void opencl_gather_kernel(void *v, int *m, int *o, void *dg, void *u, int *n, void *gd, int *nb, void *b, void *bo, int *op, void *cmd_queue)
void opencl_scatter_kernel(void *v, int *m, void *dg, void *u, int *n, void *gd, int *nb, void *b, void *bo, void *cmd_queue)