Revert "[Serialization] Support load lazy specialization lazily"

This reverts commit b5bd192.
It brokes multiple llvm bots including clang-x64-windows-msvc

Author: zeroomega

clang/include/clang/AST/DeclTemplate.h

@@ -735,7 +735,6 @@ class RedeclarableTemplateDecl : public TemplateDecl,
   }
 
   void anchor() override;
-
 protected:
   template <typename EntryType> struct SpecEntryTraits {
     using DeclType = EntryType;
@@ -776,22 +775,13 @@ class RedeclarableTemplateDecl : public TemplateDecl,
     return SpecIterator<EntryType>(isEnd ? Specs.end() : Specs.begin());
   }
 
-  void loadLazySpecializationsImpl(bool OnlyPartial = false) const;
-
-  bool loadLazySpecializationsImpl(llvm::ArrayRef<TemplateArgument> Args,
-                                   TemplateParameterList *TPL = nullptr) const;
+  void loadLazySpecializationsImpl() const;
 
   template <class EntryType, typename ...ProfileArguments>
   typename SpecEntryTraits<EntryType>::DeclType*
   findSpecializationImpl(llvm::FoldingSetVector<EntryType> &Specs,
                          void *&InsertPos, ProfileArguments &&...ProfileArgs);
 
-  template <class EntryType, typename... ProfileArguments>
-  typename SpecEntryTraits<EntryType>::DeclType *
-  findSpecializationLocally(llvm::FoldingSetVector<EntryType> &Specs,
-                            void *&InsertPos,
-                            ProfileArguments &&...ProfileArgs);
-
   template <class Derived, class EntryType>
   void addSpecializationImpl(llvm::FoldingSetVector<EntryType> &Specs,
                              EntryType *Entry, void *InsertPos);
@@ -806,6 +796,13 @@ class RedeclarableTemplateDecl : public TemplateDecl,
     /// was explicitly specialized.
     llvm::PointerIntPair<RedeclarableTemplateDecl *, 1, bool>
         InstantiatedFromMember;
+
+    /// If non-null, points to an array of specializations (including
+    /// partial specializations) known only by their external declaration IDs.
+    ///
+    /// The first value in the array is the number of specializations/partial
+    /// specializations that follow.
+    GlobalDeclID *LazySpecializations = nullptr;
   };
 
   /// Pointer to the common data shared by all declarations of this
@@ -2286,7 +2283,7 @@ class ClassTemplateDecl : public RedeclarableTemplateDecl {
   friend class TemplateDeclInstantiator;
 
   /// Load any lazily-loaded specializations from the external source.
-  void LoadLazySpecializations(bool OnlyPartial = false) const;
+  void LoadLazySpecializations() const;
 
   /// Get the underlying class declarations of the template.
   CXXRecordDecl *getTemplatedDecl() const {
@@ -3036,7 +3033,7 @@ class VarTemplateDecl : public RedeclarableTemplateDecl {
   friend class ASTDeclWriter;
 
   /// Load any lazily-loaded specializations from the external source.
-  void LoadLazySpecializations(bool OnlyPartial = false) const;
+  void LoadLazySpecializations() const;
 
   /// Get the underlying variable declarations of the template.
   VarDecl *getTemplatedDecl() const {

clang/include/clang/AST/ExternalASTSource.h

@@ -152,21 +152,6 @@ class ExternalASTSource : public RefCountedBase<ExternalASTSource> {
   virtual bool
   FindExternalVisibleDeclsByName(const DeclContext *DC, DeclarationName Name);
 
-  /// Load all the external specializations for the Decl \param D if \param
-  /// OnlyPartial is false. Otherwise, load all the external **partial**
-  /// specializations for the \param D.
-  ///
-  /// Return true if any new specializations get loaded. Return false otherwise.
-  virtual bool LoadExternalSpecializations(const Decl *D, bool OnlyPartial);
-
-  /// Load all the specializations for the Decl \param D with the same template
-  /// args specified by \param TemplateArgs.
-  ///
-  /// Return true if any new specializations get loaded. Return false otherwise.
-  virtual bool
-  LoadExternalSpecializations(const Decl *D,
-                              ArrayRef<TemplateArgument> TemplateArgs);
-
   /// Ensures that the table of all visible declarations inside this
   /// context is up to date.
   ///

clang/include/clang/Sema/MultiplexExternalSemaSource.h

@@ -97,12 +97,6 @@ class MultiplexExternalSemaSource : public ExternalSemaSource {
   bool FindExternalVisibleDeclsByName(const DeclContext *DC,
                                       DeclarationName Name) override;
 
-  bool LoadExternalSpecializations(const Decl *D, bool OnlyPartial) override;
-
-  bool
-  LoadExternalSpecializations(const Decl *D,
-                              ArrayRef<TemplateArgument> TemplateArgs) override;
-
   /// Ensures that the table of all visible declarations inside this
   /// context is up to date.
   void completeVisibleDeclsMap(const DeclContext *DC) override;

clang/include/clang/Serialization/ASTBitCodes.h

@@ -733,13 +733,6 @@ enum ASTRecordTypes {
   /// Record code for Sema's vector of functions/blocks with effects to
   /// be verified.
   DECLS_WITH_EFFECTS_TO_VERIFY = 72,
-
-  /// Record code for updated specialization
-  UPDATE_SPECIALIZATION = 73,
-
-  CXX_ADDED_TEMPLATE_SPECIALIZATION = 74,
-
-  CXX_ADDED_TEMPLATE_PARTIAL_SPECIALIZATION = 75,
 };
 
 /// Record types used within a source manager block.
@@ -1509,12 +1502,6 @@ enum DeclCode {
   /// An ImplicitConceptSpecializationDecl record.
   DECL_IMPLICIT_CONCEPT_SPECIALIZATION,
 
-  // A decls specilization record.
-  DECL_SPECIALIZATIONS,
-
-  // A decls specilization record.
-  DECL_PARTIAL_SPECIALIZATIONS,
-
   DECL_LAST = DECL_IMPLICIT_CONCEPT_SPECIALIZATION
 };
 

clang/include/clang/Serialization/ASTReader.h

@@ -354,9 +354,6 @@ class ASTIdentifierLookupTrait;
 /// The on-disk hash table(s) used for DeclContext name lookup.
 struct DeclContextLookupTable;
 
-/// The on-disk hash table(s) used for specialization decls.
-struct LazySpecializationInfoLookupTable;
-
 } // namespace reader
 
 } // namespace serialization
@@ -635,40 +632,20 @@ class ASTReader
   llvm::DenseMap<const DeclContext *,
                  serialization::reader::DeclContextLookupTable> Lookups;
 
-  using SpecLookupTableTy =
-      llvm::DenseMap<const Decl *,
-                     serialization::reader::LazySpecializationInfoLookupTable>;
-  /// Map from decls to specialized decls.
-  SpecLookupTableTy SpecializationsLookups;
-  /// Split partial specialization from specialization to speed up lookups.
-  SpecLookupTableTy PartialSpecializationsLookups;
-
-  bool LoadExternalSpecializationsImpl(SpecLookupTableTy &SpecLookups,
-                                       const Decl *D);
-  bool LoadExternalSpecializationsImpl(SpecLookupTableTy &SpecLookups,
-                                       const Decl *D,
-                                       ArrayRef<TemplateArgument> TemplateArgs);
-
   // Updates for visible decls can occur for other contexts than just the
   // TU, and when we read those update records, the actual context may not
   // be available yet, so have this pending map using the ID as a key. It
-  // will be realized when the data is actually loaded.
-  struct UpdateData {
+  // will be realized when the context is actually loaded.
+  struct PendingVisibleUpdate {
     ModuleFile *Mod;
     const unsigned char *Data;
   };
-  using DeclContextVisibleUpdates = SmallVector<UpdateData, 1>;
+  using DeclContextVisibleUpdates = SmallVector<PendingVisibleUpdate, 1>;
 
   /// Updates to the visible declarations of declaration contexts that
   /// haven't been loaded yet.
   llvm::DenseMap<GlobalDeclID, DeclContextVisibleUpdates> PendingVisibleUpdates;
 
-  using SpecializationsUpdate = SmallVector<UpdateData, 1>;
-  using SpecializationsUpdateMap =
-      llvm::DenseMap<GlobalDeclID, SpecializationsUpdate>;
-  SpecializationsUpdateMap PendingSpecializationsUpdates;
-  SpecializationsUpdateMap PendingPartialSpecializationsUpdates;
-
   /// The set of C++ or Objective-C classes that have forward
   /// declarations that have not yet been linked to their definitions.
   llvm::SmallPtrSet<Decl *, 4> PendingDefinitions;
@@ -701,11 +678,6 @@ class ASTReader
                                      llvm::BitstreamCursor &Cursor,
                                      uint64_t Offset, GlobalDeclID ID);
 
-  bool ReadSpecializations(ModuleFile &M, llvm::BitstreamCursor &Cursor,
-                           uint64_t Offset, Decl *D, bool IsPartial);
-  void AddSpecializations(const Decl *D, const unsigned char *Data,
-                          ModuleFile &M, bool IsPartial);
-
   /// A vector containing identifiers that have already been
   /// loaded.
   ///
@@ -1447,14 +1419,6 @@ class ASTReader
   const serialization::reader::DeclContextLookupTable *
   getLoadedLookupTables(DeclContext *Primary) const;
 
-  /// Get the loaded specializations lookup tables for \p D,
-  /// if any.
-  serialization::reader::LazySpecializationInfoLookupTable *
-  getLoadedSpecializationsLookupTables(const Decl *D, bool IsPartial);
-
-  /// If we have any unloaded specialization for \p D
-  bool haveUnloadedSpecializations(const Decl *D) const;
-
 private:
   struct ImportedModule {
     ModuleFile *Mod;
@@ -2112,12 +2076,6 @@ class ASTReader
                                       unsigned BlockID,
                                       uint64_t *StartOfBlockOffset = nullptr);
 
-  bool LoadExternalSpecializations(const Decl *D, bool OnlyPartial) override;
-
-  bool
-  LoadExternalSpecializations(const Decl *D,
-                              ArrayRef<TemplateArgument> TemplateArgs) override;
-
   /// Finds all the visible declarations with a given name.
   /// The current implementation of this method just loads the entire
   /// lookup table as unmaterialized references.

clang/include/clang/Serialization/ASTWriter.h

@@ -423,13 +423,6 @@ class ASTWriter : public ASTDeserializationListener,
   /// Only meaningful for reduced BMI.
   DeclUpdateMap DeclUpdatesFromGMF;
 
-  /// Mapping from decl templates and its new specialization in the
-  /// current TU.
-  using SpecializationUpdateMap =
-      llvm::MapVector<const NamedDecl *, SmallVector<const Decl *>>;
-  SpecializationUpdateMap SpecializationsUpdates;
-  SpecializationUpdateMap PartialSpecializationsUpdates;
-
   using FirstLatestDeclMap = llvm::DenseMap<Decl *, Decl *>;
 
   /// Map of first declarations from a chained PCH that point to the
@@ -582,12 +575,6 @@ class ASTWriter : public ASTDeserializationListener,
 
   bool isLookupResultExternal(StoredDeclsList &Result, DeclContext *DC);
 
-  void GenerateSpecializationInfoLookupTable(
-      const NamedDecl *D, llvm::SmallVectorImpl<const Decl *> &Specializations,
-      llvm::SmallVectorImpl<char> &LookupTable, bool IsPartial);
-  uint64_t WriteSpecializationInfoLookupTable(
-      const NamedDecl *D, llvm::SmallVectorImpl<const Decl *> &Specializations,
-      bool IsPartial);
   void GenerateNameLookupTable(ASTContext &Context, const DeclContext *DC,
                                llvm::SmallVectorImpl<char> &LookupTable);
   uint64_t WriteDeclContextLexicalBlock(ASTContext &Context,
@@ -603,7 +590,6 @@ class ASTWriter : public ASTDeserializationListener,
   void WriteDeclAndTypes(ASTContext &Context);
   void PrepareWritingSpecialDecls(Sema &SemaRef);
   void WriteSpecialDeclRecords(Sema &SemaRef);
-  void WriteSpecializationsUpdates(bool IsPartial);
   void WriteDeclUpdatesBlocks(ASTContext &Context,
                               RecordDataImpl &OffsetsRecord);
   void WriteDeclContextVisibleUpdate(ASTContext &Context,
@@ -633,9 +619,6 @@ class ASTWriter : public ASTDeserializationListener,
   unsigned DeclEnumAbbrev = 0;
   unsigned DeclObjCIvarAbbrev = 0;
   unsigned DeclCXXMethodAbbrev = 0;
-  unsigned DeclSpecializationsAbbrev = 0;
-  unsigned DeclPartialSpecializationsAbbrev = 0;
-
   unsigned DeclDependentNonTemplateCXXMethodAbbrev = 0;
   unsigned DeclTemplateCXXMethodAbbrev = 0;
   unsigned DeclMemberSpecializedCXXMethodAbbrev = 0;