MotörSYCL

MotörSYCL (MotorSYCL) is a prototype Khronos SYCL implementation; a header-only library for the nvc++ compiler (from NVIDIA's HPC SDK).

The following program code is derived from the small test suite included in the tests subdirectory. The program demonstrates use of Unified Shared Memory (USM) via device allocations. Similar functionality for USM shared allocations and system allocations can be seem in tests/usm_shortcuts.cpp.

#include <sycl/sycl.hpp>
#include <cassert>
#include <numeric>

// USM Device Allocations

// nvc++ -stdpar -std=c++20 -I include example.cpp

int main(int argc, char *argv[])
{
  using namespace sycl;
  const unsigned sz{1024};
  range<1> r{sz};
  queue q;

  bool b = q.get_device().has(aspect::usm_device_allocations);
  assert(b);

  unsigned *d_p = malloc_device<unsigned>(sz,q); // USM pointer
  unsigned h[sz];
  std::iota(std::begin(h), std::end(h), 0);

  q.memcpy(d_p, h, sz * sizeof(unsigned));
  q.parallel_for(r, [=](id<1> i) { d_p[i] += i; });
  q.wait();
  q.memcpy(h, d_p, sz * sizeof(unsigned));

  for (unsigned i = 0; i < sz; ++i)
    b = b && (h[i] == 2*i);

  assert(b);

  free(d_p, q); // sycl::free

  return 0;
}

The code above comes from the example.cpp file; found in the same directory as this readme. The command required to build it is:

nvc++ -stdpar -std=c++20 -Wno-deprecated-declarations -I include example.cpp