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VGPR usage question (code attached)

Question asked by yurtesen on Feb 15, 2013
Latest reply on May 6, 2015 by jason

I have a simple test kernel which I compile in kernelanalyzer2. It says on Tahiti it will use 110 VGPR. I tried to put #pragma unroll 1 and it does not have any effect at all. Is there a known way to avoid compiler from using so many registers? ( keep in mind this is a dummy test kernel, but this seems to effect an actual kernel and reduce occupancy)

 

__kernel void test (__global double *distrValues, __global double *distrValuesOut) {
    __private const int id = get_global_id(0);
    __private double den2;
      
  __private int i;

   for (i=0;i<53;i++) {
       den2 += distrValues[i];
   }
    distrValuesOut[id]=den2;
}

 

 

Thanks!

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