Implement PCH support for C++ namespaces.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@96738 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/AST/Decl.h b/include/clang/AST/Decl.h
index 712e8b0..91aeff3 100644
--- a/include/clang/AST/Decl.h
+++ b/include/clang/AST/Decl.h
@@ -267,8 +267,8 @@
   }
 
   void setAnonymousNamespace(NamespaceDecl *D) {
-    assert(D->isAnonymousNamespace());
-    assert(D->getParent() == this);
+    assert(!D || D->isAnonymousNamespace());
+    assert(!D || D->getParent() == this);
     AnonymousNamespace = D;
   }
 
diff --git a/include/clang/Frontend/PCHBitCodes.h b/include/clang/Frontend/PCHBitCodes.h
index e22d37b..d4014b3 100644
--- a/include/clang/Frontend/PCHBitCodes.h
+++ b/include/clang/Frontend/PCHBitCodes.h
@@ -524,7 +524,9 @@
       /// associates a declaration name with one or more declaration
       /// IDs. This data is used when performing qualified name lookup
       /// into a DeclContext via DeclContext::lookup.
-      DECL_CONTEXT_VISIBLE
+      DECL_CONTEXT_VISIBLE,
+      /// \brief A NamespaceDecl record.
+      DECL_NAMESPACE
     };
 
     /// \brief Record codes for each kind of statement or expression.
diff --git a/lib/Frontend/PCHReaderDecl.cpp b/lib/Frontend/PCHReaderDecl.cpp
index af69664..27349ec 100644
--- a/lib/Frontend/PCHReaderDecl.cpp
+++ b/lib/Frontend/PCHReaderDecl.cpp
@@ -39,6 +39,7 @@
     void VisitDecl(Decl *D);
     void VisitTranslationUnitDecl(TranslationUnitDecl *TU);
     void VisitNamedDecl(NamedDecl *ND);
+    void VisitNamespaceDecl(NamespaceDecl *D);
     void VisitTypeDecl(TypeDecl *TD);
     void VisitTypedefDecl(TypedefDecl *TD);
     void VisitTagDecl(TagDecl *TD);
@@ -96,6 +97,18 @@
   ND->setDeclName(Reader.ReadDeclarationName(Record, Idx));
 }
 
+void PCHDeclReader::VisitNamespaceDecl(NamespaceDecl *D) {
+  VisitNamedDecl(D);
+  D->setLBracLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  D->setRBracLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  D->setNextNamespace(
+                    cast_or_null<NamespaceDecl>(Reader.GetDecl(Record[Idx++])));
+  D->setOriginalNamespace(
+                    cast_or_null<NamespaceDecl>(Reader.GetDecl(Record[Idx++])));
+  D->setAnonymousNamespace(
+                    cast_or_null<NamespaceDecl>(Reader.GetDecl(Record[Idx++])));
+}
+
 void PCHDeclReader::VisitTypeDecl(TypeDecl *TD) {
   VisitNamedDecl(TD);
   TD->setTypeForDecl(Reader.GetType(Record[Idx++]).getTypePtr());
@@ -743,6 +756,10 @@
   case pch::DECL_BLOCK:
     D = BlockDecl::Create(*Context, 0, SourceLocation());
     break;
+      
+  case pch::DECL_NAMESPACE:
+    D = NamespaceDecl::Create(*Context, 0, SourceLocation(), 0);
+    break;
   }
 
   assert(D && "Unknown declaration reading PCH file");
diff --git a/lib/Frontend/PCHWriterDecl.cpp b/lib/Frontend/PCHWriterDecl.cpp
index d105382..e776d32 100644
--- a/lib/Frontend/PCHWriterDecl.cpp
+++ b/lib/Frontend/PCHWriterDecl.cpp
@@ -42,6 +42,7 @@
     void VisitDecl(Decl *D);
     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
     void VisitNamedDecl(NamedDecl *D);
+    void VisitNamespaceDecl(NamespaceDecl *D);
     void VisitTypeDecl(TypeDecl *D);
     void VisitTypedefDecl(TypedefDecl *D);
     void VisitTagDecl(TagDecl *D);
@@ -99,6 +100,16 @@
   Writer.AddDeclarationName(D->getDeclName(), Record);
 }
 
+void PCHDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
+  VisitNamedDecl(D);
+  Writer.AddSourceLocation(D->getLBracLoc(), Record);
+  Writer.AddSourceLocation(D->getRBracLoc(), Record);
+  Writer.AddDeclRef(D->getNextNamespace(), Record);
+  Writer.AddDeclRef(D->getOriginalNamespace(), Record);
+  Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
+  Code = pch::DECL_NAMESPACE;
+}
+
 void PCHDeclWriter::VisitTypeDecl(TypeDecl *D) {
   VisitNamedDecl(D);
   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);