There are discrepance still between what CodeXL thinks about Loveland and what clInfo reports:
CodeXL: Wavefront size: 64
clInfo under 14.12 Omega drivers: Kernel Preferred work group size multiple: 32
Who to trust?
I asked same question many months ago. Answer was if I recall correctly - 64. But 14.12 Omega is newer... and still 32. So, have to ask again...