linux-kernel - Re: [PATCH 2/2] x86/entry/64: use xorl for register clearing

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Message-ID: <20180214182716.GA5918@isilmar-4.linta.de>
Date:   Wed, 14 Feb 2018 19:27:16 +0100
From:   Dominik Brodowski <linux@...inikbrodowski.net>
To:     Alexey Dobriyan <adobriyan@...il.com>
Cc:     linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] x86/entry/64: use xorl for register clearing

On Wed, Feb 14, 2018 at 09:21:12PM +0300, Alexey Dobriyan wrote:
> > -	xorq    %r8, %r8	/* nospec   r8 */
> > +	xorl	%r8d, %r8d	/* nospec   r8 */
> 
> The suffix should be simply dropped as operand size is unambigious.
> It is just one more character than necessary on the screen.

No strong feelings about this issue, but I prefer it to be explicit. And
that's what seems to be the standard in arch/x86/entry/ .

Thanks,
	Dominik