Marcus Boerger wrote:
Hello Rasmus,
not a thing for 5.1 or 4.4 but in 5.2 we could change to a case
insensitive comparison function. That would allow us to change nearly
all of strcasecmp to memcmp. And in may cases it means one less
allocation. And it also means a lot of less code. The casinsensitive
comparision is pretty easy because we can use a 256 byte translation
table that can be provided as a static const table. On a X86 systems
we could also provide that in assembler. That would give us the
possibility to use the XLAT instruction that would otherwise not be
used (maybe newer optimizing compiler know about it though).
Maybe it is worse trying to bring it in and checking how much slower
we are getting with it. If the numbers look promising we could go for
the change then.
A word on HEAD/Unicode. If we use a case insensitivity semantics where
only the normal ascii characters are lowercased we can use the same
table based approach.
Anyway from looking at the output the best optimization was brought up by
you already. Using jit for the ap_* stuff.
Well, that doesn't come anywhere near the radar here actually. The
300k+ strcasecmp calls are coming from the qsort in Apache, not from
PHP. Even then, 300k strcasecmp calls is minor here. So I doubt you
could even measure the effect of that change.
-Rasmus
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
