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Re: gEDA-user: Icarus Verilog building from CVS

On Mon, Aug 09, 2004 at 09:35:29AM +0200, Lars Segerlund wrote:
>  Well, I am running some computationally intensive code, ( CFD ), and
>  gcc 3.5 ( upcoming ) is giving a boost of up to 30 % for FORTRAN and
>  C code in some instances. 
>  The 'new' gcc does have a much better optimization framework, and it
>  is really starting to show, it should fx. be able to run head to head
>  with intels compiler provided that it is supplied with a reasonable
>  set of compiler flags, ( which is an area of itself :-) ). 

This is good to hear.  It doesn't yet help those of us who need a stable
compiler though, does it?

>  SO if you look for the code generated by the 'state of the art' gcc i
>  do not believe your statement to be true, ( check out code for the sh
>  and h8 processors or the mips32 instruction set ). 

It seems to me that it is reasonable to make qualitative statements
about a product based on it's stable releases, not it's beta or alpha
code.  Until GCC 3.5 is ready, it is far to say that GCC stinks at
optimizing for certain platforms.
>  If you have any cases which can be reduced to misoptimizations please
>  post a bug report on gcc.gnu.org 

If our GCC bug is still present in 3.4, I will be reporting it.  We
currently use 3.2.1 for SH3, but are in the process of migrating.
>  If not, ( and from my opinion and experience ), I can only conider
>  your statement an ill informed opinion. 

Wait, you telling us we are ill informed because we make a statement
about how things were quite recently?  My impression is that GCC 3.4
still isn't fully stable in some environments, AND it still isn't as
fast as Sun and MIPS vendor compilers.

Here at work I'm trying to get us moved up to 3.4 for the SH3 platform.
You now have me very curious about trying 3.5 on this platform.  We've
been using 3.2.1 for our SH3 work, and it has a bug in it that forces us
to use -O1 optimization.
>  ( btw. dec's compiler used to build on gcc :-) especially the openMP
>  part ), and this should give some indication of the performance of
>  gcc. 

The OpenMP part was build on gcc?  But, gcc doesn't support openmp
(unless 3.5 is adding it), to my understanding.  And this is an area
that I'm doing my best to stay abreast of developments in.