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Date: Thu, 22 Jan 2015 11:39:11 +0800
From: Linhaifeng <haifeng.lin@huawei.com>
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Subject: [dpdk-dev] some questions about  rte_memcpy
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#define rte_memcpy(dst, src, n)              \
	((__builtin_constant_p(n)) ?          \
	memcpy((dst), (src), (n)) :          \
	rte_memcpy_func((dst), (src), (n)))


Why call memcpy when n is constant variable?
Can i change them to the follow codes?

#define rte_memcpy(dst, src, n)              \
    {   \
        int num = n;    \
	rte_memcpy_func((dst), (src), (num)))   \
    }


-- 
Regards,
Haifeng