Re: [Tinycc-devel] C6x Port

[Fabrice Bellard]

Thank you! Note that a small change in release 0.9.17 or 0.9.18 will be 
that function calls will be generated differently. The idea is to leave 
the function arguments in the 'vstack' and to let the processor specific 
stuff do all the argument packing and function calls. On i386 it will be 
slightly less efficient (because if more than three arguments are used a 
temporary variable will be created on the stack before being pushed) but 
it will ease the porting of TCC on all other architectures and allow 
correct implementation of alloca(), gcc builtin functions and inlining.

Fabrice.

[Note: I will be on holidays during the next week - so don't be 
surprised if you get no answer from me].

Tom Kerekes wrote:
> Fabrice,
>
> You should be able to get the current source at:
>
> http://dynomotion.com/compiler.html
>
> I think the COFF formats for TI and Windows are very different so don't
> expect it to be useful for generating windows code.
>
> I tried to put #if (DO_C67) switches everywhere to identify the changes.
>
> The generated code is probably 3X slower and larger than code generated
> by TI's compiler, because of a lot of unnecessary loads/stores, nops,
> and no real utilization of the parallel nature of the processor.  But
> for me, I find that for 99% of a DSP application I don't care about
> speed and the 1% of the code that is critical is usually hand optimized.
> Anyway, I took the simplest route to get it working at the expense of
> speed/efficiency.
>
> The TI compiler also expects the first 10 parameters of a function to be
> passed in registers.  I tried to maintain values in registers, but kept
> running into problems (nested function calls), so I finally gave up and
> just pushed them on the stack and popped them just before the call.
>
> Thanks again
>
> TK
>
>  
>
>
> -----Original Message-----
> From: Fabrice Bellard [mailto:address@hidden 
> Sent: Friday, March 07, 2003 2:58 AM
> To: TK; address@hidden
> Subject: Re: [Tinycc-devel] C6x Port
>
> Hi,
>
> I am very interested to see your source code (TCC has never been ported 
> before - and generating COFF instead of ELF is also very interesting - 
> even for x86 it would be useful for a windows port). Can you send it to 
> me or to the mailing list or give a link ? Since TCC is released under 
> the GPL you can do anything with it (including selling it) provided you 
> release the source code.
>
> Fabrice.
>
> TK wrote:
>
> > Fabrice,
> >
> > Thanks for writing an incredibly concise C compiler, the code is truly
> > beautiful.
> >
> > I have attempted a TCC port to the TI C6711 DSP.  To my knowledge it
>
> is
>
> > the only available "free" compiler for the C6x.  (TI has an excellent
> > compiler called Code Composer, but it sells for $3-4K, and is somewhat
> > slow).
> >
> > It generates a COFF output file that is fairly compatible with Code
> > Composer's.  Including function calls, debug line numbers, and global
> > symbols.
> >
> > Currently it compiles under MS VC++ 6.0 and runs under MS Windows, but
> > it wouldn't be hard to change back to Linux.  If anyone has any
>
> interest
>
> > I can post the code somewhere.
> >
> > I am hoping to distribute this with a C6x DSP board I am designing.
> > Would this be OK?  Are their any legal issues?
> >
> > Thanks again
> >
> > TK


--
Fabrice.