>   Out of curiousity I wanted to see exactly how the different optimization
> flags in gcc affect the speed of povray (3.6.1).

	Thanks, that is right in line with what I've been doing for the past
14 months now  :-)

>   Because I didn't want to wait for 30-60 minutes for the standard benchmark,
> I just used scenes/advanced/abyss.pov instead.

	I also used this scene (for the fastpov2 study I hope to publish before
the end of the year) though with different settings.  Seems to get something
consistent with your results.

> * -O3 -march=pentium4 -ffast-math -mfpmath=sse -msse2
>   (1 min 26 secs, 1 661 452):
>   Total Time:    0 hours  5 minutes 13 seconds (313 seconds)

	Would be nice for completeness if you could also report results for
a binary without -msse2 (likely no difference with the above).

>   I noticed that the configure script of unix-pov3.6.1 did not add
> the "-ffast-math" option to the Makefiles. This is worthy of notice.

	Yes, it has been added for 3.6.2 quite some time ago already.

>   Note also how -minline-all-stringops (which the configure script adds)
> actually *slows* down the rendering a tiny bit.

	This is interesting.  Seems also in agreement with what has been
observed on the AMD64 recently (Christoph).  Looks like I have to try
this out too, though I don't really get why this can possibly make such
a difference...

	- NC

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