Hi,
Currently I planning to write a compiler for a very complex grammaer
and I am investigating tools.
There are different tools available in the market .e.g yacc, bisson,
gold, lemnon ,cocoR and more.
The other option I am planning is writting compiler without tools so
that we can get good performnce.
Can you please help me what approach I should take to investigate tools
? Is you can give me some idea or direction then it would be really
useful.
Regards
Asheesh

Asheesh wrote:
Hi,

Currently I planning to write a compiler for a very complex grammar
and I am investigating tools.

If you'd tell more about the grammar and give a couple of examples,
it will be much easier to find the right tools.

There are different tools available in the market .e.g yacc, bisson,
gold, lemnon ,cocoR and more.

The other option I am planning is writting compiler without tools so
that we can get good performnce.

Well, most of the computation time of a compiler is spent in lexical
analyzer. the 2nd place is the backend, so I'm afraid that writing
compiler without tools wouldn't give you much better performance. For
improving a lexer, you can check the "perfect hash" functions.
BTW, bison is a dialect of yacc.

Can you please help me what approach I should take to investigate tools
? Is you can give me some idea or direction then it would be really
useful.

It heavily depends on the grammar of your language. Just two examples
are shown below.

1. C language: a very simple grammar, an existing parser can be found
for every existing tool. Not a context-free language, needs semantic
hacks for typedefs, pointer dereference.

2. English language: a bit more complicated grammar, usually needs
simultaneous translation on several levels, with information exchange
between all the levels.

Currently I planning to write a compiler for a very complex grammaer
and I am investigating tools.

There are different tools available in the market .e.g yacc, bisson,
gold, lemnon ,cocoR and more.

The other option I am planning is writting compiler without tools so
that we can get good performnce.

I'm not sure why you conclude that using tools yields worse
performance. There is reasonable evidence that tools can embody
efficient implementation techniques that many (most?) users are not
aware of, so the result is often more efficient than the user would
have produced. Even if the user can read up on efficient techniques
and implement them, a tool often gets you to the same point much
faster with less knowledge required. If I may be permitted a self
citation, see [1] for a study of the efficiency of generated compilers
compared to hand-coded ones.

There are many tools that enable easy creation of various kinds of
parsers (some of which you cite above). However, a more important
aspect is what other processing you plan to do. The parser usually
constitutes a fairly minor part of a full compiler, so I would advise
you to consider carefully what other tasks you plan to do (e.g. name
and type analysis, optimisation, code generation) and look at tools in
terms of the support they provide for those tasks.

the other hand, if you plan to do mostly parsing, then there is not
much to choose between the many tools out there. Two points for
comparison that might be relevant are:
- the method used by the parser generator (e.g., bottom-up table
driven vs top-down recursive descent), some folks prefer the latter
since the generated parsers are easier to understand, although many
of us never plan to read the generated code anyway
- the target language of the generator

Tony Sloane

[1] An evaluation of an automatically generated compiler, A M Sloane
ACM Transactions on Programming Languages and Systems (TPLAS)
Volume 17, Issue 5 (September 1995), 691 - 703

Hi,

Thanks a lot for your kind reply.

I am planning to write a Fortran compiler and for it I am just
evaluating various tools available in the market which can help me in
designing various modules lexical, semantic, parser, preprocessor etc.

As there are lots of tools in market and it will take lots of time to
evaluate all the tools so I need help of you guys who can atleast guide
me for known tools so that I can do investigation about certain tools
only.

Please let me know if my explanation is ok ? or u need some more
detailed one ?

regards
asheesh
[Fortran is hard to lex but easy to parse. I have front end for most of
Fortran 77 in on the compilers FTP site, with a hand-written C lexer and
a yacc parser. -John]

Hi,

Thanks a lot for your reply. I would be writing Fortran compiler from
the scratch and for various phases I am looking for best tools
available in the market so that I can write highly optimized compiler.

Can you suggest some tools for various phases so that I can investigate
them as per my requirement ?

currently I am investigating following tools:

1) Eli
2) Gold
3) Antlar
4) lex/yacc
5) coco R.

Can you help me now ?

Regards
Chads

Asheesh <asheeshc@noida.hcltech.comwrote:
I am planning to write a Fortran compiler and for it I am just
evaluating various tools available in the market which can help me in
designing various modules lexical, semantic, parser, preprocessor etc.

We have built lexers and parsers for Fortran 77 and Fortran 90 and many
other languages using the Cocktail Toolbox for compiler construction.
Besides a scaner generator and two parser generators the Cocktail Toolbox
contains tools for syntax trees, semantic analysis, and code generation.
The Fortran parsers are available.

Best regards

Dr. Josef Grosch

CoCoLab - Datenverarbeitung
Hoehenweg 6
77855 Achern
Germany

Phone : +49-7841-669144
Fax : +49-7841-669145
Email : grosch@cocolab.com
Internet: www.cocolab.com