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Date:   Fri, 5 Aug 2022 11:42:07 +0200
From:   Joerg Roedel <jroedel@suse.de>
To:     David Laight <David.Laight@aculab.com>
Cc:     'Kanna Scarlet' <knscarlet@gnuweeb.org>,
        Borislav Petkov <bp@alien8.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        "x86@kernel.org" <x86@kernel.org>,
        Ard Biesheuvel <ardb@kernel.org>,
        Bill Metzenthen <billm@melbpc.org.au>,
        Brijesh Singh <brijesh.singh@amd.com>,
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        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
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Subject: Re: [PATCH 1/1] x86: Change mov $0, %reg with xor %reg, %reg
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References: <20220804152656.8840-1-knscarlet@gnuweeb.org>
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On Fri, Aug 05, 2022 at 09:26:02AM +0000, David Laight wrote:
> Use "xor %rax,%rax" instead of "xor %eax,%eax" to save
> the 'reg' prefix.

Also, some places explicitly use the mov variant to zero a register
without touching rflags. Please be careful to not change those.

Regards,

-- 
J?rg R?del
jroedel@suse.de

SUSE Software Solutions Germany GmbH
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