# coding=utf-8
# Copyright (c) 2020, NVIDIA CORPORATION.  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.

"""For backward compatibility, we need the class definitions to deserialize."""

class LossScaler:
    def __init__(self, scale=1):
        self.cur_scale = scale

class DynamicLossScaler:
    def __init__(self,
                 init_scale=2**32,
                 scale_factor=2.,
                 scale_window=1000,
                 min_scale=1,
                 delayed_shift=1,
                 consecutive_hysteresis=False):
        self.cur_scale = init_scale
        self.cur_iter = 0
        self.last_overflow_iter = -1
        self.scale_factor = scale_factor
        self.scale_window = scale_window
        self.min_scale = min_scale
        self.delayed_shift = delayed_shift
        self.cur_hysteresis = delayed_shift
        self.consecutive_hysteresis = consecutive_hysteresis