JIT for CTFE

[Moinak Bhattacharyya via digitalmars-d-ldc]

On Wednesday, 2 August 2017 at 18:11:25 UTC, Moritz Maxeiner 
wrote:
> On Wednesday, 2 August 2017 at 17:42:05 UTC, Moinak 
> Bhattacharyya wrote:
>> Has the JIT (ORCJIT) been looked into to take the place of the 
>> interpreter for CTFE? It seems to me this would drastically 
>> widen the scope of CTFE (ie you could now run arbitrary code 
>> at compile time with an appropriate symbol resolver) and would 
>> simplify the codebase too. Thoughts?
>
> Points against:
> - CTFE is part of the frontend shared between D compilers (-> 
> increased maintenance costs)
> - There is a newCTFE in the works by Stefan Koch[1] (-> 
> duplicated effort)
>
> [1] https://github.com/UplinkCoder/dmd/tree/newCTFE
> [2] https://github.com/UplinkCoder/dmd/tree/newCTFE_LLVMBackend

The newCTFE, while a worthwhile effort, is still an interpreter 
and is rendered redundant by JIT'ing. This way, the interpreter 
doesn't need to be added to every time there is a new language 
feature, and a wider range of behavior is enabled (e.g. calling 
to external linkage functions not written in D), which, IMO, 
would be very useful and would enable build-system-in-language 
type behavior like Jai.