VHDL language grammar

[titi]

I am interested to know what are the different grammars for VHDL language.

Are there any parser which can parse every vhdl file, written in
whatever VHDL dialect (87, 93)?

 

[HT-Lab]

I am interested to know what are the different grammars for VHDL language.

Are there any parser which can parse every vhdl file, written in whatever
VHDL dialect (87, 93)?

Yes, have a look here
http://tams-www.informatik.uni-hamburg.de/vhdl/vhdl.html

Hans
www.ht-lab.com

 

[Colin Paul Gloster]

In timestamped Thu, 01
Mar 2007 20:07:24 GMT, "HT-Lab" <[email protected]> posted:

I am interested to know what are the different grammars for VHDL language.

Are there any parser which can parse every vhdl file, written in whatever
VHDL dialect (87, 93)?

Yes, have a look here
http://tams-www.informatik.uni-hamburg.de/vhdl/vhdl.html

Hans"


Perhaps the VHDL-AMS JavaCC file from
WWW.TI.Informatik.Uni-Frankfurt.De/grimm/hybrid.html
might be different to the one from
HTTP://home.WTAL.De/software-solutions/vhdl-parser/
but the one in a university is not hyperlinked to from
TAMS-WWW.Informatik.Uni-Hamburg.De/vhdl/vhdl.html
..

All of these may be of some use, but most and probaly all of them may
have issues.

It is claimed on
WWW-DT.E-Technik.Uni-Dortmund.De/~mvo/vaul/
:"[..]

[..] types have been checked (excluding subtype constraints).

[..]"

The YACC grammar in
TAMS-WWW.Informatik.Uni-Hamburg.De/vhdl/tools/uc_vhdlgrammar.Z
is dated 1990.

The URLs given for the parser written in Prolog are out of date. A
newer relevant URL is
WWW.CS.Wright.edu/~tkprasad/VHDL/VHDL-AMS/START.html
on which it is written:
"[..]

[..] In the original VHDL-87 parser, [..] Furthermore, it vastly
improves the parsing of operators, though it is not entirely
``correct''. The current VHDL-AMS parser attempts to remedy these
problems, [..]

[..]"

It is written in vhdl.bnf in vhdl-rexlalr.1.2.tar.Z :
"[..]

[..] The syntax has been checked carefully against [LRM]:
[..] "IEEE Standard VHDL Language Reference Manual, IEEE, 1988". [..]

[..]"

It is written in vom/OBJECT-MODEL-INTRO in vhdl-object-model.tar.gz :
"[..]

VHDL '93 vs. VHDL '87
---------------------

One difference you may discover when parsing vhdl code which is '87
compatible
is that the '93 specification is completely backward compatible. The
only
inconsistency we discovered was that the production for
file_declaration in
VHDL '93 has no mode. This inconsistency has not been handled as of
yet.
Therefore, some VHDL '87 compatible specifications may not parse
correctly.
A specific example of a production which is valid under the '87 spec
but not the
'93:

file enum_file : enum_file_type is in "HOSTFILENAME";

The parser bombs on the mode "in".

[..]"