Question on GCC register optimization.

[Henri Cloetens]

Hello All,

I am still working on a GCC backend for a custom processor.

When running the compiler with following flags:

gcc -O3 -S -c -fcprop-registers -frename-registers,

I find out it does not optimize the allocation of the registers.
The routine used is simple function, and what I see is that
it allocates excess registers, in short, it does not optimize
register usage. I would expect it:
 Â - performs register lifetime analysis
 Â - performs register renames as to minimize cost.

Question is: I think I invoked the 2 optimizers. Could
 Â  anybody point me to documentation on them ?. I think
 Â  I am missing some target 'hooks', but I have no idea what it is.

Best Regards,

Henri.