llvm dev - Jun 2020 - [cfe-dev] [flang-dev] [RFC] Refactor Clang: move frontend/driver/diagnostics code to LLVM

On 6/11/20 3:32 AM, Andrzej Warzynski wrote:
>
>
> On 11/06/2020 00:49, Michael Kruse wrote:
>> Am Mi., 10. Juni 2020 um 10:04 Uhr schrieb Doerfert, Johannes via
>> flang-dev <flang-dev at lists.llvm.org>:
>>> I'm not against a subproject *but* if we also move the existing
>>> llvm/lib/Frontend stuff, that would introduce a dependence from
>>> llvm-core to this project, which I think is uncommon. We could also
>>> have
>>> both. At the end of the day it depends on the benefit we would get
from
>>> an independent subproject.
>>
>> If we have non-conditional dependencies llvm-core->frontend-support
>> and frontend-support->llvm-core, what advantage is there left of
>> making frontend-support a subproject? Both of them are required all
>> the time.
>>
>> Michael
>>
>
> Thanks for the feedback! It sounds like we should keep 
> llvm/lib/Frontend in LLVM and `frontend-support` would be a new 
> subproject for things unrelated to LLVM IR.
Sure, if we expect usage of such a subproject without llvm-core. (Maybe 
there are other reasons to separate it but I'm not sure I understood them.)


Thanks,

   Johannes

>
> -Andrzej

I think the expectation is that LLVM remains at the bottom of the
dependency tree, with frontend-support depending on LLVM, and Clang and
Flang depending on frontend-support (and LLVM).

Not everything which makes sense to share between clang and flang makes
sense to be part of llvm core. E.g., implementation of a GCC-compatible
command-line compiler-driver seems like it would be very much out-of-place
in llvm core.


On Thu, Jun 11, 2020 at 10:28 AM Doerfert, Johannes via cfe-dev <
cfe-dev at lists.llvm.org> wrote:
> On 6/11/20 3:32 AM, Andrzej Warzynski wrote:
> >
> >
> > On 11/06/2020 00:49, Michael Kruse wrote:
> >> Am Mi., 10. Juni 2020 um 10:04 Uhr schrieb Doerfert, Johannes via
> >> flang-dev <flang-dev at lists.llvm.org>:
> >>> I'm not against a subproject *but* if we also move the
existing
> >>> llvm/lib/Frontend stuff, that would introduce a dependence
from
> >>> llvm-core to this project, which I think is uncommon. We could
also
> >>> have
> >>> both. At the end of the day it depends on the benefit we would
get from
> >>> an independent subproject.
> >>
> >> If we have non-conditional dependencies
llvm-core->frontend-support
> >> and frontend-support->llvm-core, what advantage is there left
of
> >> making frontend-support a subproject? Both of them are required
all
> >> the time.
> >>
> >> Michael
> >>
> >
> > Thanks for the feedback! It sounds like we should keep
> > llvm/lib/Frontend in LLVM and `frontend-support` would be a new
> > subproject for things unrelated to LLVM IR.
>
> Sure, if we expect usage of such a subproject without llvm-core. (Maybe
> there are other reasons to separate it but I'm not sure I understood
them.)
>
>
> Thanks,
>
>    Johannes
>
>
> >
> > -Andrzej
>
>
> _______________________________________________
> cfe-dev mailing list
> cfe-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20200611/1e16b37a/attachment.html>

On 6/11/20 4:04 PM, James Y Knight wrote:
> I think the expectation is that LLVM remains at the bottom of the
> dependency tree, with frontend-support depending on LLVM, and Clang and
> Flang depending on frontend-support (and LLVM).
>
> Not everything which makes sense to share between clang and flang makes
> sense to be part of llvm core. E.g., implementation of a GCC-compatible
> command-line compiler-driver seems like it would be very much out-of-place
> in llvm core.
That clears things up, thanks a lot. So we could have a frontend-support

subproject for non-LLVM(-IR) related things and `llvm/lib/Frontend` for

LLVM(-IR) related stuff, e.g., IR generation parts.


Thanks,

   Johannes

> On Thu, Jun 11, 2020 at 10:28 AM Doerfert, Johannes via cfe-dev <
> cfe-dev at lists.llvm.org> wrote:
>
>> On 6/11/20 3:32 AM, Andrzej Warzynski wrote:
>>>
>>> On 11/06/2020 00:49, Michael Kruse wrote:
>>>> Am Mi., 10. Juni 2020 um 10:04 Uhr schrieb Doerfert, Johannes
via
>>>> flang-dev <flang-dev at lists.llvm.org>:
>>>>> I'm not against a subproject *but* if we also move the
existing
>>>>> llvm/lib/Frontend stuff, that would introduce a dependence
from
>>>>> llvm-core to this project, which I think is uncommon. We
could also
>>>>> have
>>>>> both. At the end of the day it depends on the benefit we
would get from
>>>>> an independent subproject.
>>>> If we have non-conditional dependencies
llvm-core->frontend-support
>>>> and frontend-support->llvm-core, what advantage is there
left of
>>>> making frontend-support a subproject? Both of them are required
all
>>>> the time.
>>>>
>>>> Michael
>>>>
>>> Thanks for the feedback! It sounds like we should keep
>>> llvm/lib/Frontend in LLVM and `frontend-support` would be a new
>>> subproject for things unrelated to LLVM IR.
>> Sure, if we expect usage of such a subproject without llvm-core. (Maybe
>> there are other reasons to separate it but I'm not sure I
understood them.)
>>
>>
>> Thanks,
>>
>>     Johannes
>>
>>
>>> -Andrzej
>>
>> _______________________________________________
>> cfe-dev mailing list
>> cfe-dev at lists.llvm.org
>> https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
>>