Hello, On Tue, May 21, 2013 at 3:46 PM, Andy Wingo <wi...@pobox.com> wrote:
> You should have two names: the original ones and the gensyms that come > from tree-il. Creating new gensyms should happen when copying or > fabricating new nodes, as peval does, but in most cases you don't need > to do it, and in any case it can be tricky. > > I would take tree-il as the guide here. > I'll look at it, thanks. > I haven't handled source information yet, but to the CPS->RTL compiler > it will look like emitting special instructions, like the tree-il->glil > compiler emits <glil-source> nodes. > That sounds fairly simple to implement. > This is lambda-properties. You just pass them through, and add them to > the begin-program in the RTL. > Again, this seems relatively simple to do. > Note that wip-rtl-may-2013 and the RTL branches that are under review > for master are slightly different from the ones you have. Their > begin-program has a second argument, the procedure properties, and the > first argument is a label and not a name. They have begin-*-arity and > end-arity for marking arity information and performing arity prologues. > There are some slight changes to instructions but not much. OTOH they > do have some better type checking and a disassembler that works, so many > things should be easier ;) Compare the rtl.test there and your rtl.test > for details. > > > * Why is there no "let" that can bind functions? You don't always > > want > > to set up a recursive binding environment. > I think right now the Tree-IL->CPS compiler will turn (let ((f (lambda ...))) ...) into something like this: ((lambda (f-12345) .... let body here ....) (letrec ((f-func (lambda ... f's body here ...))) f-func)) (I'm not showing the continuation's name because it would make it even more complicated than it already is.) I agree that this is a crazy way to do it. It should detect this case and skip the extra steps. > Understood. However the question of language is fundamental for > enabling collaboration on this code. I would be very happy to see a CPS > language definition that could express all of Tree-IL. I don't think > this would take a lot of work -- it is perfectly acceptable to throw > "unimplemented" for those parts of the compiler that aren't there yet, > but the language itself should be adequately expressive. IMHO anyway. > > Do you think you will have time to do that over the next few days or so? > Apologies for the pressure, just that I would like to do some things in > this area and am not sure how best to do them :) > This is interesting - I had been adding to the language as I needed features, and not really thinking of it as an interface. But you might be right. I just started rebasing tonight, and I hope to work more on it in the next two days. But I don't want to be a blocker for your work - what are you trying to do? Thanks a lot, Noah
