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

245 lines
9.8 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 Yurii Shyrma (iuriish@yahoo.com), created on 19.04.2018
// @author raver119@gmail.com
//
#include <ops/declarable/helpers/activations.h>
#include <helpers/ShapeUtils.h>
#include <numeric>
#include <helpers/ConstantTadHelper.h>
#include <execution/Threads.h>
namespace sd {
namespace ops {
namespace helpers {
///////////////////////////////////////////////////////////////////
template <typename T>
void static _softMaxDerivForVector(sd::LaunchContext * context, const void *input, const Nd4jLong *inShapeInfo, void *output) {
const T* inBuff = reinterpret_cast<const T *>(input);
T* outBuff = reinterpret_cast<T *>(output);
T max = -DataTypeUtils::max<T>();
T sum = 0.;
int length = shape::length(inShapeInfo);
for (int i = 0; i < length; i++) {
const Nd4jLong offset = shape::getIndexOffset(i, inShapeInfo);
max = sd::math::nd4j_max<T>(max, inBuff[offset]);
}
for (int i = 0; i < length; i++) {
const Nd4jLong offset = shape::getIndexOffset(i, inShapeInfo);
outBuff[offset] = sd::math::nd4j_exp<T, T>(inBuff[offset] - max);
sum += outBuff[offset];
}
for (int i = 0; i < length; i++) {
const Nd4jLong offset = shape::getIndexOffset(i, inShapeInfo);
outBuff[offset] /= sum;
outBuff[offset] *= (1.f - outBuff[offset]); // derivative
}
}
///////////////////////////////////////////////////////////////////
void softmaxDerivative(sd::LaunchContext * context, const NDArray& input, NDArray& output, const int dimension) {
const int rank = input.rankOf();
int temp;
if(shape::isCommonVector(input.shapeInfo(), temp)) {
BUILD_SINGLE_SELECTOR(input.dataType(), _softMaxDerivForVector, (context, input.buffer(), input.shapeInfo(), output.buffer()), FLOAT_TYPES);
}
else {
auto maxAlongDim = const_cast<NDArray&>(input).reduceAlongDimension(reduce::Max, {dimension}, true);
(input - maxAlongDim).applyTransform(transform::Exp, output); // output contains exponents temporarily
auto sumAlongDim = output.reduceAlongDimension(reduce::Sum, {dimension}, true);
output /= sumAlongDim;
output *= (1.f - output); // derivative
}
}
///////////////////////////////////////////////////////////////////
template <typename T>
void logSoftMaxForVector_(void const* input, Nd4jLong const* inShapeInfo, void *output, Nd4jLong const* outShapeInfo) {
auto inBuff = reinterpret_cast<T const*>(input);
auto outBuff = reinterpret_cast<T *>(output);
T max = -DataTypeUtils::max<T>();
T sum = 0;
auto inEWS = shape::elementWiseStride(inShapeInfo);
auto length = shape::length(inShapeInfo);
if (inEWS == 1) {
for (Nd4jLong i = 0; i < length; i++)
max = sd::math::nd4j_max<T>(max, inBuff[i]);
PRAGMA_OMP_SIMD_SUM(sum)
for (Nd4jLong i = 0; i < length; i++) {
outBuff[i] = sd::math::nd4j_exp<T,T>(inBuff[i] - max);
sum += outBuff[i];
}
PRAGMA_OMP_SIMD
for (Nd4jLong i = 0; i < length; i++) {
outBuff[i] /= sum;
outBuff[i] = sd::math::nd4j_log<T,T>(outBuff[i]);
}
}
else if (inEWS > 1) {
PRAGMA_OMP_SIMD_MAX(max)
for (Nd4jLong i = 0; i < length; i++)
max = sd::math::nd4j_max<T>(max, inBuff[i * inEWS]);
PRAGMA_OMP_SIMD_SUM(sum)
for (Nd4jLong i = 0; i < length; i++) {
outBuff[i * inEWS] = sd::math::nd4j_exp<T,T>(inBuff[i * inEWS] - max);
sum += outBuff[i * inEWS];
}
PRAGMA_OMP_SIMD
for (Nd4jLong i = 0; i < length; i++) {
outBuff[i * inEWS] /= sum;
outBuff[i * inEWS] = sd::math::nd4j_log<T, T>(outBuff[i * inEWS]);
}
}
}
///////////////////////////////////////////////////////////////////
void logSoftMaxForVector(sd::LaunchContext* context, const NDArray& input, NDArray& output) {
if(!input.isVector() || !output.isVector())
throw std::runtime_error("ops::helpers::logSoftMaxForVector function input and output arrays must be vectors !");
auto xType = input.dataType();
BUILD_SINGLE_SELECTOR(xType, logSoftMaxForVector_, (input.buffer(), input.shapeInfo(), output.buffer(), output.shapeInfo()), FLOAT_TYPES);
}
//////////////////////////////////////////////////////////////////////////
void prelu(sd::LaunchContext * context, const NDArray& input, const NDArray& alpha, NDArray& output) {
const Nd4jLong inputLen = input.lengthOf();
const Nd4jLong* inputShapeInfo = input.shapeInfo();
const Nd4jLong* alphaShapeInfo = alpha.shapeInfo();
auto func = PRAGMA_THREADS_FOR {
for (auto i = start; i < stop; i++) {
// FIXME: double!
double x = input.e<double>(i);
if (x < 0.0) {
// FIXME: double
output.p(i, (x * alpha.e<double>(shape::subArrayIndex(i, inputShapeInfo, alphaShapeInfo))));
} else
output.p(i, x);
}
};
samediff::Threads::parallel_for(func, 0, inputLen);
}
//////////////////////////////////////////////////////////////////////////
void preluBP(sd::LaunchContext * context, const NDArray& input, const NDArray& alpha, const NDArray& dLdO, NDArray& dLdI, NDArray& dLdA) {
const Nd4jLong inputLen = input.lengthOf();
const Nd4jLong* inputShapeInfo = input.shapeInfo();
const Nd4jLong* alphaShapeInfo = alpha.shapeInfo();
dLdA.assign(0.0f);
for(Nd4jLong i = 0; i < inputLen; ++i) {
// FIXME: double
double x = input.e<double>(i);
double grO = dLdO.e<double>(i);
if(x < 0.0) {
Nd4jLong alphaInd = shape::subArrayIndex(i, inputShapeInfo, alphaShapeInfo);
dLdI.p(i, grO * alpha.e<double>(alphaInd));
double prevVal = dLdA.e<double>(alphaInd);
prevVal += (grO * x);
dLdA.p(alphaInd, prevVal);
}
else
dLdI.p(i, grO);
}
}
bool checkAlphaShapeLen(std::vector<Nd4jLong> const& expectedShape, Nd4jLong shapeLen) {
Nd4jLong expectedAlphaLen = std::accumulate(expectedShape.cbegin(), expectedShape.cend(), 1, std::multiplies<Nd4jLong>());
return expectedAlphaLen == shapeLen;
}
template <typename T>
static void thresholdRelu_(NDArray const& input, double threshold, NDArray& output) {
auto routine = LAMBDA_T(_x, threshold) {
return _x > (T)threshold? _x: (T)0.f;
};
const_cast<NDArray&>(input).applyLambda<T>(routine, output);
}
void thresholdRelu(sd::LaunchContext * context, NDArray const& input, double threshold, NDArray& output) {
BUILD_SINGLE_SELECTOR(input.dataType(), thresholdRelu_, (input, threshold, output), FLOAT_TYPES);
}
template <typename T>
static void thresholdReluDerivative_(sd::LaunchContext * context, NDArray* input, double theta, NDArray* dLdO, NDArray* output) {
auto derivative = LAMBDA_TT(_x, grO, theta) {if (_x > theta) return grO; else return static_cast<T>(0); };
input->applyPairwiseLambda<T>(*dLdO, derivative, *output);
}
void thresholdReluDerivative(sd::LaunchContext * context, NDArray* input, double threshold, NDArray* dLdO, NDArray* output) {
BUILD_SINGLE_SELECTOR(input->dataType(), thresholdReluDerivative_, (context, input, threshold, dLdO, output), FLOAT_TYPES);
}
///////////////////////////////////////////////////////////////////
void logSoftmax(sd::LaunchContext * context, const NDArray& input, NDArray& output, const int dimension) {
const int rank = input.rankOf();
if(input.isVector()) {
if(rank == 1 || input.sizeAt(dimension) != 1) {
BUILD_SINGLE_SELECTOR(input.dataType(), logSoftMaxForVector_, (input.buffer(), input.shapeInfo(), output.buffer(), output.shapeInfo()), FLOAT_TYPES);
}
else
output = 0.;
}
else {
auto maxAlongDim = const_cast<NDArray&>(input).reduceAlongDimension(reduce::Max, {dimension}, true);
(input - maxAlongDim).applyTransform(transform::Exp, output); // output contains exponents temporarily
auto sumAlongDim = output.reduceAlongDimension(reduce::Sum, {dimension}, true);
output /= sumAlongDim;
output.applyTransform(transform::Log, output);
}
}
BUILD_SINGLE_TEMPLATE(template void thresholdReluDerivative_, (sd::LaunchContext * context, NDArray* input, double threshold, NDArray* dLdO, NDArray* output), FLOAT_TYPES);
BUILD_SINGLE_TEMPLATE(template void logSoftMaxForVector_, (void const* input, Nd4jLong const* inShapeInfo, void *output, Nd4jLong const* outShapeInfo), FLOAT_TYPES);
BUILD_SINGLE_TEMPLATE(template void _softMaxDerivForVector, (sd::LaunchContext * context, const void *input, const Nd4jLong *inShapeInfo, void *output), FLOAT_TYPES);
}
}
}