Add basic support for properties references (a missing feature).

While it is far from complete, it does fix the following <rdar://problem/5967199> clang on xcode: error: member reference is not to a structure or union



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@51719 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 502dd3b..eb9add9 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -1187,6 +1187,15 @@
   return reinterpret_cast<Stmt**>(&Base)+1;
 }
 
+// ObjCIvarRefExpr
+Stmt::child_iterator ObjCPropertyRefExpr::child_begin() {
+  return reinterpret_cast<Stmt**>(&Base);
+}
+
+Stmt::child_iterator ObjCPropertyRefExpr::child_end() {
+  return reinterpret_cast<Stmt**>(&Base)+1;
+}
+
 // PreDefinedExpr
 Stmt::child_iterator PreDefinedExpr::child_begin() { return child_iterator(); }
 Stmt::child_iterator PreDefinedExpr::child_end() { return child_iterator(); }
diff --git a/lib/AST/StmtPrinter.cpp b/lib/AST/StmtPrinter.cpp
index b55869b..d52f48e 100644
--- a/lib/AST/StmtPrinter.cpp
+++ b/lib/AST/StmtPrinter.cpp
@@ -484,6 +484,14 @@
   OS << Node->getDecl()->getName();
 }
 
+void StmtPrinter::VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *Node) {
+  if (Node->getBase()) {
+    PrintExpr(Node->getBase());
+    OS << ".";
+  }
+  // FIXME: OS << Node->getDecl()->getName();
+}
+
 void StmtPrinter::VisitPreDefinedExpr(PreDefinedExpr *Node) {
   switch (Node->getIdentType()) {
     default:
diff --git a/lib/AST/StmtSerialization.cpp b/lib/AST/StmtSerialization.cpp
index 1e5229e..25e9514 100644
--- a/lib/AST/StmtSerialization.cpp
+++ b/lib/AST/StmtSerialization.cpp
@@ -988,6 +988,21 @@
   return dr;
 }
 
+void ObjCPropertyRefExpr::EmitImpl(Serializer& S) const {
+  S.Emit(Loc);
+  S.Emit(getType());
+  S.EmitPtr(getDecl());
+}
+  
+ObjCPropertyRefExpr* ObjCPropertyRefExpr::CreateImpl(Deserializer& D, 
+                                                     ASTContext& C) {
+  SourceLocation Loc = SourceLocation::ReadVal(D);
+  QualType T = QualType::ReadVal(D);
+  ObjCPropertyRefExpr* dr = new ObjCPropertyRefExpr(NULL,T,Loc,0);
+  D.ReadPtr(dr->D,false);  
+  return dr;
+}
+
 void ObjCMessageExpr::EmitImpl(Serializer& S) const {
   S.EmitBool(getReceiver() ? true : false);
   S.Emit(getType());