From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH v3] skip_prefix: rewrite so that prefix is scanned once
Date: Mon, 03 Mar 2014 15:35:30 -0800
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Cc: Siddharth Goel <siddharth98391@gmail.com>, git@vger.kernel.org,
	sunshine@sunshineco.com
To: David Kastrup <dak@gnu.org>
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In-Reply-To: <87bnxmkguw.fsf@fencepost.gnu.org> (David Kastrup's message of
	"Tue, 04 Mar 2014 00:22:15 +0100")
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David Kastrup <dak@gnu.org> writes:

> How about a function body of
>
> 	do {
>         	if (!*prefix)
>                 	return str;
>         } while (*str++ == *prefix++);
>         return NULL;
>
> I'm not too fond of while (1) and tend to use for (;;) instead, but that
> may again partly be due to some incredibly non-optimizing compiler back
> in the days of my youth.  At any rate, the do-while loop seems a bit
> brisker.

I do not have strong preference between "while (1)" and "for (;;)",
but I tend to agree

	for (;; prefix++, str++) {
		if (!*prefix)
			return str;
		if (*str != *prefix)
			return NULL;
	}

may be easier to read than what I suggested.  Your do-while loop is
concise and very readable, so let's take that one (I'll forge your
Sign-off ;-)).

I haven't looked at the generated assembly of any of these, though.