blob: d319ea09fb9d27bb5c876767fb5fd2c37c05e884 [file] [log] [blame]
#include "caffe2/core/context_gpu.h"
#include "caffe2/operators/perplexity_op.h"
#include "caffe2/utils/math.h"
#include <thrust/device_vector.h>
#include <thrust/transform_reduce.h>
#include <thrust/system/cuda/execution_policy.h>
namespace caffe2 {
struct perplexity_function
{
perplexity_function(float p) : pow(p) {}
__host__ __device__ float operator()(float x) const
{
return powf(1.0f/x, pow);
}
float pow;
};
template <>
bool PerplexityOp<float, CUDAContext>::RunOnDevice() {
auto& X = Input(0);
TORCH_DCHECK_EQ(X.dim(), 1);
int N = X.dim32(0);
auto* Y = Output(0, vector<int64_t>(), at::dtype<float>());
float* Ydata = Y->template mutable_data<float>();
const float* Xdata = X.data<float>();
float perplexity = thrust::transform_reduce(
#if THRUST_VERSION >= 100800
thrust::cuda::par.on(context_.cuda_stream()),
#endif // THRUST_VERSION >= 100800
Xdata, Xdata + N,
perplexity_function(1.0f/N),
1.0f,
thrust::multiplies<float>());
math::Set<float, CUDAContext>(1, perplexity, Ydata, &context_);
return true;
}
REGISTER_CUDA_OPERATOR(Perplexity, PerplexityOp<float, CUDAContext>);
} // namespace caffe2