Best mcpu option for amcc440 with fpu ?

[Segher Boessenkool]

>    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 ?

Dunno.  You need to hunt down more details first:

-- Run a profiler (oprofile, gprof) to pinpoint one
specific (preferably smallish) piece of code that has
a huge slowdown;
-- Look at the generated assembler code for that routine
to see what's up;
-- Try to figure out why that happened, or report back
here.


Segher