Re: gEDA-user: Icarus Verilog building from CVS

[Dave McGuire <mcguire@neurotica.com>]

On Aug 9, 2004, at 3:35 AM, 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 :-) ).
>  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 ).
  My specifics are UltraSPARC and MIPS.  Binaries generated with GCC 
(with intelligently-selected optimization flags...I've been a GCC user 
since v1.38 was current) are, in nearly all cases, significantly slower 
than with platform-specific vendor compilers.

  I have no desire to get into a pissing match with you over this.  All 
I can say is that I'm glad *you* have had good results with GCC.  From 
my experience, if you're not running x86 (which I'm not) or VAX or M68K 
(which I rarely do anymore), it sucks.

>  If you have any cases which can be reduced to misoptimizations please 
> post a bug report on gcc.gnu.org
>
>  If not, ( and from my opinion and experience ), I can only conider 
> your statement an ill informed opinion.
  Umm, no, frankly I don't have time to chase optimization issues in 
GCC.  The current release of GCC doesn't even compile out-of-the-box on 
the current release of Solaris (my primary development platform).

  I suppose it's possible that image processing and CFD bring out 
different strengths and weaknesses in compilers...while I can't imagine 
this being the case, this is the only thing I can think of that could 
possibly explain the results you're seeing.

  And if you *have* managed to get a recent release of GCC to build 
under Solaris, perhaps you might share a patch.

>  The big thing I have against the beast is it's compilatioon speed and 
> memory requirements, it's slow and big.
  We're in 100% agreement there.

        -Dave

--
Dave McGuire             "...it's a matter of how tightly
Cape Coral, FL             you pull the zip-tie."       -Nadine Miller