chore: import upstream snapshot with attribution

tensorflow/lite/experimental/shlo/overload.h

@@ -0,0 +1,39 @@
+/* Copyright 2024 The TensorFlow Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+#ifndef TENSORFLOW_LITE_EXPERIMENTAL_SHLO_OVERLOAD_H_
+#define TENSORFLOW_LITE_EXPERIMENTAL_SHLO_OVERLOAD_H_
+
+namespace shlo_ref {
+
+// Returns a functor that provides overloads based on the
+// functors passed to it.
+//
+// Useful when used in conjunction with `std::visit`.
+//
+// Use absl version when we know for sure the version we can use.
+template <class... Ts>
+class Overload : public Ts... {
+ public:
+  explicit Overload(Ts&&... ts) : Ts(static_cast<Ts&&>(ts))... {}
+  using Ts::operator()...;
+};
+
+template <class... Ts>
+Overload(Ts&&...) -> Overload<Ts...>;
+
+}  // namespace shlo_ref
+
+#endif  // TENSORFLOW_LITE_EXPERIMENTAL_SHLO_OVERLOAD_H_