Find file
Fetching contributors…
Cannot retrieve contributors at this time
77 lines (69 sloc) 2.7 KB
/* Copyright (c) 1993-2015, NVIDIA CORPORATION. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of NVIDIA CORPORATION nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdio.h>
__global__ void staticReverse(int *d, int n)
{
__shared__ int s[64];
int t = threadIdx.x;
int tr = n-t-1;
s[t] = d[t];
__syncthreads();
d[t] = s[tr];
}
__global__ void dynamicReverse(int *d, int n)
{
extern __shared__ int s[];
int t = threadIdx.x;
int tr = n-t-1;
s[t] = d[t];
__syncthreads();
d[t] = s[tr];
}
int main(void)
{
const int n = 64;
int a[n], r[n], d[n];
for (int i = 0; i < n; i++) {
a[i] = i;
r[i] = n-i-1;
d[i] = 0;
}
int *d_d;
cudaMalloc(&d_d, n * sizeof(int));
// run version with static shared memory
cudaMemcpy(d_d, a, n*sizeof(int), cudaMemcpyHostToDevice);
staticReverse<<<1,n>>>(d_d, n);
cudaMemcpy(d, d_d, n*sizeof(int), cudaMemcpyDeviceToHost);
for (int i = 0; i < n; i++)
if (d[i] != r[i]) printf("Error: d[%d]!=r[%d] (%d, %d)\n", i, i, d[i], r[i]);
// run dynamic shared memory version
cudaMemcpy(d_d, a, n*sizeof(int), cudaMemcpyHostToDevice);
dynamicReverse<<<1,n,n*sizeof(int)>>>(d_d, n);
cudaMemcpy(d, d_d, n * sizeof(int), cudaMemcpyDeviceToHost);
for (int i = 0; i < n; i++)
if (d[i] != r[i]) printf("Error: d[%d]!=r[%d] (%d, %d)\n", i, i, d[i], r[i]);
}