Subject: Re: [PATCH v2 10/30] Add x86-specific parity functions
To: Borislav Petkov <bp@suse.de>,
        One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
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 <20160406101300.GA13719@pd.tnic>
 <20160406113737.0b73bb40@lxorguk.ukuu.org.uk>
 <20160406105315.GB13719@pd.tnic>
Cc: zengzhaoxiu@163.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
        dvlasenk@redhat.com, akpm@linux-foundation.org, dvyukov@google.com,
        keescook@chromium.org, linux-kernel@vger.kernel.org
From: Zeng Zhaoxiu <zhaoxiu.zeng@gmail.com>
Message-ID: <5705DA47.1060902@gmail.com>
Date: Thu, 7 Apr 2016 11:55:51 +0800
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在 2016年04月06日 18:53, Borislav Petkov 写道:
> On Wed, Apr 06, 2016 at 11:37:37AM +0100, One Thousand Gnomes wrote:
>> Even that would still be wrong for the smaller parity values. The CPU
>> supports 8bit parity directly going back to the 8086 so the
>> implementation for 8bit and I think 16bit is still wrong.
> I was objecting to the unnecessary replication of the hweight/popcnt
> glue.
>
> And yes, one could look up the definition of the parity flag on x86 and
> then base the implementation of all those smaller ones on that as the
> hardware does it for one practically for free there.
>
> :-)
>

SETcc (SETPO etc.) added since 80386, is this a problem?