lib/IR/DIBuilder.cpp

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