[modules] Remove CXX_CTOR_INITIALIZERS_OFFSETS table. Instead of storing an ID

of a table entry in the corresponding decl, store an offset from the current
record to the relevant CXX_CTOR_INITIALIZERS record. This results in fewer
indirections and a minor .pcm file size reduction.

llvm-svn: 266254

5 files changed, 43 insertions, 113 deletions

diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index df1418649d6..947df5e4448 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -3064,17 +3064,6 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       break;
     }
 
-    case CXX_CTOR_INITIALIZERS_OFFSETS: {
-      if (F.LocalNumCXXCtorInitializers != 0) {
-        Error("duplicate CXX_CTOR_INITIALIZERS_OFFSETS record in AST file");
-        return Failure;
-      }
-
-      F.LocalNumCXXCtorInitializers = Record[0];
-      F.CXXCtorInitializersOffsets = (const uint32_t *)Blob.data();
-      break;
-    }
-
     case DIAG_PRAGMA_MAPPINGS:
       if (F.PragmaDiagMappings.empty())
         F.PragmaDiagMappings.swap(Record);
@@ -6303,18 +6292,6 @@ void ASTReader::CompleteRedeclChain(const Decl *D) {
   }
 }
 
-uint64_t ASTReader::ReadCXXCtorInitializersRef(ModuleFile &M,
-                                               const RecordData &Record,
-                                               unsigned &Idx) {
-  if (Idx >= Record.size() || Record[Idx] > M.LocalNumCXXCtorInitializers) {
-    Error("malformed AST file: missing C++ ctor initializers");
-    return 0;
-  }
-
-  unsigned LocalID = Record[Idx++];
-  return getGlobalBitOffset(M, M.CXXCtorInitializersOffsets[LocalID - 1]);
-}
-
 CXXCtorInitializer **
 ASTReader::GetExternalCXXCtorInitializers(uint64_t Offset) {
   RecordLocation Loc = getLocalBitOffset(Offset);
diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index efb7793ef61..4316be1d006 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -59,6 +59,11 @@ namespace clang {
       return LocalOffset ? Offset - LocalOffset : 0;
     }
 
+    uint64_t ReadGlobalOffset(ModuleFile &F, const RecordData &R, unsigned &I) {
+      uint64_t Local = ReadLocalOffset(R, I);
+      return Local ? Reader.getGlobalBitOffset(F, Local) : 0;
+    }
+
     SourceLocation ReadSourceLocation(const RecordData &R, unsigned &I) {
       return Reader.ReadSourceLocation(F, R, I);
     }
@@ -472,8 +477,7 @@ void ASTDeclReader::Visit(Decl *D) {
       if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
         CD->NumCtorInitializers = Record[Idx++];
         if (CD->NumCtorInitializers)
-          CD->CtorInitializers =
-              Reader.ReadCXXCtorInitializersRef(F, Record, Idx);
+          CD->CtorInitializers = ReadGlobalOffset(F, Record, Idx);
       }
       Reader.PendingBodies[FD] = GetCurrentCursorOffset();
       HasPendingBody = true;
@@ -1137,7 +1141,7 @@ void ASTDeclReader::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
   D->setHasDestructors(Record[Idx++]);
   D->NumIvarInitializers = Record[Idx++];
   if (D->NumIvarInitializers)
-    D->IvarInitializers = Reader.ReadCXXCtorInitializersRef(F, Record, Idx);
+    D->IvarInitializers = ReadGlobalOffset(F, Record, Idx);
 }
 
 void ASTDeclReader::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
@@ -3745,8 +3749,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
       if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
         CD->NumCtorInitializers = Record[Idx++];
         if (CD->NumCtorInitializers)
-          CD->CtorInitializers =
-              Reader.ReadCXXCtorInitializersRef(F, Record, Idx);
+          CD->CtorInitializers = ReadGlobalOffset(F, Record, Idx);
       }
       // Store the offset of the body so we can lazily load it later.
       Reader.PendingBodies[FD] = GetCurrentCursorOffset();
diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index c644a39f426..0f9677715ff 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -983,7 +983,6 @@ void ASTWriter::WriteBlockInfoBlock() {
   RECORD(MSSTRUCT_PRAGMA_OPTIONS);
   RECORD(POINTERS_TO_MEMBERS_PRAGMA_OPTIONS);
   RECORD(UNUSED_LOCAL_TYPEDEF_NAME_CANDIDATES);
-  RECORD(CXX_CTOR_INITIALIZERS_OFFSETS);
   RECORD(DELETE_EXPRS_TO_ANALYZE);
 
   // SourceManager Block.
@@ -2725,26 +2724,6 @@ void ASTWriter::WritePragmaDiagnosticMappings(const DiagnosticsEngine &Diag,
     Stream.EmitRecord(DIAG_PRAGMA_MAPPINGS, Record);
 }
 
-void ASTWriter::WriteCXXCtorInitializersOffsets() {
-  if (CXXCtorInitializersOffsets.empty())
-    return;
-
-  // Create a blob abbreviation for the C++ ctor initializer offsets.
-  using namespace llvm;
-
-  auto *Abbrev = new BitCodeAbbrev();
-  Abbrev->Add(BitCodeAbbrevOp(CXX_CTOR_INITIALIZERS_OFFSETS));
-  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // size
-  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
-  unsigned CtorInitializersOffsetAbbrev = Stream.EmitAbbrev(Abbrev);
-
-  // Write the base specifier offsets table.
-  RecordData::value_type Record[] = {CXX_CTOR_INITIALIZERS_OFFSETS,
-                                     CXXCtorInitializersOffsets.size()};
-  Stream.EmitRecordWithBlob(CtorInitializersOffsetAbbrev, Record,
-                            bytes(CXXCtorInitializersOffsets));
-}
-
 void ASTWriter::WriteCXXBaseSpecifiersOffsets() {
   if (CXXBaseSpecifiersOffsets.empty())
     return;
@@ -4116,7 +4095,7 @@ ASTWriter::ASTWriter(
       FirstSelectorID(NUM_PREDEF_SELECTOR_IDS), NextSelectorID(FirstSelectorID),
       NumStatements(0), NumMacros(0),
       NumLexicalDeclContexts(0), NumVisibleDeclContexts(0),
-      NextCXXBaseSpecifiersID(1), NextCXXCtorInitializersID(1),
+      NextCXXBaseSpecifiersID(1),
       TypeExtQualAbbrev(0), TypeFunctionProtoAbbrev(0), DeclParmVarAbbrev(0),
       DeclContextLexicalAbbrev(0), DeclContextVisibleLookupAbbrev(0),
       UpdateVisibleAbbrev(0), DeclRecordAbbrev(0), DeclTypedefAbbrev(0),
@@ -4518,7 +4497,6 @@ uint64_t ASTWriter::WriteASTCore(Sema &SemaRef, StringRef isysroot,
   if (!DeclUpdatesOffsetsRecord.empty())
     Stream.EmitRecord(DECL_UPDATE_OFFSETS, DeclUpdatesOffsetsRecord);
   WriteCXXBaseSpecifiersOffsets();
-  WriteCXXCtorInitializersOffsets();
   WriteFileDeclIDsMap();
   WriteSourceManagerBlock(Context.getSourceManager(), PP);
   WriteComments();
@@ -4899,14 +4877,6 @@ void ASTWriter::AddCXXTemporary(const CXXTemporary *Temp, RecordDataImpl &Record
   AddDeclRef(Temp->getDestructor(), Record);
 }
 
-void ASTWriter::AddCXXCtorInitializersRef(ArrayRef<CXXCtorInitializer *> Inits,
-                                          RecordDataImpl &Record) {
-  assert(!Inits.empty() && "Empty ctor initializer sets are not recorded");
-  CXXCtorInitializersToWrite.push_back(
-      QueuedCXXCtorInitializers(NextCXXCtorInitializersID, Inits));
-  Record.push_back(NextCXXCtorInitializersID++);
-}
-
 void ASTWriter::AddCXXBaseSpecifiersRef(CXXBaseSpecifier const *Bases,
                                         CXXBaseSpecifier const *BasesEnd,
                                         RecordDataImpl &Record) {
@@ -5488,69 +5458,50 @@ void ASTWriter::FlushCXXBaseSpecifiers() {
 }
 
 // FIXME: Move this out of the main ASTRecordWriter interface.
-void ASTRecordWriter::AddCXXCtorInitializers(
-    const CXXCtorInitializer *const *CtorInitializers,
-    unsigned NumCtorInitializers) {
-  Record->push_back(NumCtorInitializers);
-  for (unsigned i=0; i != NumCtorInitializers; ++i) {
-    const CXXCtorInitializer *Init = CtorInitializers[i];
-
+static uint64_t
+EmitCXXCtorInitializers(ASTWriter &W,
+                        ArrayRef<CXXCtorInitializer *> CtorInits) {
+  ASTWriter::RecordData Record;
+  ASTRecordWriter Writer(W, Record);
+  Writer.push_back(CtorInits.size());
+
+  for (auto *Init : CtorInits) {
     if (Init->isBaseInitializer()) {
-      Record->push_back(CTOR_INITIALIZER_BASE);
-      AddTypeSourceInfo(Init->getTypeSourceInfo());
-      Record->push_back(Init->isBaseVirtual());
+      Writer.push_back(CTOR_INITIALIZER_BASE);
+      Writer.AddTypeSourceInfo(Init->getTypeSourceInfo());
+      Writer.push_back(Init->isBaseVirtual());
     } else if (Init->isDelegatingInitializer()) {
-      Record->push_back(CTOR_INITIALIZER_DELEGATING);
-      AddTypeSourceInfo(Init->getTypeSourceInfo());
+      Writer.push_back(CTOR_INITIALIZER_DELEGATING);
+      Writer.AddTypeSourceInfo(Init->getTypeSourceInfo());
     } else if (Init->isMemberInitializer()){
-      Record->push_back(CTOR_INITIALIZER_MEMBER);
-      AddDeclRef(Init->getMember());
+      Writer.push_back(CTOR_INITIALIZER_MEMBER);
+      Writer.AddDeclRef(Init->getMember());
     } else {
-      Record->push_back(CTOR_INITIALIZER_INDIRECT_MEMBER);
-      AddDeclRef(Init->getIndirectMember());
+      Writer.push_back(CTOR_INITIALIZER_INDIRECT_MEMBER);
+      Writer.AddDeclRef(Init->getIndirectMember());
     }
 
-    AddSourceLocation(Init->getMemberLocation());
-    AddStmt(Init->getInit());
-    AddSourceLocation(Init->getLParenLoc());
-    AddSourceLocation(Init->getRParenLoc());
-    Record->push_back(Init->isWritten());
+    Writer.AddSourceLocation(Init->getMemberLocation());
+    Writer.AddStmt(Init->getInit());
+    Writer.AddSourceLocation(Init->getLParenLoc());
+    Writer.AddSourceLocation(Init->getRParenLoc());
+    Writer.push_back(Init->isWritten());
     if (Init->isWritten()) {
-      Record->push_back(Init->getSourceOrder());
+      Writer.push_back(Init->getSourceOrder());
     } else {
-      Record->push_back(Init->getNumArrayIndices());
-      for (unsigned i=0, e=Init->getNumArrayIndices(); i != e; ++i)
-        AddDeclRef(Init->getArrayIndex(i));
+      Writer.push_back(Init->getNumArrayIndices());
+      for (auto *VD : Init->getArrayIndices())
+        Writer.AddDeclRef(VD);
     }
   }
-}
-
-void ASTWriter::FlushCXXCtorInitializers() {
-  RecordData Record;
-
-  unsigned N = CXXCtorInitializersToWrite.size();
-  (void)N; // Silence unused warning in non-assert builds.
-  for (auto &Init : CXXCtorInitializersToWrite) {
-    Record.clear();
-
-    ASTRecordWriter Writer(*this, Record);
-    Writer.AddCXXCtorInitializers(Init.Inits.data(), Init.Inits.size());
-    uint64_t Offset = Writer.Emit(serialization::DECL_CXX_CTOR_INITIALIZERS);
 
-    // Record the offset of this mem-initializer list.
-    unsigned Index = Init.ID - 1;
-    if (Index == CXXCtorInitializersOffsets.size())
-      CXXCtorInitializersOffsets.push_back(Offset);
-    else {
-      if (Index > CXXCtorInitializersOffsets.size())
-        CXXCtorInitializersOffsets.resize(Index + 1);
-      CXXCtorInitializersOffsets[Index] = Offset;
-    }
-  }
+  return Writer.Emit(serialization::DECL_CXX_CTOR_INITIALIZERS);
+}
 
-  assert(N == CXXCtorInitializersToWrite.size() &&
-         "added more ctor initializers while writing ctor initializers");
-  CXXCtorInitializersToWrite.clear();
+// FIXME: Move this out of the main ASTRecordWriter interface.
+void ASTRecordWriter::AddCXXCtorInitializers(
+    ArrayRef<CXXCtorInitializer *> CtorInits) {
+  AddOffset(EmitCXXCtorInitializers(*Writer, CtorInits));
 }
 
 void ASTRecordWriter::AddCXXDefinitionData(const CXXRecordDecl *D) {
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index bfce2459038..94a593fe486 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -823,7 +823,7 @@ void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
   Record.push_back(D->hasDestructors());
   Record.push_back(D->NumIvarInitializers);
   if (D->NumIvarInitializers)
-    Record.AddCXXCtorInitializersRef(
+    Record.AddCXXCtorInitializers(
         llvm::makeArrayRef(D->init_begin(), D->init_end()));
   Code = serialization::DECL_OBJC_IMPLEMENTATION;
 }
@@ -2177,7 +2177,7 @@ void ASTRecordWriter::AddFunctionDefinition(const FunctionDecl *FD) {
   if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
     Record->push_back(CD->getNumCtorInitializers());
     if (CD->getNumCtorInitializers())
-      AddCXXCtorInitializersRef(
+      AddCXXCtorInitializers(
           llvm::makeArrayRef(CD->init_begin(), CD->init_end()));
   }
   AddStmt(FD->getBody());
diff --git a/clang/lib/Serialization/Module.cpp b/clang/lib/Serialization/Module.cpp
index ca033b469b5..872a447429f 100644
--- a/clang/lib/Serialization/Module.cpp
+++ b/clang/lib/Serialization/Module.cpp
@@ -38,7 +38,6 @@ ModuleFile::ModuleFile(ModuleKind Kind, unsigned Generation)
     SelectorLookupTableData(nullptr), SelectorLookupTable(nullptr),
     LocalNumDecls(0), DeclOffsets(nullptr), BaseDeclID(0),
     LocalNumCXXBaseSpecifiers(0), CXXBaseSpecifiersOffsets(nullptr),
-    LocalNumCXXCtorInitializers(0), CXXCtorInitializersOffsets(nullptr),
     FileSortedDecls(nullptr), NumFileSortedDecls(0),
     ObjCCategoriesMap(nullptr), LocalNumObjCCategoriesInMap(0),
     LocalNumTypes(0), TypeOffsets(nullptr), BaseTypeIndex(0)