Is it possible to run piece of pure C++ code in GPU

Question

I don't know OpenCL very much but I know C/C++ API requires programmer to provide OpenCL code as a string. But lately I discovered ArrayFire library that doesn't require string-code to invoke some calculations. I wondered how is it working (it is open source but the code is a bit confusing). Would it be possible to write parallel for with OpenCL backend that invokes any piece of compiled (x86 for example) code like following:

template <typename F>
void parallel_for(int starts, int ends, F task) //API
{ /*some OpenCL magic */ }
//...
parallel_for(0, 255, [&tab](int i){ tab[i] *= 0.7; } ); //using

PS: I know I am for 99% too optimistic

Answer 1

You cannot really call C++ Host code from the device using standard OpenCL. You can use SYCL, the Khronos standard for single-source C++ programming. SYCL allows to compile C++ directly into device code without requiring the OpenCL strings. You can call any C++ function from inside a SYCL kernel (as long as the source code is available). SYCL.tech has more links and updated information.