[LLVMdev] PROPOSAL: Rename Target R600 -> AMDGPU

[Tom Stellard]

Hi,

Now that the 3.5 branch has been made, I would like to propose renaming
the R600 target to AMDGPU.

R600 is the name of an AMDGPU GPU that was released about 8 years ago.
The R600 backend supports this GPU and also all other GPUs which have
been made since then.  When people see the name R600 they often assume that
only the older GPU family is supported which is not true.

The reason that the backend was originally called R600 and not AMDGPU
is because there was concern that the name AMDGPU was too generic, and it
would be confusing if AMD came out with a new architecture which required a
new backend.  In this happened, we would have an AMDGPU backend, which didn't
support all AMD GPUs.

We actually have an example of this situation today with ARM and ARM64, and
this doesn't seem to have caused too much confusion.  Plus, I would much
prefer people try a backend thinking something was supported and have
it not work than people assuming the backend didn't work for their GPU
and ignoring it completely.

If I were to rename the backend, I would keep the name R600 around in the
autoconf and CMake build systems for at least one release for compatibility, and 
I would also add a new triple: amdgpu.

What does everyone think about this?  Are there any potential pitfalls with renaming
that I should be aware of?

Thanks,
Tom