title: Are there any warp voting functions in OpenCL?
body: <p>In CUDA there are <code>__ballot()</code>, <code>__any()</code>, <code>__all()</code>, <code>__popc()</code> and a bunch of lanemask functions to perform warp voting operations across all lanes (usually with the size of 32) within a warp. I'm wondering is there any such functions implemented in OpenCL to perform the same operations within one wavefront. If there is no such function, I may need to implement them as inline functions myself to use in my project.</p>