chore: import upstream snapshot with attribution

tensorflow/lite/delegates/hexagon/java/AndroidManifest.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="org.tensorflow.lite">
+
+    <uses-sdk
+        android:targetSdkVersion="19" />
+
+    <application />
+
+</manifest>
+

tensorflow/lite/delegates/hexagon/java/BUILD

@@ -0,0 +1,73 @@
+load("@build_bazel_rules_android//android:rules.bzl", "android_library")
+load("@rules_cc//cc:cc_library.bzl", "cc_library")
+load("//tensorflow/lite:build_def.bzl", "tflite_jni_binary", "tflite_jni_linkopts")
+load("//tensorflow/lite/java:aar_with_jni.bzl", "aar_with_jni")
+
+package(
+    # copybara:uncomment default_applicable_licenses = ["//tensorflow:LICENSE"],
+    default_visibility = ["//visibility:public"],
+    licenses = ["notice"],
+)
+
+# EXPERIMENTAL: Native target that runs inference on the Hexagon backend.
+# The Hexagon backend-related targets are intentionally not included in BUILD.bazel.
+tflite_jni_binary(
+    name = "libtensorflowlite_hexagon_jni.so",
+    linkopts = tflite_jni_linkopts() + select({
+        "//tensorflow:android": ["-ldl"],
+        "//conditions:default": [],
+    }),
+    linkscript = "//tensorflow/lite/delegates/hexagon:version_script.lds",
+    tags = [
+        "manual",
+        "nobuilder",
+        "notap",
+    ],
+    deps = [
+        "//tensorflow/lite/delegates/hexagon/java/src/main/native",
+    ],
+)
+
+cc_library(
+    name = "tensorflowlite_hexagon",
+    srcs = [
+        "libtensorflowlite_hexagon_jni.so",
+    ] + select({
+        # copybara:uncomment_begin(separate repo in OSS)
+        # "//tensorflow:android_arm64": ["//tensorflow/lite/delegates/hexagon/hexagon_nn:libhexagon_interface.so"],
+        # "//tensorflow:android_arm": ["//tensorflow/lite/delegates/hexagon/hexagon_nn:libhexagon_interface.so"],
+        # copybara:uncomment_end_and_comment_begin
+        "//tensorflow:android_arm64": ["@hexagon_nn//:hexagon/arm64-v8a/libhexagon_interface.so"],
+        "//tensorflow:android_arm": ["@hexagon_nn//:hexagon/armeabi-v7a/libhexagon_interface.so"],
+        # copybara:comment_end
+        "//conditions:default": [],
+    }),
+    tags = [
+        "manual",
+        "nobuilder",
+        "notap",
+    ],
+)
+
+android_library(
+    name = "tensorflowlite_java_hexagon",
+    srcs = ["//tensorflow/lite/delegates/hexagon/java/src/main/java/org/tensorflow/lite:hexagon_delegate"],
+    manifest = "AndroidManifest.xml",
+    proguard_specs = ["proguard.flags"],
+    tags = [
+        "manual",
+        "nobuilder",
+        "notap",
+    ],
+    deps = [
+        ":tensorflowlite_hexagon",
+        "//tensorflow/lite/java:tensorflowlite_java",
+        "@org_checkerframework_qual",
+    ],
+)
+
+aar_with_jni(
+    name = "tensorflow-lite-hexagon",
+    android_library = ":tensorflowlite_java_hexagon",
+    headers = ["//tensorflow/lite/delegates/hexagon:hexagon_delegate.h"],
+)

tensorflow/lite/delegates/hexagon/java/proguard.flags

@@ -0,0 +1,3 @@
+-keepclassmembers class org.tensorflow.lite.NativeInterpreterWrapper {
+    private long inferenceDurationNanoseconds;
+}

tensorflow/lite/delegates/hexagon/java/src/main/java/org/tensorflow/lite/BUILD

@@ -0,0 +1,9 @@
+# copybara:uncomment package(default_applicable_licenses = ["//tensorflow:LICENSE"])
+
+licenses(["notice"])
+
+filegroup(
+    name = "hexagon_delegate",
+    srcs = ["HexagonDelegate.java"],
+    visibility = ["//visibility:public"],
+)

tensorflow/lite/delegates/hexagon/java/src/main/java/org/tensorflow/lite/HexagonDelegate.java

@@ -0,0 +1,78 @@
+/* Copyright 2019 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.
+==============================================================================*/
+package org.tensorflow.lite;
+
+import android.content.Context;
+import java.io.Closeable;
+
+/** {@link Delegate} for Hexagon inference. */
+public class HexagonDelegate implements Delegate, Closeable {
+
+  private static final long INVALID_DELEGATE_HANDLE = 0;
+  private static final String TFLITE_HEXAGON_LIB = "tensorflowlite_hexagon_jni";
+  private static volatile boolean nativeLibraryLoaded = false;
+
+  private long delegateHandle;
+
+  /*
+   * Creates a new HexagonDelegate object given the current 'context'.
+   * Throws UnsupportedOperationException if Hexagon DSP delegation is not available
+   * on this device.
+   */
+  public HexagonDelegate(Context context) throws UnsupportedOperationException {
+    ensureNativeLibraryLoaded();
+    setAdspLibraryPath(context.getApplicationInfo().nativeLibraryDir);
+    delegateHandle = createDelegate();
+    if (delegateHandle == INVALID_DELEGATE_HANDLE) {
+      throw new UnsupportedOperationException("This Device doesn't support Hexagon DSP execution.");
+    }
+  }
+
+  @Override
+  public long getNativeHandle() {
+    return delegateHandle;
+  }
+
+  /**
+   * Frees TFLite resources in C runtime.
+   *
+   * <p>User is expected to call this method explicitly.
+   */
+  @Override
+  public void close() {
+    if (delegateHandle != INVALID_DELEGATE_HANDLE) {
+      deleteDelegate(delegateHandle);
+      delegateHandle = INVALID_DELEGATE_HANDLE;
+    }
+  }
+
+  private static void ensureNativeLibraryLoaded() {
+    if (nativeLibraryLoaded) {
+      return;
+    }
+    try {
+      System.loadLibrary(TFLITE_HEXAGON_LIB);
+      nativeLibraryLoaded = true;
+    } catch (Exception e) {
+      throw new UnsupportedOperationException("Failed to load native Hexagon shared library: " + e);
+    }
+  }
+
+  private static native long createDelegate();
+
+  private static native void deleteDelegate(long delegateHandle);
+
+  private static native boolean setAdspLibraryPath(String libraryPath);
+}

tensorflow/lite/delegates/hexagon/java/src/main/native/BUILD

@@ -0,0 +1,30 @@
+# Description:
+# Java Native Interface (JNI) library intended for implementing the
+# TensorFlow Lite Hexagon delegate Java API using the TensorFlow Lite CC library.
+
+load("@rules_cc//cc:cc_library.bzl", "cc_library")
+load("//tensorflow/lite:build_def.bzl", "tflite_copts")
+
+package(
+    # copybara:uncomment default_applicable_licenses = ["//tensorflow:LICENSE"],
+    default_visibility = ["//tensorflow/lite/delegates/hexagon/java:__subpackages__"],
+)
+
+licenses(["notice"])
+
+cc_library(
+    name = "native",
+    srcs = ["hexagon_delegate_jni.cc"],
+    copts = tflite_copts(),
+    tags = [
+        "manual",
+        "nobuilder",
+        "notap",
+    ],
+    deps = [
+        "//tensorflow/lite/c:c_api_types",
+        "//tensorflow/lite/delegates/hexagon:hexagon_delegate",
+        "//tensorflow/lite/java/jni",
+    ],
+    alwayslink = 1,
+)

tensorflow/lite/delegates/hexagon/java/src/main/native/hexagon_delegate_jni.cc

@@ -0,0 +1,53 @@
+/* Copyright 2019 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.
+==============================================================================*/
+#include <jni.h>
+
+#include <sstream>
+
+#include "tensorflow/lite/c/c_api_types.h"
+#include "tensorflow/lite/delegates/hexagon/hexagon_delegate.h"
+
+extern "C" {
+
+JNIEXPORT jlong JNICALL
+Java_org_tensorflow_lite_HexagonDelegate_createDelegate(
+    JNIEnv* env, jclass clazz) {
+  // Auto-choosing the best performing config for closed release.
+  TfLiteHexagonDelegateOptions options = {0};
+  TfLiteHexagonInit();
+  return reinterpret_cast<jlong>(TfLiteHexagonDelegateCreate(&options));
+}
+
+JNIEXPORT void JNICALL
+Java_org_tensorflow_lite_HexagonDelegate_deleteDelegate(
+    JNIEnv* env, jclass clazz, jlong delegate) {
+  TfLiteHexagonDelegateDelete(reinterpret_cast<TfLiteDelegate*>(delegate));
+  TfLiteHexagonTearDown();
+}
+
+JNIEXPORT jboolean JNICALL
+Java_org_tensorflow_lite_HexagonDelegate_setAdspLibraryPath(
+    JNIEnv* env, jclass clazz, jstring native_lib_path) {
+  const char* lib_dir_path = env->GetStringUTFChars(native_lib_path, nullptr);
+  std::stringstream path;
+  path << lib_dir_path
+       << ";/system/lib/rfsa/adsp;/system/vendor/lib/rfsa/adsp;/dsp";
+  env->ReleaseStringUTFChars(native_lib_path, lib_dir_path);
+  return setenv("ADSP_LIBRARY_PATH", path.str().c_str(), 1 /*override*/) == 0
+             ? JNI_TRUE
+             : JNI_FALSE;
+}
+
+}  // extern "C"