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POHow do pass data to a shared variable in CUDA?
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copied!<p>I have a kernel which passes 3 arrays, the first array d_A1 has no data and is used only to write back data, the other two arrays d_D1 and d_ST1 have data.</p> <p>The size of the first array is:</p> <p>d_A1[13000000]</p> <p>The size of the second array is:</p> <p>d_D1[421]</p> <p>The size of the third array is:</p> <p>d_ST1[21]</p> <p>N is 13000000</p> <p>TestArray<<>>(d_A1,N, d_D1, d_ST1);</p> <p>Now I want only pass the data of d_D1[421] and d_ST1[21] to shared arrays so I created the shared arrays as:</p> <pre><code>__global__ void TestArray(int* A1, unsigned int N, int* D1, unsigned int* ST1) { unsigned int __align__(16) tid = threadIdx.x; unsigned int __align__(16) idx = __umul24(blockDim.x, blockIdx.x) + threadIdx.x; __shared__ unsigned int __align__(16) s_D1[441]; //Shared array for d_D1 __shared__ unsigned int __align__(16) s_ST1[21]; //Shared array for d_ST1 if (idx < N) //13000000 { </code></pre> <p>Q. How do I pass the data of d_D1[441] and d_ST1[21] to s_D1[441] and s_ST1[21]? I tried:</p> <pre><code> while (idx < 441) s_D1[tid] = d_D1[idx] __syncthreads(); while (idx < 21) s_ST1[tid] = d_ST1[idx] __syncthreads(); </code></pre> <p>but the computer freezes and I have to restart it. I also tried one at the time,namely, only the fist while and then only the second while, with no luck.</p> <p>If I use the global memory, namely, d_D1, d_ST1 everything works. So the question is: How do you pass data to a shared variable/array when the size of the array is not N? </p> <pre><code> } //End of kernel processing } </code></pre>

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