From: "H. Peter Anvin" <hpa@zytor.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: kernel list <linux-kernel@vger.kernel.org>,
linuxppc-dev@ozlabs.org, paulus@samba.org,
Pavel Machek <pavel@ucw.cz>
Subject: Re: register long sp asm("r1") incorrect
Date: Mon, 15 Feb 2010 14:15:17 -0800 [thread overview]
Message-ID: <4B79C775.1050903@zytor.com> (raw)
In-Reply-To: <1266267898.16346.135.camel@pasglop>
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.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
next prev parent reply other threads:[~2010-02-15 23:13 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-09 15:24 register long sp asm("r1") incorrect Pavel Machek
2010-02-11 5:31 ` Benjamin Herrenschmidt
2010-02-15 7:34 ` Pavel Machek
2010-02-15 19:59 ` Benjamin Herrenschmidt
2010-02-15 20:28 ` Pavel Machek
2010-02-15 21:04 ` Benjamin Herrenschmidt
2010-02-15 22:15 ` H. Peter Anvin [this message]
2010-02-18 22:57 ` Pavel Machek
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