Re: [BK+PATCH] remove __constant_memcpy

J.A. Magallon (jamagallon@able.es)
Fri, 18 Apr 2003 00:58:50 +0200

On 04.17, Jeff Garzik wrote:
> On Thu, Apr 17, 2003 at 09:07:45AM -0700, Linus Torvalds wrote:
[...]
>
> #define memcpy(t, f, n) \
> (__builtin_constant_p(n) ? \
> __constant_memcpy3d((t),(f),(n)) : \
> __memcpy3d((t),(f),(n)))
>

Do you know if this is more efficient ? :

__builtin_choose_expr(__builtin_constant_p(n), ... , ....)

Perhaps ?: reaches runtime, and __builtin doesn't.

-- 
J.A. Magallon <jamagallon@able.es>      \                 Software is like sex:
werewolf.able.es                         \           It's better when it's free
Mandrake Linux release 9.2 (Cooker) for i586
Linux 2.4.21-pre7-jam1 (gcc 3.2.2 (Mandrake Linux 9.2 3.2.2-5mdk))
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