Optimize the wptexturize() Loop

[miqrogroove]

Following on #28575, there are some more things we can do to make this core code run faster:

The ampersand replacement pattern is running inside the loop for no apparent reason. We can get an overall 10% performance boost just by moving that one pattern to after the loop.

_wptexturize_pushpop_element() may be unnecessarily running regex code that could be replaced with simple string searches, for up to 7% performance boost.

Any opportunity to remove or consolidate the $dynamic patterns will improve performance by about 4% per pattern removed.

[miqrogroove]

First pass at optimizing ampersands and the element stack.

[miqrogroove]

Second pass after testing.

[miqrogroove]

Minimize the stack logic a bit more for a clean look.

[dllh]

I ran my prior tests from #28575 against trunk and with the second draft of the patch applied, and it's a nice improvement. My test is pretty blunt and not granular, but doing 10 iterations of wptexturize() for a 1MB post, trunk does it in around 6.2 seconds, and the patch shaves about a second off that time. More granular profiling like what you did on the other ticket will of course be more useful than my test. Seems like a nice step forward, though!

[miqrogroove]

Also fix ampersand pattern to match things like &# in text.

[miqrogroove]

Need to add tests for more things like &# and check if there is already a ticket for that.

[miqrogroove]

Allow various entity references.

[miqrogroove]

Update unit tests.

[miqrogroove]

fwiw, I also attempted to consolidate some of the $dynamic patterns by using preg_replace_callback, but the overhead for that function is so high that it negates most of the benefit of running fewer patterns.

In miqro-28623.6.patch:

• Take the ampersand pattern out of the loop for speed.
• Fix old bugs in the ampersand pattern.
• Refactor _wptexturize_pushpop_element() without PCRE for speed.
• Update unit tests.

[wonderboymusic]

In 28831:

Optimize the wptexturize() loop:

• Take the ampersand pattern out of the loop for speed.
• Fix old bugs in the ampersand pattern.
• Refactor _wptexturize_pushpop_element() without PCRE for speed.
• Update unit tests.

Props miqrogroove.
Fixes #28623.

[miqrogroove]

dllh: See #28724 for new work. I'd like to know if you can confirm another 3x speed improvement. :)