Re: [sv-bc] Re: [sv-ac] Is concurrent assertion not allowed inside task/function?

But I believe allowing it inside "always" is in some cases is equivalent to
allowing it inside "task" - potentially two different modeling styles, are
there semantic concerns (a task maybe called by several always blocks
etc.?).

Functions - maybe (though join_none is allowed, so if we were to think of
"spawning threads" it is similar).

Thanks
Srini
www.cvcblr.com

On Tue, Dec 15, 2009 at 8:16 PM, Korchemny, Dmitry <
dmitry.korchemny@intel.com> wrote:

> Hi Surya,
>
> I was wrong about the BNF, but note the following:
>
>
> The LRM states explicitly in 16.15 Concurrent assertions:
>
> A concurrent assertion statement may be specified in any of the following:
> - An always procedure or initial procedure as a statement, wherever these
> procedures may appear (see
> 9.2)
> - A module
> - An interface
> - A program
> - A generate block
> - A checker
>
> Thanks,
> Dmitry
>
>
> -----Original Message-----
> From: owner-sv-bc@server.eda.org [mailto:owner-sv-bc@server.eda.org] On
> Behalf Of Surya Pratik Saha
> Sent: Tuesday, December 15, 2009 12:02 PM
> To: Abhishek Muchandikar
> Cc: sv-bc@eda.org; sv-ac@server.eda.org; Adhip Das
> Subject: [sv-bc] Re: [sv-ac] Is concurrent assertion not allowed inside
> task/function?
>
> Hi Abhishek,
> Then LRM should have some text restricting that, but there is nothing
> like that. Is there any Mantis?
>
> Hi Shalom,
> BNF of both SV 2005 and SV 2009 draft 7a LRM allows it. Here is the
> snippet:
>
> task_declaration ::= task [ lifetime ] task_body_declaration
> task_body_declaration ::=
> [ interface_identifier . | class_scope ] task_identifier ;
> { tf_item_declaration }
> { statement_or_null }
> endtask [ : task_identifier ]
>
> statement_or_null ::=
> statement
> | { attribute_instance } ;
> statement ::= [ block_identifier : ] { attribute_instance } statement_item
> statement_item ::=
> [...]
> | procedural_assertion_statement
> [...]
>
> procedural_assertion_statement ::=
> concurrent_assertion_statement
> | immediate_assertion_statement
> | checker_instantiation
>
> So BNF does not restrict it.
>
> Regards
> Surya
>
>
>
> -------- Original Message  --------
> Subject: Re:[sv-ac] Is concurrent assertion not allowed inside
> task/function?
> From: Abhishek Muchandikar <Abhishek.Muchandikar@synopsys.com>
> To: Surya Pratik Saha <spsaha@cal.interrasystems.com>, sv-bc@eda.org
> <sv-bc@eda.org>, sv-ac@server.eda.org <sv-ac@eda.org>
> Cc: Adhip Das <adhip@cal.interrasystems.com>
> Date: Tuesday, December 15, 2009 3:20:36 PM
> > Hi,
> >
> > In my views, the core functionality of tasks and functions restricts such
> a kind of use model and is correct.
> > The intended use model for tasks and functions is ability to execute
> common procedures.
> > The result of these execution is either passed as a single value thru
> function or thru output/inout args from a task.
> >
> > How do you plan to see the assertion results thru them for a whole bunch
> of assertions encapsulate in them,
> > By nature assertion are declarative in form , spanning over the temporal
> domain.
> >
> > Also since functions are supposed to  execute in one time unit, it really
> is not feasible to have assertions in them spanning over a period of time.
> >
> > Thanks
> > Abhishek
> >
> > -----Original Message-----
> > From: owner-sv-ac@eda.org [mailto:owner-sv-ac@eda.org] On Behalf Of
> Surya Pratik Saha
> > Sent: Tuesday, December 15, 2009 2:40 PM
> > To: sv-bc@eda.org; sv-ac@server.eda.org
> > Cc: Adhip Das
> > Subject: [sv-ac] Is concurrent assertion not allowed inside
> task/function?
> >
> > Hi,
> > I did not see any restriction in the LRM that prevents concurrent
> > assertion statement inside task/function. Though all the standard
> > simulators fail for the following case for same reason:
> >
> > module top(input clk,a,b,c);
> >
> >         property prop;
> >                 @(posedge clk)  a ##1 b ##1 c;
> >         endproperty
> >         task tsk;
> >                 assert property(prop)
> >                             $display("\n time = %g , testname = %s
> Passed",$time,"test1_16_7");
> >                         else
> >                             $display("\n time = %g , testname = %s
> > Failed",$time,"test1_16_7");
> >
> >         endtask
> >
> >         function func();
> >                 assert property(prop)
> >                             $display("\n time = %g , testname = %s
> > Passed",$time,"test1_16_7");
> >                         else
> >                             $display("\n time = %g , testname = %s
> > Failed",$time,"test1_16_7");
> >
> >         endfunction
> >
> > endmodule
> >
> > Please comment on it.
> >
> >
>
>
>

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