==== Cuda Version: Attempt Two ====
In progressGives a run time error "invalid argument".Logical error still persists. <pre> # include <cmath> // This library enable the use of sqrt. # include <iostream> # include <ctime> #include<iomanip> #include<cstdlib> # include <cuda_runtime.h> //#include <times.h> using namespace std; inline clock_t getMilliSecs() { return clock() / (CLOCKS_PER_SEC / 1000); } __global__ void primegen(bool prime, int number2,int x,int *primes_d,int index) { int c = 0; int idx = blockIdx.x * blockDim.x + threadIdx.x; // number2 =(int) floor (sqrt (x)); // cout<< "value of idx" << idx <<endl; /* if( !(x!=idx && x%idx == 0 ) ) { primes_d[c] = x; c++; } */ primes_d[idx] = 666; c++; } /*for (int i = 1; i <= x; i++) { for ( int j = 2; j <= number2; j++) { if ( i!=j && i % j == 0 ) { prime = false; break; } } if (prime) { primes_d[c]=i; c += 1; } prime = true; } */ void primenum(long double); // Prototype... int main() { long double x = 0; cout<<"\n This program will generate all prime numbers up to the"<<"\n number you have entered below...\n"; cout<<"\n Please enter a number: "; cin>> x; cout<<"\n Here are all the prime numbers up to "<<x<<".\n"; primenum(x); //function invocation... //cout<<endl<<"\nThere are "<<c //<<" prime numbers less than or equal to "<<x<<".\n\n"; return 0; } // This function will determine the primenumbers up to num. void primenum(long double x) { int n = x; int d; bool prime = true; //struct tms start_time, stop_time; int number2; // number2 =(int) floor (sqrt (x)); clock_t start = getMilliSecs(); cudaDeviceProp prop; cudaGetDevice(&d); cudaGetDeviceProperties(&prop, d); int nThreads = prop.maxThreadsDim[0]; int n_max = nThreads * prop.maxGridSize[0]; if ( n> n_max) { n = n_max; cout << "n reduced to " << n << endl; } //Array to hold generated primes on host int *primes_h = new int[(int)x]; //Device array to hold the primes on the device int *primes_d = new int[(int)x]; //allocate device memory and initialize device memory cudaMalloc((void**)&primes_d, (int)x * sizeof(int)); // cudaMalloc((void**)&c_d, sizeof(int)); cudaMemset(&primes_d,0,x * sizeof(int)); primes_h[0] = 666; //error checking cudaError_t error ; for(int i=0; i<(int)x ; i++){ //if(primes_h[i]>=2 && primes_h[i]<=(int)x){ cout<<"BEFORE:"<<primes_h[i]<<endl; //} } //Kernal goes here //for ( int i=2; i<= x; i++) //{ int i=10; number2 =(int) floor (sqrt ((long double)i)); // primegen<<<1, x>>>(prime,number2,(int)i,primes_d,666); // primegen<<<1, x>>>(prime,number2,(int)i,primes_d,666); cudaDeviceSynchronize(); //} // extract error code from the kernel's execution error = cudaGetLastError(); if (error != cudaSuccess) { cout << cudaGetErrorString(error) << endl; } //copy the array holding primes from device to host error =cudaMemcpy(primes_h, primes_d, ((int)x) * sizeof(int), cudaMemcpyDeviceToHost); if (error != cudaSuccess) { cout << cudaGetErrorString(error) << endl; } // cudaMemcpy(c_h, c_d, sizeof(int), cudaMemcpyDeviceToHost); //display the primes for(int i=0; i<(int)x ; i++){ //if(primes_h[i]>=2 && primes_h[i]<=(int)x){ cout<<primes_h[i]<<endl; //} } cout << "Elapsed time: " << (getMilliSecs() - start) << "ms" << endl; // cout<< "time: "<< (stop_s-start_s)/double(CLOCKS_PER_SEC)<<endl; //free allocated memory delete [] primes_h; cudaFree(primes_d); getchar(); } </pre>
