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Re: More __get_user_asm_ll32 ...

To: ralf@linux-mips.org
Subject: Re: More __get_user_asm_ll32 ...
From: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Date: Wed, 14 Feb 2007 01:06:15 +0900 (JST)
Cc: vagabon.xyz@gmail.com, linux-mips@linux-mips.org
In-reply-to: <20070213133251.GA7518@linux-mips.org>
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <20070213133251.GA7518@linux-mips.org>
Sender: linux-mips-bounce@linux-mips.org
On Tue, 13 Feb 2007 13:32:51 +0000, Ralf Baechle <ralf@linux-mips.org> wrote:
> __get_user_asm_ll32 contains a junk move %0, $0 left over from an older
> version of the code.  Ignoring fixups code and data this instruction
> inflates the normal path in __get_user() by 50% which may explain much of
> the size and performance you have meassures.  It also always clears
> the error return, iow. __get_user_asm_ll32(..., &<something 64-bit>)
> would never have returned an error.  ARGH.

Why is it clears the error return?  The "3:" label is just after the
junk move.

---
Atsushi Nemoto

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