register used as both FP and GP register when -Os switch used

I'm porting gcc 4.6.2 to a 16 bit CPU that has four GP registers. I've chosen to allocate R3 as the frame pointer when one is needed. In line with GCC Internals info on FIXED_REGISTERS ("except on machines where that can be used as a general register when no frame pointer is needed") I have no

register used as both FP and GP register when -Os switch used

I'm porting gcc 4.6.2 to a 16 bit CPU that has four GP registers. I've chosen to allocate R3 as the frame pointer when one is needed. In line with GCC Internals info on FIXED_REGISTERS ("except on machines where that can be used as a general register when no frame pointer is needed") I have no