Add unidirectional sequence rnn support to the NN API delegate

PiperOrigin-RevId: 253204784

tensorflow/lite/delegates/nnapi/nnapi_delegate.cc

@@ -135,6 +135,13 @@ bool IsHybridOperator(const TfLiteContext* context, int builtin_code,
       const TfLiteType weights_type = context->tensors[weights_id].type;
       return IsFloat(input_type) && IsQuantized(weights_type);
     }
+    case kTfLiteBuiltinUnidirectionalSequenceRnn: {
+      const int input_id = node->inputs->data[0];
+      const int weights_id = node->inputs->data[1];
+      const TfLiteType input_type = context->tensors[input_id].type;
+      const TfLiteType weights_type = context->tensors[weights_id].type;
+      return IsFloat(input_type) && IsQuantized(weights_type);
+    }
     default:
       return false;
   }
@@ -1191,6 +1198,22 @@ class NNAPIDelegateKernel {
           }
         }
       } break;
+      case kTfLiteBuiltinUnidirectionalSequenceRnn:
+        if (version == 1 && android_sdk_version >= kMinSdkVersionForNNAPI12) {
+          if (IsHybridOperator(context, builtin_code, node)) {
+            // Hybrid version of this op is not supported by NN API.
+            return nullptr;
+          }
+          return [](const NNAPIOpMappingArgs& mapping_args)
+                     -> ANeuralNetworksOperationType {
+            auto builtin = reinterpret_cast<TfLiteSequenceRNNParams*>(
+                mapping_args.node->builtin_data);
+            mapping_args.builder->AddScalarInt32Operand(builtin->activation);
+            mapping_args.builder->AddScalarInt32Operand(builtin->time_major);
+            return ANEURALNETWORKS_UNIDIRECTIONAL_SEQUENCE_RNN;
+          };
+        }
+        break;
       case kTfLiteBuiltinSpaceToBatchNd:
         if (version == 1 && android_sdk_version >= kMinSdkVersionForNNAPI11) {
           return BasicMappingFn<ANEURALNETWORKS_SPACE_TO_BATCH_ND>;

tensorflow/lite/kernels/BUILD

@@ -852,6 +852,7 @@ cc_test(
     name = "unidirectional_sequence_rnn_test",
     size = "small",
     srcs = ["unidirectional_sequence_rnn_test.cc"],
+    tags = ["tflite_nnapi"],
     deps = [
         ":builtin_ops",
         ":test_main",

tensorflow/lite/nnapi/NeuralNetworksTypes.h

@@ -109,6 +109,7 @@ enum {
   ANEURALNETWORKS_SQRT = 88,
   ANEURALNETWORKS_TILE = 89,
   ANEURALNETWORKS_TOPK_V2 = 90,
+  ANEURALNETWORKS_UNIDIRECTIONAL_SEQUENCE_RNN = 93,
 };
 
 /**