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From: Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Date: Sat, 2 Sep 2023 19:29:04 +0700
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Subject: Re: [RFC PATCH v2 1/4] tools/nolibc: x86-64: Use `rep movsb` for
 `memcpy()` and `memmove()`
To: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Cc: Willy Tarreau <w@1wt.eu>, =?UTF-8?Q?Thomas_Wei=C3=9Fschuh?= <linux@weissschuh.net>, 
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On Sat, Sep 2, 2023 at 1:38=E2=80=AFPM 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();

-- Viro