Yes, and it requires quite a low-level understanding of the architecture to "think GPU". SIMD, warps, blocks, threads, different memory types, no branching/iden

Yes, and it requires quite a low-level understanding of the architecture to "think GPU". SIMD, warps, blocks, threads, different memory types, no branching/identical branching per core, ... Some of this could probably be abstracted away but you definitely need to be aware and adjust algorithms appropriately. You can't just convert code and hope for the best, unless you just want a slow co-processor.