Re: Understanding C parsers generated by GNU Bison

[Hans Aberg]

On 14 Sep 2006, at 16:22, Satya wrote:

> I had been studying Bison for a while now, and I came up with this  
> small
> writeup on the internals of a parser generated by Bison 2.3. I  
> described the
> tables and operation of a bare yyparse() (sans the more gory  
> details like
> stack relocation and error handling).
>
> http://cs.uic.edu/~spopuri/cparser.html
>
> I have done this in the hope that it will be useful for anyone who  
> wants to
> change the skeleton/ hand optimize the generated parser or simply  
> want to
> understand whats going on. It would be great if anyone  
> knowledgeable about
> the current yacc.c skeleton can go through this and pass me
> comments/corrections etc.

I think it would be good to include something like that in the Bison  
distribution, because from time to time, there have requests for in  
the Bison lists. Then, the best answer so far has been the RTFC by  
Akim Demaille. :-)

The parser used in LR is evidently called "push-down" automaton. See  
the book by Waite & Goos, "Compiler Construction". Dick Grune has  
also written a parsing book free online; I think it is mentioned in  
the comp.compilers FAQ.

  Hans Aberg