Add missing file

gpu_environment.py

@@ -0,0 +1,36 @@
+# coding=utf-8
+# 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.
+
+import tensorflow as tf
+import numpy as np
+
+def float32_variable_storage_getter(getter, name, shape=None, dtype=None,
+                                    initializer=None, regularizer=None,
+                                    trainable=True,
+                                    *args, **kwargs):
+    """Custom variable getter that forces trainable variables to be stored in
+       float32 precision and then casts them to the training precision.
+    """
+    storage_dtype = tf.float32 if trainable else dtype
+    variable = getter(name, shape, dtype=storage_dtype,
+                      initializer=initializer, regularizer=regularizer,
+                      trainable=trainable,
+                      *args, **kwargs)
+    if trainable and dtype != tf.float32:
+        variable = tf.cast(variable, dtype)
+    return variable
+
+def get_custom_getter(compute_type):
+    return float32_variable_storage_getter if compute_type == tf.float16 else None