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