internal/ceres/cuda_kernels.h

// Ceres Solver - A fast non-linear least squares minimizer
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// http://ceres-solver.org/
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// Author: joydeepb@cs.utexas.edu (Joydeep Biswas)

#ifndef CERES_INTERNAL_CUDA_KERNELS_H_
#define CERES_INTERNAL_CUDA_KERNELS_H_

#include "ceres/internal/config.h"

#ifndef CERES_NO_CUDA

#include "cuda_runtime.h"

namespace ceres::internal {

// Convert an array of double (FP64) values to float (FP32). Both arrays must
// already be on GPU memory.
void CudaFP64ToFP32(const double* input,
                    float* output,
                    const int size,
                    cudaStream_t stream);

// Convert an array of float (FP32) values to double (FP64). Both arrays must
// already be on GPU memory.
void CudaFP32ToFP64(const float* input,
                    double* output,
                    const int size,
                    cudaStream_t stream);

// Set all elements of the array to the FP32 value 0. The array must be in GPU
// memory.
void CudaSetZeroFP32(float* output, const int size, cudaStream_t stream);

// Set all elements of the array to the FP64 value 0. The array must be in GPU
// memory.
void CudaSetZeroFP64(double* output, const int size, cudaStream_t stream);

// Compute x = x + double(y). Input array is float (FP32), output array is
// double (FP64). Both arrays must already be on GPU memory.
void CudaDsxpy(double* x, float* y, const int size, cudaStream_t stream);

// Compute y[i] = y[i] + d[i]^2 x[i]. All arrays must already be on GPU memory.
void CudaDtDxpy(double* y,
                const double* D,
                const double* x,
                const int size,
                cudaStream_t stream);

}  // namespace ceres::internal

#endif  // CERES_NO_CUDA

#endif  // CERES_INTERNAL_CUDA_KERNELS_H_