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From: Andreas Schwab <schwab@redhat.com>
To: "David Laight" <David.Laight@ACULAB.COM>
Cc: "David Daney" <ddaney@caviumnetworks.com>,
        "Coly Li" <bosong.ly@taobao.com>, Wang Cong <xiyou.wangcong@gmail.com>,
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        linux-kernel@vger.kernel.org, Yong Zhang <yong.zhang0@gmail.com>
Subject: Re: [PATCH 2/7] PowerPC: add unlikely() to BUG_ON()
References: <4D41B213.4070606@caviumnetworks.com>
	<AE90C24D6B3A694183C094C60CF0A2F6D8AC2D__37237.0892241181$1296205746$gmane$org@saturn3.aculab.com>
X-Yow: Clear the laundromat!!  This whirl-o-matic just had a nuclear meltdown!!
Date: Fri, 28 Jan 2011 11:14:16 +0100
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	(David Laight's message of "Fri, 28 Jan 2011 09:05:59 -0000")
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"David Laight" <David.Laight@ACULAB.COM> writes:

> Also, as (I think) in some of the generated code quoted,
> use of __builtin_expect() with a boolean expression can
> force some versions of gcc to generate the integer
> value of the expression

That's more likely a side effect of the definition of likely/unlikely:
they expand to !!(x).

Andreas.

-- 
Andreas Schwab, schwab@redhat.com
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