[Debug Info] Remove the mostly unused FragmentType from DebugTypeInfo

This cleanup allows for more consistent debug info emission since we depend less on IRGen magic to emit debug info for types.
2025-12-14 20:36:38 +01:00 · 2025-01-27 17:26:56 -08:00
parent 266fa2af41
commit e70a3443e9
14 changed files with 102 additions and 142 deletions
--- a/lib/IRGen/DebugTypeInfo.cpp
+++ b/lib/IRGen/DebugTypeInfo.cpp
@@ -26,12 +26,11 @@
 using namespace swift;
 using namespace irgen;

-DebugTypeInfo::DebugTypeInfo(swift::Type Ty, llvm::Type *FragmentStorageTy,
-                             Alignment Align, bool HasDefaultAlignment,
-                             bool IsMetadata, bool IsFixedBuffer,
+DebugTypeInfo::DebugTypeInfo(swift::Type Ty, Alignment Align,
+                             bool HasDefaultAlignment, bool IsMetadata,
+                             bool IsFixedBuffer,
                             std::optional<uint32_t> NumExtraInhabitants)
-    : Type(Ty.getPointer()), FragmentStorageType(FragmentStorageTy),
-      NumExtraInhabitants(NumExtraInhabitants),
+    : Type(Ty.getPointer()), NumExtraInhabitants(NumExtraInhabitants),
      Align(Align), DefaultAlignment(HasDefaultAlignment),
      IsMetadataType(IsMetadata), IsFixedBuffer(IsFixedBuffer) {
  assert(Align.getValue() != 0);
@@ -49,15 +48,14 @@ static bool hasDefaultAlignment(swift::Type Ty) {

 DebugTypeInfo DebugTypeInfo::getFromTypeInfo(swift::Type Ty, const TypeInfo &TI,
                                             IRGenModule &IGM) {
-  llvm::Type *StorageType = TI.getStorageType();
  std::optional<uint32_t> NumExtraInhabitants;
  if (TI.isFixedSize()) {
    const FixedTypeInfo &FixTy = *cast<const FixedTypeInfo>(&TI);
    NumExtraInhabitants = FixTy.getFixedExtraInhabitantCount(IGM);
  }
  assert(TI.getStorageType() && "StorageType is a nullptr");
-  return DebugTypeInfo(Ty.getPointer(), StorageType,
-                       TI.getBestKnownAlignment(), ::hasDefaultAlignment(Ty),
+  return DebugTypeInfo(Ty.getPointer(), TI.getBestKnownAlignment(),
+                       ::hasDefaultAlignment(Ty),
                       /* IsMetadataType = */ false,
                       /* IsFixedBuffer = */ false, NumExtraInhabitants);
 }
@@ -81,25 +79,21 @@ DebugTypeInfo DebugTypeInfo::getLocalVariable(VarDecl *Decl, swift::Type Ty,
  return getFromTypeInfo(Type, Info, IGM);
 }

-DebugTypeInfo DebugTypeInfo::getGlobalMetadata(swift::Type Ty,
-                                               llvm::Type *StorageTy, Size size,
+DebugTypeInfo DebugTypeInfo::getGlobalMetadata(swift::Type Ty, Size size,
                                               Alignment align) {
-  DebugTypeInfo DbgTy(Ty.getPointer(), StorageTy, align,
+  DebugTypeInfo DbgTy(Ty.getPointer(), align,
                      /* HasDefaultAlignment = */ true,
                      /* IsMetadataType = */ false);
-  assert(StorageTy && "StorageType is a nullptr");
  assert(!DbgTy.isContextArchetype() &&
         "type metadata cannot contain an archetype");
  return DbgTy;
 }

-DebugTypeInfo DebugTypeInfo::getTypeMetadata(swift::Type Ty,
-                                             llvm::Type *StorageTy, Size size,
+DebugTypeInfo DebugTypeInfo::getTypeMetadata(swift::Type Ty, Size size,
                                             Alignment align) {
-  DebugTypeInfo DbgTy(Ty.getPointer(), StorageTy, align,
+  DebugTypeInfo DbgTy(Ty.getPointer(), align,
                      /* HasDefaultAlignment = */ true,
                      /* IsMetadataType = */ true);
-  assert(StorageTy && "StorageType is a nullptr");
  assert(!DbgTy.isContextArchetype() &&
         "type metadata cannot contain an archetype");
  return DbgTy;
@@ -111,7 +105,6 @@ DebugTypeInfo DebugTypeInfo::getForwardDecl(swift::Type Ty) {
 }

 DebugTypeInfo DebugTypeInfo::getGlobal(SILGlobalVariable *GV,
-                                       llvm::Type *FragmentStorageType,
                                       IRGenModule &IGM) {
  // Prefer the original, potentially sugared version of the type if
  // the type hasn't been mucked with by an optimization pass.
@@ -124,16 +117,14 @@ DebugTypeInfo DebugTypeInfo::getGlobal(SILGlobalVariable *GV,
  }
  auto &TI = IGM.getTypeInfoForUnlowered(Type);
  DebugTypeInfo DbgTy = getFromTypeInfo(Type, TI, IGM);
-  assert(FragmentStorageType && "FragmentStorageType is a nullptr");
  assert(!DbgTy.isContextArchetype() &&
         "type of global variable cannot be an archetype");
  return DbgTy;
 }

-DebugTypeInfo
-DebugTypeInfo::getGlobalFixedBuffer(SILGlobalVariable *GV,
-                                    llvm::Type *FragmentStorageType,
-                                    Size SizeInBytes, Alignment Align) {
+DebugTypeInfo DebugTypeInfo::getGlobalFixedBuffer(SILGlobalVariable *GV,
+                                                  Size SizeInBytes,
+                                                  Alignment Align) {
  // Prefer the original, potentially sugared version of the type if
  // the type hasn't been mucked with by an optimization pass.
  auto LowTy = GV->getLoweredType().getASTType();
@@ -143,23 +134,18 @@ DebugTypeInfo::getGlobalFixedBuffer(SILGlobalVariable *GV,
    if (DeclType->isEqual(LowTy))
      Type = DeclType.getPointer();
  }
-  DebugTypeInfo DbgTy(Type, FragmentStorageType,
-                      Align, ::hasDefaultAlignment(Type),
+  DebugTypeInfo DbgTy(Type, Align, ::hasDefaultAlignment(Type),
                      /* IsMetadataType = */ false, /* IsFixedBuffer = */ true);
-  assert(FragmentStorageType && "FragmentStorageType is a nullptr");
  assert(!DbgTy.isContextArchetype() &&
         "type of global variable cannot be an archetype");
  return DbgTy;
 }

-DebugTypeInfo DebugTypeInfo::getObjCClass(ClassDecl *theClass,
-                                          llvm::Type *FragmentStorageType,
-                                          Size SizeInBytes, Alignment align) {
-  DebugTypeInfo DbgTy(theClass->getInterfaceType().getPointer(),
-                      FragmentStorageType, align,
+DebugTypeInfo DebugTypeInfo::getObjCClass(ClassDecl *theClass, Size SizeInBytes,
+                                          Alignment align) {
+  DebugTypeInfo DbgTy(theClass->getInterfaceType().getPointer(), align,
                      /* HasDefaultAlignment = */ true,
                      /* IsMetadataType = */ false);
-  assert(FragmentStorageType && "FragmentStorageType is a nullptr");
  assert(!DbgTy.isContextArchetype() &&
         "type of objc class cannot be an archetype");
  return DbgTy;
@@ -194,7 +180,7 @@ TypeDecl *DebugTypeInfo::getDecl() const {
 }

 bool DebugTypeInfo::isForwardDecl() const {
-  return isNull() || (!FragmentStorageType && !isa<TypeAliasType>(getType()));
+  return isNull() || (!isa<TypeAliasType>(getType()));
 }

 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
@@ -204,17 +190,14 @@ LLVM_DUMP_METHOD void DebugTypeInfo::dump() const {
  if (auto *Type = getType())
    Type->dump(llvm::errs());

-  if (FragmentStorageType) {
-    llvm::errs() << "FragmentStorageType=";
-    FragmentStorageType->dump();
-  }
  if (isForwardDecl())
    llvm::errs() << "forward-declared\n";
 }
 #endif

 std::optional<CompletedDebugTypeInfo>
-CompletedDebugTypeInfo::getFromTypeInfo(swift::Type Ty, const TypeInfo &Info, IRGenModule &IGM) {
+CompletedDebugTypeInfo::getFromTypeInfo(swift::Type Ty, const TypeInfo &Info,
+                                        IRGenModule &IGM) {
  auto *StorageType = IGM.getStorageTypeForUnlowered(Ty);
  std::optional<uint64_t> SizeInBits;
  if (StorageType->isSized())
--- a/lib/IRGen/DebugTypeInfo.h
+++ b/lib/IRGen/DebugTypeInfo.h
@@ -43,7 +43,6 @@ protected:
  TypeBase *Type = nullptr;
  /// Needed to determine the size of basic types and to determine
  /// the storage type for undefined variables.
-  llvm::Type *FragmentStorageType = nullptr;
  std::optional<uint32_t> NumExtraInhabitants;
  Alignment Align;
  bool DefaultAlignment = true;
@@ -52,8 +51,7 @@ protected:

 public:
  DebugTypeInfo() = default;
-  DebugTypeInfo(swift::Type Ty, llvm::Type *StorageTy = nullptr,
-                Alignment AlignInBytes = Alignment(1),
+  DebugTypeInfo(swift::Type Ty, Alignment AlignInBytes = Alignment(1),
                bool HasDefaultAlignment = true, bool IsMetadataType = false,
                bool IsFixedBuffer = false,
                std::optional<uint32_t> NumExtraInhabitants = {});
@@ -62,11 +60,11 @@ public:
  static DebugTypeInfo getLocalVariable(VarDecl *Decl, swift::Type Ty,
                                        const TypeInfo &Info, IRGenModule &IGM);
  /// Create type for global type metadata.
-  static DebugTypeInfo getGlobalMetadata(swift::Type Ty, llvm::Type *StorageTy,
-                                         Size size, Alignment align);
+  static DebugTypeInfo getGlobalMetadata(swift::Type Ty, Size size,
+                                         Alignment align);
  /// Create type for an artificial metadata variable.
-  static DebugTypeInfo getTypeMetadata(swift::Type Ty, llvm::Type *StorageTy,
-                                       Size size, Alignment align);
+  static DebugTypeInfo getTypeMetadata(swift::Type Ty, Size size,
+                                       Alignment align);

  /// Create a forward declaration for a type whose size is unknown.
  static DebugTypeInfo getForwardDecl(swift::Type Ty);
@@ -75,14 +73,11 @@ public:
  static DebugTypeInfo getFromTypeInfo(swift::Type Ty, const TypeInfo &Info,
                                       IRGenModule &IGM);
  /// Global variables.
-  static DebugTypeInfo getGlobal(SILGlobalVariable *GV,
-                                 llvm::Type *StorageType, IRGenModule &IGM);
+  static DebugTypeInfo getGlobal(SILGlobalVariable *GV, IRGenModule &IGM);
  static DebugTypeInfo getGlobalFixedBuffer(SILGlobalVariable *GV,
-                                            llvm::Type *StorageType,
                                            Size SizeInBytes, Alignment align);
  /// ObjC classes.
-  static DebugTypeInfo getObjCClass(ClassDecl *theClass,
-                                    llvm::Type *StorageType, Size size,
+  static DebugTypeInfo getObjCClass(ClassDecl *theClass, Size size,
                                    Alignment align);
  /// Error type.
  static DebugTypeInfo getErrorResult(swift::Type Ty, IRGenModule &IGM);
@@ -100,7 +95,6 @@ public:
    return false;
  }

-  llvm::Type *getFragmentStorageType() const { return FragmentStorageType; }
  Alignment getAlignment() const { return Align; }
  bool isNull() const { return !Type; }
  bool isForwardDecl() const;
@@ -151,7 +145,7 @@ template <> struct DenseMapInfo<swift::irgen::DebugTypeInfo> {
  }
  static swift::irgen::DebugTypeInfo getTombstoneKey() {
    return swift::irgen::DebugTypeInfo(
-        llvm::DenseMapInfo<swift::TypeBase *>::getTombstoneKey(), nullptr,
+        llvm::DenseMapInfo<swift::TypeBase *>::getTombstoneKey(),
        swift::irgen::Alignment(), /* HasDefaultAlignment = */ false);
  }
  static unsigned getHashValue(swift::irgen::DebugTypeInfo Val) {
--- a/lib/IRGen/GenDecl.cpp
+++ b/lib/IRGen/GenDecl.cpp
@@ -2741,10 +2741,9 @@ Address IRGenModule::getAddrOfSILGlobalVariable(SILGlobalVariable *var,
      }

      DebugTypeInfo DbgTy =
-          inFixedBuffer
-              ? DebugTypeInfo::getGlobalFixedBuffer(
-                    var, globalTy, fixedSize, fixedAlignment)
-              : DebugTypeInfo::getGlobal(var, globalTy, *this);
+          inFixedBuffer ? DebugTypeInfo::getGlobalFixedBuffer(var, fixedSize,
+                                                              fixedAlignment)
+                        : DebugTypeInfo::getGlobal(var, *this);

      gvar = createVariable(*this, link, globalTy, fixedAlignment, DbgTy, loc, name);
    }
@@ -4738,8 +4737,8 @@ Address IRGenModule::getAddrOfObjCClassRef(ClassDecl *theClass) {
  assert(ObjCInterop && "getting address of ObjC class ref in no-interop mode");

  LinkEntity entity = LinkEntity::forObjCClassRef(theClass);
-  auto DbgTy = DebugTypeInfo::getObjCClass(
-      theClass, ObjCClassPtrTy, getPointerSize(), getPointerAlignment());
+  auto DbgTy = DebugTypeInfo::getObjCClass(theClass, getPointerSize(),
+                                           getPointerAlignment());
  auto addr = getAddrOfLLVMVariable(entity, ConstantInit(), DbgTy);

  // Define it lazily.
@@ -4764,8 +4763,8 @@ llvm::Constant *IRGenModule::getAddrOfObjCClass(ClassDecl *theClass,
  assert(ObjCInterop && "getting address of ObjC class in no-interop mode");
  assert(!theClass->isForeign());
  LinkEntity entity = LinkEntity::forObjCClass(theClass);
-  auto DbgTy = DebugTypeInfo::getObjCClass(
-      theClass, ObjCClassPtrTy, getPointerSize(), getPointerAlignment());
+  auto DbgTy = DebugTypeInfo::getObjCClass(theClass, getPointerSize(),
+                                           getPointerAlignment());
  auto addr = getAddrOfLLVMVariable(entity, forDefinition, DbgTy);
  return addr;
 }
@@ -4784,8 +4783,8 @@ IRGenModule::getAddrOfMetaclassObject(ClassDecl *decl,
                    ? LinkEntity::forObjCMetaclass(decl)
                    : LinkEntity::forSwiftMetaclassStub(decl);

-  auto DbgTy = DebugTypeInfo::getObjCClass(
-      decl, ObjCClassPtrTy, getPointerSize(), getPointerAlignment());
+  auto DbgTy = DebugTypeInfo::getObjCClass(decl, getPointerSize(),
+                                           getPointerAlignment());
  auto addr = getAddrOfLLVMVariable(entity, forDefinition, DbgTy);
  return addr;
 }
@@ -4800,8 +4799,8 @@ IRGenModule::getAddrOfCanonicalSpecializedGenericMetaclassObject(
  auto entity =
      LinkEntity::forSpecializedGenericSwiftMetaclassStub(concreteType);

-  auto DbgTy = DebugTypeInfo::getObjCClass(
-      theClass, ObjCClassPtrTy, getPointerSize(), getPointerAlignment());
+  auto DbgTy = DebugTypeInfo::getObjCClass(theClass, getPointerSize(),
+                                           getPointerAlignment());
  auto addr = getAddrOfLLVMVariable(entity, forDefinition, DbgTy);
  return addr;
 }
@@ -5149,10 +5148,8 @@ llvm::GlobalValue *IRGenModule::defineTypeMetadata(
                                         TypeMetadataAddress::AddressPoint);
  }

-  auto DbgTy = DebugTypeInfo::getGlobalMetadata(
-      MetatypeType::get(concreteType),
-      entity.getDefaultDeclarationType(*this)->getPointerTo(), Size(0),
-      Alignment(1));
+  auto DbgTy = DebugTypeInfo::getGlobalMetadata(MetatypeType::get(concreteType),
+                                                Size(0), Alignment(1));

  // Define the variable.
  llvm::GlobalVariable *var = cast<llvm::GlobalVariable>(
@@ -5316,7 +5313,6 @@ IRGenModule::getAddrOfTypeMetadata(CanType concreteType,
    break;
  }
  DbgTy = DebugTypeInfo::getGlobalMetadata(MetatypeType::get(concreteType),
-                                           defaultVarTy->getPointerTo(),
                                           Size(0), Alignment(1));

  ConstantReference addr;
--- a/lib/IRGen/GenInit.cpp
+++ b/lib/IRGen/GenInit.cpp
@@ -44,7 +44,7 @@ void IRGenModule::emitSILGlobalVariable(SILGlobalVariable *var) {
  // variable directly, don't actually emit it; just return undef.
  if (ti.isKnownEmpty(expansion)) {
    if (DebugInfo && var->getDecl()) {
-      auto DbgTy = DebugTypeInfo::getGlobal(var, Int8Ty, *this);
+      auto DbgTy = DebugTypeInfo::getGlobal(var, *this);
      DebugInfo->emitGlobalVariableDeclaration(nullptr, var->getDecl()->getName().str(),
                                               "", DbgTy,
                                               var->getLinkage() != SILLinkage::Public &&
--- a/lib/IRGen/IRGenDebugInfo.cpp
+++ b/lib/IRGen/IRGenDebugInfo.cpp
@@ -1475,24 +1475,14 @@ private:
  }

  llvm::DIType *getOrCreateDesugaredType(Type Ty, DebugTypeInfo DbgTy) {
-    DebugTypeInfo BlandDbgTy(Ty, DbgTy.getFragmentStorageType(),
-                             DbgTy.getAlignment(), DbgTy.hasDefaultAlignment(),
+    DebugTypeInfo BlandDbgTy(Ty, DbgTy.getAlignment(),
+                             DbgTy.hasDefaultAlignment(),
                             DbgTy.isMetadataType(), DbgTy.isFixedBuffer());
    return getOrCreateType(BlandDbgTy);
  }

  uint64_t getSizeOfBasicType(CompletedDebugTypeInfo DbgTy) {
    uint64_t BitWidth = DbgTy.getSizeInBits();
-    llvm::Type *StorageType = DbgTy.getFragmentStorageType()
-                                  ? DbgTy.getFragmentStorageType()
-                                  : IGM.DataLayout.getSmallestLegalIntType(
-                                        IGM.getLLVMContext(), BitWidth);
-
-    if (StorageType)
-      return IGM.DataLayout.getTypeSizeInBits(StorageType);
-
-    // This type is too large to fit in a register.
-    assert(BitWidth > IGM.DataLayout.getLargestLegalIntTypeSizeInBits());
    return BitWidth;
  }

@@ -1732,8 +1722,7 @@ private:

  bool shouldCacheDIType(llvm::DIType *DITy, DebugTypeInfo &DbgTy) {
    // Don't cache a type alias to a forward declaration either.
-    if (DbgTy.isForwardDecl() || DbgTy.isFixedBuffer() ||
-        DITy->isForwardDecl())
+    if (DbgTy.isFixedBuffer() || DITy->isForwardDecl())
      return false;

    if (auto Ty = DbgTy.getType())
@@ -1744,6 +1733,14 @@ private:
    return true;
  }

+  std::optional<CompletedDebugTypeInfo> completeType(DebugTypeInfo DbgTy) {
+    if (!DbgTy.getType() || DbgTy.getType()->hasTypeParameter() ||
+        isa<IntegerType>(DbgTy.getType()))
+      return {};
+    return CompletedDebugTypeInfo::getFromTypeInfo(
+        DbgTy.getType(), IGM.getTypeInfoForUnlowered(DbgTy.getType()), IGM);
+  }
+
  llvm::DIType *createType(DebugTypeInfo DbgTy, StringRef MangledName,
                           llvm::DIScope *Scope, llvm::DIFile *File) {
    // FIXME: For SizeInBits, clang uses the actual size of the type on
@@ -1752,8 +1749,7 @@ private:
    // emitting the storage size of the struct, but it may be necessary
    // to emit the (target!) size of the underlying basic type.
    uint64_t SizeOfByte = CI.getTargetInfo().getCharWidth();
-    auto CompletedDbgTy = CompletedDebugTypeInfo::getFromTypeInfo(
-      DbgTy.getType(), IGM.getTypeInfoForUnlowered(DbgTy.getType()), IGM);
+    std::optional<CompletedDebugTypeInfo> CompletedDbgTy = completeType(DbgTy);
    std::optional<uint64_t> SizeInBitsOrNull;
    if (CompletedDbgTy)
      SizeInBitsOrNull = CompletedDbgTy->getSizeInBits();
@@ -1791,8 +1787,9 @@ private:
    case TypeKind::BuiltinFixedArray: {
      // TODO: provide proper array debug info
      unsigned FwdDeclLine = 0;
-      return createOpaqueStruct(Scope, "Builtin.FixedArray", MainFile, FwdDeclLine,
-                                SizeInBits, AlignInBits, Flags, MangledName);
+      return createOpaqueStruct(Scope, "Builtin.FixedArray", MainFile,
+                                FwdDeclLine, SizeInBits, AlignInBits, Flags,
+                                MangledName);
    }

    case TypeKind::BuiltinPackIndex:
@@ -1832,7 +1829,6 @@ private:
            llvm::dwarf::DW_LANG_Swift, nullptr, {}, nullptr,
            NumExtraInhabitants);
        return PTy;
-
      }
      llvm::DIDerivedType *PTy = DBuilder.createPointerType(
          nullptr, PtrSize, 0,
@@ -1862,8 +1858,8 @@ private:
      auto *Decl = StructTy->getDecl();
      auto L = getFileAndLocation(Decl);
      // No line numbers are attached to type forward declarations.  This is
-      // intentional: It interferes with the efficacy of incremental builds. We
-      // don't want a whitespace change to an secondary file trigger a
+      // intentional: It interferes with the efficacy of incremental builds.
+      // We don't want a whitespace change to an secondary file trigger a
      // recompilation of the debug info of a primary source file.
      unsigned FwdDeclLine = 0;
      if (Opts.DebugInfoLevel > IRGenDebugInfoLevel::ASTTypes) {
@@ -1999,14 +1995,11 @@ private:

    case TypeKind::Pack:
    case TypeKind::PackElement:
-      llvm_unreachable("Unimplemented!");
-
    case TypeKind::SILPack:
    case TypeKind::PackExpansion:
-      //assert(SizeInBits == CI.getTargetInfo().getPointerWidth(0));
-      return createPointerSizedStruct(Scope,
-                                      MangledName,
-                                      MainFile, 0, Flags, MangledName);
+      // assert(SizeInBits == CI.getTargetInfo().getPointerWidth(0));
+      return createPointerSizedStruct(Scope, MangledName, MainFile, 0, Flags,
+                                      MangledName);

    case TypeKind::BuiltinTuple:
      llvm_unreachable("BuiltinTupleType should not show up here");
@@ -2032,8 +2025,8 @@ private:
    case TypeKind::PackArchetype: {
      auto *Archetype = BaseTy->castTo<ArchetypeType>();
      AssociatedTypeDecl *assocType = nullptr;
-      if (auto depMemTy = Archetype->getInterfaceType()
-              ->getAs<DependentMemberType>())
+      if (auto depMemTy =
+              Archetype->getInterfaceType()->getAs<DependentMemberType>())
        assocType = depMemTy->getAssocType();
      auto L = getFileAndLocation(assocType);
      if (!L.File)
@@ -2057,9 +2050,9 @@ private:

        auto PTy =
            IGM.getLoweredType(ProtocolDecl->getInterfaceType()).getASTType();
-        auto PDbgTy = DebugTypeInfo::getFromTypeInfo(
-            ProtocolDecl->getInterfaceType(), IGM.getTypeInfoForLowered(PTy),
-            IGM);
+        auto PDbgTy =
+            DebugTypeInfo::getFromTypeInfo(ProtocolDecl->getInterfaceType(),
+                                           IGM.getTypeInfoForLowered(PTy), IGM);
        auto PDITy = getOrCreateType(PDbgTy);
        Protocols.push_back(
            DBuilder.createInheritance(FwdDecl.get(), PDITy, 0, 0, Flags));
@@ -2178,8 +2171,7 @@ private:
      // For TypeAlias types, the DeclContext for the aliased type is
      // in the decl of the alias type.
      DebugTypeInfo AliasedDbgTy(
-          AliasedTy, DbgTy.getFragmentStorageType(),
-          DbgTy.getAlignment(), DbgTy.hasDefaultAlignment(),
+          AliasedTy, DbgTy.getAlignment(), DbgTy.hasDefaultAlignment(),
          /* IsMetadataType = */ false, DbgTy.isFixedBuffer(),
          DbgTy.getNumExtraInhabitants());
      return DBuilder.createTypedef(getOrCreateType(AliasedDbgTy), MangledName,
@@ -2277,16 +2269,17 @@ private:
    // so skip the sanity check.
    if (CachedType->isTemporary())
      return true;
-    if (DbgTy.isForwardDecl())
-      return true;
-    auto CompletedDbgTy = CompletedDebugTypeInfo::getFromTypeInfo(
-      DbgTy.getType(), IGM.getTypeInfoForUnlowered(DbgTy.getType()), IGM);
    std::optional<uint64_t> SizeInBits;
+    std::optional<CompletedDebugTypeInfo> CompletedDbgTy = completeType(DbgTy);
    if (CompletedDbgTy)
      SizeInBits = CompletedDbgTy->getSizeInBits();
    unsigned CachedSizeInBits = getSizeInBits(CachedType);
-    if ((SizeInBits && CachedSizeInBits != *SizeInBits) ||
-        (!SizeInBits && CachedSizeInBits)) {
+    if (SizeInBits && CachedSizeInBits != *SizeInBits) {
+      // Note that CachedSizeInBits && !SizeInBits may happen and is benign,
+      // because the cached copy would win. When the sizeless type is generated
+      // it should be emitted as a forward declaration and thus never make it
+      // into the cache.
+
      // In some situation a specialized type is emitted with size 0, even if
      // the real type has a size.
      if (DbgTy.getType()->isSpecialized() && SizeInBits && *SizeInBits > 0 &&
@@ -2511,7 +2504,8 @@ private:

    // If this is a forward decl, create one for this mangled name and don't
    // cache it.
-    if (DbgTy.isForwardDecl()) {
+    if (!isa<PrimaryArchetypeType>(DbgTy.getType()) &&
+        (DbgTy.isFixedBuffer() || !completeType(DbgTy))) {
      // In LTO type uniquing is performed based on the UID. Forward
      // declarations may not have a unique ID to avoid a forward declaration
      // winning over a full definition.
@@ -2529,7 +2523,7 @@ private:


    if (!shouldCacheDIType(DITy, DbgTy))
-        return  DITy;
+      return DITy;

    // Incrementally build the DIRefMap.
    if (auto *CTy = dyn_cast<llvm::DICompositeType>(DITy)) {
@@ -3731,7 +3725,7 @@ void IRGenDebugInfoImpl::emitTypeMetadata(IRGenFunction &IGF,
  assert(PtrWidthInBits % 8 == 0);
  auto DbgTy = DebugTypeInfo::getTypeMetadata(
      getMetadataType(Name)->getDeclaredInterfaceType().getPointer(),
-      Metadata->getType(), Size(PtrWidthInBits / 8),
+      Size(PtrWidthInBits / 8),
      Alignment(CI.getTargetInfo().getPointerAlign(clang::LangAS::Default)));
  emitVariableDeclaration(IGF.Builder, Metadata, DbgTy, IGF.getDebugScope(),
                          {}, {OS.str().str(), 0, false},
--- a/test/DebugInfo/BoundGenericStruct.swift
+++ b/test/DebugInfo/BoundGenericStruct.swift
@@ -10,7 +10,7 @@ public let s = S<Int>(t: 0)
 // CHECK-SAME:             templateParams: ![[PARAMS:[0-9]+]]
 // CHECK: ![[PARAMS]] = !{![[INTPARAM:[0-9]+]]}
 // CHECK: ![[INTPARAM]] = !DITemplateTypeParameter(type: ![[INT:[0-9]+]])
-// CHECK: ![[INT]] = !DICompositeType(tag: DW_TAG_structure_type, name: "$sSiD",
+// CHECK: ![[INT]] = !DICompositeType(tag: DW_TAG_structure_type, {{.*}}identifier: "$sSiD"


 // DWARF: !DICompositeType(tag: DW_TAG_structure_type,
@@ -56,4 +56,4 @@ public let inner = S2<Double>.Inner(t:4.2)

 // DWARF: ![[ELEMENTS1]] = !{![[ELEMENTS2:[0-9]+]]}

-// DWARF: ![[ELEMENTS2]] = !DIDerivedType(tag: DW_TAG_member, name: "t", scope: !27, file: !3, baseType: ![[GENERIC_PARAM_TYPE]])
+// DWARF: ![[ELEMENTS2]] = !DIDerivedType(tag: DW_TAG_member, name: "t", {{.*}}, baseType: ![[GENERIC_PARAM_TYPE]])
--- a/test/DebugInfo/PrivateDiscriminator.swift
+++ b/test/DebugInfo/PrivateDiscriminator.swift
@@ -7,7 +7,7 @@
 // RUN: %target-swift-frontend %S/../Inputs/empty.swift -primary-file %s \
 // RUN:   -emit-ir -g | %FileCheck %s
 // CHECK: !DICompileUnit({{.*}}flags: {{[^,]*}}-private-discriminator [[DISCRIMINATOR:_[A-Z0-9]+]]
-// CHECK: ![[MOD:.*]] = !DIModule(scope: null,
+// CHECK: ![[MOD:.*]] = !DIModule(scope: null, name: "empty"
 // CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "InA",
 // CHECK-SAME:             scope: ![[A:[0-9]+]],
 // CHECK: ![[A]] = !DICompositeType(tag: DW_TAG_structure_type, name: "A",
--- a/test/DebugInfo/fnptr.swift
+++ b/test/DebugInfo/fnptr.swift
@@ -27,7 +27,7 @@ func main() -> Int64 {
    // CHECK-DAG: ![[BAZPTR]] = !DIDerivedType(tag: DW_TAG_pointer_type,{{.*}} baseType: ![[BAZT:[0-9]+]]
    // CHECK-DAG: ![[BAZT]] = !DISubroutineType(types: ![[BAZARGS:.*]])
    // CHECK-DAG: ![[BAZARGS]] = !{![[INT:.*]], ![[FLOAT:.*]]}
-    // CHECK-DAG: ![[INT]] = {{.*}}name: "$ss5Int64VD"
+    // CHECK-DAG: ![[INT]] = {{.*}}identifier: "$ss5Int64VD"
    // CHECK-DAG: ![[FLOAT]] = {{.*}}identifier: "$sSfD"
    var baz_fnptr = baz
    baz_fnptr(2.89)
--- a/test/DebugInfo/generic_arg5.swift
+++ b/test/DebugInfo/generic_arg5.swift
@@ -12,17 +12,14 @@ public func foo<Type>(_ values : [S<Type>])
  // CHECK-SAME:       ![[ARG:[0-9]+]],
  // CHECK-SAME:       !DIExpression(DW_OP_deref)
  // CHECK: store ptr %1, ptr %[[ALLOCA]], align
-  // CHECK: ![[TYP:[0-9]+]] = !DICompositeType({{.*}}, name: "$s12generic_arg51SVyxGD"
+  // CHECK-DAG: ![[TYP:[0-9]+]] = !DICompositeType({{.*}}, name: "$s12generic_arg51SVyxGD"
  // The argument is a by-ref struct and thus needs to be dereferenced.
-  // CHECK: ![[ARG]] = !DILocalVariable(name: "arg", arg: 1,
-  // CHECK-SAME:                        line: [[@LINE+8]],
-  // CHECK-SAME:                        type: ![[LET_TYP:[0-9]+]])
-  // CHECK: ![[LET_TYP]] = !DIDerivedType(tag: DW_TAG_const_type,
-  // CHECK-SAME:                          baseType: ![[TYP_CONTAINER:[0-9]+]])
-  // CHECK: ![[TYP_CONTAINER]] = !DICompositeType({{.*}}elements: ![[TYP_ELTS:[0-9]+]]
-  // CHECK: ![[TYP_ELTS]] = !{![[TYP_MEMBER:[0-9]+]]}
-  // CHECK: ![[TYP_MEMBER]] = !DIDerivedType(tag: DW_TAG_member, {{.*}}baseType: ![[TYP_:[0-9]+]]
-  // CHECK: ![[TYP_]] = !DICompositeType({{.*}}, name: "$s12generic_arg51SVyxGD"
+  // CHECK-DAG: ![[ARG]] = !DILocalVariable(name: "arg", arg: 1,{{.*}}line: [[@LINE+6]],{{.*}} type: ![[LET_TYP:[0-9]+]])
+  // CHECK-DAG: ![[LET_TYP]] = !DIDerivedType(tag: DW_TAG_const_type,{{.*}} baseType: ![[TYP_CONTAINER:[0-9]+]])
+  // CHECK-DAG: ![[TYP_CONTAINER]] = !DICompositeType({{.*}}elements: ![[TYP_ELTS:[0-9]+]]
+  // CHECK-DAG: ![[TYP_ELTS]] = !{![[TYP_MEMBER:[0-9]+]]}
+  // CHECK-DAG: ![[TYP_MEMBER]] = !DIDerivedType(tag: DW_TAG_member, {{.*}}baseType: ![[TYP_:[0-9]+]]
+  // CHECK-DAG: ![[TYP_]] = !DICompositeType({{.*}}, name: "$s12generic_arg51SVyxGD"
  let _ = values.flatMap { arg in
    return .some(arg)
  }
--- a/test/DebugInfo/local_type_originally_defined_in.swift
+++ b/test/DebugInfo/local_type_originally_defined_in.swift
@@ -7,7 +7,7 @@ import local_type_originally_defined_in_other

 public func definedInOtherModule() {
  let s = Sheep()
-  // CHECK: DICompositeType(tag: DW_TAG_structure_type, name: "Sheep"{{.*}}identifier: "$s4Barn5SheepCD
+  // CHECK-DAG: DICompositeType(tag: DW_TAG_structure_type, name: "Sheep"{{.*}}identifier: "$s4Barn5SheepCD
 }
 public func localTypeAliasTest(horse: Horse) {
  // The local type mangling for 'A' mentions 'Horse', which must
@@ -18,7 +18,7 @@ public func localTypeAliasTest(horse: Horse) {

  let info = UnsafeMutablePointer<A>.allocate(capacity: 1)
  _ = info
-  // CHECK: DIDerivedType(tag: DW_TAG_typedef, name: "$s32local_type_originally_defined_in0A13TypeAliasTest5horsey4Barn5HorseV_tF1AL_aD"
+  // CHECK-DAG: DIDerivedType(tag: DW_TAG_typedef, name: "$s32local_type_originally_defined_in0A13TypeAliasTest5horsey4Barn5HorseV_tF1AL_aD"
 }


@@ -31,7 +31,7 @@ public func localTypeTest(horse: Horse) {

  let info = UnsafeMutablePointer<LocalStruct>.allocate(capacity: 1)
  _ = info
-  // CHECK: DICompositeType(tag: DW_TAG_structure_type, name: "$s32local_type_originally_defined_in0A8TypeTest5horsey4Barn5HorseV_tF11LocalStructL_VD"
+  // CHECK-DAG: DICompositeType(tag: DW_TAG_structure_type, {{.*}}identifier: "$s32local_type_originally_defined_in0A8TypeTest5horsey4Barn5HorseV_tF11LocalStructL_VD"
 }

 public func localTypeAliasTest() -> Horse {
@@ -40,7 +40,7 @@ public func localTypeAliasTest() -> Horse {
  let info = UnsafeMutablePointer<B>.allocate(capacity: 1)
  _ = info
  return Horse()
-  // CHECK: DIDerivedType(tag: DW_TAG_typedef, name: "$s32local_type_originally_defined_in0A13TypeAliasTest4Barn5HorseVyF1BL_aD"
+  // CHECK-DAG: DIDerivedType(tag: DW_TAG_typedef, name: "$s32local_type_originally_defined_in0A13TypeAliasTest4Barn5HorseVyF1BL_aD"
 }

 public func localTypeAliasTestGeneric<T: Cow>(cow: T) {
--- a/test/DebugInfo/protocol-extension.swift
+++ b/test/DebugInfo/protocol-extension.swift
@@ -15,6 +15,5 @@ public extension P {
  }
 }

-// CHECK: ![[SELFMETA]] = !DILocalVariable(name: "$\CF\84_0_0",
-// CHECK-SAME: type: ![[SELFTY:[0-9]+]], flags: DIFlagArtificial)
-// CHECK: ![[SELFTY]] = !DIDerivedType(tag: DW_TAG_typedef, name: "Self"
+// CHECK-DAG: ![[SELFMETA]] = !DILocalVariable(name: "$\CF\84_0_0", {{.*}}type: ![[SELFTY:[0-9]+]], flags: DIFlagArtificial)
+// CHECK-DAG: ![[SELFTY]] = !DIDerivedType(tag: DW_TAG_typedef, name: "Self"
--- a/test/DebugInfo/test-foundation.swift
+++ b/test/DebugInfo/test-foundation.swift
@@ -18,7 +18,7 @@ class MyObject : NSObject {
  // LOC-CHECK: ret
  @objc var MyArr = NSArray()
  // IMPORT-CHECK: filename: "{{.*}}test-foundation.swift"
-  // IMPORT-CHECK-DAG: [[FOUNDATION:[0-9]+]] = !DIModule({{.*}} name: "Foundation",{{.*}} includePath: {{.*}}Foundation.framework
+  // IMPORT-CHECK-DAG: [[FOUNDATION:[0-9]+]] = !DIModule({{.*}} name: "Foundation",{{.*}} includePath: {{.*}}Foundation.framework"
  // IMPORT-CHECK-DAG: [[OVERLAY:[0-9]+]] = !DIModule({{.*}} name: "Foundation",{{.*}} includePath: {{.*}}Foundation.swiftmodule
  // IMPORT-CHECK-DAG: !DICompositeType(tag: DW_TAG_structure_type, name: "NSArray", scope: ![[NSARRAY:[0-9]+]]
  //  IMPORT-CHECK-DAG: ![[NSARRAY]] = !DIModule(scope: ![[FOUNDATION:[0-9]+]], name: "NSArray"
--- a/test/DebugInfo/typearg.swift
+++ b/test/DebugInfo/typearg.swift
@@ -9,12 +9,9 @@ class AClass : AProtocol {

 // CHECK: define hidden {{.*}}void @{{.*}}aFunction
 // CHECK:  #dbg_declare(ptr %{{.*}}, ![[TYPEARG:.*]], !DIExpression(),
-// CHECK: ![[TYPEARG]] = !DILocalVariable(name: "$\CF\84_0_0"
-// CHECK-SAME:                            type: ![[SWIFTMETATYPE:[^,)]+]]
-// CHECK-SAME:                            flags: DIFlagArtificial
-// CHECK: ![[SWIFTMETATYPE]] = !DIDerivedType(tag: DW_TAG_typedef, name: "T",
-// CHECK-SAME:                                baseType: ![[VOIDPTR:[0-9]+]]
-// CHECK: ![[VOIDPTR]] = !DIDerivedType(tag: DW_TAG_pointer_type, name: "$sBpD", baseType: null
+// CHECK-DAG: ![[TYPEARG]] = !DILocalVariable(name: "$\CF\84_0_0"{{.*}}type: ![[SWIFTMETATYPE:[^,)]+]]{{.*}}flags: DIFlagArtificial
+// CHECK-DAG: ![[SWIFTMETATYPE]] = !DIDerivedType(tag: DW_TAG_typedef, name: "T",{{.*}}baseType: ![[VOIDPTR:[0-9]+]]
+// CHECK-DAG: ![[VOIDPTR]] = !DIDerivedType(tag: DW_TAG_pointer_type, name: "$sBpD", baseType: null
 func aFunction<T : AProtocol>(_ x: T) {
    print("I am in aFunction: \(x.f())")
 }
--- a/test/DebugInfo/value-generics.swift
+++ b/test/DebugInfo/value-generics.swift
@@ -10,7 +10,7 @@ struct Slab<let N: Int, Element: ~Copyable>: ~Copyable {

 extension Slab: Copyable where Element: Copyable {}

-// CHECK-DAG: !DICompositeType({{.*}}name: "Builtin.FixedArray", {{.*}}identifier: "$sxq_BVD"
+// CHECK-DAG: !DICompositeType({{.*}}name: "$sxq_BVD"
 func genericBA<let N: Int, Element>(_: Builtin.FixedArray<N, Element>) {}

 // CHECK-DAG: !DICompositeType({{.*}}name: "$s4main4SlabVyxq_GD"
@@ -24,5 +24,5 @@ func concreteBA(_: Builtin.FixedArray<4, Int>) {}
 // CHECK-DAG: ![[COUNT_PARAM]] = !DITemplateTypeParameter(type: ![[COUNT_TYPE:.*]])
 // CHECK-DAG: ![[COUNT_TYPE]] = !DICompositeType({{.*}}name: "$s$1_D"
 // CHECK-DAG: ![[ELEMENT_PARAM]] = !DITemplateTypeParameter(type: ![[ELEMENT_TYPE:.*]])
-// CHECK-DAG: ![[ELEMENT_TYPE]] = !DICompositeType({{.*}}name: "$sSiD"
+// CHECK-DAG: ![[ELEMENT_TYPE]] = !DICompositeType({{.*}}identifier: "$sSiD"
 func concreteV(_: Slab<2, Int>) {}