"""Gradients for XLA ops."""
# Copyright 2018 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.
# ==============================================================================

from tensorflow.python.framework import ops


@ops.RegisterGradient("XlaClusterOutput")
def _XlaClusterOutputGrad(_, grad):
  del grad  # unused
  raise RuntimeError("Gradient computation of graph in xla.compile() is "
                     "prohibited because it can cause performance degradation."
                     "Please move gradient computation inside xla.compile().")