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Re: [f-cpu] Winograd DCT on my seul.org account

On Sat, Apr 20, 2002 at 04:55:07AM +0200, cedric wrote:
> > I guess that writing a new C compiler will indeed be easier than
> > hacking gcc.
> Euh, well,... I didn't agry with you, writing a C compiler is very hard (It 
> actually didn't exist any bison grammar for C). And a lot of thing in the 
> C/C++ norme are not clear specified (It's explain the problem with the 3.0.x 
> version of gcc). So when you want to write your own C compiler, you must test 
> it with a lot of different software and... have a lot of problem.

I have yacc/bison grammars for both C89 and C99 (the grammar for several
versions of GNU C is also available, of course).

The problem with gcc 3 is that some former GNU extensions are now also
defined in C99 -- but with slightly different semantics (e.g. `inline').

> And I recently read the gcc documentation about how to write a backend to gcc 
> and it's not easy, but we can have some possibility and we could have some 
> good performance. The only problem is with SIMD and perhaps some optimisation 
> with our cray like load/store.
> 	I thing that nicolas that says to me that for the 3.1 release they will have 
> some SIMD optimisation. With our clean ASM, it will certainly be possible to 
> use it.
> 	Last point, if we write one backend, we can have all the gcc frontend 
> working on our CPU, and that much more interesting.
> 	That's only my point of view, and for me coding a C/C++ compiler will 
> be a nightmare... 

When I see a fully functional F-CPU gcc backend that creates reasonably
efficient code, I will believe that it's possible. Writing such a
beast is what I call a nightmare (I don't like hacking other people's
ugly code).

 Michael "Tired" Riepe <Michael.Riepe@stud.uni-hannover.de>
 "All I wanna do is have a little fun before I die"
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