appendix D: OpenCL on mobile devices Each new generation of mobile devices provides more capabilities than the last, and it's only a matter of time before high-performance embedded computing becomes a serious priority. A great deal of this performance will be provided by the devices' GPU s, so it's important to understand how Open CL operates on handheld and mobile devices. Chapter 10 of the Open CL 1.1 standard defines the Open CL Embedded Profile. This is the criteria that embedded devices must meet to be considered Open CL - compliant. These requirements are a subset of the rules that apply to desktop sys- tems, so there's nothing significantly new or different to learn. But when you're porting Open CL code to run on a tablet computer or smart phone, it's crucial to know which capabilities are available and which aren't. First, Open CL provides a macro that kernels can check to see if the target imple- ments the embedded profile: __EMBEDDED_PROFILE__ . If this macro is set to 1, the kernel can only access an abridged set of Open CL capabilities. Otherwise, the ker-