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#include <iostream>
#include <math.h>
#include "sleefinline_cuda.h"
// Based on the tutorial code at https://developer.nvidia.com/blog/even-easier-introduction-cuda/
__global__ void pow_gpu(int n, double *r, double *x, double *y)
{
int index = threadIdx.x, stride = blockDim.x;
for (int i = index; i < n; i += stride)
r[i] = Sleef_powd1_u10cuda(x[i], y[i]);
}
int main(void)
{
int N = 1 << 20;
double *r, *x, *y;
cudaMallocManaged(&r, N*sizeof(double));
cudaMallocManaged(&x, N*sizeof(double));
cudaMallocManaged(&y, N*sizeof(double));
for (int i = 0; i < N; i++) {
r[i] = 0.0;
x[i] = 1.00001;
y[i] = i;
}
pow_gpu<<<1, 256>>>(N, r, x, y);
cudaDeviceSynchronize();
double maxError = 0.0f;
for (int i = 0; i < N; i++)
maxError = fmax(maxError, fabs(r[i]-pow(x[i], y[i])));
std::cout << "Max error: " << maxError << std::endl;
cudaFree(y);
cudaFree(x);
cudaFree(r);
return 0;
}
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