[antlr-interest] ANTLR 3.1 - Serious performance downgrade

Terence Parr parrt at cs.usfca.edu
Sun Aug 17 13:24:54 PDT 2008

On Aug 17, 2008, at 1:19 PM, Benjamin Niemann wrote:

> Hi Michael,
> there has been a major change to the implementation of the
> TokenRewriteStream. I quick look at the code suggests, that
> TokenRewriteStream.reduceToSingleOperationPerIndex() is O(n^2), where
> n is the number of rewrites - and it is called for each toString call.
> Did you do some profiling to find the method that takes most of the
> time?

Hi.  Yep, n^2 but figured there aren't THAT many changes...decided  
that I'd go for actually correct functionality first...it was horribly  
broken except for some common cases before.

I just saw your earlier post...ooops.  Sorry about that.  I guess I  
need to build an index for that code.  Shit.  Likely you can backgrade  
to earlier version fairly easily for now.


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