iverilog-devel

[Iverilog-devel] Patch for const integer foreign = "" attributes

[Stephen W. <st...@ic...>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


PR1869719 in Patches brings up the fact that nccoex (what is that?)
generates attributes of this form in Verilog that it generates.
The patch is a good start, but it parses only a very specific
case, and parses it as an unattached (and ignored) attributes.

I'm wondering if this attribute format is SystemVerilog-ish, given
that at least some other Verilog tools parse it. (Otherwise, Stefan
wouldn't be encountering it.) If so, can someone track down the
pertinent SystemVerilog babble? We may be able to actually do a
proper job of this, if it is documented somewhere. Why not add
smarter attribute to Icarus Verilog?

Perhaps NC Verilog documentation points us in the right direction.
(I'm guessing that nccoex is "NC COEXist" or something like that.)

- --
Steve Williams                "The woods are lovely, dark and deep.
steve at icarus.com           But I have promises to keep,
http://www.icarus.com         and lines to code before I sleep,
http://www.picturel.com       And lines to code before I sleep."
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (GNU/Linux)
Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org

iD8DBQFHjPoWrPt1Sc2b3ikRAk4zAKCKVYniJHyKN5VuHiyGJ8i9pDl0UACfXgCt
/Z7EO5jCiSw+E4DYxOHCytE=
=pkS8
-----END PGP SIGNATURE-----

Re: [Iverilog-devel] Patch for const integer foreign = "" attributes

[Stephen W. <st...@ic...>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Stephen Williams wrote:
> I'm wondering if this attribute format is SystemVerilog-ish, given
> that at least some other Verilog tools parse it. (Otherwise, Stefan
> wouldn't be encountering it.) If so, can someone track down the
> pertinent SystemVerilog babble? We may be able to actually do a
> proper job of this, if it is documented somewhere. Why not add
> smarter attribute to Icarus Verilog?

I've done a little digging. The "const" keyword in the example
appears to indeed be a part of SystemVerilog and is similar to
the localparam in behavior. (Except it can be used in a few more
places.)

My SystemVerilog draft is too old to show this, but I think the
attribute assignment may include a type declaration along with the
assignment. That would mean that in principle the existing attribute
code can be extended in a SV-ish way to make the given code work.
I think *this* is what we want to do.

- --
Steve Williams                "The woods are lovely, dark and deep.
steve at icarus.com           But I have promises to keep,
http://www.icarus.com         and lines to code before I sleep,
http://www.picturel.com       And lines to code before I sleep."
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (GNU/Linux)
Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org

iD8DBQFHjQtvrPt1Sc2b3ikRAikiAKDtIc8sSBecuiUwPlreuUfbbvRtagCbB2Oq
+vviAmHOFcU8ZvHLa6d6PXw=
=VMNd
-----END PGP SIGNATURE-----

Re: [Iverilog-devel] Patch for const integer foreign = "" attributes

[Cary R. <cy...@ya...>]

--- Stephen Williams <st...@ic...> wrote:
 
> My SystemVerilog draft is too old to show this, but I think the
> attribute assignment may include a type declaration along with the
> assignment. That would mean that in principle the existing attribute
> code can be extended in a SV-ish way to make the given code work.
> I think *this* is what we want to do.

I agree we should code to a standard. If this is supported in SV we need
to know what the particulars are. Unfortunately it appears the two people
most likely to implement it do not have access to the SV standard
(1800-2005).

>From memory I don't think the SV standard is too expensive, but it uses
the 1364-2005 standard as a base document. I only have a copy of
1364-2001, so I'm probably not going to spend the money to get both
standards just to enhance iverilog.

Cary


      ____________________________________________________________________________________
Looking for last minute shopping deals?  
Find them fast with Yahoo! Search.  http://tools.search.yahoo.com/newsearch/category.php?category=shopping

Re: [Iverilog-devel] Patch for const integer foreign = "" attributes

[Stephen W. <st...@ic...>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Cary R. wrote:
> --- Stephen Williams <st...@ic...> wrote:
>  
>> My SystemVerilog draft is too old to show this, but I think the
>> attribute assignment may include a type declaration along with the
>> assignment. That would mean that in principle the existing attribute
>> code can be extended in a SV-ish way to make the given code work.
>> I think *this* is what we want to do.
> 
> I agree we should code to a standard. If this is supported in SV we need
> to know what the particulars are. Unfortunately it appears the two people
> most likely to implement it do not have access to the SV standard
> (1800-2005).
> 
>>From memory I don't think the SV standard is too expensive, but it uses
> the 1364-2005 standard as a base document. I only have a copy of
> 1364-2001, so I'm probably not going to spend the money to get both
> standards just to enhance iverilog.

I have a copy of IEEE1364-1005 (printed) so I can make proper use of
the SystemVerilog standard. These standards are somewhat painful to
buy without funding, but I'll look into it.

- --
Steve Williams                "The woods are lovely, dark and deep.
steve at icarus.com           But I have promises to keep,
http://www.icarus.com         and lines to code before I sleep,
http://www.picturel.com       And lines to code before I sleep."
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (GNU/Linux)
Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org

iD8DBQFHjSN2rPt1Sc2b3ikRAqIXAJ0Q0rSNXxNnfozNqFc2jPWoNDuPbwCfWfLO
gTmbW7baMjvyrvzS0sI7D9U=
=4vF3
-----END PGP SIGNATURE-----