[antlr-interest] ANTLR 3.1 - Serious performance downgrade

[Dr. Michael Gerz]

Terence Parr schrieb:
>
> 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.

Are you going to provide a performance fix in the near future? 
Backgrading means recompiling my grammars (there are many of them in my 
project), because the API changed during summer.

Michael