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Subject: Re: [RFC PATCH v2 1/4] tools/nolibc: x86-64: Use `rep movsb` for
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To: Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
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From: Ammar Faizi <ammarfaizi2@gnuweeb.org>
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On 2023/09/02 午後7:29, Alviro Iskandar Setiawan wrote:
> On Sat, Sep 2, 2023 at 1:38 PM Ammar Faizi wrote:
>> Ok, I'll do that.
> 
> Another micro-optimization. Since the likely case is the forward copy,
> make it the case that doesn't take the jump.
> 
> Pseudo C:
> if (unlikely(dst - src < n))
>          backward_copy();
> else
>          forward_copy();

Point taken.

-- 
Ammar Faizi