Global registers

[Will Newton <will@misconception.org.uk>]

I am the maintainer of clisp, a package that has had portability a problem on 
sparc. I have found a solution to the problem, but it involves disabling the 
allocation of various globals to registers. clisp uses the registers g4-g7 to 
store such things as it's stack pointer. These registers are obviously being 
clobbered somewhere. Are there any other registers available that could be 
used? I suspect not... Or can anyone point me to documentation on when these 
registers need to be saved?

Thanks,