How to obtain the valuse of get_local_id(0), get_group(0) and get_local_range(0) in single_task

Hi support team / Daouda

Following your suggestion to modify the single_task function for the kernel, I can get the result I expect now. However, if I set the for loop condition too large (size_t id = 0; id < global(I will use 65536, or 65536/4, 65536/8...); id++), FPGA hardware(arria10) will run very long time and even fail in some large condition case. Do you have any suggestion about how to optimize it? Currently, I only add unroll(with factor 1) on the loop. May you suggest me other optimization methods can use in my case? I need to decrease the kernel execution time when using FPGA hardwares.

below is my modified code(i use id<4 now)

h.single_task<class bude_kernel>([=]() [[intel::kernel_args_restrict]] {

#pragma unroll 1
for (size_t id = 0; id < 4; id++) {

const size_t lid = id;
const size_t gid = id;
const size_t lrange = 1;

float etot[NUM_TD_PER_THREAD];
cl::sycl::float3 lpos[NUM_TD_PER_THREAD];
cl::sycl::float4 transform[NUM_TD_PER_THREAD][3];

size_t ix = gid * lrange * NUM_TD_PER_THREAD + lid;
ix = ix < nposes ? ix : nposes - NUM_TD_PER_THREAD;

#pragma unroll 1
for (int i = lid; i < ntypes; i += lrange) local_forcefield[i] = forcefield[i];
#pragma unroll 1
for (size_t i = 0; i < NUM_TD_PER_THREAD; i++) {
size_t index = ix + i * lrange;

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