#
# Copyright (C) 2019 The Android Open Source Project
#
# 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.
#
import numpy as np
import sys


def convert_to_time_major(tensor, tensor_shape):
  return np.array(tensor).reshape(tensor_shape).transpose(
      [1, 0, 2]).flatten().tolist()


def merge_outputs(a, a_shape, b, b_shape):
  a = np.array(a).reshape(a_shape)
  b = np.array(b).reshape(b_shape)
  return np.concatenate((a, b), axis=2).flatten().tolist()

def reverse_batch_major(tensor, tensor_shape):
  return np.array(tensor).reshape(tensor_shape)[:, ::-1, :].flatten().tolist()

def split_tensor_in_two(tensor, tensor_shape):
  tensor = np.array(tensor).reshape(tensor_shape)
  left, right = np.split(tensor, 2, axis=len(tensor_shape) - 1)
  return left.flatten().tolist(), right.flatten().tolist()

def test(name, input, fw_weights, fw_recurrent_weights, fw_bias,
         fw_hidden_state, bw_weights, bw_recurrent_weights, bw_bias,
         bw_hidden_state, aux_input, fw_aux_weights, bw_aux_weights, activation,
         time_major, merge_outputs, fw_output, bw_output, input_data,
         fw_weights_data, fw_recurrent_weights_data, fw_bias_data,
         fw_hidden_state_data, bw_weights_data, bw_recurrent_weights_data,
         bw_bias_data, bw_hidden_state_data, aux_input_data,
         fw_aux_weights_data, bw_aux_weights_data, fw_output_data,
         bw_output_data):
  activation = Int32Scalar("activation", activation)
  time_major = BoolScalar("time_major", time_major)
  merge_outputs_scalar = BoolScalar("merge_outputs", merge_outputs)
  model = Model().Operation(
      "BIDIRECTIONAL_SEQUENCE_RNN", input, fw_weights, fw_recurrent_weights,
      fw_bias, fw_hidden_state, bw_weights, bw_recurrent_weights, bw_bias,
      bw_hidden_state, aux_input, fw_aux_weights, bw_aux_weights, activation,
      time_major, merge_outputs_scalar)
  # Models with parallel linking will pass validation for version 1.2 since they
  # have the same number of inputs and outputs with the same types. To
  # distinguish parallel linking models, we need to know which inputs are
  # omitted. This information is available only at preparation stage. To pass
  # the compliance tests, we say here that the model was introduced in 1.2.
  model = model.IntroducedIn("V1_2")
  if merge_outputs:
    model = model.To(fw_output)
  else:
    model = model.To(fw_output, bw_output)

  data_dict = {
      input: input_data,
      fw_weights: fw_weights_data,
      fw_recurrent_weights: fw_recurrent_weights_data,
      fw_bias: fw_bias_data,
      fw_hidden_state: fw_hidden_state_data,
      bw_weights: bw_weights_data,
      bw_recurrent_weights: bw_recurrent_weights_data,
      bw_bias: bw_bias_data,
      bw_hidden_state: bw_hidden_state_data,
      aux_input: aux_input_data,
      fw_aux_weights: fw_aux_weights_data,
      bw_aux_weights: bw_aux_weights_data,
      fw_output: fw_output_data,
  }
  if not merge_outputs:
    data_dict[bw_output] = bw_output_data

  example = Example(
      data_dict, model=model, name=name).AddVariations("relaxed", "float16")


num_batches = 2
max_time = 16
input_size = 8
fw_num_units = 16
bw_num_units = 16

input_data = [
    0.23689353, 0.285385, 0.037029743, -0.19858193, -0.27569133, 0.43773448,
    0.60379338, 0.35562468, -0.69424844, -0.93421471, -0.87287879, 0.37144363,
    -0.62476718, 0.23791671, 0.40060222, 0.1356622, -0.99774903, -0.98858172,
    -0.38952237, -0.47685933, 0.31073618, 0.71511042, -0.63767755, -0.31729108,
    0.33468103, 0.75801885, 0.30660987, -0.37354088, 0.77002847, -0.62747043,
    -0.68572164, 0.0069220066, 0.65791464, 0.35130811, 0.80834007, -0.61777675,
    -0.21095741, 0.41213346, 0.73784804, 0.094794154, 0.47791874, 0.86496925,
    -0.53376222, 0.85315156, 0.10288584, 0.86684, -0.011186242, 0.10513687,
    0.87825835, 0.59929144, 0.62827742, 0.18899453, 0.31440187, 0.99059987,
    0.87170351, -0.35091716, 0.74861872, 0.17831337, 0.2755419, 0.51864719,
    0.55084288, 0.58982027, -0.47443086, 0.20875752, -0.058871567, -0.66609079,
    0.59098077, 0.73017097, 0.74604273, 0.32882881, -0.17503482, 0.22396147,
    0.19379807, 0.29120302, 0.077113032, -0.70331609, 0.15804303, -0.93407321,
    0.40182066, 0.036301374, 0.66521823, 0.0300982, -0.7747041, -0.02038002,
    0.020698071, -0.90300065, 0.62870288, -0.23068321, 0.27531278, -0.095755219,
    -0.712036, -0.17384434, -0.50593495, -0.18646687, -0.96508682, 0.43519354,
    0.14744234, 0.62589407, 0.1653645, -0.10651493, -0.045277178, 0.99032974,
    -0.88255352, -0.85147917, 0.28153265, 0.19455957, -0.55479527, -0.56042433,
    0.26048636, 0.84702539, 0.47587705, -0.074295521, -0.12287641, 0.70117295,
    0.90532446, 0.89782166, 0.79817224, 0.53402734, -0.33286154, 0.073485017,
    -0.56172788, -0.044897556, 0.89964068, -0.067662835, 0.76863563, 0.93455386,
    -0.6324693, -0.083922029
] * 2

weights_data = [
    0.461459, 0.153381, 0.529743, -0.00371218, 0.676267, -0.211346, 0.317493,
    0.969689, -0.343251, 0.186423, 0.398151, 0.152399, 0.448504, 0.317662,
    0.523556, -0.323514, 0.480877, 0.333113, -0.757714, -0.674487, -0.643585,
    0.217766, -0.0251462, 0.79512, -0.595574, -0.422444, 0.371572, -0.452178,
    -0.556069, -0.482188, -0.685456, -0.727851, 0.841829, 0.551535, -0.232336,
    0.729158, -0.00294906, -0.69754, 0.766073, -0.178424, 0.369513, -0.423241,
    0.548547, -0.0152023, -0.757482, -0.85491, 0.251331, -0.989183, 0.306261,
    -0.340716, 0.886103, -0.0726757, -0.723523, -0.784303, 0.0354295, 0.566564,
    -0.485469, -0.620498, 0.832546, 0.697884, -0.279115, 0.294415, -0.584313,
    0.548772, 0.0648819, 0.968726, 0.723834, -0.0080452, -0.350386, -0.272803,
    0.115121, -0.412644, -0.824713, -0.992843, -0.592904, -0.417893, 0.863791,
    -0.423461, -0.147601, -0.770664, -0.479006, 0.654782, 0.587314, -0.639158,
    0.816969, -0.337228, 0.659878, 0.73107, 0.754768, -0.337042, 0.0960841,
    0.368357, 0.244191, -0.817703, -0.211223, 0.442012, 0.37225, -0.623598,
    -0.405423, 0.455101, 0.673656, -0.145345, -0.511346, -0.901675, -0.81252,
    -0.127006, 0.809865, -0.721884, 0.636255, 0.868989, -0.347973, -0.10179,
    -0.777449, 0.917274, 0.819286, 0.206218, -0.00785118, 0.167141, 0.45872,
    0.972934, -0.276798, 0.837861, 0.747958, -0.0151566, -0.330057, -0.469077,
    0.277308, 0.415818
]

recurrent_weights_data = [
    0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0.1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.1
]

bias_data = [
    0.065691948, -0.69055247, 0.1107955, -0.97084129, -0.23957068, -0.23566568,
    -0.389184, 0.47481549, -0.4791103, 0.29931796, 0.10463274, 0.83918178,
    0.37197268, 0.61957061, 0.3956964, -0.37609905
]

fw_output_data = [
    0.496726, 0, 0.965996, 0, 0.0584254, 0, 0, 0.12315, 0, 0, 0.612266,
    0.456601, 0, 0.52286, 1.16099, 0.0291232, 0, 0, 0.524901, 0, 0, 0, 0,
    1.02116, 0, 1.35762, 0, 0.356909, 0.436415, 0.0355727, 0, 0, 0, 0, 0,
    0.262335, 0, 0, 0, 1.33992, 0, 2.9739, 0, 0, 1.31914, 2.66147, 0, 0,
    0.942568, 0, 0, 0, 0.025507, 0, 0, 0, 0.321429, 0.569141, 1.25274, 1.57719,
    0.8158, 1.21805, 0.586239, 0.25427, 1.04436, 0, 0.630725, 0, 0.133801,
    0.210693, 0.363026, 0, 0.533426, 0, 1.25926, 0.722707, 0, 1.22031, 1.30117,
    0.495867, 0.222187, 0, 0.72725, 0, 0.767003, 0, 0, 0.147835, 0, 0, 0,
    0.608758, 0.469394, 0.00720298, 0.927537, 0, 0.856974, 0.424257, 0, 0,
    0.937329, 0, 0, 0, 0.476425, 0, 0.566017, 0.418462, 0.141911, 0.996214,
    1.13063, 0, 0.967899, 0, 0, 0, 0.0831304, 0, 0, 1.00378, 0, 0, 0, 1.44818,
    1.01768, 0.943891, 0.502745, 0, 0.940135, 0, 0, 0, 0, 0, 0, 2.13243, 0,
    0.71208, 0.123918, 1.53907, 1.30225, 1.59644, 0.70222, 0, 0.804329, 0,
    0.430576, 0, 0.505872, 0.509603, 0.343448, 0, 0.107756, 0.614544, 1.44549,
    1.52311, 0.0454298, 0.300267, 0.562784, 0.395095, 0.228154, 0, 0.675323, 0,
    1.70536, 0.766217, 0, 0, 0, 0.735363, 0.0759267, 1.91017, 0.941888, 0, 0, 0,
    0, 0, 1.5909, 0, 0, 0, 0, 0.5755, 0, 0.184687, 0, 1.56296, 0.625285, 0, 0,
    0, 0, 0, 0.0857888, 0, 0, 0, 0, 0.488383, 0.252786, 0, 0, 0, 1.02817,
    1.85665, 0, 0, 0.00981836, 0, 1.06371, 0, 0, 0, 0, 0, 0, 0.290445, 0.316406,
    0, 0.304161, 1.25079, 0.0707152, 0, 0.986264, 0.309201, 0, 0, 0, 0, 0,
    1.64896, 0.346248, 0, 0.918175, 0.78884, 0.524981, 1.92076, 2.07013,
    0.333244, 0.415153, 0.210318, 0, 0, 0, 0, 0, 2.02616, 0, 0.728256, 0.84183,
    0.0907453, 0.628881, 3.58099, 1.49974, 0
] * 2

bw_output_data = [
    0.496726, 0, 1.00883, 0, 0.0584256, 0, 0, 0.236412, 0, 0, 0.612267,
    0.487726, 0, 0.54883, 1.16099, 0.0291233, 0, 0, 0.428302, 0, 0, 0, 0,
    1.13262, 0, 1.64415, 0, 0.311249, 0.570804, 0.259696, 0, 0, 0, 0, 0,
    0.262334, 0, 0, 0, 1.23781, 0, 2.86532, 0, 0, 1.34389, 2.76409, 0, 0,
    1.03969, 0, 0.00410865, 0, 0.0470295, 0, 0, 0, 0.371556, 0.27175, 1.36614,
    1.63956, 0.683887, 1.06176, 0.719552, 0.301314, 0.971195, 0, 0.697143, 0,
    0.215219, 0.210693, 0.363027, 0, 0.501283, 0, 1.13399, 0.623774, 0, 1.09851,
    1.33313, 0.470441, 0.210965, 0, 0.664178, 0, 0.839686, 0, 0, 0.147834, 0, 0,
    0, 0.58786, 0.490128, 0, 0.905806, 0, 0.932134, 0.424257, 0, 0, 0.860629, 0,
    0, 0, 0.476425, 0, 0.566017, 0.513721, 0.207341, 1.09508, 1.08385, 0,
    0.973787, 0, 0, 0, 0, 0, 0, 1.20698, 0, 0, 0, 1.56135, 1.12369, 0.99588,
    0.459803, 0, 0.915854, 0, 0, 0, 0, 0, 0, 2.03206, 0, 0.773264, 0.267228,
    1.55012, 1.202, 1.51611, 0.701202, 0, 0.725088, 0, 0.509069, 0, 0.671349,
    0.581129, 0.343447, 0, 0.107755, 0.611838, 1.4331, 1.55871, 0.015242,
    0.140624, 0.492562, 0.395095, 0.147722, 0, 0.784925, 0, 1.65477, 0.715257,
    0, 0, 0, 0.685024, 0, 1.89505, 1.00037, 0, 0, 0, 0, 0, 1.52659, 0, 0, 0, 0,
    0.618583, 0, 0.11115, 0, 1.37194, 0.630225, 0, 0, 0, 0, 0, 0.0322124, 0, 0,
    0, 0, 0.430834, 0.252786, 0, 0, 0, 0.991297, 1.98451, 0, 0, 0.111511, 0,
    1.05513, 0, 0, 0, 0, 0, 0, 0.290445, 0.412559, 0.0429958, 0.256564, 1.27858,
    0.289948, 0, 1.01693, 0.327141, 0, 0, 0, 0, 0, 1.83508, 0.346248, 0,
    0.961535, 0.790026, 0.552203, 2.13457, 2.19233, 0.333244, 0.316526,
    0.179398, 0, 0, 0, 0, 0, 1.86126, 0, 0.728256, 0.750013, 0.011861, 0.576383,
    3.38891, 1.29273, 0
] * 2

test(
    name="parallel_linking",
    input=Input("input", "TENSOR_FLOAT32",
                "{{ {}, {}, {} }}".format(num_batches, max_time, input_size)),
    fw_weights=Input("fw_weights", "TENSOR_FLOAT32",
                     "{{ {}, {} }}".format(fw_num_units, input_size)),
    fw_recurrent_weights=Input(
        "fw_recurrent_weights", "TENSOR_FLOAT32",
        "{{ {}, {} }}".format(fw_num_units, fw_num_units)),
    fw_bias=Input("fw_bias", "TENSOR_FLOAT32", "{{ {} }}".format(fw_num_units)),
    fw_hidden_state=Input("fw_hidden_state", "TENSOR_FLOAT32",
                          "{{ {}, {} }}".format(num_batches, fw_num_units)),
    bw_weights=Input("bw_weights", "TENSOR_FLOAT32",
                     "{{ {}, {} }}".format(bw_num_units, input_size)),
    bw_recurrent_weights=Input(
        "bw_recurrent_weights", "TENSOR_FLOAT32",
        "{{ {}, {} }}".format(bw_num_units, bw_num_units)),
    bw_bias=Input("bw_bias", "TENSOR_FLOAT32", "{{ {} }}".format(bw_num_units)),
    bw_hidden_state=Input("bw_hidden_state", "TENSOR_FLOAT32",
                          "{{ {}, {} }}".format(num_batches, bw_num_units)),
    aux_input=Input(
        "aux_input", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(num_batches, max_time, input_size)),
    fw_aux_weights=Input("fw_aux_weights", "TENSOR_FLOAT32", "{0}"),
    bw_aux_weights=Input("bw_aux_weights", "TENSOR_FLOAT32", "{0}"),
    fw_output=IgnoredOutput(
        "fw_output", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(num_batches, max_time, fw_num_units)),
    bw_output=Output(
        "bw_output", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(num_batches, max_time, bw_num_units)),
    activation=1,
    time_major=0,
    merge_outputs=0,
    input_data=[0] * len(input_data),
    fw_weights_data=[0] * fw_num_units * input_size,
    fw_recurrent_weights_data=recurrent_weights_data,
    fw_bias_data=bias_data,
    fw_hidden_state_data=[0] * num_batches * fw_num_units,
    bw_weights_data=weights_data,
    bw_recurrent_weights_data=recurrent_weights_data,
    bw_bias_data=bias_data,
    bw_hidden_state_data=[0] * num_batches * bw_num_units,
    aux_input_data=input_data,
    fw_aux_weights_data=[],
    bw_aux_weights_data=[],
    fw_output_data=[0] * len(fw_output_data),
    bw_output_data=bw_output_data,
)

test(
    name="parallel_linking_time_major",
    input=Input("input", "TENSOR_FLOAT32",
                "{{ {}, {}, {} }}".format(max_time, num_batches, input_size)),
    fw_weights=Input("fw_weights", "TENSOR_FLOAT32",
                     "{{ {}, {} }}".format(fw_num_units, input_size)),
    fw_recurrent_weights=Input(
        "fw_recurrent_weights", "TENSOR_FLOAT32",
        "{{ {}, {} }}".format(fw_num_units, fw_num_units)),
    fw_bias=Input("fw_bias", "TENSOR_FLOAT32", "{{ {} }}".format(fw_num_units)),
    fw_hidden_state=Input("fw_hidden_state", "TENSOR_FLOAT32",
                          "{{ {}, {} }}".format(num_batches, fw_num_units)),
    bw_weights=Input("bw_weights", "TENSOR_FLOAT32",
                     "{{ {}, {} }}".format(bw_num_units, input_size)),
    bw_recurrent_weights=Input(
        "bw_recurrent_weights", "TENSOR_FLOAT32",
        "{{ {}, {} }}".format(bw_num_units, bw_num_units)),
    bw_bias=Input("bw_bias", "TENSOR_FLOAT32", "{{ {} }}".format(bw_num_units)),
    bw_hidden_state=Input("bw_hidden_state", "TENSOR_FLOAT32",
                          "{{ {}, {} }}".format(num_batches, bw_num_units)),
    aux_input=Input(
        "aux_input", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(max_time, num_batches, input_size)),
    fw_aux_weights=Input("fw_aux_weights", "TENSOR_FLOAT32", "{0}"),
    bw_aux_weights=Input("bw_aux_weights", "TENSOR_FLOAT32", "{0}"),
    fw_output=IgnoredOutput(
        "fw_output", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(max_time, num_batches, fw_num_units)),
    bw_output=Output(
        "bw_output", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(max_time, num_batches, bw_num_units)),
    activation=1,
    time_major=1,
    merge_outputs=0,
    input_data=[0] * len(input_data),
    fw_weights_data=[0] * len(weights_data),
    fw_recurrent_weights_data=recurrent_weights_data,
    fw_bias_data=bias_data,
    fw_hidden_state_data=[0] * num_batches * fw_num_units,
    bw_weights_data=weights_data,
    bw_recurrent_weights_data=recurrent_weights_data,
    bw_bias_data=bias_data,
    bw_hidden_state_data=[0] * num_batches * bw_num_units,
    aux_input_data=convert_to_time_major(input_data,
                                         [num_batches, max_time, input_size]),
    fw_aux_weights_data=[],
    bw_aux_weights_data=[],
    fw_output_data=convert_to_time_major(fw_output_data,
                                         [num_batches, max_time, fw_num_units]),
    bw_output_data=convert_to_time_major(bw_output_data,
                                         [num_batches, max_time, bw_num_units]),
)

test(
    name="parallel_linking_time_major_merge_outputs",
    input=Input("input", "TENSOR_FLOAT32",
                "{{ {}, {}, {} }}".format(max_time, num_batches, input_size)),
    fw_weights=Input("fw_weights", "TENSOR_FLOAT32",
                     "{{ {}, {} }}".format(fw_num_units, input_size)),
    fw_recurrent_weights=Input(
        "fw_recurrent_weights", "TENSOR_FLOAT32",
        "{{ {}, {} }}".format(fw_num_units, fw_num_units)),
    fw_bias=Input("fw_bias", "TENSOR_FLOAT32", "{{ {} }}".format(fw_num_units)),
    fw_hidden_state=Input("fw_hidden_state", "TENSOR_FLOAT32",
                          "{{ {}, {} }}".format(num_batches, fw_num_units)),
    bw_weights=Input("bw_weights", "TENSOR_FLOAT32",
                     "{{ {}, {} }}".format(bw_num_units, input_size)),
    bw_recurrent_weights=Input(
        "bw_recurrent_weights", "TENSOR_FLOAT32",
        "{{ {}, {} }}".format(bw_num_units, bw_num_units)),
    bw_bias=Input("bw_bias", "TENSOR_FLOAT32", "{{ {} }}".format(bw_num_units)),
    bw_hidden_state=Input("bw_hidden_state", "TENSOR_FLOAT32",
                          "{{ {}, {} }}".format(num_batches, bw_num_units)),
    aux_input=Input(
        "aux_input", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(max_time, num_batches, input_size)),
    fw_aux_weights=Input("fw_aux_weights", "TENSOR_FLOAT32", "{0}"),
    bw_aux_weights=Input("bw_aux_weights", "TENSOR_FLOAT32", "{0}"),
    fw_output=Output(
        "fw_output", "TENSOR_FLOAT32",
        "{{ {}, {}, {} }}".format(max_time, num_batches,
                                  fw_num_units + bw_num_units)),
    bw_output=None,
    activation=1,
    time_major=1,
    merge_outputs=1,
    input_data=convert_to_time_major(input_data,
                                     [num_batches, max_time, input_size]),
    fw_weights_data=weights_data,
    fw_recurrent_weights_data=recurrent_weights_data,
    fw_bias_data=bias_data,
    fw_hidden_state_data=[0] * num_batches * fw_num_units,
    bw_weights_data=weights_data,
    bw_recurrent_weights_data=recurrent_weights_data,
    bw_bias_data=bias_data,
    bw_hidden_state_data=[0] * num_batches * bw_num_units,
    aux_input_data=convert_to_time_major(input_data,
                                         [num_batches, max_time, input_size]),
    fw_aux_weights_data=[],
    bw_aux_weights_data=[],
    fw_output_data=merge_outputs(
        convert_to_time_major(fw_output_data,
                              [num_batches, max_time, fw_num_units]),
        [max_time, num_batches, fw_num_units],
        convert_to_time_major(bw_output_data,
                              [num_batches, max_time, bw_num_units]),
        [max_time, num_batches, bw_num_units],
    ),
    bw_output_data=None,
)