title: OpenCL: Moving data from global to local memory issue
body: <p>I have an issue with the following snippet of code:</p>
  
  <pre><code>    tgid = (pixelLoc[get_global_id(0)].x + 0) + (pixelLoc[get_global_id(0)].y + 0) * imWidth;
      plid = (blockSize + 0) + (blockSize + 0) * (blockSize * 2 + 1);
  
      prevCache[plid] = prevFrame[tgid];
  
      barrier(CLK_GLOBAL_MEM_FENCE);
  
      printf("%i : %i\n", prevCache[plid], prevFrame[tgid]);
  </code></pre>
  
  <p>The code should copy a single pixel value of image data to local memory. pixelLoc contains coordinates for all pixel locations which I want to move to local memory. </p>
  
  <p>The issue I am getting is that the if conditional statement should print the same 2 numbers e.g: 34 : 34. As it should have moved the same value from prevFrame to prevCache, however, it is different values.</p>
  
  <p>Any help would be greatly appreciated!</p>