add Gather operator

include/aidge/backend/cpu/operator/GatherImpl.hpp

+/********************************************************************************
+ * Copyright (c) 2023 CEA-List
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ ********************************************************************************/
+
+#ifndef AIDGE_CPU_OPERATOR_GATHERIMPL_H_
+#define AIDGE_CPU_OPERATOR_GATHERIMPL_H_
+
+#include "aidge/backend/OperatorImpl.hpp"
+#include "aidge/operator/Gather.hpp"
+#include "aidge/utils/Registrar.hpp"
+#include "aidge/utils/Types.h"
+#include <memory>
+#include <vector>
+
+namespace Aidge {
+// class Gather_Op;
+
+// compute kernel registry for forward and backward
+class GatherImplForward_cpu
+    : public Registrable<GatherImplForward_cpu, std::tuple<DataType, DataType>, void(const int, const std::vector<DimSize_t>, const std::vector<DimSize_t>, const void*, const void*, void*)> {
+};
+class GatherImplBackward_cpu
+    : public Registrable<GatherImplBackward_cpu, std::tuple<DataType, DataType>, void(const int, const std::vector<DimSize_t>, const std::vector<DimSize_t>, const void*, const void*, void*)> {
+};
+
+class GatherImpl_cpu : public OperatorImpl {
+public:
+    GatherImpl_cpu(const Gather_Op& op) : OperatorImpl(op) {}
+
+    static std::unique_ptr<GatherImpl_cpu> create(const Gather_Op& op) {
+        return std::make_unique<GatherImpl_cpu>(op);
+    }
+
+    NbElts_t getNbRequiredProtected(const IOIndex_t inputIdx) const override final;
+    void forward() override;
+};
+
+namespace {
+static Registrar<Gather_Op> registrarGatherImpl_cpu("cpu", Aidge::GatherImpl_cpu::create);
+}
+}  // namespace Aidge
+
+#endif /* AIDGE_CPU_OPERATOR_GATHERIMPL_H_ */

include/aidge/backend/cpu/operator/GatherImpl_forward_kernels.hpp

+/********************************************************************************
+ * Copyright (c) 2023 CEA-List
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ ********************************************************************************/
+
+#ifndef AIDGE_CPU_OPERATOR_GATHERIMPL_FORWARD_KERNEL_H_
+#define AIDGE_CPU_OPERATOR_GATHERIMPL_FORWARD_KERNEL_H_
+
+#include "aidge/utils/Registrar.hpp"
+#include <cstddef>
+#include <cmath>
+#include "aidge/data/Data.hpp"
+#include "aidge/utils/Types.h"
+
+#include "aidge/backend/cpu/operator/GatherImpl.hpp"
+
+namespace Aidge {
+template <class I, class O>
+void GatherImpl_cpu_forward_kernel(const int& axisIdx_, std::vector<DimSize_t> inputDims, const std::vector<DimSize_t> indicesDims, const void* input_, const void* indexes_, void* output_)
+{
+    const I* input = static_cast<const I*>(input_);
+    const int* indexes = static_cast<const int*>(indexes_);
+    const std::size_t axisIdx = axisIdx_;
+    O* output = static_cast<O*>(output_);
+
+    // Calculate the total number of elements in the input array
+    size_t totalElements = 1;
+    for (size_t dimSize : inputDims) {
+        totalElements *= dimSize;
+    }
+    std::size_t nbElemAfterAxis = 1;
+    std::size_t nbElemBeforeAxis = 1;
+
+    for (size_t d = 0; d < inputDims.size(); ++d) {
+        if( d < axisIdx )
+            nbElemBeforeAxis *= inputDims[d];
+        else if ( d > axisIdx )
+            nbElemAfterAxis *= inputDims[d];
+    }
+
+    for (std::size_t i=0; i<nbElemBeforeAxis; ++i)
+    {
+        for(std::size_t idxRow=0; idxRow<indicesDims[0]; ++idxRow)
+        {
+            for(std::size_t idxCol=0; idxCol<indicesDims[1]; ++idxCol)
+            {
+                std::size_t idx = indexes[indicesDims[1] *  idxRow + idxCol];
+                const I* startPtr = std::next(input, i * nbElemAfterAxis * inputDims[axisIdx] + idx * nbElemAfterAxis);
+                std::copy_n(startPtr, nbElemAfterAxis, output);
+                output += nbElemAfterAxis;
+            }
+        }
+    }
+}
+
+namespace {
+static Registrar<GatherImplForward_cpu> registrarGatherImplForward_cpu_Float32(
+        {DataType::Float32, DataType::Float32}, Aidge::GatherImpl_cpu_forward_kernel<float, float>);
+static Registrar<GatherImplForward_cpu> registrarGatherImplForward_cpu_Int32(
+        {DataType::Int32, DataType::Int32}, Aidge::GatherImpl_cpu_forward_kernel<int, int>);
+static Registrar<GatherImplForward_cpu> registrarGatherImplForward_cpu_Float64(
+        {DataType::Float64, DataType::Float64}, Aidge::GatherImpl_cpu_forward_kernel<double, double>);
+}  // namespace
+}  // namespace Aidge
+
+#endif /* AIDGE_CPU_OPERATOR_GATHERIMPL_FORWARD_KERNEL_H_ */

src/operator/GatherImpl.cpp

+/********************************************************************************
+ * Copyright (c) 2023 CEA-List
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ ********************************************************************************/
+
+#include <cassert>
+#include <chrono>  // std::chrono::milliseconds
+#include <numeric> // std::accumulate
+#include <thread>  // std::this_thread::sleep_for
+#include <vector>
+
+#include "aidge/operator/Gather.hpp"
+#include "aidge/utils/Types.h"
+
+#include "aidge/backend/cpu/operator/GatherImpl.hpp"
+#include "aidge/backend/cpu/operator/GatherImpl_forward_kernels.hpp"
+
+#include <iostream>
+
+Aidge::NbElts_t Aidge::GatherImpl_cpu::getNbRequiredProtected(const Aidge::IOIndex_t /*inputIdx*/) const {
+    // this implementation can be in-place
+    return 0;
+}
+
+void Aidge::GatherImpl_cpu::forward() {
+    assert(mOp.getInput(0) && "missing input #0");
+    assert(mOp.getInput(1) && "missing input #1");
+    assert((mOp.getInput(0)->nbDims() == 2 && mOp.getInput(1)->nbDims() == 2 )&& "only 2D tensors are supported");
+
+    Gather_Op::Attrs attr = dynamic_cast<const Gather_Op&>(mOp).getStaticAttributes();
+    const int& axisIdx = static_cast<const int&>(std::get<0>(attr));
+    assert(mOp.getInput(0)->nbDims() > 1);// > axisIdx && "input dim must be bigger than "+std::to_strint(axisIdx)
+
+    auto kernelFunc = Registrar<GatherImplForward_cpu>::create({
+        mOp.getInput(0)->dataType(),
+        mOp.getOutput(0)->dataType()});
+
+    // Call kernel
+    kernelFunc(axisIdx,
+               mOp.getInput(0)->dims(),
+               mOp.getInput(1)->dims(),
+               mOp.getInput(0)->getImpl()->rawPtr(),
+               mOp.getInput(1)->getImpl()->rawPtr(),
+               mOp.getOutput(0)->getImpl()->rawPtr());
+}

unit_tests/operator/Test_GatherImpl.cpp

+/********************************************************************************
+ * Copyright (c) 2023 CEA-List
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ ********************************************************************************/
+
+#include <catch2/catch_test_macros.hpp>
+
+#include "aidge/data/Tensor.hpp"
+#include "aidge/operator/Gather.hpp"
+
+#include "aidge/backend/cpu.hpp"
+
+#include <memory>
+
+
+using namespace Aidge;
+
+TEST_CASE("[cpu/operator] Gather(forward)") {
+    SECTION("2D Tensor axis 0") {
+        std::shared_ptr<Tensor> input = std::make_shared<Tensor>(Array2D<int,3,3> {
+            {
+                {1, 2, 3},
+                {4, 5, 6},
+                {7, 8, 9}
+            }
+        });
+        std::shared_ptr<Tensor> indexes = std::make_shared<Tensor>(Array2D<int,1,2> {
+            {
+                {1, 2}
+            }
+        });
+        std::shared_ptr<Tensor> expectedOutput = std::make_shared<Tensor>(Array3D<int,1,2,3> {
+            {
+                {
+                    {4, 5, 6},
+                    {7, 8, 9}
+                }
+            }
+        });
+
+        std::shared_ptr<Node> myGather = Gather(0);
+        myGather->getOperator()->setDatatype(DataType::Int32);
+        myGather->getOperator()->setBackend("cpu");
+        myGather->getOperator()->associateInput(0,input);
+        myGather->getOperator()->associateInput(1,indexes);
+        myGather->getOperator()->computeOutputDims();
+        myGather->forward();
+
+        REQUIRE(myGather->getOperator()->output(0).dims() == expectedOutput->dims());
+        REQUIRE(*(myGather->getOperator()->getOutput(0)) == *expectedOutput);
+
+    }
+    SECTION("2D Tensor axis 1") {
+        std::shared_ptr<Tensor> input = std::make_shared<Tensor>(Array2D<int,3,3> {
+            {
+                {1, 2, 3},
+                {4, 5, 6},
+                {7, 8, 9}
+            }
+        });
+        std::shared_ptr<Tensor> indexes = std::make_shared<Tensor>(Array2D<int,1,2> {
+            {
+                {0, 2}
+            }
+        });
+        std::shared_ptr<Tensor> expectedOutput = std::make_shared<Tensor>(Array3D<int,3,1,2> {
+            {
+                {
+                    {1, 3}
+                },
+                {
+                    {4, 6}
+                },
+                {
+                    {7, 9}
+                }
+            }
+        });
+
+        std::shared_ptr<Node> myGather = Gather(1);
+        myGather->getOperator()->setDatatype(DataType::Int32);
+        myGather->getOperator()->setBackend("cpu");
+        myGather->getOperator()->associateInput(0,input);
+        myGather->getOperator()->associateInput(1,indexes);
+        myGather->getOperator()->computeOutputDims();
+        myGather->forward();
+
+        REQUIRE(myGather->getOperator()->output(0).dims() == expectedOutput->dims());
+        REQUIRE(*(myGather->getOperator()->getOutput(0)) == *expectedOutput);
+
+    }
+}
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