[LLVMdev] Upstream PTX backend that uses target independent code generator if possible

[Che-Liang Chiou]

Hi there,

I have a working prototype of PTX backend, and I would like to
upstream it if possible.  This backend is implemented by LLVM's target
independent code generator framework; I think this will make it easier
to maintain.

I have tested this backend to translate a work-efficient parallel scan
kernel ( http://http.developer.nvidia.com/GPUGems3/gpugems3_ch39.html
) into PTX code.  The generated PTX code was then executed on real
hardware, and the result is correct.

So far I have to hack clang to generate bitcode for this backend, but
I will try to patch clang to parse CUDA (or OpenCL) while I am
upstreaming this backend.

I am new to LLVM.  Any comments are welcome.

Regards,
Che-Liang