I think you're looking for this: http://gpuopen.com/amdgcn-assembly/
Also there are more unofficial ways to produce ELF kernels from GCN asm. For example the CLRadeonExtender, or my thing: hetpas. The latter has a small IDE with GCN code completion and the first one has the most complete GCN instruction support I know. The problem with these that we have to follow the new drivers but nowadays I personally don't, so at least with my stuff you have to use old drivers. I've had no time yet to try out the official ROC solution, but I believe that this will be up to date with the newest drivers.
Thanks for you Answer.
I was missing some basic knowledge.
You can use HSA to load a hsaco file.
Those hsaco Files can be created in many ways.
Its possible to use OpenCL, HCC, HSAIL or GCN Assembly to write kernels
which you then can turn into hsaco files.
Then you can use 'hsa_executable_load_code_object' to load the hsaco file.