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From: Thomas Monjalon <thomas.monjalon@6wind.com>
To: "Xie, Huawei" <huawei.xie@intel.com>
Date: Tue, 30 Sep 2014 16:51:10 +0200
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Cc: dev@dpdk.org, Hayato Momma <h-momma@ce.jp.nec.com>
Subject: Re: [dpdk-dev] [memnic PATCH v2 6/7] pmd: add branch hint in
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2014-09-30 14:38, Xie, Huawei:
> > -		if (++next >= MEMNIC_NR_PACKET)
> > +		if (unlikely(++next >= MEMNIC_NR_PACKET))
> 
> On IA,  compiler can use add, cmp and cmov to avoid branch.
> But If MEMNIC_NR_PACKET is always power of 2, 
> 	it is better just next = (next + 1) & (MEMNIC_NR_PACKET - 1)

Power of 2 is not enforced for MEMNIC_NR_PACKET.

-- 
Thomas