chore: import upstream snapshot with attribution

tensorflow/lite/nnapi/sl/include/SupportLibrary.h

@@ -0,0 +1,99 @@
+/* Copyright 2021 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_NNAPI_SL_INCLUDE_SUPPORT_LIBRARY_H_
+#define TENSORFLOW_LITE_NNAPI_SL_INCLUDE_SUPPORT_LIBRARY_H_
+
+// WARNING: this header file is DEPRECATED.
+// See https://developer.android.com/ndk/guides/neuralnetworks/migration-guide.
+
+#include <dlfcn.h>
+
+#include <cstdlib>
+#include <memory>
+#include <string>
+#include <variant>
+
+// Changed when importing from AOSP
+#include "tensorflow/lite/kernels/internal/compatibility.h"
+#include "tensorflow/lite/nnapi/NeuralNetworksTypes.h"
+#include "tensorflow/lite/nnapi/sl/public/NeuralNetworksSupportLibraryImpl.h"
+
+namespace tflite {
+namespace nnapi {
+
+#ifndef __NNAPI_FL5_MIN_ANDROID_API__
+#define __NNAPI_FL5_MIN_ANDROID_API__ __ANDROID_API_S__
+#endif
+
+/**
+ * Helper struct, wraps different versions of NnApiSLDriverImpl.
+ *
+ * Owns the .so handle, and will close it in destructor.
+ * Sets proper implStructFeatureLevel in constructor.
+ *
+ * There's expectation that for M>N, NnApiSLDriverImplFL(M) is
+ * a strict superset of NnApiSLDriverImplFL(N), and *NnApiSLDriverImplFL(M) can
+ * be reinterpret_cast to *NnApiSLDriverImplFL(N) safely.
+ *
+ * The base->implFeatureLevel is set to the actual Feature Level
+ * implemented by the SLDriverImpl,
+ */
+struct NnApiSupportLibrary {
+  NnApiSupportLibrary(const NnApiSLDriverImplFL5* impl, void* libHandle)
+      : libHandle(libHandle), fl5(impl) {}
+  // No need for ctor below since FL6&7 are typedefs of FL5
+  // NnApiSupportLibrary(const NnApiSLDriverImplFL6& impl, void* libHandle):
+  // impl(impl), NnApiSupportLibrary(const NnApiSLDriverImplFL7& impl, void*
+  // libHandle): impl(impl), libHandle(libHandle) {}
+  ~NnApiSupportLibrary() {
+    if (libHandle != nullptr) {
+      dlclose(libHandle);
+      libHandle = nullptr;
+    }
+  }
+  NnApiSupportLibrary(const NnApiSupportLibrary&) = delete;
+  NnApiSupportLibrary& operator=(const NnApiSupportLibrary&) = delete;
+
+  int64_t getFeatureLevel() const { return fl5->base.implFeatureLevel; }
+
+  const NnApiSLDriverImplFL5* getFL5() const { return fl5; }
+  const NnApiSLDriverImplFL6* getFL6() const {
+    TFLITE_CHECK_GE(getFeatureLevel(), ANEURALNETWORKS_FEATURE_LEVEL_6);
+    return reinterpret_cast<const NnApiSLDriverImplFL6*>(&fl5);
+  }
+  const NnApiSLDriverImplFL7* getFL7() const {
+    TFLITE_CHECK_GE(getFeatureLevel(), ANEURALNETWORKS_FEATURE_LEVEL_7);
+    return reinterpret_cast<const NnApiSLDriverImplFL6*>(&fl5);
+  }
+
+  void* libHandle = nullptr;
+  const NnApiSLDriverImplFL5* fl5;
+};
+
+/**
+ * Loads the NNAPI support library.
+ * The NnApiSupportLibrary structure is filled with all the pointers. If one
+ * function doesn't exist, a null pointer is stored.
+ */
+std::unique_ptr<const NnApiSupportLibrary> loadNnApiSupportLibrary(
+    const std::string& libName);
+std::unique_ptr<const NnApiSupportLibrary> loadNnApiSupportLibrary(
+    void* libHandle);
+
+}  // namespace nnapi
+}  // namespace tflite
+
+#endif  // TENSORFLOW_LITE_NNAPI_SL_INCLUDE_SUPPORT_LIBRARY_H_

tensorflow/lite/nnapi/sl/include/SupportLibrarySymbols.h

@@ -0,0 +1,43 @@
+/* Copyright 2021 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_NNAPI_SL_INCLUDE_SUPPORT_LIBRARY_SYMBOLS_H_
+#define TENSORFLOW_LITE_NNAPI_SL_INCLUDE_SUPPORT_LIBRARY_SYMBOLS_H_
+
+// WARNING: this header file is DEPRECATED.
+// See https://developer.android.com/ndk/guides/neuralnetworks/migration-guide.
+
+#include <stddef.h>
+// Changed when importing from AOSP
+#include "tensorflow/lite/nnapi/sl/public/NeuralNetworksSupportLibraryImpl.h"
+
+// If you are linking against SL driver implementation through DT_NEEDED,
+// you can use this declaration to access its implementation instead
+// of doing dlsym.
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Get the NNAPI SL Driver NnApiSLDriverImpl with all
+ * driver functions.
+ */
+NnApiSLDriverImpl* ANeuralNetworks_getSLDriverImpl();
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif  // TENSORFLOW_LITE_NNAPI_SL_INCLUDE_SUPPORT_LIBRARY_SYMBOLS_H_