Date: Wed, 15 Sep 2004 16:27:51 -0700
From: William Lee Irwin III <wli@holomorphy.com>
To: Albert Cahalan <albert@users.sf.net>
Cc: linux-kernel mailing list <linux-kernel@vger.kernel.org>, ak@muc.de
Subject: Re: get_current is __pure__, maybe __const__ even
Message-ID: <20040915232751.GD9106@holomorphy.com>
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Andi Kleen writes:
>> Please CSE "current" manually. It generates
>> much better code on some architectures
>> because the compiler cannot do it for you.

On Wed, Sep 15, 2004 at 06:50:00PM -0400, Albert Cahalan wrote:
> This looks fixable.
> At the very least, __attribute__((__pure__))
> will apply to your get_current function.
> I think __attribute__((__const__)) will too,
> even though it's technically against the
> documentation. While you do indeed read from
> memory, you don't read from memory that could
> be seen as changing. Nothing done during the
> lifetime of a task will change "current" as
> viewed from within that task.

The fix needs to be made to gcc, not the kernel.


-- wli
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