27-Sep-2013 02:00, JR пишет:
I'm working on a toy IRC bot. Much of the logic involved is translating
the incoming raw IRC string into something that makes sense (so now I
have two problems, etc). But I managed to cook up a regex that so far
seems to work well. Time for callgrind!
Grouped by source file, most time is spent in regex.d (as would seem
natural) but more time is spent in gc.d than I would have expected.
Looking at the callgraph I see that there's a curious amount of calls to
_d_arrayliteralTX from (around) where the regex matching is done.
(There's some inlining going on.)
Example: http://dpaste.dzfl.pl/3932a231 (needs dmd head)
And the answer is - don't use ENUM with ctRegex.
The problem is that ctRegex returns you a pack of datastructures (=arrays).
Using them with enum makes it behave as if you pasted them as array
literals and these do allocate each time.
TL;DR: use static and/or auto with ctRegex not enum.
--
Dmitry Olshansky
