From: Junio C Hamano <gitster@pobox.com>
Date: Sat, 29 Dec 2007 19:32:48 GMT
Subject: Re: [PATCH] Speedup prefixcmp() common case
Message-ID: <7v63yhb8kf.fsf@gitster.siamese.dyndns.org>
In-Reply-To: <e5bfff550712291001q5f246ceah6700b98308fb96f1@mail.gmail.com>

"Marco Costalba" <mcostalba@gmail.com> writes:

> diff --git a/git-compat-util.h b/git-compat-util.h
> index 79eb10e..e26b684 100644
> --- a/git-compat-util.h
> +++ b/git-compat-util.h
> @@ -398,6 +398,10 @@ static inline int sane_case
>
>  static inline int prefixcmp(const char *str, const char *prefix)
>  {
> +	// shortcut common case of a single char prefix
> +	if (prefix && *(prefix + 1) == '\0' && str)
> +		return *str - *prefix;
> +

Why isn't it like this?

	if (!prefix[1])
		return *str - *prefix;

>  	return strncmp(str, prefix, strlen(prefix));
>  }
>
> -- 
> 1.5.4.rc2-dirty