Reinstate r170806, reverted in r170835, with a fix use i1 instead of i8 for a value-initialized bool!


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170837 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprAgg.cpp b/lib/CodeGen/CGExprAgg.cpp
index c7f65bf..0c1e239 100644
--- a/lib/CodeGen/CGExprAgg.cpp
+++ b/lib/CodeGen/CGExprAgg.cpp
@@ -931,7 +931,7 @@
   // 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)) {
+  } else if (isa<ImplicitValueInitExpr>(E) || isa<CXXScalarValueInitExpr>(E)) {
     EmitNullInitializationToLValue(LV);
   } else if (type->isReferenceType()) {
     RValue RV = CGF.EmitReferenceBindingToExpr(E, /*InitializedDecl=*/0);
@@ -960,8 +960,8 @@
     return;
   
   if (!CGF.hasAggregateLLVMType(type)) {
-    // For non-aggregates, we can store zero.
-    llvm::Value *null = llvm::Constant::getNullValue(CGF.ConvertType(type));
+    // For non-aggregates, we can store the appropriate null constant.
+    llvm::Value *null = CGF.CGM.EmitNullConstant(type);
     // Note that the following is not equivalent to
     // EmitStoreThroughBitfieldLValue for ARC types.
     if (lv.isBitField()) {
diff --git a/lib/CodeGen/CGExprScalar.cpp b/lib/CodeGen/CGExprScalar.cpp
index 9071e69..61126e1 100644
--- a/lib/CodeGen/CGExprScalar.cpp
+++ b/lib/CodeGen/CGExprScalar.cpp
@@ -266,7 +266,7 @@
   Value *VisitInitListExpr(InitListExpr *E);
 
   Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
-    return CGF.CGM.EmitNullConstant(E->getType());
+    return EmitNullValue(E->getType());
   }
   Value *VisitExplicitCastExpr(ExplicitCastExpr *E) {
     if (E->getType()->isVariablyModifiedType())
@@ -800,10 +800,7 @@
 }
 
 Value *ScalarExprEmitter::EmitNullValue(QualType Ty) {
-  if (const MemberPointerType *MPT = Ty->getAs<MemberPointerType>())
-    return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT);
-
-  return llvm::Constant::getNullValue(ConvertType(Ty));
+  return CGF.EmitFromMemory(CGF.CGM.EmitNullConstant(Ty), Ty);
 }
 
 /// \brief Emit a sanitization check for the given "binary" operation (which