libgcc: strange optimization

[Andrew Haley]

On 08/04/2011 01:19 AM, Hans-Peter Nilsson wrote:

> To make sure, it'd be nice if someone could perhaps grep an
> entire GNU/Linux-or-other distribution including the kernel for
> uses of asm-declared *local* registers that don't directly feed
> into asms and not being the stack-pointer?  Or can we get away
> with just saying that local asm registers haven't had any other
> documented meaning for the last seven years?

It's the sort of thing that gets done in threaded interpreters,
where you really need to keep a few pointers in registers and
the interpreter itself is a very long function.  gcc has always
done a dreadful job of register allocation in such cases.

Andrew.