plugin-provided pragmas & Fortran or Ada?

plugin-provided pragmas & Fortran or Ada?

[Basile Starynkevitch]

Hello,

Assuming a plugin (e.g. MELT) add a new pragma using PLUGIN_PRAGMAS, is
this pragma usable from Ada or Fortran code?

I am not very familiar with Ada or Fortran. I believe Ada has some
syntax for pragmas -but do Ada pragma have the same API inside GCC
plugins as C or C++ pragmas?- and I am not sure about Fortran. Many
Fortran dialects or implementations parse specially some kind of
comments -but I don't know if these are giving pragma events to plugins.

The intended MELT extension I have in mind would convert Gimple (built
by GCC from Ada or C or C++ or Fortran code) to some low-level C code
suitable for Frama-C. Frama-C is a free (LGPL licensed, coded in Ocaml)
static analyzer developed by my colleagues at CEA LIST (& also INRIA
Proval team). See http://frama-c.com/

Frama-C accept some special comments starting with /*@ in a language
called ACSL, see http://frama-c.com/acsl_tutorial_index.html and I was
thinking of using some new pragmas inside GCC to translate these pragmas
to ACSL syntax comments.

All this is exploratory work initiated by my intern Jeremie Salvucci. We
have no idea today if this can be worked out.

Cheers.
-- 
Basile STARYNKEVITCH         http://starynkevitch.net/Basile/
email: basile<at>starynkevitch<dot>net mobile: +33 6 8501 2359
8, rue de la Faiencerie, 92340 Bourg La Reine, France
*** opinions {are only mines, sont seulement les miennes} ***

Re: plugin-provided pragmas & Fortran or Ada?

[Duncan Sands]

Hi Basile,

> Assuming a plugin (e.g. MELT) add a new pragma using PLUGIN_PRAGMAS, is
> this pragma usable from Ada or Fortran code?
>
> I am not very familiar with Ada or Fortran. I believe Ada has some
> syntax for pragmas -but do Ada pragma have the same API inside GCC
> plugins as C or C++ pragmas?- and I am not sure about Fortran. Many
> Fortran dialects or implementations parse specially some kind of
> comments -but I don't know if these are giving pragma events to plugins.

I'm pretty sure this won't work for Ada without modifying the Ada
front-end.

Ciao,

Duncan.

Re: plugin-provided pragmas & Fortran or Ada?

[Basile Starynkevitch]

On Tue, 2010-06-22 at 08:58 +0200, Duncan Sands wrote:
> Hi Basile,
> 
> > Assuming a plugin (e.g. MELT) add a new pragma using PLUGIN_PRAGMAS, is
> > this pragma usable from Ada or Fortran code?
> >
> > I am not very familiar with Ada or Fortran. I believe Ada has some
> > syntax for pragmas -but do Ada pragma have the same API inside GCC
> > plugins as C or C++ pragmas?- and I am not sure about Fortran. Many
> > Fortran dialects or implementations parse specially some kind of
> > comments -but I don't know if these are giving pragma events to plugins.
> 
> I'm pretty sure this won't work for Ada without modifying the Ada
> front-end.

Are there any plugin hooks for Ada pragmas? Perhaps the Ada team might
consider adding some, if it is simple enough. Specific pragmas have
definitely their places in plugins.

Cheers.

-- 
Basile STARYNKEVITCH         http://starynkevitch.net/Basile/
email: basile<at>starynkevitch<dot>net mobile: +33 6 8501 2359
8, rue de la Faiencerie, 92340 Bourg La Reine, France
*** opinions {are only mines, sont seulement les miennes} ***

Re: plugin-provided pragmas & Fortran or Ada?

[Tobias Burnus]

On 06/22/2010 06:20 AM, Basile Starynkevitch wrote:
> Assuming a plugin (e.g. MELT) add a new pragma using PLUGIN_PRAGMAS, is
> this pragma usable from Ada or Fortran code?
> 
> I am not very familiar with Ada or Fortran. I believe Ada has some
> syntax for pragmas -but do Ada pragma have the same API inside GCC
> plugins as C or C++ pragmas?- and I am not sure about Fortran. Many
> Fortran dialects or implementations parse specially some kind of
> comments -but I don't know if these are giving pragma events to plugins.

Regarding Fortran: "Pragmas" seem to be only rarely used in Fortran
programs - with possible exception of the !DEC$ directives, which seem
to be mostly used for attributes and has been superseded mostly by the C
bindings of Fortran; !DEC$ has also been used for parallelization as
precursor of OpenMP.

gfortran only supports setting some attributes via !GCC$ (and supports
OpenMP) - but nothing more; cf.
http://gcc.gnu.org/onlinedocs/gfortran/GNU-Fortran-Compiler-Directives.html
The plan is to support all function/variable attributes, but that's
still on the TODO list. Additionally, one might add more functionality,
but that's currently not even on the TODO list.

Thus, if you need more, it has to be programmed.

Tobias

Re: plugin-provided pragmas & Fortran or Ada?

[Duncan Sands]

Hi Basile,

>>> Assuming a plugin (e.g. MELT) add a new pragma using PLUGIN_PRAGMAS, is
>>> this pragma usable from Ada or Fortran code?
>>>
>>> I am not very familiar with Ada or Fortran. I believe Ada has some
>>> syntax for pragmas -but do Ada pragma have the same API inside GCC
>>> plugins as C or C++ pragmas?- and I am not sure about Fortran. Many
>>> Fortran dialects or implementations parse specially some kind of
>>> comments -but I don't know if these are giving pragma events to plugins.
>>
>> I'm pretty sure this won't work for Ada without modifying the Ada
>> front-end.
>
> Are there any plugin hooks for Ada pragmas? Perhaps the Ada team might
> consider adding some, if it is simple enough. Specific pragmas have
> definitely their places in plugins.

I'm pretty sure there are no such plugin hooks right now.

Ciao,

Duncan.

Re: plugin-provided pragmas & Fortran or Ada?

[Eric Botcazou]

> Are there any plugin hooks for Ada pragmas? Perhaps the Ada team might
> consider adding some, if it is simple enough. Specific pragmas have
> definitely their places in plugins.

The Ada front-end is entirely isolated from the middle-end so we would need to 
devise a way of allowing the latter to dynamically affect the former.  That's 
certainly doable but not immediate.

-- 
Eric Botcazou