Read/write declaration attributes from/to PCH properly. Embed them in the declaration block instead of trying to create another block.

The new block was messing with the assumption that after decls block comes the stmts block.
Fixes http://llvm.org/PR8406

llvm-svn: 116737

clang/include/clang/Serialization/ASTBitCodes.h

@@ -579,10 +579,8 @@ namespace clang {
     /// constant describes a record for a specific declaration class
     /// in the AST.
     enum DeclCode {
-      /// \brief Attributes attached to a declaration.
-      DECL_ATTR = 50,
       /// \brief A TranslationUnitDecl record.
-      DECL_TRANSLATION_UNIT,
+      DECL_TRANSLATION_UNIT = 50,
       /// \brief A TypedefDecl record.
       DECL_TYPEDEF,
       /// \brief An EnumDecl record.

clang/include/clang/Serialization/ASTReader.h

@@ -1095,7 +1095,8 @@ public:
   CXXTemporary *ReadCXXTemporary(const RecordData &Record, unsigned &Idx);
       
   /// \brief Reads attributes from the current stream position.
-  void ReadAttributes(PerFileData &F, AttrVec &Attrs);
+  void ReadAttributes(PerFileData &F, AttrVec &Attrs,
+                      const RecordData &Record, unsigned &Idx);
 
   /// \brief Reads a statement.
   Stmt *ReadStmt(PerFileData &F);

clang/include/clang/Serialization/ASTWriter.h

@@ -279,7 +279,7 @@ private:
   void WriteSelectors(Sema &SemaRef);
   void WriteReferencedSelectorsPool(Sema &SemaRef);
   void WriteIdentifierTable(Preprocessor &PP);
-  void WriteAttributeRecord(const AttrVec &Attrs);
+  void WriteAttributes(const AttrVec &Attrs, RecordData &Record);
   void WriteDeclUpdateBlock();
   void WriteDeclContextVisibleUpdate(const DeclContext *DC);
   void WriteAdditionalTemplateSpecializations();

clang/lib/Serialization/ASTReaderDecl.cpp

@@ -172,9 +172,9 @@ void ASTDeclReader::VisitDecl(Decl *D) {
                      cast_or_null<DeclContext>(Reader.GetDecl(Record[Idx++])));
   D->setLocation(ReadSourceLocation(Record, Idx));
   D->setInvalidDecl(Record[Idx++]);
-  if (Record[Idx++]) {
+  if (Record[Idx++]) { // hasAttrs
     AttrVec Attrs;
-    Reader.ReadAttributes(F, Attrs);
+    Reader.ReadAttributes(F, Attrs, Record, Idx);
     D->setAttrs(Attrs);
   }
   D->setImplicit(Record[Idx++]);
@@ -1200,19 +1200,9 @@ void ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
 //===----------------------------------------------------------------------===//
 
 /// \brief Reads attributes from the current stream position.
-void ASTReader::ReadAttributes(PerFileData &F, AttrVec &Attrs) {
-  llvm::BitstreamCursor &DeclsCursor = F.DeclsCursor;
-  unsigned Code = DeclsCursor.ReadCode();
-  assert(Code == llvm::bitc::UNABBREV_RECORD &&
-         "Expected unabbreviated record"); (void)Code;
-
-  RecordData Record;
-  unsigned Idx = 0;
-  unsigned RecCode = DeclsCursor.ReadRecord(Code, Record);
-  assert(RecCode == DECL_ATTR && "Expected attribute record");
-  (void)RecCode;
-
-  while (Idx < Record.size()) {
+void ASTReader::ReadAttributes(PerFileData &F, AttrVec &Attrs,
+                               const RecordData &Record, unsigned &Idx) {
+  for (unsigned i = 0, e = Record[Idx++]; i != e; ++i) {
     Attr *New = 0;
     attr::Kind Kind = (attr::Kind)Record[Idx++];
     SourceLocation Loc = ReadSourceLocation(F, Record, Idx);
@@ -1299,7 +1289,6 @@ Decl *ASTReader::ReadDeclRecord(unsigned Index, DeclID ID) {
 
   Decl *D = 0;
   switch ((DeclCode)DeclsCursor.ReadRecord(Code, Record)) {
-  case DECL_ATTR:
   case DECL_CONTEXT_LEXICAL:
   case DECL_CONTEXT_VISIBLE:
     assert(false && "Record cannot be de-serialized with ReadDeclRecord");

clang/lib/Serialization/ASTWriter.cpp

@@ -684,7 +684,6 @@ void ASTWriter::WriteBlockInfoBlock() {
   RECORD(TYPE_OBJC_INTERFACE);
   RECORD(TYPE_OBJC_OBJECT);
   RECORD(TYPE_OBJC_OBJECT_POINTER);
-  RECORD(DECL_ATTR);
   RECORD(DECL_TRANSLATION_UNIT);
   RECORD(DECL_TYPEDEF);
   RECORD(DECL_ENUM);
@@ -2168,8 +2167,8 @@ void ASTWriter::WriteAdditionalTemplateSpecializations() {
 //===----------------------------------------------------------------------===//
 
 /// \brief Write a record containing the given attributes.
-void ASTWriter::WriteAttributeRecord(const AttrVec &Attrs) {
-  RecordData Record;
+void ASTWriter::WriteAttributes(const AttrVec &Attrs, RecordData &Record) {
+  Record.push_back(Attrs.size());
   for (AttrVec::const_iterator i = Attrs.begin(), e = Attrs.end(); i != e; ++i){
     const Attr * A = *i;
     Record.push_back(A->getKind()); // FIXME: stable encoding, target attrs
@@ -2179,8 +2178,6 @@ void ASTWriter::WriteAttributeRecord(const AttrVec &Attrs) {
 #include "clang/Serialization/AttrPCHWrite.inc"
 
   }
-
-  Stream.EmitRecord(DECL_ATTR, Record);
 }
 
 void ASTWriter::AddString(llvm::StringRef Str, RecordData &Record) {

clang/lib/Serialization/ASTWriterDecl.cpp

@@ -133,6 +133,8 @@ void ASTDeclWriter::VisitDecl(Decl *D) {
   Writer.AddSourceLocation(D->getLocation(), Record);
   Record.push_back(D->isInvalidDecl());
   Record.push_back(D->hasAttrs());
+  if (D->hasAttrs())
+    Writer.WriteAttributes(D->getAttrs(), Record);
   Record.push_back(D->isImplicit());
   Record.push_back(D->isUsed(false));
   Record.push_back(D->getAccess());
@@ -1212,10 +1214,6 @@ void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
                             D->getDeclKindName() + "'");
   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
 
-  // If the declaration had any attributes, write them now.
-  if (D->hasAttrs())
-    WriteAttributeRecord(D->getAttrs());
-
   // Flush any expressions that were written as part of this declaration.
   FlushStmts();
 

clang/test/PCH/attrs-PR8406.c

@@ -0,0 +1,23 @@
+// Test this without pch.
+// RUN: %clang_cc1 -include %s -emit-llvm -o - %s | FileCheck %s
+
+// Test with pch.
+// RUN: %clang_cc1 -emit-pch -o %t %s
+// RUN: %clang_cc1 -include-pch %t -emit-llvm -o - %s | FileCheck %s
+
+#ifndef HEADER
+#define HEADER
+
+struct Bar
+{
+  // CHECK: align 512
+  int buffer[123] __attribute__((__aligned__(512)));
+};
+
+#else
+
+void foo() {
+  struct Bar bar;
+}
+
+#endif