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Subject: Re: Optimize zend_string equality check with hash key
From: ajf@ajf.me (Andrea Faulds)
Message-ID: <php.internals-105152@news.php.net>

Hi Benjamin,

Benjamin Coutu wrote:
>    if (ZSTR_H(s1) && ZSTR_H(s1) != ZSTR_H(s2)) {
>      return 0;
>    }

Should that not be like this?:

     if (ZSTR_H(s1) && ZSTR_H(s2) && ZSTR_H(s1) != ZSTR_H(s2)) {

It would be possible the other string also has no hash value.

Otherwise this sounds sensible to me, but it is also so obvious that I 
was assuming until now that PHP does it, so maybe someone else knows a 
reason why we don't? (Maybe it's just not worth the extra branches?)

Thanks,
Andrea