RE: monte carlo and distribution functions

Correct. 1364-2005 allows using certain system functions in constant
expressions (math functions, conversion functions), but their arguments
have to be constant, just as in user-defined constant functions.

The functions $bits is part of SystemVerilog.
$sizeof does not exist. Maybe you mean $size, which is one of the
SystemVerilog array querying functions.
SystemVerilog allows $bits and array querying functions in constant
expressions.

However, neither Verilog nor SystemVerilog allow random or distribution
functions in constant expressions, even if their arguments are constant.

Shalom
 

> -----Original Message-----
> From: owner-verilog-ams@eda.org [mailto:owner-verilog-
> ams@eda.org] On Behalf Of Geoffrey.Coram
> Sent: Monday, January 30, 2006 4:29 PM
> To: Sri Chandra
> Cc: verilog-ams
> Subject: Re: monte carlo and distribution functions
> 
> Sri -
> I'm not sure that LRM 2.2 is clear about using system functions
> in
> parameter initialization.  Verilog 1364-2005, I think, started
> allowing
> this for a few "constant" functions, such as $bits, $sizeof --
> and
> all the math functions $sin, $cos, $tan.  But in 1364-2005, the
> arguments have to be constant_expressions, which rules out
> integer variables.
> 
> -Geoffrey
> 
> 
> Sri Chandra wrote:
> >
> > Hi Geoffrey,
> >
> > I thought allowing integer variables as seed is already fixed
> in LRM2.2.
> > If you look at section 10.3 it now accepts integers,
> parameters and
> > constant numbers.
> >
> > As far as the default expression for parameters are
> concerned, random
> > and distribution calls are allowed as default as long as the
> parameters
> > specified are constant expression (parameters or fixed
> constants). So in
> > this context one wouldnt be able to use integer variable as a
> seed.
> >
> > cheers,
> > Sri