gcc option for e500v2

[Liu Yu-B13201]

Hi all,

I am using the cs-released gcc-4.1.78 which configured for e500v2. It
has some special optimization options such as "-mcpu=8548 -mspe=yes
-mabi=spe -mfloat-gprs=double". Can anyone tell me what effect they can
make?

In fact, if these optimization options are necessary while building
package, I need to configure them set default. 


BTW, option "-m64" is not support on my target. When use this option,
the error info is like below:

> powerpc-linux-gnuspe-gcc -m64  test.c
test.c:1: error: -m64 not supported in this configuration

Does anyone know how to enable it?

Best Regards.
 
Yu