprogram for local variable");
 605     PreservedVariables[Fn].emplace_back(Node);
 606   }
 607   return Node;
 608 }
 609
 610 DIExpression *DIBuilder::createExpression(ArrayRef<uint64_t> Addr) {
 611   return DIExpression::get(VMContext, Addr);
 612 }
 613
 614 DIExpression *DIBuilder::createExpression(ArrayRef<int64_t> Signed) {
 615   // TODO: Remove the callers of this signed version and delete.
 616   SmallVector<uint64_t, 8> Addr(Signed.begin(), Signed.end());
 617   return createExpression(Addr);
 618 }
 619
 620 DIExpression *DIBuilder::createBitPieceExpression(unsigned OffsetInBytes,
 621                                                   unsigned SizeInBytes) {
 622   uint64_t Addr[] = {dwarf::DW_OP_bit_piece, OffsetInBytes, SizeInBytes};
 623   return DIExpression::get(VMContext, Addr);
 624 }
 625
 626 DISubprogram *DIBuilder::createFunction(DIScopeRef Context, StringRef Name,
 627                                         StringRef LinkageName, DIFile *File,
 628                                         unsigned LineNo, DISubroutineType *Ty,
 629                                         bool isLocalToUnit, bool isDefinition,
 630                                         unsigned ScopeLine, unsigned Flags,
 631                                         bool isOptimized, Function *Fn,
 632                                         MDNode *TParams, MDNode *Decl) {
 633   // dragonegg does not generate identifier for types, so using an empty map
 634   // to resolve the context should be fine.
 635   DITypeIdentifierMap EmptyMap;
 636   return createFunction(Context.resolve(EmptyMap), Name, LinkageName, File,
 637                         LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine,
 638                         Flags, isOptimized, Fn, TParams, Decl);
 639 }
 640
 641 DISubprogram *DIBuilder::createFunction(DIScope *Context, StringRef Name,
 642                                         StringRef LinkageName, DIFile *File,
 643                                         unsigned LineNo, DISubroutineType *Ty,
 644                                         bool isLocalToUnit, bool isDefinition,
 645                                         unsigned ScopeLine, unsigned Flags,
 646                                         bool isOptimized, Function *Fn,
 647                                         MDNode *TParams, MDNode *Decl) {
 648   assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
 649          "function types should be subroutines");
 650   auto *Node = DISubprogram::get(
 651       VMContext, DIScopeRef::get(getNonCompileUnitScope(Context)), Name,
 652       LinkageName, File, LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine,
 653       nullptr, 0, 0, Flags, isOptimized, Fn, cast_or_null<MDTuple>(TParams),
 654       cast_or_null<DISubprogram>(Decl),
 655       MDTuple::getTemporary(VMContext, None).release());
 656
 657   if (isDefinition)
 658     AllSubprograms.push_back(Node);
 659   trackIfUnresolved(Node);
 660   return Node;
 661 }
 662
 663 DISubprogram *DIBuilder::createTempFunctionFwdDecl(
 664     DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *File,
 665     unsigned LineNo, DISubroutineType *Ty, bool isLocalToUnit,
 666     bool isDefinition, unsigned ScopeLine, unsigned Flags, bool isOptimized,
 667     Function *Fn, MDNode *TParams, MDNode *Decl) {
 668   return DISubprogram::getTemporary(
 669              VMContext, DIScopeRef::get(getNonCompileUnitScope(Context)), Name,
 670              LinkageName, File, LineNo, Ty, isLocalToUnit, isDefinition,
 671              ScopeLine, nullptr, 0, 0, Flags, isOptimized, Fn,
 672              cast_or_null<MDTuple>(TParams), cast_or_null<DISubprogram>(Decl),
 673              nullptr)
 674       .release();
 675 }
 676
 677 DISubprogram *
 678 DIBuilder::createMethod(DIScope *Context, StringRef Name, StringRef LinkageName,
 679                         DIFile *F, unsigned LineNo, DISubroutineType *Ty,
 680                         bool isLocalToUnit, bool isDefinition, unsigned VK,
 681                         unsigned VIndex, DIType *VTableHolder, unsigned Flags,
 682                         bool isOptimized, Function *Fn, MDNode *TParam) {
 683   assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
 684          "function types should be subroutines");
 685   assert(getNonCompileUnitScope(Context) &&
 686          "Methods should have both a Context and a context that isn't "
 687          "the compile unit.");
 688   // FIXME: Do we want to use different scope/lines?
 689   auto *SP = DISubprogram::get(
 690       VMContext, DIScopeRef::get(cast<DIScope>(Context)), Name, LinkageName, F,
 691       LineNo, Ty, isLocalToUnit, isDefinition, LineNo,
 692       DITypeRef::get(VTableHolder), VK, VIndex, Flags, isOptimized, Fn,
 693       cast_or_null<MDTuple>(TParam), nullptr, nullptr);
 694
 695   if (isDefinition)
 696     AllSubprograms.push_back(SP);
 697   trackIfUnresolved(SP);
 698   return SP;
 699 }
 700
 701 DINamespace *DIBuilder::createNameSpace(DIScope *Scope, StringRef Name,
 702                                         DIFile *File, unsigned LineNo) {
 703   return DINamespace::get(VMContext, getNonCompileUnitScope(Scope), File, Name,
 704                           LineNo);
 705 }
 706
 707 DIModule *DIBuilder::createModule(DIScope *Scope, StringRef Name,
 708                                   StringRef ConfigurationMacros,
 709                                   StringRef IncludePath,
 710                                   StringRef ISysRoot) {
 711  return DIModule::get(VMContext, getNonCompileUnitScope(Scope), Name,
 712                       ConfigurationMacros, IncludePath, ISysRoot);
 713 }
 714
 715 DILexicalBlockFile *DIBuilder::createLexicalBlockFile(DIScope *Scope,
 716                                                       DIFile *File,
 717                                                       unsigned Discriminator) {
 718   return DILexicalBlockFile::get(VMContext, Scope, File, Discriminator);
 719 }
 720
 721 DILexicalBlock *DIBuilder::createLexicalBlock(DIScope *Scope, DIFile *File,
 722                                               unsigned Line, unsigned Col) {
 723   // Make these distinct, to avoid merging two lexical blocks on the same
 724   // file/line/column.
 725   return DILexicalBlock::getDistinct(VMContext, getNonCompileUnitScope(Scope),
 726                                      File, Line, Col);
 727 }
 728
 729 static Value *getDbgIntrinsicValueImpl(LLVMContext &VMContext, Value *V) {
 730   assert(V && "no value passed to dbg intrinsic");
 731   return MetadataAsValue::get(VMContext, ValueAsMetadata::get(V));
 732 }
 733
 734 static Instruction *withDebugLoc(Instruction *I, const DILocation *DL) {
 735   I->setDebugLoc(const_cast<DILocation *>(DL));
 736   return I;
 737 }
 738
 739 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 740                                       DIExpression *Expr, const DILocation *DL,
 741                                       Instruction *InsertBefore) {
 742   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
 743   assert(DL && "Expected debug loc");
 744   assert(DL->getScope()->getSubprogram() ==
 745              VarInfo->getScope()->getSubprogram() &&
 746          "Expected matching subprograms");
 747   if (!DeclareFn)
 748     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 749
 750   trackIfUnresolved(VarInfo);
 751   trackIfUnresolved(Expr);
 752   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
 753                    MetadataAsValue::get(VMContext, VarInfo),
 754                    MetadataAsValue::get(VMContext, Expr)};
 755   return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertBefore), DL);
 756 }
 757
 758 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
 759                                       DIExpression *Expr, const DILocation *DL,
 760                                       BasicBlock *InsertAtEnd) {
 761   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
 762   assert(DL && "Expected debug loc");
 763   assert(DL->getScope()->getSubprogram() ==
 764              VarInfo->getScope()->getSubprogram() &&
 765          "Expected matching subprograms");
 766   if (!DeclareFn)
 767     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 768
 769   trackIfUnresolved(VarInfo);
 770   trackIfUnresolved(Expr);
 771   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
 772                    MetadataAsValue::get(VMContext, VarInfo),
 773                    MetadataAsValue::get(VMContext, Expr)};
 774
 775   // If this block already has a terminator then insert this intrinsic
 776   // before the terminator.
 777   if (TerminatorInst *T = InsertAtEnd->getTerminator())
 778     return withDebugLoc(CallInst::Create(DeclareFn, Args, "", T), DL);
 779   return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertAtEnd), DL);
 780 }
 781
 782 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
 783                                                 DILocalVariable *VarInfo,
 784                                                 DIExpression *Expr,
 785                                                 const DILocation *DL,
 786                                                 Instruction *InsertBefore) {
 787   assert(V && "no value passed to dbg.value");
 788   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
 789   assert(DL && "Expected debug loc");
 790   assert(DL->getScope()->getSubprogram() ==
 791              VarInfo->getScope()->getSubprogram() &&
 792          "Expected matching subprograms");
 793   if (!ValueFn)
 794     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
 795
 796   trackIfUnresolved(VarInfo);
 797   trackIfUnresolved(Expr);
 798   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
 799                    ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
 800                    MetadataAsValue::get(VMContext, VarInfo),
 801                    MetadataAsValue::get(VMContext, Expr)};
 802   return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertBefore), DL);
 803 }
 804
 805 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
 806                                                 DILocalVariable *VarInfo,
 807                                                 DIExpression *Expr,
 808                                                 const DILocation *DL,
 809                                                 BasicBlock *InsertAtEnd) {
 810   assert(V && "no value passed to dbg.value");
 811   assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
 812   assert(DL && "Expected debug loc");
 813   assert(DL->getScope()->getSubprogram() ==
 814              VarInfo->getScope()->getSubprogram() &&
 815          "Expected matching subprograms");
 816   if (!ValueFn)
 817     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
 818
 819   trackIfUnresolved(VarInfo);
 820   trackIfUnresolved(Expr);
 821   Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
 822                    ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
 823                    MetadataAsValue::get(VMContext, VarInfo),
 824                    MetadataAsValue::get(VMContext, Expr)};
 825
 826   return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertAtEnd), DL);
 827 }
 828
 829 void DIBuilder::replaceVTableHolder(DICompositeType *&T,
 830                                     DICompositeType *VTableHolder) {
 831   {
 832     TypedTrackingMDRef<DICompositeType> N(T);
 833     N->replaceVTableHolder(DITypeRef::get(VTableHolder));
 834     T = N.get();
 835   }
 836
 837   // If this didn't create a self-reference, just return.
 838   if (T != VTableHolder)
 839     return;
 840
 841   // Look for unresolved operands.  T will drop RAUW support, orphaning any
 842   // cycles underneath it.
 843   if (T->isResolved())
 844     for (const MDOperand &O : T->operands())
 845       if (auto *N = dyn_cast_or_null<MDNode>(O))
 846         trackIfUnresolved(N);
 847 }
 848
 849 void DIBuilder::replaceArrays(DICompositeType *&T, DINodeArray Elements,
 850                               DINodeArray TParams) {
 851   {
 852     TypedTrackingMDRef<DICompositeType> N(T);
 853     if (Elements)
 854       N->replaceElements(Elements);
 855     if (TParams)
 856       N->replaceTemplateParams(DITemplateParameterArray(TParams));
 857     T = N.get();
 858   }
 859
 860   // If T isn't resolved, there's no problem.
 861   if (!T->isResolved())
 862     return;
 863
 864   // If "T" is resolved, it may be due to a self-reference cycle.  Track the
 865   // arrays explicitly if they're unresolved, or else the cycles will be
 866   // orphaned.
 867   if (Elements)
 868     trackIfUnresolved(Elements.get());
 869   if (TParams)
 870     trackIfUnresolved(TParams.get());
 871 }