Hey:

On Tue, Jan 20, 2015 at 5:06 PM, Benjamin Coutu <ben.co...@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 <xinche...@zend.com>
> To: Benjamin Coutu <ben.co...@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.co...@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
>>
>



-- 
Xinchen Hui
@Laruence
http://www.laruence.com/

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