Re: Re: Improvements to array.c code base

Sorry, your right of course as not preserving keys only applies to numeric indices. ========== Original ========== From: Xinchen Hui <xinchen.h@zend.com> To: Benjamin Coutu <ben.coutu@zeyos.com> Date: Tue, 20 Jan 2015 10:13:04 +0100 Subject: Re: [PHP-DEV] Re: Improvements to array.c code base Hey: On Tue, Jan 20, 2015 at 5:06 PM, Benjamin Coutu <ben.coutu@zeyos.com> wrote: > Hi, > > Regarding ARRAY_SLICE(..., preserve_keys=false) my whole point was that the check for > non-numeric key inputs is not necessary if preserve_keys is false. > It should basically be analogue to array_values(), but of course respecting the offset and > length boundaries. I am not sure I understood your point. even if preserve_keys is false, it still use string key if origin is string key. > > One question regarding FAST_ZPP: Why is it not used more often, especially in the satndard > libraries? Is there some particular drawback? I'd like to understand. hmm, https://wiki.php.net/rfc/fast_zpp :) thanks > > Thanks, > > Ben > > ========== Original ========== > From: Xinchen Hui <xinchen.h@zend.com> > To: Benjamin Coutu <ben.coutu@zeyos.com> > Date: Tue, 20 Jan 2015 09:53:38 +0100 > Subject: [PHP-DEV] Re: Improvements to array.c code base > > > > Hey: > > > On Tue, Jan 20, 2015 at 4:30 PM, Benjamin Coutu <ben.coutu@zeyos.com> wrote: >> Hi Dmitry, >> >> I was doing some code review of ext/standard/array.c and have recognized some potential for >> a few performance improvements: >> >> === ARRAY_SLICE(..., preserve_keys=false) === >> >> array_slice() can always construct a packed array if preserve_keys is false, restricting it >> to inputs with packed flag does not make much sense. >> Removing the check for packed inputs on line 2376 would improve performance if used on >> non-packed inputs with the default preserve_keys=false. > This is check for non-numeric key inputs > >> Furthermore, ZEND_HASH_FOREACH_VAL should be used instead of ZEND_HASH_FOREACH_NUM_KEY_VAL >> on line 2379. > yeah, I will fix it. >> It also think range() should use FAST_ZPP as it is a basic language feature (other >> languages even have extra operators for it, e.g. [0..10]) >> >> === RANGE(...) === >> >> range() always returns a numerically indexed array [0..count-1]. The resulting array >> therefore should be constructed as a packed array (ZEND_HASH_FILL_PACKED+ZEND_HASH_FILL_ADD instead >> of zend_hash_next_index_insert_new). >> >> === ARRAY_FILL(start_key=0, ...) >> === >> >> Just like with range(), array_fill() always returns a numerically indexed array >> [0..count-1] if start_key is 0. In this special but very common case the resulting array can be >> constructed as a packed array (ZEND_HASH_FILL_PACKED+ZEND_HASH_FILL_ADD instead of >> zend_hash_next_index_insert_new). >> Another common case is for start_key to be 1. One could refine the proposed packed-array >> branch to just set the first bucket to undefined in this case. >> >> === COUNT(...) === >> >> count() is so ubiquitous! Giving it an opcode and making it part of the VM seams >> reasonable.. >> >> Please let me know your thoughts. > hmm, we currently do optimization based on profile against some real > life apps, like wordpress. > > range and array_fill etc doesn't used very common.. so I didn't look into it.. > > thanks for the advise, I will take a look . > > thanks >> >> Cheers, >> >> Ben >> >> -- >> >> Benjamin Coutu >> Zeyon Technologies Inc. >> http://www.zeyos.com >> >