In article <3E4### [at] freefr> , Nicolas Calimet <pov### [at] freefr>
wrote:

> SYSTEMS TESTED
> ==============
>
>  I'm not root on any machine I have access to, so all softwares
> I install are placed under my home directory using the --prefix option,
> and an up-to-date environment variable LD_LIBRARYxx_PATH for loading the
> shared libraries at runtime.

Hi,

If the platform is PowerPC (not to be confused with IBMs Power3 or Power4
also the instruction set is identical), I would suggest the following
platform specific options should be a good choice in *addition* to generic
optimization settings when using gcc on PowerPC:

-mpowerpc -mcpu=750 -mtune=7450 -mmultiple -mstring -mfused-madd

Note that the different parameters for mcpu and mtune are intentional:

The PPC 7450 processor has a much longer pipeline and thus scheduling for
that pipeline always yields good results even on processors with a shorter
pipeline.  On the other hand, most PowerPC processors only support the
instructions also found in the PPC 750 processor (aka G3).  That is why it
is selected in the mcpu parameter.  Using 7450 (aka G4+) in mcpu would make
the code incompatible with anything prior to the PPC 7400 (aka G4).  To be
precise, the vector instructions are new in the four digit model number
PowerPC processors (aka G4), but gcc cannot (as of February 2003) use them
automatically anyway! [trf]

If you want, add this to the makefile as note for those options to avoid
questions.

    Thorsten

____________________________________________________
Thorsten Froehlich
e-mail: mac### [at] povrayorg

I am a member of the POV-Ray Team.
Visit POV-Ray on the web: http://mac.povray.org

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