fix PR4067: [Linux kernel] cannot aggregate codegen stmtexpr as lvalue

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70067 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 22 insertions, 5 deletions

diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index c49592eae8..86993fbe15 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -168,8 +168,10 @@ LValue CodeGenFunction::EmitLValue(const Expr *E) {
   case Expr::ObjCKVCRefExprClass:
     return EmitObjCKVCRefLValue(cast<ObjCKVCRefExpr>(E));
   case Expr::ObjCSuperExprClass:
-    return EmitObjCSuperExpr(cast<ObjCSuperExpr>(E));
+    return EmitObjCSuperExprLValue(cast<ObjCSuperExpr>(E));
 
+  case Expr::StmtExprClass:
+    return EmitStmtExprLValue(cast<StmtExpr>(E));
   case Expr::UnaryOperatorClass: 
     return EmitUnaryOpLValue(cast<UnaryOperator>(E));
   case Expr::ArraySubscriptExprClass:
@@ -1195,10 +1197,21 @@ CodeGenFunction::EmitObjCKVCRefLValue(const ObjCKVCRefExpr *E) {
 }
 
 LValue
-CodeGenFunction::EmitObjCSuperExpr(const ObjCSuperExpr *E) {
+CodeGenFunction::EmitObjCSuperExprLValue(const ObjCSuperExpr *E) {
   return EmitUnsupportedLValue(E, "use of super");
 }
 
+LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
+  
+  // Can only get l-value for message expression returning aggregate type
+  RValue RV = EmitAnyExprToTemp(E);
+  // FIXME: can this be volatile?
+  return LValue::MakeAddr(RV.getAggregateAddr(),
+                          E->getType().getCVRQualifiers(),
+                          getContext().getObjCGCAttrKind(E->getType()));
+}
+
+
 RValue CodeGenFunction::EmitCallExpr(llvm::Value *Callee, QualType CalleeType, 
                                      CallExpr::const_arg_iterator ArgBeg,
                                      CallExpr::const_arg_iterator ArgEnd,
diff --git a/lib/CodeGen/CGExprAgg.cpp b/lib/CodeGen/CGExprAgg.cpp
index 2e45f2017b..a74741290b 100644
--- a/lib/CodeGen/CGExprAgg.cpp
+++ b/lib/CodeGen/CGExprAgg.cpp
@@ -78,8 +78,6 @@ public:
   }
   
   // Operators.
-  //  case Expr::UnaryOperatorClass:
-  //  case Expr::CastExprClass: 
   void VisitCStyleCastExpr(CStyleCastExpr *E);
   void VisitImplicitCastExpr(ImplicitCastExpr *E);
   void VisitCallExpr(const CallExpr *E);
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 2cad46ed01..9fc59527ce 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -645,7 +645,8 @@ public:
   LValue EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E);
   LValue EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E);
   LValue EmitObjCKVCRefLValue(const ObjCKVCRefExpr *E);
-  LValue EmitObjCSuperExpr(const ObjCSuperExpr *E);
+  LValue EmitObjCSuperExprLValue(const ObjCSuperExpr *E);
+  LValue EmitStmtExprLValue(const StmtExpr *E);
 
   //===--------------------------------------------------------------------===//
   //                         Scalar Expression Emission
diff --git a/test/CodeGen/exprs.c b/test/CodeGen/exprs.c
index f80ee41958..ad3e4e0956 100644
--- a/test/CodeGen/exprs.c
+++ b/test/CodeGen/exprs.c
@@ -99,3 +99,8 @@ int f6(int a0, struct s6 a1, struct s6 a2) {
 void f7() {
   __func__;
 }
+
+// PR4067
+int f8() {
+  return ({ foo(); }).Y;
+}