Question

I have created following structure ‘data’ in C

typedef struct data
{
  double *dattr;                           
  int d_id;                                
  int bestCent;                            
}Data;

The ‘dattr’ is an array in above structure which is kept dynamic.
Suppose I have to create 10 objects of above structure. i.e.

dataNode = (Data *)malloc (sizeof(Data) * 10);

and for every object of this structure I have to reallocate the memory in C for array ‘dattr’ using:

for(i=0; i<10; i++)
   dataNode[i].dattr = (double *)malloc(sizeof(double) * 3);

What should do to implement the same in OpenCL? How to allocate the memory for array ‘dattr’ once I allocate the memory for structure objects?

Answer 1

As suggested by Faken if you are concern with dynamic memory allocation and you are eager to change the algorithm a little bit, here is some hint:

The following code dynamically allocates local memory space and passes it as the 8th argument to the OpenCL kernel:

  int N; //Number_of_data_points, which will keep on changing as per your requirement  
   size_t localMemSize = ( N* sizeof(int));      
 ...   
 // Dynamically allocate local memory (allocated per workgroup)
 clSetKernelArg(kernel, 8, localMemSize, NULL);