[LLVMdev] Upstreaming PNaCl's IR simplification passes

[Chris Lattner]

On Mar 6, 2014, at 10:23 AM, David Sehr <sehr at google.com> wrote:
> Now to the steps ahead:  I propose Mark sends some patches for the simpler passes out to let you, our esteemed colleagues, discuss them concretely.  As several have noted, these patches could be interesting to them, and it seems reasonable to pass them along here for the potential benefit of those folks. Also as Alon noted, it would be nice to have this underway before he comes back with his backend work.  Your thoughts are respectfully solicited.

I agree, I don't think that an abstract discussion is useful here, lets talk details.

One point though: I don't understand the claims that this will make it easier to write a backend.  The LLVM backend infrastructure already handles the lowering of constantexprs and others constructs for a target.  AFAIK, these sorts of lowering passes would only help someone not using our target.

Supporting pnacl and emscripten are still worthwhile goals if the maintenance complexity is balanced right, I just have never understood the point about simplifying target descriptions.

-Chris