[Radiance-general] Compile error on AMD running Fedora 4

[Jack de Valpine]

Hi,

It might also be worth checking Mark Stock's benchmark page:

http://mark.technolope.org/pages/rad_bench.html

for some other compile options.

-Jack

atelier iebele abel wrote:

> Hi Ian,
>
> I used your recommended gcc options an got an rendering speed 
> improvement of 1.035. That is 3.5 % (!).
> I used gcc 4.0(etc, I dont know exactly) but did not find any option 
> like "auto vectorization". We'll have to wait for that coming up in 
> the future i think.
> Thanks a lot for figuring out these settings so far !
>
> Iebele
>
>
>
>
> Ian Tester wrote:
>
>> iebele wrote:
>>
>>> Current rmake command is:
>>> #!/bin/sh
>>> exec make "SPECIAL=" \
>>>         "OPT=-m64 -O3 -mfpmath=sse -DSPEED=200" \
>>>         "MACH=-Dlinux -D_FILE_OFFSET_BITS=64 -L/usr/X11R6/lib
>>> -I/usr/include/X11 -DNOSTEREO" \
>>>         ARCH=IBMPC "COMPAT=bmalloc.o erf.o getpagesize.o" \
>>>         INSTDIR=/usr/local/bin \
>>>         LIBDIR=/usr/local/lib/ray \
>>>         ESUFFIX= \
>>>         CC=gcc "$@" -f Rmakefile
>>
>>
>>
>>
>> What version of gcc is installed on your system?
>> Check using gcc -v
>>
>> Looking at the man page for gcc-3.4 on my Debian (Athlon XP) system, 
>> I'd suggest the following settings:
>>
>> -march=k8    to enable the AMD64 instructions, implies the same
>>         argument to -mtune.
>>
>> -msse2        to enable SSE2 instructions. Without this, the 
>> -mfpmath=sse
>>         option is useless.
>>
>> -mfpmath=sse,387 this will give you a boost if the SSE unit is separate
>>         from the old x87 unit but I don't know enough about the K8
>>         architecture to know if it does. It will try to use both
>>         execution units, but the man page says it still
>>         experimental.
>>
>> -ffast-math    the man page says this is dangerous but I've never 
>> noticed          any problems myself. Try it if you want.
>>
>> Apart from that, wait for upcoming GCC-4.x releases to flesh out its 
>> optimisation features, in particular auto vectorization. The SSE2 
>> instruction set can handle double precision FP math, better than the 
>> single precision in SSE or Altivec. You should theoretically be able 
>> to get some pretty awesome performance out of that processor. Reality 
>> is another matter though... :(
>>
>> My other suggestion would be to check out some Gentoo web sites. 
>> Those guys are nuts about compiler optimisations :P
>>
>> bye
>>
>> _______________________________________________
>> Radiance-general mailing list
>> Radiance-general at radiance-online.org
>> http://www.radiance-online.org/mailman/listinfo/radiance-general
>>
>
> _______________________________________________
> Radiance-general mailing list
> Radiance-general at radiance-online.org
> http://www.radiance-online.org/mailman/listinfo/radiance-general
>
>

-- 
#	John E. de Valpine
#	president
#
#	visarc incorporated
#	http://www.visarc.com
#
#	channeling technology for superior design and construction