bstone wrote:
> about the sse comment
> gcc3.2 (and 3.1) work with sse/sse2, but there are still a ton of x87 calls
> based on the way the code is laid out.
> unfortunately based on my testing the windows binary is still at least 10%
> faster than the best binary I was able to make with gcc 3.2.
> I think the code needs to be restructured to get a big speed boost.

There must be some stuff in the Windows official binary that takes advantage
of the Pentium specifically. Either that or gcc 3.1 likes Athlons better :P

On my Athlon XP 1900+ I get consistently faster renders with my custom 
Athlon
build of POV-Ray 3.5 vs the Windows official binary. The difference is very
small and nothing to get excited about but it certainly isn't 10% slower.
Here's a couple of render times from some tests I did this morning:

benchmark.pov
-------------
Windows official binary   = 26m 24s (1584s)
Athlon targeted gcc build = 25m  7s (1507s)

balcony.pov
-----------
Windows official binary   = 8m 14s (494s)
Athlon targeted gcc build = 7m  3s (423s)

The compiler flags used to make the Athlon targeted build using gcc 3.1 
were:

-O3 -s -mcpu=athlon -march=athlon -finline-functions -ffast-math \
-fomit-frame-pointer -Wall -funroll-loops -fexpensive-optimizations \
-malign-double -foptimize-sibling-calls -minline-all-stringops 
$(NOMULTICHAR)

I don't know if this sheds any light on anything and I'm certainly no
expert! I just found it kind of interesting.

-Roz

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