Questions about ioc64 and Intel compiler icc in regard of OpenCL

Hi,

It is known that, to get a GPU device associated with a platform, CL_DEVICE_TYPE_GPU is used in clGetDeviceIDs; So my first question is:
Is it necessary when using ioc64, to specify as device gpu? And if yes, what is the difference in term of code generated between -device=cpu and -device=gpu?

My second question is: Is there any particular reason why the Intel c compiler does not support OpenCL?

Thanks