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To: "php-dev" <internals@lists.php.net>, "Antony Dovgal" <antony@zend.com>
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Date: Fri, 10 Nov 2006 05:14:19 -0600
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Subject: Re: [PHP-DEV] zend_u_strtod() 400% speed up
From: php_lists@realplain.com ("Matt Wilmas")

Hi Antony,

----- Original Message -----
From: "Antony Dovgal"
Sent: Friday, November 10, 2006

> Hello all.
>
> I would like to propose a replacement for current zend_u_strtod()
implementation.
> The patch: http://tony2001.phpclub.net/dev/tmp/u_strtod.diff
>
> According to my tests, new implementation is faster in about 40 (forty)
times.
> The simple script below takes ~1 sec to run with the patch and ~40 seconds
without.

Cool. :-)  I'd just been thinking about zend_u_strtod() again -- if you see
my thread asking Andrei about the Unicode characters allowed as numbers...
I changed the function back in the summer to be about 8x faster by
converting FROM Unicode and using the regular zend_strtod(), but it was just
a quick hack, so maybe better that it wasn't applied!
http://realplain.com/php/zend_u_strtod.diff

BTW, your version would actually be 4000% faster, no? :-O


> The only question here is which locale to use for number
parsing/formatting.
> I used "en_US_POSIX" and it doesn't seem to create any new problems,
> though I'd like to hear your comments.

Since Andrei and README.UNICODE say only ASCII characters in en_US_POSIX
locale, I'd think you're right. :-)

I was thinking, now that I know only basic ASCII digits are allowed,
zend_u_strtod() could manually grab the valid [prefix of] numbers, put them
in a char[some_size] buffer and use the regular zend_strtod(), etc.  But it
doesn't seem like that would beat your version!

Just looking at the code again, I don't think it sets *endptr correctly with
a partial match (123.4foo)?  Is "pos" set to the number of chars scanned?

> -- 
> Wbr,
> Antony Dovgal

Matt