Revert r170806, "Fix some bugs where we would sometimes use 0, not -1, when emitting a null constant of type pointer-to-data-member."

It broke stage2.

llvm-svn: 170835

2 files changed, 8 insertions, 5 deletions

diff --git a/clang/lib/CodeGen/CGExprAgg.cpp b/clang/lib/CodeGen/CGExprAgg.cpp
index 0c1e23965df..c7f65bf4202 100644
--- a/clang/lib/CodeGen/CGExprAgg.cpp
+++ b/clang/lib/CodeGen/CGExprAgg.cpp
@@ -931,7 +931,7 @@ AggExprEmitter::EmitInitializationToLValue(Expr* E, LValue LV) {
   // FIXME: Are initializers affected by volatile?
   if (Dest.isZeroed() && isSimpleZero(E, CGF)) {
     // Storing "i32 0" to a zero'd memory location is a noop.
-  } else if (isa<ImplicitValueInitExpr>(E) || isa<CXXScalarValueInitExpr>(E)) {
+  } else if (isa<ImplicitValueInitExpr>(E)) {
     EmitNullInitializationToLValue(LV);
   } else if (type->isReferenceType()) {
     RValue RV = CGF.EmitReferenceBindingToExpr(E, /*InitializedDecl=*/0);
@@ -960,8 +960,8 @@ void AggExprEmitter::EmitNullInitializationToLValue(LValue lv) {
     return;
   
   if (!CGF.hasAggregateLLVMType(type)) {
-    // For non-aggregates, we can store the appropriate null constant.
-    llvm::Value *null = CGF.CGM.EmitNullConstant(type);
+    // For non-aggregates, we can store zero.
+    llvm::Value *null = llvm::Constant::getNullValue(CGF.ConvertType(type));
     // Note that the following is not equivalent to
     // EmitStoreThroughBitfieldLValue for ARC types.
     if (lv.isBitField()) {
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 69f6923963c..9071e693f9e 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -266,7 +266,7 @@ public:
   Value *VisitInitListExpr(InitListExpr *E);
 
   Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
-    return EmitNullValue(E->getType());
+    return CGF.CGM.EmitNullConstant(E->getType());
   }
   Value *VisitExplicitCastExpr(ExplicitCastExpr *E) {
     if (E->getType()->isVariablyModifiedType())
@@ -800,7 +800,10 @@ EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src,
 }
 
 Value *ScalarExprEmitter::EmitNullValue(QualType Ty) {
-  return CGF.CGM.EmitNullConstant(Ty);
+  if (const MemberPointerType *MPT = Ty->getAs<MemberPointerType>())
+    return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT);
+
+  return llvm::Constant::getNullValue(ConvertType(Ty));
 }
 
 /// \brief Emit a sanitization check for the given "binary" operation (which