register long sp asm("r1") incorrect

Pavel Machek pavel at ucw.cz
Fri Feb 19 09:57:11 EST 2010


On Mon 2010-02-15 14:15:17, H. Peter Anvin wrote:
> On 02/15/2010 01:04 PM, Benjamin Herrenschmidt wrote:
> > 
> > It's true that most other use of it we have are global scope (local_paca
> > in r13, glibc use of r2/r13, etc...) afaik, but since r1 itself is the
> > stack pointer always, I think they pretty much guarantee it works.
> > 
> 
> It should work, because r1, being the stack pointer, is already marked a
> reserved register in gcc.
> 
> The reference Pavel is citing bascially states that gcc won't globally
> reserve the register, which is true, but it is already reserved anyway.

Ok, thanks for clarification.

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