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References: <20190405072630.E2A025FB14@mx.zeyos.com>
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Date: Fri, 5 Apr 2019 11:00:03 +0200
Message-ID: <CAFPFaMLEoWJoScUVbBj6xEzQ2hD5gtnnKbmzw_XA=CmMj+H--Q@mail.gmail.com>
To: Benjamin Coutu <ben.coutu@zeyos.com>
Cc: PHP internals <internals@lists.php.net>, Dmitry Stogov <dmitry@zend.com>, 
	Nikita Popov <nikita.ppv@gmail.com>
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Subject: Re: [PHP-DEV] Optimize zend_string equality check with hash key
From: george.banyard@gmail.com ("G. P. B.")

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On Fri, 5 Apr 2019, 09:26 Benjamin Coutu, <ben.coutu@zeyos.com> wrote:

> Hello,
>
> I was surprised to find out that equality checks on zend_string do not
> take advantage of the fact that in many cases we have a hash key available
> that can be utilized in a quick bailout path without having to resort to a
> costly `memcmp` on the value.
>
> I recommend to modify `zend_string_equal_content` like so:
>
> static zend_always_inline zend_bool zend_string_equal_content(zend_string
> *s1, zend_string *s2)
> {
>   if (ZSTR_LEN(s1) != ZSTR_LEN(s2)) {
>     return 0;
>   }
>
>   if (ZSTR_H(s1) && ZSTR_H(s1) != ZSTR_H(s2)) {
>     return 0;
>   }
>
>   return zend_string_equal_val(s1, s2);
> }
>
> Thoughts?
>
> --
>
> Benjamin Coutu
> ben.coutu@zeyos.com
>

Best idea would be to do a PR on the GitHub repo.

Best regards

George Peter Banyard

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