[antlr-interest] Perfomance question re bit iterator

Terence Parr parrt at cs.usfca.edu
Tue Nov 16 14:52:48 PST 2004



On Nov 16, 2004, at 2:12 PM, ron_bennatan wrote:
> We've been doing some performance testing and when running gprof we
> see that around 40% of the time is in MismatchTokenException and
> specifically in std::_Bit_iterator std::_copy.
>
> Can anyone shed some light as to what exactly MismatchTokenException
> is, when it is raised (we think we know - but are not sure) and what
> we can do to reduce the run time? Also, are there any tips as to how
> to reduce the number of copies and anything else that can reduce the
> number of these exceptions and copies.

My guess is that the MismatchTokenException is due to backtracking.  Do 
you use lots of syntactic predicates?

Ter
--
CS Professor & Grad Director, University of San Francisco
Creator, ANTLR Parser Generator, http://www.antlr.org
Cofounder, http://www.jguru.com
Cofounder, http://www.knowspam.net enjoy email again!





 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/antlr-interest/

<*> To unsubscribe from this group, send an email to:
    antlr-interest-unsubscribe at yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/
 





More information about the antlr-interest mailing list