cavis/libnd4j/include/ops/declarable/helpers/cpu/fake_quantization.cpp

122 lines
5.1 KiB
C++

/*******************************************************************************
* Copyright (c) 2015-2018 Skymind, Inc.
*
* This program and the accompanying materials are made available under the
* terms of the Apache License, Version 2.0 which is available at
* https://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.
*
* SPDX-License-Identifier: Apache-2.0
******************************************************************************/
//
// @author sgazeos@gmail.com
//
#include <ops/declarable/helpers/fake_quantization.h>
#include <NDArrayFactory.h>
namespace nd4j {
namespace ops {
namespace helpers {
template <typename T>
static void Nudge(T min, T max, T quant_min, T quant_max, T* scale, T* nudged_min, T* nudged_max) {
*scale = (max - min) / (quant_max - quant_min);
auto zero_point_from_min = quant_min - min / *scale;
uint16_t const nudged_zero_point = [zero_point_from_min, quant_min, quant_max] {
if (zero_point_from_min < quant_min) {
return static_cast<uint16_t>(quant_min);
}
if (zero_point_from_min > quant_max) {
return static_cast<uint16_t>(quant_max);
}
return nd4j::math::nd4j_round<T,uint16_t>(zero_point_from_min);
}();
*nudged_min = (quant_min - nudged_zero_point) * (*scale);
*nudged_max = (quant_max - nudged_zero_point) * (*scale);
}
template <typename T>
void fakeQuantWithMinMaxVarsPerChannel_(NDArray* input, NDArray* min, NDArray* max, int numBits, bool narrowed, NDArray* output) {
int lowIntBound = narrowed ? 1 : 0;
int upperIntBound = 1 << numBits - 1;
const float quant_min_float = static_cast<float>(lowIntBound);
const float quant_max_float = static_cast<float>(upperIntBound);
// auto scaleTensor(*input); // = NDArrayFactory::create(input->ordering(), input->getShapeAsVector(), input->getWorkspace());
auto clamped(*input); // = NDArrayFactory::create(input->ordering(), input->getShapeAsVector(), input->getWorkspace());
for (auto i = 0; i < min->lengthOf(); i++) {
T scale, nudged_min, nudged_max;
Nudge<T>(min->t<T>(i), max->t<T>(i), quant_min_float, quant_max_float, &scale, &nudged_min, &nudged_max);
auto wiseMinMax = LAMBDA_T(x, nudged_min, nudged_max) {
if (x < nudged_min) {
return nudged_min;
}
else if (x > nudged_max)
return nudged_max;
return x;
};
// scaleTensor.assign(scale);
input->applyLambda<T>(wiseMinMax, &clamped);
clamped -= nudged_min;
// auto nudgedScale = scale;
clamped /= scale;
clamped += T(0.5f);
clamped.applyTransform(transform::Floor, output, nullptr);
(*output) *= scale;
(*output) += nudged_min;
}
}
template <typename T>
static void WiseMinMax(NDArray* input, T min, T max, NDArray* output) {
auto wiseMinMax = LAMBDA_T(x, min, max) {
if (x < min) {
return min;
}
else if (x > max)
return max;
return x;
};
input->applyLambda<T>(wiseMinMax, output);
}
template <typename T>
void fakeQuantWithMinMaxVars_(NDArray* input, NDArray* min, NDArray* max, int numBits, bool narrowed, NDArray* output) {
int lowIntBound = narrowed ? 1 : 0;
int upperIntBound = 1 << numBits - 1;
const float quant_min_float = static_cast<float>(lowIntBound);
const float quant_max_float = static_cast<float>(upperIntBound);
T nudged_min, nudged_max, scale;
Nudge<T>(min->t<T>(0), max->t<T>(0), quant_min_float, quant_max_float, &scale, &nudged_min, &nudged_max);
WiseMinMax<T>(input, nudged_min, nudged_max, output);
*output -= nudged_min;
(*output) /= scale;
(*output) += T(0.5f);
output->applyTransform(transform::Floor, nullptr, nullptr);
(*output) *= scale;
(*output) += nudged_min;
}
void fakeQuantWithMinMaxVars(NDArray* input, NDArray* min, NDArray* max, int numBits, bool narrowed, NDArray* output) {
BUILD_SINGLE_SELECTOR(input->dataType(), fakeQuantWithMinMaxVars_, (input, min, max, numBits, narrowed, output), FLOAT_TYPES);
}
void fakeQuantWithMinMaxVarsPerChannel(NDArray* input, NDArray* min, NDArray* max, int numBits, bool narrowed, NDArray* output) {
BUILD_SINGLE_SELECTOR(input->dataType(), fakeQuantWithMinMaxVarsPerChannel_, (input, min, max, numBits, narrowed, output), FLOAT_TYPES);
}
BUILD_SINGLE_TEMPLATE(template void fakeQuantWithMinMaxVars_, (NDArray* input, NDArray* min, NDArray* max, int numBits, bool narrowed, NDArray* output), FLOAT_TYPES);
}
}
}