In the serialized AST format, make the translation unit a "predefined"

declaration that never actually gets serialized. Instead, serialize
the various kinds of update records (lexical decls, visible decls, the
addition of an anonymous namespace) for the translation unit, even if
we're not chaining. This way, we won't have to deal with multiple
loaded translation unit declarations.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@137395 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 21 insertions, 18 deletions

diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 707ee8a8bb..02bd21fef0 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -243,8 +243,7 @@ void ASTDeclReader::VisitDecl(Decl *D) {
 }
 
 void ASTDeclReader::VisitTranslationUnitDecl(TranslationUnitDecl *TU) {
-  VisitDecl(TU);
-  TU->setAnonymousNamespace(ReadDeclAs<NamespaceDecl>(Record, Idx));
+  llvm_unreachable("Translation units are not serialized");
 }
 
 void ASTDeclReader::VisitNamedDecl(NamedDecl *ND) {
@@ -1444,7 +1443,7 @@ void ASTReader::loadAndAttachPreviousDecl(Decl *D, serialization::DeclID ID) {
 
 /// \brief Read the declaration at the given offset from the AST file.
 Decl *ASTReader::ReadDeclRecord(DeclID ID) {
-  unsigned Index = ID - 1;
+  unsigned Index = ID - NUM_PREDEF_DECL_IDS;
   RecordLocation Loc = DeclCursorForID(ID);
   llvm::BitstreamCursor &DeclsCursor = Loc.F->DeclsCursor;
   // Keep track of where we are in the stream, then jump back there
@@ -1468,11 +1467,6 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
   case DECL_CONTEXT_VISIBLE:
     assert(false && "Record cannot be de-serialized with ReadDeclRecord");
     break;
-  case DECL_TRANSLATION_UNIT:
-    assert(Index == Loc.F->BaseDeclID && 
-           "Translation unit must be at first index in file");
-    D = Context->getTranslationUnitDecl();
-    break;
   case DECL_TYPEDEF:
     D = TypedefDecl::Create(*Context, 0, SourceLocation(), SourceLocation(),
                             0, 0);
@@ -1727,6 +1721,20 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
   }
   assert(Idx == Record.size());
 
+  // Load any relevant update records.
+  loadDeclUpdateRecords(ID, D);
+  
+  // If we have deserialized a declaration that has a definition the
+  // AST consumer might need to know about, queue it.
+  // We don't pass it to the consumer immediately because we may be in recursive
+  // loading, and some declarations may still be initializing.
+  if (isConsumerInterestedIn(D))
+    InterestingDecls.push_back(D);
+
+  return D;
+}
+
+void ASTReader::loadDeclUpdateRecords(serialization::DeclID ID, Decl *D) {
   // The declaration may have been modified by files later in the chain.
   // If this is the case, read the record containing the updates from each file
   // and pass it to ASTDeclReader to make the modifications.
@@ -1734,7 +1742,7 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
   if (UpdI != DeclUpdateOffsets.end()) {
     FileOffsetsTy &UpdateOffsets = UpdI->second;
     for (FileOffsetsTy::iterator
-           I = UpdateOffsets.begin(), E = UpdateOffsets.end(); I != E; ++I) {
+         I = UpdateOffsets.begin(), E = UpdateOffsets.end(); I != E; ++I) {
       Module *F = I->first;
       uint64_t Offset = I->second;
       llvm::BitstreamCursor &Cursor = F->DeclsCursor;
@@ -1745,20 +1753,15 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
       unsigned RecCode = Cursor.ReadRecord(Code, Record);
       (void)RecCode;
       assert(RecCode == DECL_UPDATES && "Expected DECL_UPDATES record!");
+      
+      unsigned Idx = 0;
+      ASTDeclReader Reader(*this, *F, Cursor, ID, Record, Idx);
       Reader.UpdateDecl(D, *F, Record);
     }
   }
-
-  // If we have deserialized a declaration that has a definition the
-  // AST consumer might need to know about, queue it.
-  // We don't pass it to the consumer immediately because we may be in recursive
-  // loading, and some declarations may still be initializing.
-  if (isConsumerInterestedIn(D))
-    InterestingDecls.push_back(D);
-
-  return D;
 }
 
+
 void ASTDeclReader::UpdateDecl(Decl *D, Module &Module,
                                const RecordData &Record) {
   unsigned Idx = 0;