Custom x86 ABI

[David Kaplan <davkaplan@xxxxxxxxx>]

Hi

I've just build a cross-compiler with the i586-elf target which I need
for my project.
I was wondering: is there a way to build a custom ABI such that the
EBX (or any other register) is never used by GCC?
If so, how do I go about doing it?

Thanks,
David