Yes, you should read the machine description documentation http://gcc.gnu.org/onlinedocs/gccint/index.html#toc_Machine-Desc, in particular register usage http://gcc.gnu.org/onlinedocs/gccint/Registers.html#Registers and then hack the x86 backend. You might just be able to edit the fixed registers for this. On Mon, Nov 4, 2013 at 3:59 AM, David Kaplan <davkaplan@xxxxxxxxx> wrote: > 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
