Files
deeplearning4j--deeplearning4j/libnd4j/include/ops/declarable/helpers/cpu/activations.cpp
T
2026-07-13 12:47:05 +08:00

273 lines
10 KiB
C++

/* ******************************************************************************
*
*
* 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.
*
* See the NOTICE file distributed with this work for additional
* information regarding copyright ownership.
* 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 <execution/Threads.h>
#include <helpers/ConstantTadHelper.h>
#include <helpers/ShapeUtils.h>
#include <ops/declarable/helpers/activations.h>
#include <numeric>
namespace sd {
namespace ops {
namespace helpers {
///////////////////////////////////////////////////////////////////
template <typename T>
void static _softMaxDerivForVector(sd::LaunchContext* context, const void* input, const sd::LongType* inShapeInfo,
void* output) {
const T* inBuff = reinterpret_cast<const T*>(input);
T* outBuff = reinterpret_cast<T*>(output);
T max = -DataTypeUtils::max<T>();
T sum = static_cast<T>(0.);
const sd::LongType length = shape::length(inShapeInfo);
const sd::LongType rank = shape::rank(inShapeInfo);
const sd::LongType* shape = shape::shapeOf(inShapeInfo);
const sd::LongType* stride = shape::stride(inShapeInfo);
LongType coords[SD_MAX_RANK];
LongType offset;
// Find the maximum value in the vector
for (sd::LongType i = 0; i < length; i++) {
INDEX2COORDS(i, rank, shape, coords);
COORDS2INDEX(rank, stride, coords, offset);
max = sd::math::sd_max<T>(max, inBuff[offset]);
}
// Calculate exponentials and sum
for (sd::LongType i = 0; i < length; i++) {
INDEX2COORDS(i, rank, shape, coords);
COORDS2INDEX(rank, stride, coords, offset);
outBuff[offset] = sd::math::sd_exp<T, T>(inBuff[offset] - max);
sum += outBuff[offset];
}
// Compute softmax derivatives
for (sd::LongType i = 0; i < length; i++) {
INDEX2COORDS(i, rank, shape, coords);
COORDS2INDEX(rank, stride, coords, offset);
outBuff[offset] /= sum;
outBuff[offset] *= (1.f - outBuff[offset]); // derivative
}
}
///////////////////////////////////////////////////////////////////
void softmaxDerivative(sd::LaunchContext* context, NDArray& input, NDArray& output, const int dimension) {
const int rank = input.rankOf();
sd::LongType temp;
if (shape::isCommonVector(input.shapeInfo(), temp)) {
BUILD_SINGLE_SELECTOR(input.dataType(), _softMaxDerivForVector,
(context, input.buffer(), input.shapeInfo(), output.buffer()), SD_FLOAT_TYPES);
} else {
std::vector<sd::LongType> dimVec = {dimension};
auto maxAlongDim = const_cast<NDArray&>(input).reduceAlongDimension(reduce::Max, &dimVec, true);
auto minus = (input - *maxAlongDim);
minus->applyTransform(transform::Exp, &output); // output contains exponents temporarily
auto sumAlongDim = output.reduceAlongDimension(reduce::Sum, &dimVec, true);
output /= *sumAlongDim;
auto oneMinus = (1.f - output);
output *= *oneMinus; // derivative
delete sumAlongDim;
delete minus;
delete oneMinus;
}
}
///////////////////////////////////////////////////////////////////
template <typename T>
void logSoftMaxForVector_(void const* input, sd::LongType const* inShapeInfo, void* output,
sd::LongType const* outShapeInfo) {
auto inBuff = reinterpret_cast<T const*>(input);
auto outBuff = reinterpret_cast<T*>(output);
T max = -DataTypeUtils::max<T>();
T sum = static_cast<T>(0);
auto length = shape::length(inShapeInfo);
sd::LongType inRank = shape::rank(inShapeInfo);
sd::LongType *inShape = shape::shapeOf(inShapeInfo);
sd::LongType *inStrides = shape::stride(inShapeInfo);
sd::LongType *outShape = shape::shapeOf(outShapeInfo);
sd::LongType *outStrides = shape::stride(outShapeInfo);
sd::LongType outRank = shape::rank(outShapeInfo);
sd::LongType inIndices[length];
sd::LongType outIndices[length];
PRAGMA_OMP_SIMD
for (sd::LongType i2 = 0; i2 < length; i2++) {
LongType coords[SD_MAX_RANK];
sd::LongType idx2;
INDEX2COORDS(i2,inRank, inShape, coords);
COORDS2INDEX(inRank, inStrides, coords, idx2);
max = sd::math::sd_max<T,T>(max, inBuff[idx2]);
inIndices[i2] = idx2;
}
PRAGMA_OMP_SIMD
for (sd::LongType i2 = 0; i2 < length; i2++) {
LongType coords[SD_MAX_RANK];
sd::LongType idx2;
INDEX2COORDS(i2,outRank, outShape, coords);
COORDS2INDEX(outRank, outStrides, coords, idx2);
outBuff[idx2] = sd::math::sd_exp<T, T>(inBuff[inIndices[i2]] - max);
sum += outBuff[idx2];
}
PRAGMA_OMP_SIMD
for (sd::LongType i = 0; i < length; i++) {
outBuff[outIndices[i]] /= sum;
outBuff[outIndices[i]] = sd::math::sd_log<T, T>(outBuff[outIndices[i]]);
}
}
///////////////////////////////////////////////////////////////////
void logSoftMaxForVector(sd::LaunchContext* context, NDArray& input, NDArray& output) {
if (!input.isVector() || !output.isVector())
THROW_EXCEPTION("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()), SD_FLOAT_TYPES);
}
//////////////////////////////////////////////////////////////////////////
void prelu(LaunchContext* context, NDArray* input, NDArray* alpha, NDArray* output) {
const sd::LongType inputLen = input->lengthOf();
const sd::LongType* inputShapeInfo = input->shapeInfo();
const sd::LongType* alphaShapeInfo = alpha->shapeInfo();
auto func = PRAGMA_THREADS_FOR {
for (sd::LongType 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(LaunchContext* context, NDArray* input, NDArray* alpha, NDArray* dLdO, NDArray* dLdI,
NDArray* dLdA) {
const sd::LongType inputLen = input->lengthOf();
const sd::LongType* inputShapeInfo = input->shapeInfo();
const sd::LongType* alphaShapeInfo = alpha->shapeInfo();
float zero = 0.f;
dLdA->assign(zero);
for (sd::LongType i = 0; i < inputLen; ++i) {
// FIXME: double
double x = input->e<double>(i);
double grO = dLdO->isScalar() ? dLdO->e<double>(0) : dLdO->e<double>(i);
if (x < 0.0) {
sd::LongType 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<sd::LongType> const& expectedShape, sd::LongType shapeLen) {
sd::LongType expectedAlphaLen =
std::accumulate(expectedShape.cbegin(), expectedShape.cend(), 1, std::multiplies<sd::LongType>());
return expectedAlphaLen == shapeLen;
}
template <typename T>
static void thresholdRelu_(NDArray *input, double threshold, NDArray* output) {
auto routine = LAMBDA_T(_x, threshold) { return _x > (T)threshold ? _x : (T)0.f; });
input->applyLambda<T>(routine, output);
}
void thresholdRelu(LaunchContext* context, NDArray* input, double threshold, NDArray* output) {
BUILD_SINGLE_SELECTOR(input->dataType(), thresholdRelu_, (input, threshold, output), SD_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),
SD_FLOAT_TYPES);
}
///////////////////////////////////////////////////////////////////
void logSoftmax(LaunchContext* context, 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()), SD_FLOAT_TYPES);
} else
*output = 0.;
} else {
std::vector<sd::LongType> dimVector = {dimension};
auto maxAlongDim = input->reduceAlongDimension(reduce::Max, &dimVector, true);
auto maxMinusDim = *input - *maxAlongDim;
maxMinusDim->applyTransform(transform::Exp, output); // output contains exponents temporarily
auto sumAlongDim = output->reduceAlongDimension(reduce::Sum, &dimVector, true);
*output /= *sumAlongDim;
output->applyTransform(transform::Log, output);
delete maxAlongDim;
delete maxMinusDim;
delete sumAlongDim;
}
}
BUILD_SINGLE_TEMPLATE( void thresholdReluDerivative_,
(sd::LaunchContext * context, NDArray* input, double threshold, NDArray* dLdO, NDArray* output),
SD_FLOAT_TYPES);
BUILD_SINGLE_TEMPLATE( void logSoftMaxForVector_,
(void const* input, sd::LongType const* inShapeInfo, void* output,
sd::LongType const* outShapeInfo),
SD_FLOAT_TYPES);
BUILD_SINGLE_TEMPLATE( void _softMaxDerivForVector,
(sd::LaunchContext * context, const void* input, const sd::LongType* inShapeInfo, void* output),
SD_FLOAT_TYPES);
} // namespace helpers
} // namespace ops
} // namespace sd