theese numbers were quite interesting, could you please run one more? 
Try CFLAGS="-march=athlon-xp -O3 -finline-functions -ffast-math 
-foptimize-sibling-calls  -ansi -march=i686 -DCPU=686" for the  athlon-xp
 and see if it differs some or more from the output with march=i686

gcc 3.0.x had march=athlon
gcc 3.1 had march=athlon-tbird, athlon-xp, athlon-mp and athlon-4. I
havent dug any deeper to see just what is different between them, except
for some submodel changes.


antoher thing to be tested would be -mfpmath="sse,387" which will attempt
to use bothe the sse and the i387  fp engine at the same time, thus
doubling(!) the amount of registers accessible.  I've got a slight feeling
this may do some interesting things for applications like POV .

also, since we're not using debugging here, it should be considered to use
-fomit-frame-pointer on gcc, thus freeing up another register, not always
desirable or noticeable in desktop applications, but this is a "special
case" so it should be ok :)


Regards,
  Spider
    ...a memory...



On Tue, 11 Jun 2002 13:26:34 +0200, Thomas Willhalm wrote:

> Hello,
> 
> finally, I've found the time to compare the different compilations of 
> povray on a Pentium IV.  I used megapovplus and modified povbench.pov from 
> povray 3.5 beta to run on it.
> 
> Running time in seconds:
>                P-IV   Athlon
> gcc 2.95.3    13354    7035
> gcc 3.0.1     11319    6555
> gcc 3.1        8971    5901
> icc 6         15907    5679
> icc 6 IV      10589
> 
> "P-IV" is a Intel(R) Pentium(R) 4 CPU 1.60GHz
> running SuSE Linux with kernel 2.4.16-4GB
> 
> "Athlon" is a AMD Athlon(TM) XP 1500+ (1343.051 MHz)
> running SuSE Linux with kernel 2.4.10-4GB
> 
> Compiling options were:
> gcc 2.95.3  -O3 -finline-functions -ffast-math -ansi -march=i686 -DCPU=686
> gcc 3.0.1   -O3 -finline-functions -ffast-math -foptimize-sibling-calls 
> -ansi -march=i686 -DCPU=686
> gcc 3.1     -O3 -finline-functions -ffast-math -foptimize-sibling-calls 
> -ansi -march=i686 -DCPU=686
> icc 6       -O3 -tpp6  -xK -unroll -ip
> icc 6 IV    -O3 -tpp7  -xW -unroll -ip
> 
> The last version is optimized for Pentium-IV. That's why the binary doesn't 
> run on the Athlon.
> 
> Best regards
> Thomas

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