Minutes from SV-AC Committee Meeting
Date: 2010-07-13
Time: 16:00 UTC (9:00 PDT)
Duration: 1.5 hours
Agenda
- Reminder of IEEE patent policy.
See:
http://standards.ieee.org/board/pat/pat-slideset.ppt
- Minutes approval
- Email ballot results
- Issue resolution/discussion
2732: Clarify timing diagram in Figure 16-4?Future value change
2398: Surprising (to some users) interaction between deferred assertions
& short-circuiting
2491: Conflicting rules in 16.17 (D7)
2557: Rules for passing automatic variables to sequence subroutines are
not clear
1756: The LRM does not indicate how the control tasks $asserton/off/kill
affect verification statements in initial blocks
1763: The LRM does not define whether assertion control tasks affect
sequence methods and events
2722: Errors in Figures 16-14, 16-15, and 16-16
2839: Contradictory statement of increment/decrement operators usage
1853: The proposal was already submitted by Brad Pierce, but apparently not
voted on. The proposal is fine, and we should conduct an email vote.
2485: Submitted a proposal to fix the wording for immediate assertion types.
2558: Submitted a proposal to clarify the restrictions on automatic/dynamic
variable references in a checker declaration
- Enhancement progress update
- Opens
Attendance Record:
Legend:
x = attended
- = missed
r = represented
. = not yet a member
v = valid voter (2 out of last 3 or 3/4 overall)
n = not a valid voter
t = chair eligible to vote only to make or break a tie
Attendance re-initialized on 2010-07-06:
v[xx] Laurence Bisht (Intel)
v[x-] Eduard Cerny (Synopsys)
v[xx] Ben Cohen
v[xx] Surrendra Dudani (Synopsys)
v[xx] Dana Fisman (Synopsys)
v[xx] John Havlicek (Freescale)
v[xx] Tapan Kapoor (Cadence)
t[xx] Dmitry Korchemny (Intel ¿ Chair)
v[xx] Scott Little (Freescale)
v[xx] Manisha Kulshrestha (Mentor Graphics)
v[xx] Anupam Prabhakar (Mentor Graphics)
v[xx] Erik Seligman (Intel)
v[x.] Samik Sengupta (Synopsys)
v[xx] Tom Thatcher (Sun Microsystems ¿ Co-Chair)
|- attendance on 2010-07-13
|--- voting eligibility on 2010-07-13
Minutes
1. Minutes from last meeting:
Eric: Move to approve minutes
Ben; Second
Voting results: 13y, 0n, 0a
2. E-mail Ballot results -- Dmitry
- Unanimous approval
Some question over proper font for variable names in text, but will
leave
it to editor
John suggested to send to sv-bc for review.
Dmitry will send it.
3. Issue resolution/discussion
Issue with variables (e-mail thread)
Dmitry: Issue reported was that variable names used in assertions
before declaration behaved differently. Rather than create
an implicit declaration of the variable, the simulators
seem to resolve the signal names at elaboration time, just
like the variable was a cross-module reference.
Ben: Variable should obey scoping rules
Ed: Don't want to change the way it works now.
This was how we intended it to work, although it wasn't
written into the LRM.
Dmitry: Some people may `include a file with assertions, but
assertions may reference variables not declared yet
Ed: Even if we wanted to change it, it would affect
Ben: Should we add to LRM
Ed: yes
Manisha: even immediate assertions?
Ben: Doesn't immediate assertion have to be in a process
Ed: Immediate assertions are different.
Dmitry: Checkers?
Ben: Should it follow module instantations?
Ed: Should follow assertion rules
Dmitry: May have to ask Working Group for permission to work on this.
Manisha: What about procedural concurrent assertions?
Require declaration before use?
Dmitry: I think yes.
2557
Eric: One sentence Change.
John: Would like to think about this more; perhaps an e-mail vote
John: Three points in time: observed region, where match occurs,
reactive region where subroutine executes, and
Does automatic variable exist at the match time?
Dmitry: Will call for an e-mail vote
2732 Dmitry: Postpone to next meeting
2938
Eric: Short-circuiting
Eric: Is this documented?
When you hit flush point: we don't report attemts so far
John: Does proposal change anything
Eric: Not suggesting changing anything
Dmitry: Will defer to next meeting,
2491
Eric: Not sure of the problem:
Has sent e-mail to Doron
John: doesn't think there is a problem.
We're not being careful about sequence declaration, vs
instance.
Rule e doesn't exclude instances
Rule f specifies case where you have to have an instance
Ed: Is "maximal property" defined
Is solutionjust to define the term?
What does "maximal property" mean?
John: Thinks that maximal property meant the largest expression you
could get using the property grammar. That doesn't include
disable iff, but does include the clocking statement.
Eric: John will write opinion as a note on the Mantis item.
Should we open separate Mantis to define "Maximal property"
Ed: Do we really need rule F
John: Maybe it doesn't need to be a normative restriction
Ed: Rule e subsumes f
John: Rule f points out one consequence of Rule e
4. Enhancements progress update
Real Types
Checker output arg
Interfaces & checkers
Assertion system functions
Interfaces & checkers
Ben: Wrote a use model
Ben: Question: Should checkers be able to drive interface inputs
Dmitry: Yes
Ed: Sometimes checker could be used as constraint.
Ben: OVM, VMM typically use classes tied to virtual interface.
But you can't have checker in class. so why is this needed?
Still unclear on use model.
Ben: Original thought was just to allow a better connection to a
checker.
Tom: Don't necessarily need to drive interface inputs for formal.
Instead, an assume property would constrain the value of the
input.
Assertion system function
Eric: Concentrating on errata now.
Clock inferenceing & sequence
Anupam: Have a good idea of what to propose.
Real types
Scott: Concentrating on errata.
Checker output arguments
Lawrence has documented use cases
Next meeting: Next week.