Best mcpu option for amcc440 with fpu ?

[Patrice Bouchand]

Hello,

   I'm having trouble trying to find the best
compiling
 option for amcc440 with fpu. I'm using a genuine 
fedora core 6 ppc distro (gcc4.1.1). It seems that 
using mcpu=440 gives better results than -mcpu=440fp, 
even with floating point code ? What could be wrong on

my platform to give such a result ?


The test :
mandelbrot.c is available here:
http://magnux.free.fr/gcc/mandelbrot.c

--------------------
-bash-3.00# gcc -O2 -mcpu=440fp ./mandelbrot.c -o
./mandelbrot && time ./mandelbrot 

real    1m15.016s
user    1m14.988s
sys     0m0.024s

-bash-3.00# gcc -O2 -mcpu=440 ./mandelbrot.c -o
./mandelbrot && time ./mandelbrot

real    0m39.606s
user    0m39.552s
sys     0m0.028s

-bash-3.00# gcc -O2 -msoft-float ./mandelbrot.c -o
./mandelbrot && time ./mandelbrot

real    0m39.577s
user    0m39.544s
sys     0m0.032s

-bash-3.00# gcc -O2 ./mandelbrot.c -o ./mandelbrot &&
time ./mandelbrot

real    1m15.059s
user    1m14.996s
sys     0m0.060s



	

	
		
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