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Date:   Tue, 8 Oct 2013 14:15:46 +0200
From:   Ralf Baechle <ralf@linux-mips.org>
To:     Markos Chandras <markos.chandras@imgtec.com>
Cc:     linux-mips@linux-mips.org,
        Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Subject: Re: [PATCH] MIPS: Print correct PC in trace dump after NMI exception
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References: <1381232371-25017-1-git-send-email-markos.chandras@imgtec.com>
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On Tue, Oct 08, 2013 at 12:39:31PM +0100, Markos Chandras wrote:

> +	/*
> +	 * Clear ERL - restore segment mapping
> +	 * Clear BEV - required for page fault exception handler to work
> +	 */
> +	mfc0	k0, CP0_STATUS
> +	ori     k0, k0, ST0_EXL
> +	lui     k1, %hi(~ST0_BEV)
> +	ori     k1, k1, %lo(~ST0_ERL)

Why not:

	li	k1 ~(ST0_BEV | ST0_ERL)

If you were afraid gas might use $1 expanding this macro instruction - no,
it won't.  A belt & suspenders approach might be to drop in a ".set noat";
it would make the assembler throw an error if should ever see the need to
use $1.

  Ralf