On 2024-02-27 11:15, Richard Biener via Gcc wrote: > On Fri, Feb 23, 2024 at 10:22 AM Miro Palmu via Gcc <gcc@gcc.gnu.org> wrote: >> >> Hi. >> >> I have a idea about long term hobby project relating to gcc, >> so with this email I'm asking feedback about the idea >> early rather than later. First little bit of context. >> >> I'm a student deep in a university course about compilers >> and I have been writing a compiler for language >> which is a subset of Herb Sutter's Cpp2. >> I chose this because I'm bit of a Cpp language nerd, >> and I can apply all of my Cpp knowledge to this project, which is fun. >> >> After the course I'm interested in converting this to a front end to gcc, >> with goal of learning about front end development to gcc. >> (It is a non-goal to try to upstream the project.) >> >> I don't see any obvious reason why this would not be possible. >> It just need to be able to target (C++ version of ?) GENERIC. >> This would be the first goal of the compiler >> and would serve as the MVP of the project. >> Below is discussing/theorizing post MVP goals. > > Note there is no textual form of GENERIC that a GCC compiler > binary could parse. So your Cpp compiler would need to build > GENERIC data structures itself, basically be a real GCC language frontend.
Yes, that is my plan. This is little late reply, so I had already started the conversion last week and at the moment I have the boilerplate implemented for the front end. > The alternative is to use GCCs JIT but that emits GIMPLE only > (I think there's a rust frontend project that tries to leverage that, > and also GNU emacs is using it). That is interesting. Have to read more about it, thanks for mentioning! >> Because the Herb Sutter's cppfront transpiles Cpp2 to Cpp1, >> it is easy to have mix of Cpp1 and Cpp2 global level constructs >> in the same file. Just generate forward declarations of everything, >> keep Cpp1 definitions unchanged and transpile the Cpp2 ones. >> >> At the moment my subset Cpp2 does not support this compatibility >> but it would be nice to have at some point. >> But if my front end targets GENERIC I would have to use g++ machinery >> to turn the Cpp1 parts to GENERIC and then somehow combine the trees. >> I imagine that somebody with more experienced with GENERICs would have >> a intuition on how hard this combinations would be to implement. >> I'm curious about this intuition which I lack. >> >> In Cpp2 one can import and export Cpp1 modules. With transpiling to >> Cpp1 this again is easy implement but with potential front end, >> I'm not sure. I'm quite ignorant on Compiled Module Interface (CMI) >> implementation in gcc, so I'm asking just for guidance on where to look >> if one would want to learn on how CMIs are implemented. > > There's no generic code for implementing CMIs, each frontend requiring such > does need to implement that on its own. > > Hope this helps, > Richard. > Yes. Thanks again! >> Thanks! >> >> -- >> Miro Palmu -- Miro Palmu
