[DebugInfo] Delete TypedDINodeRef

TypedDINodeRef<T> is a redundant wrapper of Metadata * that is actually a T *.

Accordingly, change DI{Node,Scope,Type}Ref uses to DI{Node,Scope,Type} * or their const variants.
This allows us to delete many resolve() calls that clutter the code.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D61369

llvm-svn: 360108

8 files changed, 72 insertions, 105 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index c4e7edc0858..c80c0314009 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -272,7 +272,7 @@ static const DISubprogram *getQualifiedNameComponents(
     StringRef ScopeName = getPrettyScopeName(Scope);
     if (!ScopeName.empty())
       QualifiedNameComponents.push_back(ScopeName);
-    Scope = Scope->getScope().resolve();
+    Scope = Scope->getScope();
   }
   return ClosestSubprogram;
 }
@@ -308,7 +308,7 @@ struct CodeViewDebug::TypeLoweringScope {
 };
 
 static std::string getFullyQualifiedName(const DIScope *Ty) {
-  const DIScope *Scope = Ty->getScope().resolve();
+  const DIScope *Scope = Ty->getScope();
   return getFullyQualifiedName(Scope, getPrettyScopeName(Ty));
 }
 
@@ -343,7 +343,7 @@ TypeIndex CodeViewDebug::getFuncIdForSubprogram(const DISubprogram *SP) {
   // MSVC.
   StringRef DisplayName = SP->getName().split('<').first;
 
-  const DIScope *Scope = SP->getScope().resolve();
+  const DIScope *Scope = SP->getScope();
   TypeIndex TI;
   if (const auto *Class = dyn_cast_or_null<DICompositeType>(Scope)) {
     // If the scope is a DICompositeType, then this must be a method. Member
@@ -375,7 +375,7 @@ getFunctionOptions(const DISubroutineType *Ty,
   const DIType *ReturnTy = nullptr;
   if (auto TypeArray = Ty->getTypeArray()) {
     if (TypeArray.size())
-      ReturnTy = TypeArray[0].resolve();
+      ReturnTy = TypeArray[0];
   }
 
   if (auto *ReturnDCTy = dyn_cast_or_null<DICompositeType>(ReturnTy)) {
@@ -974,8 +974,7 @@ void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
   // If we have a display name, build the fully qualified name by walking the
   // chain of scopes.
   if (!SP->getName().empty())
-    FuncName =
-        getFullyQualifiedName(SP->getScope().resolve(), SP->getName());
+    FuncName = getFullyQualifiedName(SP->getScope(), SP->getName());
 
   // If our DISubprogram name is empty, use the mangled name.
   if (FuncName.empty())
@@ -1398,7 +1397,7 @@ static bool shouldEmitUdt(const DIType *T) {
 
   // MSVC does not emit UDTs for typedefs that are scoped to classes.
   if (T->getTag() == dwarf::DW_TAG_typedef) {
-    if (DIScope *Scope = T->getScope().resolve()) {
+    if (DIScope *Scope = T->getScope()) {
       switch (Scope->getTag()) {
       case dwarf::DW_TAG_structure_type:
       case dwarf::DW_TAG_class_type:
@@ -1415,7 +1414,7 @@ static bool shouldEmitUdt(const DIType *T) {
     const DIDerivedType *DT = dyn_cast<DIDerivedType>(T);
     if (!DT)
       return true;
-    T = DT->getBaseType().resolve();
+    T = DT->getBaseType();
   }
   return true;
 }
@@ -1428,8 +1427,8 @@ void CodeViewDebug::addToUDTs(const DIType *Ty) {
     return;
 
   SmallVector<StringRef, 5> QualifiedNameComponents;
-  const DISubprogram *ClosestSubprogram = getQualifiedNameComponents(
-      Ty->getScope().resolve(), QualifiedNameComponents);
+  const DISubprogram *ClosestSubprogram =
+      getQualifiedNameComponents(Ty->getScope(), QualifiedNameComponents);
 
   std::string FullyQualifiedName =
       getQualifiedName(QualifiedNameComponents, getPrettyScopeName(Ty));
@@ -1498,8 +1497,7 @@ TypeIndex CodeViewDebug::lowerType(const DIType *Ty, const DIType *ClassTy) {
 }
 
 TypeIndex CodeViewDebug::lowerTypeAlias(const DIDerivedType *Ty) {
-  DITypeRef UnderlyingTypeRef = Ty->getBaseType();
-  TypeIndex UnderlyingTypeIndex = getTypeIndex(UnderlyingTypeRef);
+  TypeIndex UnderlyingTypeIndex = getTypeIndex(Ty->getBaseType());
   StringRef TypeName = Ty->getName();
 
   addToUDTs(Ty);
@@ -1515,14 +1513,14 @@ TypeIndex CodeViewDebug::lowerTypeAlias(const DIDerivedType *Ty) {
 }
 
 TypeIndex CodeViewDebug::lowerTypeArray(const DICompositeType *Ty) {
-  DITypeRef ElementTypeRef = Ty->getBaseType();
-  TypeIndex ElementTypeIndex = getTypeIndex(ElementTypeRef);
+  const DIType *ElementType = Ty->getBaseType();
+  TypeIndex ElementTypeIndex = getTypeIndex(ElementType);
   // IndexType is size_t, which depends on the bitness of the target.
   TypeIndex IndexType = getPointerSizeInBytes() == 8
                             ? TypeIndex(SimpleTypeKind::UInt64Quad)
                             : TypeIndex(SimpleTypeKind::UInt32Long);
 
-  uint64_t ElementSize = getBaseTypeSize(ElementTypeRef) / 8;
+  uint64_t ElementSize = getBaseTypeSize(ElementType) / 8;
 
   // Add subranges to array type.
   DINodeArray Elements = Ty->getElements();
@@ -1783,7 +1781,7 @@ TypeIndex CodeViewDebug::lowerTypeModifier(const DIDerivedType *Ty) {
       break;
     }
     if (IsModifier)
-      BaseTy = cast<DIDerivedType>(BaseTy)->getBaseType().resolve();
+      BaseTy = cast<DIDerivedType>(BaseTy)->getBaseType();
   }
 
   // Check if the inner type will use an LF_POINTER record. If so, the
@@ -1816,8 +1814,8 @@ TypeIndex CodeViewDebug::lowerTypeModifier(const DIDerivedType *Ty) {
 
 TypeIndex CodeViewDebug::lowerTypeFunction(const DISubroutineType *Ty) {
   SmallVector<TypeIndex, 8> ReturnAndArgTypeIndices;
-  for (DITypeRef ArgTypeRef : Ty->getTypeArray())
-    ReturnAndArgTypeIndices.push_back(getTypeIndex(ArgTypeRef));
+  for (const DIType *ArgType : Ty->getTypeArray())
+    ReturnAndArgTypeIndices.push_back(getTypeIndex(ArgType));
 
   // MSVC uses type none for variadic argument.
   if (ReturnAndArgTypeIndices.size() > 1 &&
@@ -1866,7 +1864,7 @@ TypeIndex CodeViewDebug::lowerTypeMemberFunction(const DISubroutineType *Ty,
   TypeIndex ThisTypeIndex;
   if (!IsStaticMethod && ReturnAndArgs.size() > Index) {
     if (const DIDerivedType *PtrTy =
-            dyn_cast_or_null<DIDerivedType>(ReturnAndArgs[Index].resolve())) {
+            dyn_cast_or_null<DIDerivedType>(ReturnAndArgs[Index])) {
       if (PtrTy->getTag() == dwarf::DW_TAG_pointer_type) {
         ThisTypeIndex = getTypeIndexForThisPtr(PtrTy, Ty);
         Index++;
@@ -1964,7 +1962,7 @@ static ClassOptions getCommonClassOptions(const DICompositeType *Ty) {
   // Put the Nested flag on a type if it appears immediately inside a tag type.
   // Do not walk the scope chain. Do not attempt to compute ContainsNestedClass
   // here. That flag is only set on definitions, and not forward declarations.
-  const DIScope *ImmediateScope = Ty->getScope().resolve();
+  const DIScope *ImmediateScope = Ty->getScope();
   if (ImmediateScope && isa<DICompositeType>(ImmediateScope))
     CO |= ClassOptions::Nested;
 
@@ -1977,7 +1975,7 @@ static ClassOptions getCommonClassOptions(const DICompositeType *Ty) {
       CO |= ClassOptions::Scoped;
   } else {
     for (const DIScope *Scope = ImmediateScope; Scope != nullptr;
-         Scope = Scope->getScope().resolve()) {
+         Scope = Scope->getScope()) {
       if (isa<DISubprogram>(Scope)) {
         CO |= ClassOptions::Scoped;
         break;
@@ -2097,7 +2095,7 @@ void CodeViewDebug::collectMemberInfo(ClassInfo &Info,
   // succeeds, and drop the member if that fails.
   assert((DDTy->getOffsetInBits() % 8) == 0 && "Unnamed bitfield member!");
   uint64_t Offset = DDTy->getOffsetInBits();
-  const DIType *Ty = DDTy->getBaseType().resolve();
+  const DIType *Ty = DDTy->getBaseType();
   bool FullyResolved = false;
   while (!FullyResolved) {
     switch (Ty->getTag()) {
@@ -2105,7 +2103,7 @@ void CodeViewDebug::collectMemberInfo(ClassInfo &Info,
     case dwarf::DW_TAG_volatile_type:
       // FIXME: we should apply the qualifier types to the indirect fields
       // rather than dropping them.
-      Ty = cast<DIDerivedType>(Ty)->getBaseType().resolve();
+      Ty = cast<DIDerivedType>(Ty)->getBaseType();
       break;
     default:
       FullyResolved = true;
@@ -2388,7 +2386,7 @@ CodeViewDebug::lowerRecordFieldList(const DICompositeType *Ty) {
 
   // Create nested classes.
   for (const DIType *Nested : Info.NestedTypes) {
-    NestedTypeRecord R(getTypeIndex(DITypeRef(Nested)), Nested->getName());
+    NestedTypeRecord R(getTypeIndex(Nested), Nested->getName());
     ContinuationBuilder.writeMemberType(R);
     MemberCount++;
   }
@@ -2415,10 +2413,7 @@ TypeIndex CodeViewDebug::getVBPTypeIndex() {
   return VBPType;
 }
 
-TypeIndex CodeViewDebug::getTypeIndex(DITypeRef TypeRef, DITypeRef ClassTyRef) {
-  const DIType *Ty = TypeRef.resolve();
-  const DIType *ClassTy = ClassTyRef.resolve();
-
+TypeIndex CodeViewDebug::getTypeIndex(const DIType *Ty, const DIType *ClassTy) {
   // The null DIType is the void type. Don't try to hash it.
   if (!Ty)
     return TypeIndex::Void();
@@ -2461,8 +2456,7 @@ CodeViewDebug::getTypeIndexForThisPtr(const DIDerivedType *PtrTy,
   return recordTypeIndexForDINode(PtrTy, TI, SubroutineTy);
 }
 
-TypeIndex CodeViewDebug::getTypeIndexForReferenceTo(DITypeRef TypeRef) {
-  DIType *Ty = TypeRef.resolve();
+TypeIndex CodeViewDebug::getTypeIndexForReferenceTo(const DIType *Ty) {
   PointerRecord PR(getTypeIndex(Ty),
                    getPointerSizeInBytes() == 8 ? PointerKind::Near64
                                                 : PointerKind::Near32,
@@ -2471,9 +2465,7 @@ TypeIndex CodeViewDebug::getTypeIndexForReferenceTo(DITypeRef TypeRef) {
   return TypeTable.writeLeafType(PR);
 }
 
-TypeIndex CodeViewDebug::getCompleteTypeIndex(DITypeRef TypeRef) {
-  const DIType *Ty = TypeRef.resolve();
-
+TypeIndex CodeViewDebug::getCompleteTypeIndex(const DIType *Ty) {
   // The null DIType is the void type. Don't try to hash it.
   if (!Ty)
     return TypeIndex::Void();
@@ -2484,7 +2476,7 @@ TypeIndex CodeViewDebug::getCompleteTypeIndex(DITypeRef TypeRef) {
   if (Ty->getTag() == dwarf::DW_TAG_typedef)
     (void)getTypeIndex(Ty);
   while (Ty->getTag() == dwarf::DW_TAG_typedef)
-    Ty = cast<DIDerivedType>(Ty)->getBaseType().resolve();
+    Ty = cast<DIDerivedType>(Ty)->getBaseType();
 
   // If this is a non-record type, the complete type index is the same as the
   // normal type index. Just call getTypeIndex.
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
index 93204036617..f190b4a2b95 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
@@ -373,14 +373,14 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
 
   /// Translates the DIType to codeview if necessary and returns a type index
   /// for it.
-  codeview::TypeIndex getTypeIndex(DITypeRef TypeRef,
-                                   DITypeRef ClassTyRef = DITypeRef());
+  codeview::TypeIndex getTypeIndex(const DIType *Ty,
+                                   const DIType *ClassTy = nullptr);
 
   codeview::TypeIndex
   getTypeIndexForThisPtr(const DIDerivedType *PtrTy,
                          const DISubroutineType *SubroutineTy);
 
-  codeview::TypeIndex getTypeIndexForReferenceTo(DITypeRef TypeRef);
+  codeview::TypeIndex getTypeIndexForReferenceTo(const DIType *Ty);
 
   codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP,
                                             const DICompositeType *Class);
@@ -419,7 +419,7 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
   /// use this entry point when generating symbol records. The complete and
   /// incomplete type indices only differ for record types. All other types use
   /// the same index.
-  codeview::TypeIndex getCompleteTypeIndex(DITypeRef TypeRef);
+  codeview::TypeIndex getCompleteTypeIndex(const DIType *Ty);
 
   codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty);
   codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty);
diff --git a/llvm/lib/CodeGen/AsmPrinter/DebugHandlerBase.cpp b/llvm/lib/CodeGen/AsmPrinter/DebugHandlerBase.cpp
index f24dbf148e7..22c28cccd89 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DebugHandlerBase.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DebugHandlerBase.cpp
@@ -140,10 +140,9 @@ DebugHandlerBase::getFunctionLocalOffsetAfterInsn(const MachineInstr *MI) {
 }
 
 /// If this type is derived from a base type then return base type size.
-uint64_t DebugHandlerBase::getBaseTypeSize(const DITypeRef TyRef) {
-  DIType *Ty = TyRef.resolve();
+uint64_t DebugHandlerBase::getBaseTypeSize(const DIType *Ty) {
   assert(Ty);
-  DIDerivedType *DDTy = dyn_cast<DIDerivedType>(Ty);
+  const DIDerivedType *DDTy = dyn_cast<DIDerivedType>(Ty);
   if (!DDTy)
     return Ty->getSizeInBits();
 
@@ -154,7 +153,7 @@ uint64_t DebugHandlerBase::getBaseTypeSize(const DITypeRef TyRef) {
       Tag != dwarf::DW_TAG_restrict_type && Tag != dwarf::DW_TAG_atomic_type)
     return DDTy->getSizeInBits();
 
-  DIType *BaseType = DDTy->getBaseType().resolve();
+  DIType *BaseType = DDTy->getBaseType();
 
   if (!BaseType)
     return 0;
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index d6e8ae1590a..45ae009b189 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -119,7 +119,7 @@ DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
   assert(GV);
 
   auto *GVContext = GV->getScope();
-  auto *GTy = DD->resolve(GV->getType());
+  const DIType *GTy = GV->getType();
 
   // Construct the context before querying for the existence of the DIE in
   // case such construction creates the DIE.
@@ -131,7 +131,7 @@ DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
   DIE *VariableDIE = &createAndAddDIE(GV->getTag(), *ContextDIE, GV);
   DIScope *DeclContext;
   if (auto *SDMDecl = GV->getStaticDataMemberDeclaration()) {
-    DeclContext = resolve(SDMDecl->getScope());
+    DeclContext = SDMDecl->getScope();
     assert(SDMDecl->isStaticMember() && "Expected static member decl");
     assert(GV->isDefinition());
     // We need the declaration DIE that is in the static member's class.
@@ -139,7 +139,7 @@ DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
     addDIEEntry(*VariableDIE, dwarf::DW_AT_specification, *VariableSpecDIE);
     // If the global variable's type is different from the one in the class
     // member type, assume that it's more specific and also emit it.
-    if (GTy != DD->resolve(SDMDecl->getBaseType()))
+    if (GTy != SDMDecl->getBaseType())
       addType(*VariableDIE, GTy);
   } else {
     DeclContext = GV->getScope();
@@ -878,7 +878,7 @@ void DwarfCompileUnit::constructAbstractSubprogramScopeDIE(
     ContextDIE = &getUnitDie();
     getOrCreateSubprogramDIE(SPDecl);
   } else {
-    ContextDIE = getOrCreateContextDIE(resolve(SP->getScope()));
+    ContextDIE = getOrCreateContextDIE(SP->getScope());
     // The scope may be shared with a subprogram that has already been
     // constructed in another CU, in which case we need to construct this
     // subprogram in the same CU.
@@ -927,7 +927,7 @@ DIE *DwarfCompileUnit::constructImportedEntityDIE(
   DIE *IMDie = DIE::get(DIEValueAllocator, (dwarf::Tag)Module->getTag());
   insertDIE(Module, IMDie);
   DIE *EntityDie;
-  auto *Entity = resolve(Module->getEntity());
+  auto *Entity = Module->getEntity();
   if (auto *NS = dyn_cast<DINamespace>(Entity))
     EntityDie = getOrCreateNameSpace(NS);
   else if (auto *M = dyn_cast<DIModule>(Entity))
@@ -1192,7 +1192,7 @@ void DwarfCompileUnit::addAddressExpr(DIE &Die, dwarf::Attribute Attribute,
 void DwarfCompileUnit::applySubprogramAttributesToDefinition(
     const DISubprogram *SP, DIE &SPDie) {
   auto *SPDecl = SP->getDeclaration();
-  auto *Context = resolve(SPDecl ? SPDecl->getScope() : SP->getScope());
+  auto *Context = SPDecl ? SPDecl->getScope() : SP->getScope();
   applySubprogramAttributes(SP, SPDie, includeMinimalInlineScopes());
   addGlobalName(SP->getName(), SPDie, Context);
 }
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index c3dad62f386..a6b6fbf3f0c 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -196,11 +196,11 @@ bool DebugLocDwarfExpression::isFrameRegister(const TargetRegisterInfo &TRI,
 
 bool DbgVariable::isBlockByrefVariable() const {
   assert(getVariable() && "Invalid complex DbgVariable!");
-  return getVariable()->getType().resolve()->isBlockByrefStruct();
+  return getVariable()->getType()->isBlockByrefStruct();
 }
 
 const DIType *DbgVariable::getType() const {
-  DIType *Ty = getVariable()->getType().resolve();
+  DIType *Ty = getVariable()->getType();
   // FIXME: isBlockByrefVariable should be reformulated in terms of complex
   // addresses instead.
   if (Ty->isBlockByrefStruct()) {
@@ -232,13 +232,13 @@ const DIType *DbgVariable::getType() const {
     uint16_t tag = Ty->getTag();
 
     if (tag == dwarf::DW_TAG_pointer_type)
-      subType = resolve(cast<DIDerivedType>(Ty)->getBaseType());
+      subType = cast<DIDerivedType>(Ty)->getBaseType();
 
     auto Elements = cast<DICompositeType>(subType)->getElements();
     for (unsigned i = 0, N = Elements.size(); i < N; ++i) {
       auto *DT = cast<DIDerivedType>(Elements[i]);
       if (getName() == DT->getName())
-        return resolve(DT->getBaseType());
+        return DT->getBaseType();
     }
   }
   return Ty;
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 2c2e6bf54c3..53e2baebbd0 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -218,11 +218,6 @@ public:
   static bool classof(const DbgEntity *N) {
     return N->getDbgEntityID() == DbgVariableKind;
   }
-
-private:
-  template <typename T> T *resolve(TypedDINodeRef<T> Ref) const {
-    return Ref.resolve();
-  }
 };
 
 //===----------------------------------------------------------------------===//
@@ -253,11 +248,6 @@ public:
   static bool classof(const DbgEntity *N) {
     return N->getDbgEntityID() == DbgLabelKind;
   }
-
-private:
-  template <typename T> T *resolve(TypedDINodeRef<T> Ref) const {
-    return Ref.resolve();
-  }
 };
 
 /// Helper used to pair up a symbol and its DWARF compile unit.
@@ -702,11 +692,6 @@ public:
   void emitDebugLocEntryLocation(const DebugLocStream::Entry &Entry,
                                  const DwarfCompileUnit *CU);
 
-  /// Find the MDNode for the given reference.
-  template <typename T> T *resolve(TypedDINodeRef<T> Ref) const {
-    return Ref.resolve();
-  }
-
   void addSubprogramNames(const DICompileUnit &CU, const DISubprogram *SP,
                           DIE &Die);
 
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index 6b641eafc44..0ab0a1ed04c 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -471,9 +471,8 @@ static bool isUnsignedDIType(DwarfDebug *DD, const DIType *Ty) {
     assert(T == dwarf::DW_TAG_typedef || T == dwarf::DW_TAG_const_type ||
            T == dwarf::DW_TAG_volatile_type ||
            T == dwarf::DW_TAG_restrict_type || T == dwarf::DW_TAG_atomic_type);
-    DITypeRef Deriv = DTy->getBaseType();
-    assert(Deriv && "Expected valid base type");
-    return isUnsignedDIType(DD, DD->resolve(Deriv));
+    assert(DTy->getBaseType() && "Expected valid base type");
+    return isUnsignedDIType(DD, DTy->getBaseType());
   }
 
   auto *BTy = cast<DIBasicType>(Ty);
@@ -613,7 +612,7 @@ DIE *DwarfUnit::getOrCreateContextDIE(const DIScope *Context) {
 }
 
 DIE *DwarfUnit::createTypeDIE(const DICompositeType *Ty) {
-  auto *Context = resolve(Ty->getScope());
+  auto *Context = Ty->getScope();
   DIE *ContextDIE = getOrCreateContextDIE(Context);
 
   if (DIE *TyDIE = getDIE(Ty))
@@ -666,15 +665,15 @@ DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
 
   // DW_TAG_restrict_type is not supported in DWARF2
   if (Ty->getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
-    return getOrCreateTypeDIE(resolve(cast<DIDerivedType>(Ty)->getBaseType()));
+    return getOrCreateTypeDIE(cast<DIDerivedType>(Ty)->getBaseType());
 
   // DW_TAG_atomic_type is not supported in DWARF < 5
   if (Ty->getTag() == dwarf::DW_TAG_atomic_type && DD->getDwarfVersion() < 5)
-    return getOrCreateTypeDIE(resolve(cast<DIDerivedType>(Ty)->getBaseType()));
+    return getOrCreateTypeDIE(cast<DIDerivedType>(Ty)->getBaseType());
 
   // Construct the context before querying for the existence of the DIE in case
   // such construction creates the DIE.
-  auto *Context = resolve(Ty->getScope());
+  auto *Context = Ty->getScope();
   DIE *ContextDIE = getOrCreateContextDIE(Context);
   assert(ContextDIE);
 
@@ -721,8 +720,8 @@ std::string DwarfUnit::getParentContextString(const DIScope *Context) const {
   SmallVector<const DIScope *, 1> Parents;
   while (!isa<DICompileUnit>(Context)) {
     Parents.push_back(Context);
-    if (Context->getScope())
-      Context = resolve(Context->getScope());
+    if (const DIScope *S = Context->getScope())
+      Context = S;
     else
       // Structure, etc types will have a NULL context if they're at the top
       // level.
@@ -773,7 +772,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DIDerivedType *DTy) {
   uint16_t Tag = Buffer.getTag();
 
   // Map to main type, void will not have a type.
-  const DIType *FromTy = resolve(DTy->getBaseType());
+  const DIType *FromTy = DTy->getBaseType();
   if (FromTy)
     addType(Buffer, FromTy);
 
@@ -789,9 +788,8 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DIDerivedType *DTy) {
     addUInt(Buffer, dwarf::DW_AT_byte_size, None, Size);
 
   if (Tag == dwarf::DW_TAG_ptr_to_member_type)
-    addDIEEntry(
-        Buffer, dwarf::DW_AT_containing_type,
-        *getOrCreateTypeDIE(resolve(cast<DIDerivedType>(DTy)->getClassType())));
+    addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
+                *getOrCreateTypeDIE(cast<DIDerivedType>(DTy)->getClassType()));
   // Add source line info if available and TyDesc is not a forward declaration.
   if (!DTy->isForwardDecl())
     addSourceLine(Buffer, DTy);
@@ -806,7 +804,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DIDerivedType *DTy) {
 
 void DwarfUnit::constructSubprogramArguments(DIE &Buffer, DITypeRefArray Args) {
   for (unsigned i = 1, N = Args.size(); i < N; ++i) {
-    const DIType *Ty = resolve(Args[i]);
+    const DIType *Ty = Args[i];
     if (!Ty) {
       assert(i == N-1 && "Unspecified parameter must be the last argument");
       createAndAddDIE(dwarf::DW_TAG_unspecified_parameters, Buffer);
@@ -823,7 +821,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DISubroutineType *CTy) {
   // Add return type.  A void return won't have a type.
   auto Elements = cast<DISubroutineType>(CTy)->getTypeArray();
   if (Elements.size())
-    if (auto RTy = resolve(Elements[0]))
+    if (auto RTy = Elements[0])
       addType(Buffer, RTy);
 
   bool isPrototyped = true;
@@ -894,7 +892,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
       else if (auto *DDTy = dyn_cast<DIDerivedType>(Element)) {
         if (DDTy->getTag() == dwarf::DW_TAG_friend) {
           DIE &ElemDie = createAndAddDIE(dwarf::DW_TAG_friend, Buffer);
-          addType(ElemDie, resolve(DDTy->getBaseType()), dwarf::DW_AT_friend);
+          addType(ElemDie, DDTy->getBaseType(), dwarf::DW_AT_friend);
         } else if (DDTy->isStaticMember()) {
           getOrCreateStaticMemberDIE(DDTy);
         } else if (Tag == dwarf::DW_TAG_variant_part) {
@@ -903,7 +901,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
           DIE &Variant = createAndAddDIE(dwarf::DW_TAG_variant, Buffer);
           if (const ConstantInt *CI =
               dyn_cast_or_null<ConstantInt>(DDTy->getDiscriminantValue())) {
-            if (isUnsignedDIType(DD, resolve(Discriminator->getBaseType())))
+            if (isUnsignedDIType(DD, Discriminator->getBaseType()))
               addUInt(Variant, dwarf::DW_AT_discr_value, None, CI->getZExtValue());
             else
               addSInt(Variant, dwarf::DW_AT_discr_value, None, CI->getSExtValue());
@@ -917,7 +915,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
         StringRef PropertyName = Property->getName();
         addString(ElemDie, dwarf::DW_AT_APPLE_property_name, PropertyName);
         if (Property->getType())
-          addType(ElemDie, resolve(Property->getType()));
+          addType(ElemDie, Property->getType());
         addSourceLine(ElemDie, Property);
         StringRef GetterName = Property->getGetterName();
         if (!GetterName.empty())
@@ -943,7 +941,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
     // inside C++ composite types to point to the base class with the vtable.
     // Rust uses DW_AT_containing_type to link a vtable to the type
     // for which it was created.
-    if (auto *ContainingType = resolve(CTy->getVTableHolder()))
+    if (auto *ContainingType = CTy->getVTableHolder())
       addDIEEntry(Buffer, dwarf::DW_AT_containing_type,
                   *getOrCreateTypeDIE(ContainingType));
 
@@ -1013,7 +1011,7 @@ void DwarfUnit::constructTemplateTypeParameterDIE(
       createAndAddDIE(dwarf::DW_TAG_template_type_parameter, Buffer);
   // Add the type if it exists, it could be void and therefore no type.
   if (TP->getType())
-    addType(ParamDIE, resolve(TP->getType()));
+    addType(ParamDIE, TP->getType());
   if (!TP->getName().empty())
     addString(ParamDIE, dwarf::DW_AT_name, TP->getName());
 }
@@ -1025,12 +1023,12 @@ void DwarfUnit::constructTemplateValueParameterDIE(
   // Add the type if there is one, template template and template parameter
   // packs will not have a type.
   if (VP->getTag() == dwarf::DW_TAG_template_value_parameter)
-    addType(ParamDIE, resolve(VP->getType()));
+    addType(ParamDIE, VP->getType());
   if (!VP->getName().empty())
     addString(ParamDIE, dwarf::DW_AT_name, VP->getName());
   if (Metadata *Val = VP->getValue()) {
     if (ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(Val))
-      addConstantValue(ParamDIE, CI, resolve(VP->getType()));
+      addConstantValue(ParamDIE, CI, VP->getType());
     else if (GlobalValue *GV = mdconst::dyn_extract<GlobalValue>(Val)) {
       // We cannot describe the location of dllimport'd entities: the
       // computation of their address requires loads from the IAT.
@@ -1104,7 +1102,7 @@ DIE *DwarfUnit::getOrCreateSubprogramDIE(const DISubprogram *SP, bool Minimal) {
   // such construction creates the DIE (as is the case for member function
   // declarations).
   DIE *ContextDIE =
-      Minimal ? &getUnitDie() : getOrCreateContextDIE(resolve(SP->getScope()));
+      Minimal ? &getUnitDie() : getOrCreateContextDIE(SP->getScope());
 
   if (DIE *SPDie = getDIE(SP))
     return SPDie;
@@ -1217,7 +1215,7 @@ void DwarfUnit::applySubprogramAttributes(const DISubprogram *SP, DIE &SPDie,
   // Add a return type. If this is a type like a C/C++ void type we don't add a
   // return type.
   if (Args.size())
-    if (auto Ty = resolve(Args[0]))
+    if (auto Ty = Args[0])
       addType(SPDie, Ty);
 
   unsigned VK = SP->getVirtuality();
@@ -1229,8 +1227,7 @@ void DwarfUnit::applySubprogramAttributes(const DISubprogram *SP, DIE &SPDie,
       addUInt(*Block, dwarf::DW_FORM_udata, SP->getVirtualIndex());
       addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, Block);
     }
-    ContainingTypeMap.insert(
-        std::make_pair(&SPDie, resolve(SP->getContainingType())));
+    ContainingTypeMap.insert(std::make_pair(&SPDie, SP->getContainingType()));
   }
 
   if (!SP->isDefinition()) {
@@ -1336,7 +1333,7 @@ static bool hasVectorBeenPadded(const DICompositeType *CTy) {
   const uint64_t ActualSize = CTy->getSizeInBits();
 
   // Obtain the size of each element in the vector.
-  DIType *BaseTy = CTy->getBaseType().resolve();
+  DIType *BaseTy = CTy->getBaseType();
   assert(BaseTy && "Unknown vector element type.");
   const uint64_t ElementSize = BaseTy->getSizeInBits();
 
@@ -1364,7 +1361,7 @@ void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
   }
 
   // Emit the element type.
-  addType(Buffer, resolve(CTy->getBaseType()));
+  addType(Buffer, CTy->getBaseType());
 
   // Get an anonymous type for index type.
   // FIXME: This type should be passed down from the front end
@@ -1382,7 +1379,7 @@ void DwarfUnit::constructArrayTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
 }
 
 void DwarfUnit::constructEnumTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
-  const DIType *DTy = resolve(CTy->getBaseType());
+  const DIType *DTy = CTy->getBaseType();
   bool IsUnsigned = DTy && isUnsignedDIType(DD, DTy);
   if (DTy) {
     if (DD->getDwarfVersion() >= 3)
@@ -1426,7 +1423,7 @@ DIE &DwarfUnit::constructMemberDIE(DIE &Buffer, const DIDerivedType *DT) {
   if (!Name.empty())
     addString(MemberDie, dwarf::DW_AT_name, Name);
 
-  if (DIType *Resolved = resolve(DT->getBaseType()))
+  if (DIType *Resolved = DT->getBaseType())
     addType(MemberDie, Resolved);
 
   addSourceLine(MemberDie, DT);
@@ -1535,7 +1532,7 @@ DIE *DwarfUnit::getOrCreateStaticMemberDIE(const DIDerivedType *DT) {
 
   // Construct the context before querying for the existence of the DIE in case
   // such construction creates the DIE.
-  DIE *ContextDIE = getOrCreateContextDIE(resolve(DT->getScope()));
+  DIE *ContextDIE = getOrCreateContextDIE(DT->getScope());
   assert(dwarf::isType(ContextDIE->getTag()) &&
          "Static member should belong to a type.");
 
@@ -1544,7 +1541,7 @@ DIE *DwarfUnit::getOrCreateStaticMemberDIE(const DIDerivedType *DT) {
 
   DIE &StaticMemberDIE = createAndAddDIE(DT->getTag(), *ContextDIE, DT);
 
-  const DIType *Ty = resolve(DT->getBaseType());
+  const DIType *Ty = DT->getBaseType();
 
   addString(StaticMemberDIE, dwarf::DW_AT_name, DT->getName());
   addType(StaticMemberDIE, Ty);
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
index 14a1373aee4..7a17b424199 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
@@ -311,12 +311,6 @@ protected:
   /// create a new ID and insert it in the line table.
   virtual unsigned getOrCreateSourceID(const DIFile *File) = 0;
 
-  /// Look in the DwarfDebug map for the MDNode that corresponds to the
-  /// reference.
-  template <typename T> T *resolve(TypedDINodeRef<T> Ref) const {
-    return Ref.resolve();
-  }
-
   /// Emit the common part of the header for this unit.
   void emitCommonHeader(bool UseOffsets, dwarf::UnitType UT);