+/// Check if a field at position Elt of a MDNode is a MDNode.
+/// We currently allow an empty string and an integer.
+/// But we don't allow a non-empty string in a MDNode field.
+static bool fieldIsMDNode(const MDNode *DbgNode, unsigned Elt) {
+ // FIXME: This function should return true, if the field is null or the field
+ // is indeed a MDNode: return !Fld || isa<MDNode>(Fld).
+ Value *Fld = getField(DbgNode, Elt);
+ if (Fld && isa<MDString>(Fld) &&
+ !cast<MDString>(Fld)->getString().empty())
+ return false;
+ return true;
+}
+
+/// Check if a field at position Elt of a MDNode is a MDString.
+static bool fieldIsMDString(const MDNode *DbgNode, unsigned Elt) {
+ Value *Fld = getField(DbgNode, Elt);
+ return !Fld || isa<MDString>(Fld);
+}
+
+/// Check if a value can be a reference to a type.
+static bool isTypeRef(const Value *Val) {
+ return !Val ||
+ (isa<MDString>(Val) && !cast<MDString>(Val)->getString().empty()) ||
+ (isa<MDNode>(Val) && DIType(cast<MDNode>(Val)).isType());
+}
+
+/// Check if a field at position Elt of a MDNode can be a reference to a type.
+static bool fieldIsTypeRef(const MDNode *DbgNode, unsigned Elt) {
+ Value *Fld = getField(DbgNode, Elt);
+ return isTypeRef(Fld);
+}
+
+/// Check if a value can be a ScopeRef.
+static bool isScopeRef(const Value *Val) {
+ return !Val ||
+ (isa<MDString>(Val) && !cast<MDString>(Val)->getString().empty()) ||
+ (isa<MDNode>(Val) && DIScope(cast<MDNode>(Val)).isScope());
+}
+
+/// Check if a field at position Elt of a MDNode can be a ScopeRef.
+static bool fieldIsScopeRef(const MDNode *DbgNode, unsigned Elt) {
+ Value *Fld = getField(DbgNode, Elt);
+ return isScopeRef(Fld);
+}
+