[LLVMdev] Potential Google Summer of Code Applicant

[Yiannis Tsiouris]

On 4/6/12 2:21 AM, Talin wrote:
> I would really like to see someone work on LLVM's garbage collection 
> support - it hasn't been updated in 4 years, and while there's been a 
> lot of talk about ways that it could be improved, there's been no action.
That is *sooo* true! :-) I'm one of the authors of an LLVM backend for 
Erlang (ErLLVM [1]); we have tested and measured our backend  and 
noticed that with the current GC infrastructure we see 20-40% 
performance degradation (because of the loads/stores on the stack for 
all gcroots). It is clear to me and the rest of the team that with this 
infrastructure the LLVM might not be suitable for languages with 
explicit garbage collection, like Erlang. I've also studied the way the 
Vmkit project handles GC and they seem to face the same deficiency too.

offtopic: I am working on an email (more like an RFC) with all the 
details and patches to the LLVM project in order to support our Erlang 
backend. I hope I will be able to send it by next week. Note, that we 
have already talked with the Ericsson/OTP team about integrating our 
work in a future release of Erlang/OTP (as a new HiPE backend).

Yiannis

[1]: http://erllvm.softlab.ntua.gr

-- 
Yiannis Tsiouris
Ph.D. student,
Software Engineering Laboratory,
National Technical University of Athens
WWW: http://www.softlab.ntua.gr/~gtsiour